ddr: altera: Dissolve invocation of sdr_get_addr(&sdr_mgr_.*->.*)

[karo-tx-uboot.git] / drivers / ddr / altera / sequencer.c

/*
 * Copyright Altera Corporation (C) 2012-2015
 *
 * SPDX-License-Identifier:    BSD-3-Clause
 */

#include <common.h>
#include <asm/io.h>
#include <asm/arch/sdram.h>
#include "sequencer.h"
#include "sequencer_auto.h"
#include "sequencer_auto_ac_init.h"
#include "sequencer_auto_inst_init.h"
#include "sequencer_defines.h"

static void scc_mgr_load_dqs_for_write_group(uint32_t write_group);

static struct socfpga_sdr_rw_load_manager *sdr_rw_load_mgr_regs =
        (struct socfpga_sdr_rw_load_manager *)(SDR_PHYGRP_RWMGRGRP_ADDRESS | 0x800);

static struct socfpga_sdr_rw_load_jump_manager *sdr_rw_load_jump_mgr_regs =
        (struct socfpga_sdr_rw_load_jump_manager *)(SDR_PHYGRP_RWMGRGRP_ADDRESS | 0xC00);

static struct socfpga_sdr_reg_file *sdr_reg_file =
        (struct socfpga_sdr_reg_file *)SDR_PHYGRP_REGFILEGRP_ADDRESS;

static struct socfpga_sdr_scc_mgr *sdr_scc_mgr =
        (struct socfpga_sdr_scc_mgr *)(SDR_PHYGRP_SCCGRP_ADDRESS | 0xe00);

static struct socfpga_phy_mgr_cmd *phy_mgr_cmd =
        (struct socfpga_phy_mgr_cmd *)SDR_PHYGRP_PHYMGRGRP_ADDRESS;

static struct socfpga_phy_mgr_cfg *phy_mgr_cfg =
        (struct socfpga_phy_mgr_cfg *)(SDR_PHYGRP_PHYMGRGRP_ADDRESS | 0x40);

static struct socfpga_data_mgr *data_mgr =
        (struct socfpga_data_mgr *)(BASE_DATA_MGR);

#define DELTA_D         1
#define MGR_SELECT_MASK         0xf8000

/*
 * In order to reduce ROM size, most of the selectable calibration steps are
 * decided at compile time based on the user's calibration mode selection,
 * as captured by the STATIC_CALIB_STEPS selection below.
 *
 * However, to support simulation-time selection of fast simulation mode, where
 * we skip everything except the bare minimum, we need a few of the steps to
 * be dynamic.  In those cases, we either use the DYNAMIC_CALIB_STEPS for the
 * check, which is based on the rtl-supplied value, or we dynamically compute
 * the value to use based on the dynamically-chosen calibration mode
 */

#define DLEVEL 0
#define STATIC_IN_RTL_SIM 0
#define STATIC_SKIP_DELAY_LOOPS 0

#define STATIC_CALIB_STEPS (STATIC_IN_RTL_SIM | CALIB_SKIP_FULL_TEST | \
        STATIC_SKIP_DELAY_LOOPS)

/* calibration steps requested by the rtl */
uint16_t dyn_calib_steps;

/*
 * To make CALIB_SKIP_DELAY_LOOPS a dynamic conditional option
 * instead of static, we use boolean logic to select between
 * non-skip and skip values
 *
 * The mask is set to include all bits when not-skipping, but is
 * zero when skipping
 */

uint16_t skip_delay_mask;       /* mask off bits when skipping/not-skipping */

#define SKIP_DELAY_LOOP_VALUE_OR_ZERO(non_skip_value) \
        ((non_skip_value) & skip_delay_mask)

struct gbl_type *gbl;
struct param_type *param;
uint32_t curr_shadow_reg;

static uint32_t rw_mgr_mem_calibrate_write_test(uint32_t rank_bgn,
        uint32_t write_group, uint32_t use_dm,
        uint32_t all_correct, uint32_t *bit_chk, uint32_t all_ranks);

static u32 sdr_get_addr(u32 *base)
{
        u32 addr = (u32)base & MGR_SELECT_MASK;

        switch (addr) {
        case BASE_PHY_MGR:
                addr = (((u32)base >> 8) & (1 << 6)) | ((u32)base & 0x3f) |
                        SDR_PHYGRP_PHYMGRGRP_ADDRESS;
                break;
        case BASE_RW_MGR:
                addr = ((u32)base & 0x1fff) | SDR_PHYGRP_RWMGRGRP_ADDRESS;
                break;
        case BASE_DATA_MGR:
                addr = ((u32)base & 0x7ff) | SDR_PHYGRP_DATAMGRGRP_ADDRESS;
                break;
        case BASE_SCC_MGR:
                addr = ((u32)base & 0xfff) | SDR_PHYGRP_SCCGRP_ADDRESS;
                break;
        case BASE_REG_FILE:
                addr = ((u32)base & 0x7ff) | SDR_PHYGRP_REGFILEGRP_ADDRESS;
                break;
        case BASE_MMR:
                addr = ((u32)base & 0xfff) | SDR_CTRLGRP_ADDRESS;
                break;
        default:
                return -1;
        }

        return addr;
}

static void set_failing_group_stage(uint32_t group, uint32_t stage,
        uint32_t substage)
{
        /*
         * Only set the global stage if there was not been any other
         * failing group
         */
        if (gbl->error_stage == CAL_STAGE_NIL)  {
                gbl->error_substage = substage;
                gbl->error_stage = stage;
                gbl->error_group = group;
        }
}

static void reg_file_set_group(uint32_t set_group)
{
        u32 addr = (u32)&sdr_reg_file->cur_stage;

        /* Read the current group and stage */
        uint32_t cur_stage_group = readl(SOCFPGA_SDR_ADDRESS + addr);

        /* Clear the group */
        cur_stage_group &= 0x0000FFFF;

        /* Set the group */
        cur_stage_group |= (set_group << 16);

        /* Write the data back */
        writel(cur_stage_group, SOCFPGA_SDR_ADDRESS + addr);
}

static void reg_file_set_stage(uint32_t set_stage)
{
        u32 addr = (u32)&sdr_reg_file->cur_stage;

        /* Read the current group and stage */
        uint32_t cur_stage_group = readl(SOCFPGA_SDR_ADDRESS + addr);

        /* Clear the stage and substage */
        cur_stage_group &= 0xFFFF0000;

        /* Set the stage */
        cur_stage_group |= (set_stage & 0x000000FF);

        /* Write the data back */
        writel(cur_stage_group, SOCFPGA_SDR_ADDRESS + addr);
}

static void reg_file_set_sub_stage(uint32_t set_sub_stage)
{
        u32 addr = (u32)&sdr_reg_file->cur_stage;

        /* Read the current group and stage */
        uint32_t cur_stage_group = readl(SOCFPGA_SDR_ADDRESS + addr);

        /* Clear the substage */
        cur_stage_group &= 0xFFFF00FF;

        /* Set the sub stage */
        cur_stage_group |= ((set_sub_stage << 8) & 0x0000FF00);

        /* Write the data back */
        writel(cur_stage_group, SOCFPGA_SDR_ADDRESS + addr);
}

static void initialize(void)
{
        u32 addr = (u32)&phy_mgr_cfg->mux_sel;

        debug("%s:%d\n", __func__, __LINE__);
        /* USER calibration has control over path to memory */
        /*
         * In Hard PHY this is a 2-bit control:
         * 0: AFI Mux Select
         * 1: DDIO Mux Select
         */
        writel(0x3, SOCFPGA_SDR_ADDRESS + addr);

        /* USER memory clock is not stable we begin initialization  */
        addr = (u32)&phy_mgr_cfg->reset_mem_stbl;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        /* USER calibration status all set to zero */
        addr = (u32)&phy_mgr_cfg->cal_status;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&phy_mgr_cfg->cal_debug_info;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        if ((dyn_calib_steps & CALIB_SKIP_ALL) != CALIB_SKIP_ALL) {
                param->read_correct_mask_vg  = ((uint32_t)1 <<
                        (RW_MGR_MEM_DQ_PER_READ_DQS /
                        RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS)) - 1;
                param->write_correct_mask_vg = ((uint32_t)1 <<
                        (RW_MGR_MEM_DQ_PER_READ_DQS /
                        RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS)) - 1;
                param->read_correct_mask     = ((uint32_t)1 <<
                        RW_MGR_MEM_DQ_PER_READ_DQS) - 1;
                param->write_correct_mask    = ((uint32_t)1 <<
                        RW_MGR_MEM_DQ_PER_WRITE_DQS) - 1;
                param->dm_correct_mask       = ((uint32_t)1 <<
                        (RW_MGR_MEM_DATA_WIDTH / RW_MGR_MEM_DATA_MASK_WIDTH))
                        - 1;
        }
}

static void set_rank_and_odt_mask(uint32_t rank, uint32_t odt_mode)
{
        uint32_t odt_mask_0 = 0;
        uint32_t odt_mask_1 = 0;
        uint32_t cs_and_odt_mask;
        uint32_t addr;

        if (odt_mode == RW_MGR_ODT_MODE_READ_WRITE) {
                if (RW_MGR_MEM_NUMBER_OF_RANKS == 1) {
                        /*
                         * 1 Rank
                         * Read: ODT = 0
                         * Write: ODT = 1
                         */
                        odt_mask_0 = 0x0;
                        odt_mask_1 = 0x1;
                } else if (RW_MGR_MEM_NUMBER_OF_RANKS == 2) {
                        /* 2 Ranks */
                        if (RW_MGR_MEM_NUMBER_OF_CS_PER_DIMM == 1) {
                                /* - Dual-Slot , Single-Rank
                                 * (1 chip-select per DIMM)
                                 * OR
                                 * - RDIMM, 4 total CS (2 CS per DIMM)
                                 * means 2 DIMM
                                 * Since MEM_NUMBER_OF_RANKS is 2 they are
                                 * both single rank
                                 * with 2 CS each (special for RDIMM)
                                 * Read: Turn on ODT on the opposite rank
                                 * Write: Turn on ODT on all ranks
                                 */
                                odt_mask_0 = 0x3 & ~(1 << rank);
                                odt_mask_1 = 0x3;
                        } else {
                                /*
                                 * USER - Single-Slot , Dual-rank DIMMs
                                 * (2 chip-selects per DIMM)
                                 * USER Read: Turn on ODT off on all ranks
                                 * USER Write: Turn on ODT on active rank
                                 */
                                odt_mask_0 = 0x0;
                                odt_mask_1 = 0x3 & (1 << rank);
                        }
                } else {
                        /* 4 Ranks
                         * Read:
                         * ----------+-----------------------+
                         *           |                       |
                         *           |         ODT           |
                         * Read From +-----------------------+
                         *   Rank    |  3  |  2  |  1  |  0  |
                         * ----------+-----+-----+-----+-----+
                         *     0     |  0  |  1  |  0  |  0  |
                         *     1     |  1  |  0  |  0  |  0  |
                         *     2     |  0  |  0  |  0  |  1  |
                         *     3     |  0  |  0  |  1  |  0  |
                         * ----------+-----+-----+-----+-----+
                         *
                         * Write:
                         * ----------+-----------------------+
                         *           |                       |
                         *           |         ODT           |
                         * Write To  +-----------------------+
                         *   Rank    |  3  |  2  |  1  |  0  |
                         * ----------+-----+-----+-----+-----+
                         *     0     |  0  |  1  |  0  |  1  |
                         *     1     |  1  |  0  |  1  |  0  |
                         *     2     |  0  |  1  |  0  |  1  |
                         *     3     |  1  |  0  |  1  |  0  |
                         * ----------+-----+-----+-----+-----+
                         */
                        switch (rank) {
                        case 0:
                                odt_mask_0 = 0x4;
                                odt_mask_1 = 0x5;
                                break;
                        case 1:
                                odt_mask_0 = 0x8;
                                odt_mask_1 = 0xA;
                                break;
                        case 2:
                                odt_mask_0 = 0x1;
                                odt_mask_1 = 0x5;
                                break;
                        case 3:
                                odt_mask_0 = 0x2;
                                odt_mask_1 = 0xA;
                                break;
                        }
                }
        } else {
                odt_mask_0 = 0x0;
                odt_mask_1 = 0x0;
        }

        cs_and_odt_mask =
                (0xFF & ~(1 << rank)) |
                ((0xFF & odt_mask_0) << 8) |
                ((0xFF & odt_mask_1) << 16);
        addr = sdr_get_addr((u32 *)RW_MGR_SET_CS_AND_ODT_MASK);
        writel(cs_and_odt_mask, SOCFPGA_SDR_ADDRESS + addr);
}

static void scc_mgr_initialize(void)
{
        u32 addr = sdr_get_addr((u32 *)SCC_MGR_HHP_RFILE);

        /*
         * Clear register file for HPS
         * 16 (2^4) is the size of the full register file in the scc mgr:
         *      RFILE_DEPTH = log2(MEM_DQ_PER_DQS + 1 + MEM_DM_PER_DQS +
         * MEM_IF_READ_DQS_WIDTH - 1) + 1;
         */
        uint32_t i;
        for (i = 0; i < 16; i++) {
                debug_cond(DLEVEL == 1, "%s:%d: Clearing SCC RFILE index %u\n",
                           __func__, __LINE__, i);
                writel(0, SOCFPGA_SDR_ADDRESS + addr + (i << 2));
        }
}

static void scc_mgr_set_dqs_bus_in_delay(uint32_t read_group,
                                                uint32_t delay)
{
        u32 addr = sdr_get_addr((u32 *)SCC_MGR_DQS_IN_DELAY);

        /* Load the setting in the SCC manager */
        writel(delay, SOCFPGA_SDR_ADDRESS + addr + (read_group << 2));
}

static void scc_mgr_set_dqs_io_in_delay(uint32_t write_group,
        uint32_t delay)
{
        u32 addr = sdr_get_addr((u32 *)SCC_MGR_IO_IN_DELAY);

        writel(delay, SOCFPGA_SDR_ADDRESS + addr + (RW_MGR_MEM_DQ_PER_WRITE_DQS << 2));
}

static void scc_mgr_set_dqs_en_phase(uint32_t read_group, uint32_t phase)
{
        u32 addr = sdr_get_addr((u32 *)SCC_MGR_DQS_EN_PHASE);

        /* Load the setting in the SCC manager */
        writel(phase, SOCFPGA_SDR_ADDRESS + addr + (read_group << 2));
}

static void scc_mgr_set_dqs_en_phase_all_ranks(uint32_t read_group,
                                               uint32_t phase)
{
        uint32_t r;
        uint32_t update_scan_chains;
        uint32_t addr;

        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS;
             r += NUM_RANKS_PER_SHADOW_REG) {
                /*
                 * USER although the h/w doesn't support different phases per
                 * shadow register, for simplicity our scc manager modeling
                 * keeps different phase settings per shadow reg, and it's
                 * important for us to keep them in sync to match h/w.
                 * for efficiency, the scan chain update should occur only
                 * once to sr0.
                 */
                update_scan_chains = (r == 0) ? 1 : 0;

                scc_mgr_set_dqs_en_phase(read_group, phase);

                if (update_scan_chains) {
                        addr = (u32)&sdr_scc_mgr->dqs_ena;
                        writel(read_group, SOCFPGA_SDR_ADDRESS + addr);

                        addr = (u32)&sdr_scc_mgr->update;
                        writel(0, SOCFPGA_SDR_ADDRESS + addr);
                }
        }
}

static void scc_mgr_set_dqdqs_output_phase(uint32_t write_group,
                                                  uint32_t phase)
{
        u32 addr = sdr_get_addr((u32 *)SCC_MGR_DQDQS_OUT_PHASE);

        /* Load the setting in the SCC manager */
        writel(phase, SOCFPGA_SDR_ADDRESS + addr + (write_group << 2));
}

static void scc_mgr_set_dqdqs_output_phase_all_ranks(uint32_t write_group,
                                                     uint32_t phase)
{
        uint32_t r;
        uint32_t update_scan_chains;
        uint32_t addr;

        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS;
             r += NUM_RANKS_PER_SHADOW_REG) {
                /*
                 * USER although the h/w doesn't support different phases per
                 * shadow register, for simplicity our scc manager modeling
                 * keeps different phase settings per shadow reg, and it's
                 * important for us to keep them in sync to match h/w.
                 * for efficiency, the scan chain update should occur only
                 * once to sr0.
                 */
                update_scan_chains = (r == 0) ? 1 : 0;

                scc_mgr_set_dqdqs_output_phase(write_group, phase);

                if (update_scan_chains) {
                        addr = (u32)&sdr_scc_mgr->dqs_ena;
                        writel(write_group, SOCFPGA_SDR_ADDRESS + addr);

                        addr = (u32)&sdr_scc_mgr->update;
                        writel(0, SOCFPGA_SDR_ADDRESS + addr);
                }
        }
}

static void scc_mgr_set_dqs_en_delay(uint32_t read_group, uint32_t delay)
{
        uint32_t addr = sdr_get_addr((u32 *)SCC_MGR_DQS_EN_DELAY);

        /* Load the setting in the SCC manager */
        writel(delay + IO_DQS_EN_DELAY_OFFSET, SOCFPGA_SDR_ADDRESS + addr +
               (read_group << 2));
}

static void scc_mgr_set_dqs_en_delay_all_ranks(uint32_t read_group,
                                               uint32_t delay)
{
        uint32_t r;
        uint32_t addr;

        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS;
                r += NUM_RANKS_PER_SHADOW_REG) {
                scc_mgr_set_dqs_en_delay(read_group, delay);

                addr = (u32)&sdr_scc_mgr->dqs_ena;
                writel(read_group, SOCFPGA_SDR_ADDRESS + addr);
                /*
                 * In shadow register mode, the T11 settings are stored in
                 * registers in the core, which are updated by the DQS_ENA
                 * signals. Not issuing the SCC_MGR_UPD command allows us to
                 * save lots of rank switching overhead, by calling
                 * select_shadow_regs_for_update with update_scan_chains
                 * set to 0.
                 */
                addr = (u32)&sdr_scc_mgr->update;
                writel(0, SOCFPGA_SDR_ADDRESS + addr);
        }
        /*
         * In shadow register mode, the T11 settings are stored in
         * registers in the core, which are updated by the DQS_ENA
         * signals. Not issuing the SCC_MGR_UPD command allows us to
         * save lots of rank switching overhead, by calling
         * select_shadow_regs_for_update with update_scan_chains
         * set to 0.
         */
        addr = (u32)&sdr_scc_mgr->update;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);
}

static void scc_mgr_set_oct_out1_delay(uint32_t write_group, uint32_t delay)
{
        uint32_t read_group;
        uint32_t addr = sdr_get_addr((u32 *)SCC_MGR_OCT_OUT1_DELAY);

        /*
         * Load the setting in the SCC manager
         * Although OCT affects only write data, the OCT delay is controlled
         * by the DQS logic block which is instantiated once per read group.
         * For protocols where a write group consists of multiple read groups,
         * the setting must be set multiple times.
         */
        for (read_group = write_group * RW_MGR_MEM_IF_READ_DQS_WIDTH /
             RW_MGR_MEM_IF_WRITE_DQS_WIDTH;
             read_group < (write_group + 1) * RW_MGR_MEM_IF_READ_DQS_WIDTH /
             RW_MGR_MEM_IF_WRITE_DQS_WIDTH; ++read_group)
                writel(delay, SOCFPGA_SDR_ADDRESS + addr + (read_group << 2));
}

static void scc_mgr_set_dq_out1_delay(uint32_t write_group,
                                      uint32_t dq_in_group, uint32_t delay)
{
        uint32_t addr = sdr_get_addr((u32 *)SCC_MGR_IO_OUT1_DELAY);

        /* Load the setting in the SCC manager */
        writel(delay, SOCFPGA_SDR_ADDRESS + addr + (dq_in_group << 2));
}

static void scc_mgr_set_dq_in_delay(uint32_t write_group,
        uint32_t dq_in_group, uint32_t delay)
{
        uint32_t addr = sdr_get_addr((u32 *)SCC_MGR_IO_IN_DELAY);

        /* Load the setting in the SCC manager */
        writel(delay, SOCFPGA_SDR_ADDRESS + addr + (dq_in_group << 2));
}

static void scc_mgr_set_hhp_extras(void)
{
        /*
         * Load the fixed setting in the SCC manager
         * bits: 0:0 = 1'b1   - dqs bypass
         * bits: 1:1 = 1'b1   - dq bypass
         * bits: 4:2 = 3'b001   - rfifo_mode
         * bits: 6:5 = 2'b01  - rfifo clock_select
         * bits: 7:7 = 1'b0  - separate gating from ungating setting
         * bits: 8:8 = 1'b0  - separate OE from Output delay setting
         */
        uint32_t value = (0<<8) | (0<<7) | (1<<5) | (1<<2) | (1<<1) | (1<<0);
        uint32_t addr = sdr_get_addr((u32 *)SCC_MGR_HHP_GLOBALS);

        writel(value, SOCFPGA_SDR_ADDRESS + addr + SCC_MGR_HHP_EXTRAS_OFFSET);
}

static void scc_mgr_set_dqs_out1_delay(uint32_t write_group,
                                              uint32_t delay)
{
        uint32_t addr = sdr_get_addr((u32 *)SCC_MGR_IO_OUT1_DELAY);

        /* Load the setting in the SCC manager */
        writel(delay, SOCFPGA_SDR_ADDRESS + addr + (RW_MGR_MEM_DQ_PER_WRITE_DQS << 2));
}

static void scc_mgr_set_dm_out1_delay(uint32_t write_group,
                                             uint32_t dm, uint32_t delay)
{
        uint32_t addr = sdr_get_addr((u32 *)SCC_MGR_IO_OUT1_DELAY);

        /* Load the setting in the SCC manager */
        writel(delay, SOCFPGA_SDR_ADDRESS + addr +
                ((RW_MGR_MEM_DQ_PER_WRITE_DQS + 1 + dm) << 2));
}

/*
 * USER Zero all DQS config
 * TODO: maybe rename to scc_mgr_zero_dqs_config (or something)
 */
static void scc_mgr_zero_all(void)
{
        uint32_t i, r;
        uint32_t addr;

        /*
         * USER Zero all DQS config settings, across all groups and all
         * shadow registers
         */
        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS; r +=
             NUM_RANKS_PER_SHADOW_REG) {
                for (i = 0; i < RW_MGR_MEM_IF_READ_DQS_WIDTH; i++) {
                        /*
                         * The phases actually don't exist on a per-rank basis,
                         * but there's no harm updating them several times, so
                         * let's keep the code simple.
                         */
                        scc_mgr_set_dqs_bus_in_delay(i, IO_DQS_IN_RESERVE);
                        scc_mgr_set_dqs_en_phase(i, 0);
                        scc_mgr_set_dqs_en_delay(i, 0);
                }

                for (i = 0; i < RW_MGR_MEM_IF_WRITE_DQS_WIDTH; i++) {
                        scc_mgr_set_dqdqs_output_phase(i, 0);
                        /* av/cv don't have out2 */
                        scc_mgr_set_oct_out1_delay(i, IO_DQS_OUT_RESERVE);
                }
        }

        /* multicast to all DQS group enables */
        addr = (u32)&sdr_scc_mgr->dqs_ena;
        writel(0xff, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_scc_mgr->update;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);
}

static void scc_set_bypass_mode(uint32_t write_group, uint32_t mode)
{
        uint32_t addr;
        /* mode = 0 : Do NOT bypass - Half Rate Mode */
        /* mode = 1 : Bypass - Full Rate Mode */

        /* only need to set once for all groups, pins, dq, dqs, dm */
        if (write_group == 0) {
                debug_cond(DLEVEL == 1, "%s:%d Setting HHP Extras\n", __func__,
                           __LINE__);
                scc_mgr_set_hhp_extras();
                debug_cond(DLEVEL == 1, "%s:%d Done Setting HHP Extras\n",
                          __func__, __LINE__);
        }
        /* multicast to all DQ enables */
        addr = (u32)&sdr_scc_mgr->dq_ena;
        writel(0xff, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_scc_mgr->dm_ena;
        writel(0xff, SOCFPGA_SDR_ADDRESS + addr);

        /* update current DQS IO enable */
        addr = (u32)&sdr_scc_mgr->dqs_io_ena;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        /* update the DQS logic */
        addr = (u32)&sdr_scc_mgr->dqs_ena;
        writel(write_group, SOCFPGA_SDR_ADDRESS + addr);

        /* hit update */
        addr = (u32)&sdr_scc_mgr->update;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);
}

static void scc_mgr_zero_group(uint32_t write_group, uint32_t test_begin,
                               int32_t out_only)
{
        uint32_t i, r;
        uint32_t addr;

        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS; r +=
                NUM_RANKS_PER_SHADOW_REG) {
                /* Zero all DQ config settings */
                for (i = 0; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++) {
                        scc_mgr_set_dq_out1_delay(write_group, i, 0);
                        if (!out_only)
                                scc_mgr_set_dq_in_delay(write_group, i, 0);
                }

                /* multicast to all DQ enables */
                addr = (u32)&sdr_scc_mgr->dq_ena;
                writel(0xff, SOCFPGA_SDR_ADDRESS + addr);

                /* Zero all DM config settings */
                for (i = 0; i < RW_MGR_NUM_DM_PER_WRITE_GROUP; i++) {
                        scc_mgr_set_dm_out1_delay(write_group, i, 0);
                }

                /* multicast to all DM enables */
                addr = (u32)&sdr_scc_mgr->dm_ena;
                writel(0xff, SOCFPGA_SDR_ADDRESS + addr);

                /* zero all DQS io settings */
                if (!out_only)
                        scc_mgr_set_dqs_io_in_delay(write_group, 0);
                /* av/cv don't have out2 */
                scc_mgr_set_dqs_out1_delay(write_group, IO_DQS_OUT_RESERVE);
                scc_mgr_set_oct_out1_delay(write_group, IO_DQS_OUT_RESERVE);
                scc_mgr_load_dqs_for_write_group(write_group);

                /* multicast to all DQS IO enables (only 1) */
                addr = (u32)&sdr_scc_mgr->dqs_io_ena;
                writel(0, SOCFPGA_SDR_ADDRESS + addr);

                /* hit update to zero everything */
                addr = (u32)&sdr_scc_mgr->update;
                writel(0, SOCFPGA_SDR_ADDRESS + addr);
        }
}

/* load up dqs config settings */
static void scc_mgr_load_dqs(uint32_t dqs)
{
        uint32_t addr = (u32)&sdr_scc_mgr->dqs_ena;

        writel(dqs, SOCFPGA_SDR_ADDRESS + addr);
}

static void scc_mgr_load_dqs_for_write_group(uint32_t write_group)
{
        uint32_t read_group;
        uint32_t addr = (u32)&sdr_scc_mgr->dqs_ena;
        /*
         * Although OCT affects only write data, the OCT delay is controlled
         * by the DQS logic block which is instantiated once per read group.
         * For protocols where a write group consists of multiple read groups,
         * the setting must be scanned multiple times.
         */
        for (read_group = write_group * RW_MGR_MEM_IF_READ_DQS_WIDTH /
             RW_MGR_MEM_IF_WRITE_DQS_WIDTH;
             read_group < (write_group + 1) * RW_MGR_MEM_IF_READ_DQS_WIDTH /
             RW_MGR_MEM_IF_WRITE_DQS_WIDTH; ++read_group)
                writel(read_group, SOCFPGA_SDR_ADDRESS + addr);
}

/* load up dqs io config settings */
static void scc_mgr_load_dqs_io(void)
{
        uint32_t addr = (u32)&sdr_scc_mgr->dqs_io_ena;

        writel(0, SOCFPGA_SDR_ADDRESS + addr);
}

/* load up dq config settings */
static void scc_mgr_load_dq(uint32_t dq_in_group)
{
        uint32_t addr = (u32)&sdr_scc_mgr->dq_ena;

        writel(dq_in_group, SOCFPGA_SDR_ADDRESS + addr);
}

/* load up dm config settings */
static void scc_mgr_load_dm(uint32_t dm)
{
        uint32_t addr = (u32)&sdr_scc_mgr->dm_ena;

        writel(dm, SOCFPGA_SDR_ADDRESS + addr);
}

/*
 * apply and load a particular input delay for the DQ pins in a group
 * group_bgn is the index of the first dq pin (in the write group)
 */
static void scc_mgr_apply_group_dq_in_delay(uint32_t write_group,
                                            uint32_t group_bgn, uint32_t delay)
{
        uint32_t i, p;

        for (i = 0, p = group_bgn; i < RW_MGR_MEM_DQ_PER_READ_DQS; i++, p++) {
                scc_mgr_set_dq_in_delay(write_group, p, delay);
                scc_mgr_load_dq(p);
        }
}

/* apply and load a particular output delay for the DQ pins in a group */
static void scc_mgr_apply_group_dq_out1_delay(uint32_t write_group,
                                              uint32_t group_bgn,
                                              uint32_t delay1)
{
        uint32_t i, p;

        for (i = 0, p = group_bgn; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++, p++) {
                scc_mgr_set_dq_out1_delay(write_group, i, delay1);
                scc_mgr_load_dq(i);
        }
}

/* apply and load a particular output delay for the DM pins in a group */
static void scc_mgr_apply_group_dm_out1_delay(uint32_t write_group,
                                              uint32_t delay1)
{
        uint32_t i;

        for (i = 0; i < RW_MGR_NUM_DM_PER_WRITE_GROUP; i++) {
                scc_mgr_set_dm_out1_delay(write_group, i, delay1);
                scc_mgr_load_dm(i);
        }
}


/* apply and load delay on both DQS and OCT out1 */
static void scc_mgr_apply_group_dqs_io_and_oct_out1(uint32_t write_group,
                                                    uint32_t delay)
{
        scc_mgr_set_dqs_out1_delay(write_group, delay);
        scc_mgr_load_dqs_io();

        scc_mgr_set_oct_out1_delay(write_group, delay);
        scc_mgr_load_dqs_for_write_group(write_group);
}

/* apply a delay to the entire output side: DQ, DM, DQS, OCT */
static void scc_mgr_apply_group_all_out_delay_add(uint32_t write_group,
                                                  uint32_t group_bgn,
                                                  uint32_t delay)
{
        uint32_t i, p, new_delay;

        /* dq shift */
        for (i = 0, p = group_bgn; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++, p++) {
                new_delay = READ_SCC_DQ_OUT2_DELAY;
                new_delay += delay;

                if (new_delay > IO_IO_OUT2_DELAY_MAX) {
                        debug_cond(DLEVEL == 1, "%s:%d (%u, %u, %u) DQ[%u,%u]:\
                                   %u > %lu => %lu", __func__, __LINE__,
                                   write_group, group_bgn, delay, i, p, new_delay,
                                   (long unsigned int)IO_IO_OUT2_DELAY_MAX,
                                   (long unsigned int)IO_IO_OUT2_DELAY_MAX);
                        new_delay = IO_IO_OUT2_DELAY_MAX;
                }

                scc_mgr_load_dq(i);
        }

        /* dm shift */
        for (i = 0; i < RW_MGR_NUM_DM_PER_WRITE_GROUP; i++) {
                new_delay = READ_SCC_DM_IO_OUT2_DELAY;
                new_delay += delay;

                if (new_delay > IO_IO_OUT2_DELAY_MAX) {
                        debug_cond(DLEVEL == 1, "%s:%d (%u, %u, %u) DM[%u]:\
                                   %u > %lu => %lu\n",  __func__, __LINE__,
                                   write_group, group_bgn, delay, i, new_delay,
                                   (long unsigned int)IO_IO_OUT2_DELAY_MAX,
                                   (long unsigned int)IO_IO_OUT2_DELAY_MAX);
                        new_delay = IO_IO_OUT2_DELAY_MAX;
                }

                scc_mgr_load_dm(i);
        }

        /* dqs shift */
        new_delay = READ_SCC_DQS_IO_OUT2_DELAY;
        new_delay += delay;

        if (new_delay > IO_IO_OUT2_DELAY_MAX) {
                debug_cond(DLEVEL == 1, "%s:%d (%u, %u, %u) DQS: %u > %d => %d;"
                           " adding %u to OUT1\n", __func__, __LINE__,
                           write_group, group_bgn, delay, new_delay,
                           IO_IO_OUT2_DELAY_MAX, IO_IO_OUT2_DELAY_MAX,
                           new_delay - IO_IO_OUT2_DELAY_MAX);
                scc_mgr_set_dqs_out1_delay(write_group, new_delay -
                                           IO_IO_OUT2_DELAY_MAX);
                new_delay = IO_IO_OUT2_DELAY_MAX;
        }

        scc_mgr_load_dqs_io();

        /* oct shift */
        new_delay = READ_SCC_OCT_OUT2_DELAY;
        new_delay += delay;

        if (new_delay > IO_IO_OUT2_DELAY_MAX) {
                debug_cond(DLEVEL == 1, "%s:%d (%u, %u, %u) DQS: %u > %d => %d;"
                           " adding %u to OUT1\n", __func__, __LINE__,
                           write_group, group_bgn, delay, new_delay,
                           IO_IO_OUT2_DELAY_MAX, IO_IO_OUT2_DELAY_MAX,
                           new_delay - IO_IO_OUT2_DELAY_MAX);
                scc_mgr_set_oct_out1_delay(write_group, new_delay -
                                           IO_IO_OUT2_DELAY_MAX);
                new_delay = IO_IO_OUT2_DELAY_MAX;
        }

        scc_mgr_load_dqs_for_write_group(write_group);
}

/*
 * USER apply a delay to the entire output side (DQ, DM, DQS, OCT)
 * and to all ranks
 */
static void scc_mgr_apply_group_all_out_delay_add_all_ranks(
        uint32_t write_group, uint32_t group_bgn, uint32_t delay)
{
        uint32_t r;
        uint32_t addr = (u32)&sdr_scc_mgr->update;

        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS;
                r += NUM_RANKS_PER_SHADOW_REG) {
                scc_mgr_apply_group_all_out_delay_add(write_group,
                                                      group_bgn, delay);
                writel(0, SOCFPGA_SDR_ADDRESS + addr);
        }
}

/* optimization used to recover some slots in ddr3 inst_rom */
/* could be applied to other protocols if we wanted to */
static void set_jump_as_return(void)
{
        uint32_t addr = (u32)&sdr_rw_load_mgr_regs->load_cntr0;

        /*
         * to save space, we replace return with jump to special shared
         * RETURN instruction so we set the counter to large value so that
         * we always jump
         */
        writel(0xff, SOCFPGA_SDR_ADDRESS + addr);
        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add0;
        writel(RW_MGR_RETURN, SOCFPGA_SDR_ADDRESS + addr);
}

/*
 * should always use constants as argument to ensure all computations are
 * performed at compile time
 */
static void delay_for_n_mem_clocks(const uint32_t clocks)
{
        uint32_t afi_clocks;
        uint8_t inner = 0;
        uint8_t outer = 0;
        uint16_t c_loop = 0;
        uint32_t addr;

        debug("%s:%d: clocks=%u ... start\n", __func__, __LINE__, clocks);


        afi_clocks = (clocks + AFI_RATE_RATIO-1) / AFI_RATE_RATIO;
        /* scale (rounding up) to get afi clocks */

        /*
         * Note, we don't bother accounting for being off a little bit
         * because of a few extra instructions in outer loops
         * Note, the loops have a test at the end, and do the test before
         * the decrement, and so always perform the loop
         * 1 time more than the counter value
         */
        if (afi_clocks == 0) {
                ;
        } else if (afi_clocks <= 0x100) {
                inner = afi_clocks-1;
                outer = 0;
                c_loop = 0;
        } else if (afi_clocks <= 0x10000) {
                inner = 0xff;
                outer = (afi_clocks-1) >> 8;
                c_loop = 0;
        } else {
                inner = 0xff;
                outer = 0xff;
                c_loop = (afi_clocks-1) >> 16;
        }

        /*
         * rom instructions are structured as follows:
         *
         *    IDLE_LOOP2: jnz cntr0, TARGET_A
         *    IDLE_LOOP1: jnz cntr1, TARGET_B
         *                return
         *
         * so, when doing nested loops, TARGET_A is set to IDLE_LOOP2, and
         * TARGET_B is set to IDLE_LOOP2 as well
         *
         * if we have no outer loop, though, then we can use IDLE_LOOP1 only,
         * and set TARGET_B to IDLE_LOOP1 and we skip IDLE_LOOP2 entirely
         *
         * a little confusing, but it helps save precious space in the inst_rom
         * and sequencer rom and keeps the delays more accurate and reduces
         * overhead
         */
        if (afi_clocks <= 0x100) {
                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr1;
                writel(SKIP_DELAY_LOOP_VALUE_OR_ZERO(inner), SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add1;
                writel(RW_MGR_IDLE_LOOP1, SOCFPGA_SDR_ADDRESS + addr);

                addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                writel(RW_MGR_IDLE_LOOP1, SOCFPGA_SDR_ADDRESS + addr);
        } else {
                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr0;
                writel(SKIP_DELAY_LOOP_VALUE_OR_ZERO(inner), SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr1;
                writel(SKIP_DELAY_LOOP_VALUE_OR_ZERO(outer), SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add0;
                writel(RW_MGR_IDLE_LOOP2, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add1;
                writel(RW_MGR_IDLE_LOOP2, SOCFPGA_SDR_ADDRESS + addr);

                /* hack to get around compiler not being smart enough */
                if (afi_clocks <= 0x10000) {
                        /* only need to run once */
                        addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                        writel(RW_MGR_IDLE_LOOP2, SOCFPGA_SDR_ADDRESS + addr);
                } else {
                        do {
                                addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                                writel(RW_MGR_IDLE_LOOP2, SOCFPGA_SDR_ADDRESS + addr);
                        } while (c_loop-- != 0);
                }
        }
        debug("%s:%d clocks=%u ... end\n", __func__, __LINE__, clocks);
}

static void rw_mgr_mem_initialize(void)
{
        uint32_t r;
        uint32_t addr;

        debug("%s:%d\n", __func__, __LINE__);

        /* The reset / cke part of initialization is broadcasted to all ranks */
        addr = sdr_get_addr((u32 *)RW_MGR_SET_CS_AND_ODT_MASK);
        writel(RW_MGR_RANK_ALL, SOCFPGA_SDR_ADDRESS + addr);

        /*
         * Here's how you load register for a loop
         * Counters are located @ 0x800
         * Jump address are located @ 0xC00
         * For both, registers 0 to 3 are selected using bits 3 and 2, like
         * in 0x800, 0x804, 0x808, 0x80C and 0xC00, 0xC04, 0xC08, 0xC0C
         * I know this ain't pretty, but Avalon bus throws away the 2 least
         * significant bits
         */

        /* start with memory RESET activated */

        /* tINIT = 200us */

        /*
         * 200us @ 266MHz (3.75 ns) ~ 54000 clock cycles
         * If a and b are the number of iteration in 2 nested loops
         * it takes the following number of cycles to complete the operation:
         * number_of_cycles = ((2 + n) * a + 2) * b
         * where n is the number of instruction in the inner loop
         * One possible solution is n = 0 , a = 256 , b = 106 => a = FF,
         * b = 6A
         */

        /* Load counters */
        addr = (u32)&sdr_rw_load_mgr_regs->load_cntr0;
        writel(SKIP_DELAY_LOOP_VALUE_OR_ZERO(SEQ_TINIT_CNTR0_VAL),
               SOCFPGA_SDR_ADDRESS + addr);
        addr = (u32)&sdr_rw_load_mgr_regs->load_cntr1;
        writel(SKIP_DELAY_LOOP_VALUE_OR_ZERO(SEQ_TINIT_CNTR1_VAL),
               SOCFPGA_SDR_ADDRESS + addr);
        addr = (u32)&sdr_rw_load_mgr_regs->load_cntr2;
        writel(SKIP_DELAY_LOOP_VALUE_OR_ZERO(SEQ_TINIT_CNTR2_VAL),
               SOCFPGA_SDR_ADDRESS + addr);

        /* Load jump address */
        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add0;
        writel(RW_MGR_INIT_RESET_0_CKE_0, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add1;
        writel(RW_MGR_INIT_RESET_0_CKE_0, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add2;
        writel(RW_MGR_INIT_RESET_0_CKE_0, SOCFPGA_SDR_ADDRESS + addr);

        /* Execute count instruction */
        addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
        writel(RW_MGR_INIT_RESET_0_CKE_0, SOCFPGA_SDR_ADDRESS + addr);

        /* indicate that memory is stable */
        addr = (u32)&phy_mgr_cfg->reset_mem_stbl;
        writel(1, SOCFPGA_SDR_ADDRESS + addr);

        /*
         * transition the RESET to high
         * Wait for 500us
         */

        /*
         * 500us @ 266MHz (3.75 ns) ~ 134000 clock cycles
         * If a and b are the number of iteration in 2 nested loops
         * it takes the following number of cycles to complete the operation
         * number_of_cycles = ((2 + n) * a + 2) * b
         * where n is the number of instruction in the inner loop
         * One possible solution is n = 2 , a = 131 , b = 256 => a = 83,
         * b = FF
         */

        /* Load counters */
        addr = (u32)&sdr_rw_load_mgr_regs->load_cntr0;
        writel(SKIP_DELAY_LOOP_VALUE_OR_ZERO(SEQ_TRESET_CNTR0_VAL),
               SOCFPGA_SDR_ADDRESS + addr);
        addr = (u32)&sdr_rw_load_mgr_regs->load_cntr1;
        writel(SKIP_DELAY_LOOP_VALUE_OR_ZERO(SEQ_TRESET_CNTR1_VAL),
               SOCFPGA_SDR_ADDRESS + addr);
        addr = (u32)&sdr_rw_load_mgr_regs->load_cntr2;
        writel(SKIP_DELAY_LOOP_VALUE_OR_ZERO(SEQ_TRESET_CNTR2_VAL),
               SOCFPGA_SDR_ADDRESS + addr);

        /* Load jump address */
        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add0;
        writel(RW_MGR_INIT_RESET_1_CKE_0, SOCFPGA_SDR_ADDRESS + addr);
        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add1;
        writel(RW_MGR_INIT_RESET_1_CKE_0, SOCFPGA_SDR_ADDRESS + addr);
        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add2;
        writel(RW_MGR_INIT_RESET_1_CKE_0, SOCFPGA_SDR_ADDRESS + addr);

        addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
        writel(RW_MGR_INIT_RESET_1_CKE_0, SOCFPGA_SDR_ADDRESS + addr);

        /* bring up clock enable */

        /* tXRP < 250 ck cycles */
        delay_for_n_mem_clocks(250);

        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS; r++) {
                if (param->skip_ranks[r]) {
                        /* request to skip the rank */
                        continue;
                }

                /* set rank */
                set_rank_and_odt_mask(r, RW_MGR_ODT_MODE_OFF);

                /*
                 * USER Use Mirror-ed commands for odd ranks if address
                 * mirrorring is on
                 */
                if ((RW_MGR_MEM_ADDRESS_MIRRORING >> r) & 0x1) {
                        set_jump_as_return();
                        addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                        writel(RW_MGR_MRS2_MIRR, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS3_MIRR, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS1_MIRR, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS0_DLL_RESET_MIRR, SOCFPGA_SDR_ADDRESS + addr);
                } else {
                        set_jump_as_return();
                        addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                        writel(RW_MGR_MRS2, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS3, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS1, SOCFPGA_SDR_ADDRESS + addr);
                        set_jump_as_return();
                        writel(RW_MGR_MRS0_DLL_RESET, SOCFPGA_SDR_ADDRESS + addr);
                }
                set_jump_as_return();
                addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                writel(RW_MGR_ZQCL, SOCFPGA_SDR_ADDRESS + addr);

                /* tZQinit = tDLLK = 512 ck cycles */
                delay_for_n_mem_clocks(512);
        }
}

/*
 * At the end of calibration we have to program the user settings in, and
 * USER  hand off the memory to the user.
 */
static void rw_mgr_mem_handoff(void)
{
        uint32_t r;
        uint32_t addr;

        debug("%s:%d\n", __func__, __LINE__);
        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS; r++) {
                if (param->skip_ranks[r])
                        /* request to skip the rank */
                        continue;
                /* set rank */
                set_rank_and_odt_mask(r, RW_MGR_ODT_MODE_OFF);

                /* precharge all banks ... */
                addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                writel(RW_MGR_PRECHARGE_ALL, SOCFPGA_SDR_ADDRESS + addr);

                /* load up MR settings specified by user */

                /*
                 * Use Mirror-ed commands for odd ranks if address
                 * mirrorring is on
                 */
                addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                if ((RW_MGR_MEM_ADDRESS_MIRRORING >> r) & 0x1) {
                        set_jump_as_return();
                        writel(RW_MGR_MRS2_MIRR, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS3_MIRR, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS1_MIRR, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS0_USER_MIRR, SOCFPGA_SDR_ADDRESS + addr);
                } else {
                        set_jump_as_return();
                        writel(RW_MGR_MRS2, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS3, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS1, SOCFPGA_SDR_ADDRESS + addr);
                        delay_for_n_mem_clocks(4);
                        set_jump_as_return();
                        writel(RW_MGR_MRS0_USER, SOCFPGA_SDR_ADDRESS + addr);
                }
                /*
                 * USER  need to wait tMOD (12CK or 15ns) time before issuing
                 * other commands, but we will have plenty of NIOS cycles before
                 * actual handoff so its okay.
                 */
        }
}

/*
 * performs a guaranteed read on the patterns we are going to use during a
 * read test to ensure memory works
 */
static uint32_t rw_mgr_mem_calibrate_read_test_patterns(uint32_t rank_bgn,
        uint32_t group, uint32_t num_tries, uint32_t *bit_chk,
        uint32_t all_ranks)
{
        uint32_t r, vg;
        uint32_t correct_mask_vg;
        uint32_t tmp_bit_chk;
        uint32_t rank_end = all_ranks ? RW_MGR_MEM_NUMBER_OF_RANKS :
                (rank_bgn + NUM_RANKS_PER_SHADOW_REG);
        uint32_t addr;
        uint32_t base_rw_mgr;

        *bit_chk = param->read_correct_mask;
        correct_mask_vg = param->read_correct_mask_vg;

        for (r = rank_bgn; r < rank_end; r++) {
                if (param->skip_ranks[r])
                        /* request to skip the rank */
                        continue;

                /* set rank */
                set_rank_and_odt_mask(r, RW_MGR_ODT_MODE_READ_WRITE);

                /* Load up a constant bursts of read commands */
                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr0;
                writel(0x20, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add0;
                writel(RW_MGR_GUARANTEED_READ, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr1;
                writel(0x20, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add1;
                writel(RW_MGR_GUARANTEED_READ_CONT, SOCFPGA_SDR_ADDRESS + addr);

                tmp_bit_chk = 0;
                for (vg = RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS-1; ; vg--) {
                        /* reset the fifos to get pointers to known state */

                        addr = (u32)&phy_mgr_cmd->fifo_reset;
                        writel(0, SOCFPGA_SDR_ADDRESS + addr);
                        addr = sdr_get_addr((u32 *)RW_MGR_RESET_READ_DATAPATH);
                        writel(0, SOCFPGA_SDR_ADDRESS + addr);

                        tmp_bit_chk = tmp_bit_chk << (RW_MGR_MEM_DQ_PER_READ_DQS
                                / RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS);

                        addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                        writel(RW_MGR_GUARANTEED_READ, SOCFPGA_SDR_ADDRESS + addr +
                               ((group * RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS +
                                vg) << 2));

                        addr = SDR_PHYGRP_RWMGRGRP_ADDRESS;
                        base_rw_mgr = readl(SOCFPGA_SDR_ADDRESS + addr);
                        tmp_bit_chk = tmp_bit_chk | (correct_mask_vg & (~base_rw_mgr));

                        if (vg == 0)
                                break;
                }
                *bit_chk &= tmp_bit_chk;
        }

        addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
        writel(RW_MGR_CLEAR_DQS_ENABLE, SOCFPGA_SDR_ADDRESS + addr + (group << 2));

        set_rank_and_odt_mask(0, RW_MGR_ODT_MODE_OFF);
        debug_cond(DLEVEL == 1, "%s:%d test_load_patterns(%u,ALL) => (%u == %u) =>\
                   %lu\n", __func__, __LINE__, group, *bit_chk, param->read_correct_mask,
                   (long unsigned int)(*bit_chk == param->read_correct_mask));
        return *bit_chk == param->read_correct_mask;
}

static uint32_t rw_mgr_mem_calibrate_read_test_patterns_all_ranks
        (uint32_t group, uint32_t num_tries, uint32_t *bit_chk)
{
        return rw_mgr_mem_calibrate_read_test_patterns(0, group,
                num_tries, bit_chk, 1);
}

/* load up the patterns we are going to use during a read test */
static void rw_mgr_mem_calibrate_read_load_patterns(uint32_t rank_bgn,
        uint32_t all_ranks)
{
        uint32_t r;
        uint32_t addr;
        uint32_t rank_end = all_ranks ? RW_MGR_MEM_NUMBER_OF_RANKS :
                (rank_bgn + NUM_RANKS_PER_SHADOW_REG);

        debug("%s:%d\n", __func__, __LINE__);
        for (r = rank_bgn; r < rank_end; r++) {
                if (param->skip_ranks[r])
                        /* request to skip the rank */
                        continue;

                /* set rank */
                set_rank_and_odt_mask(r, RW_MGR_ODT_MODE_READ_WRITE);

                /* Load up a constant bursts */
                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr0;
                writel(0x20, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add0;
                writel(RW_MGR_GUARANTEED_WRITE_WAIT0, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr1;
                writel(0x20, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add1;
                writel(RW_MGR_GUARANTEED_WRITE_WAIT1, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr2;
                writel(0x04, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add2;
                writel(RW_MGR_GUARANTEED_WRITE_WAIT2, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr3;
                writel(0x04, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add3;
                writel(RW_MGR_GUARANTEED_WRITE_WAIT3, SOCFPGA_SDR_ADDRESS + addr);

                addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                writel(RW_MGR_GUARANTEED_WRITE, SOCFPGA_SDR_ADDRESS + addr);
        }

        set_rank_and_odt_mask(0, RW_MGR_ODT_MODE_OFF);
}

/*
 * try a read and see if it returns correct data back. has dummy reads
 * inserted into the mix used to align dqs enable. has more thorough checks
 * than the regular read test.
 */
static uint32_t rw_mgr_mem_calibrate_read_test(uint32_t rank_bgn, uint32_t group,
        uint32_t num_tries, uint32_t all_correct, uint32_t *bit_chk,
        uint32_t all_groups, uint32_t all_ranks)
{
        uint32_t r, vg;
        uint32_t correct_mask_vg;
        uint32_t tmp_bit_chk;
        uint32_t rank_end = all_ranks ? RW_MGR_MEM_NUMBER_OF_RANKS :
                (rank_bgn + NUM_RANKS_PER_SHADOW_REG);
        uint32_t addr;
        uint32_t base_rw_mgr;

        *bit_chk = param->read_correct_mask;
        correct_mask_vg = param->read_correct_mask_vg;

        uint32_t quick_read_mode = (((STATIC_CALIB_STEPS) &
                CALIB_SKIP_DELAY_SWEEPS) && ENABLE_SUPER_QUICK_CALIBRATION);

        for (r = rank_bgn; r < rank_end; r++) {
                if (param->skip_ranks[r])
                        /* request to skip the rank */
                        continue;

                /* set rank */
                set_rank_and_odt_mask(r, RW_MGR_ODT_MODE_READ_WRITE);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr1;
                writel(0x10, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add1;
                writel(RW_MGR_READ_B2B_WAIT1, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr2;
                writel(0x10, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add2;
                writel(RW_MGR_READ_B2B_WAIT2, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr0;
                if (quick_read_mode)
                        writel(0x1, SOCFPGA_SDR_ADDRESS + addr);
                        /* need at least two (1+1) reads to capture failures */
                else if (all_groups)
                        writel(0x06, SOCFPGA_SDR_ADDRESS + addr);
                else
                        writel(0x32, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add0;
                writel(RW_MGR_READ_B2B, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr3;
                if (all_groups)
                        writel(RW_MGR_MEM_IF_READ_DQS_WIDTH *
                               RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS - 1,
                               SOCFPGA_SDR_ADDRESS + addr);
                else
                        writel(0x0, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add3;
                writel(RW_MGR_READ_B2B, SOCFPGA_SDR_ADDRESS + addr);

                tmp_bit_chk = 0;
                for (vg = RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS-1; ; vg--) {
                        /* reset the fifos to get pointers to known state */
                        addr = (u32)&phy_mgr_cmd->fifo_reset;
                        writel(0, SOCFPGA_SDR_ADDRESS + addr);
                        addr = sdr_get_addr((u32 *)RW_MGR_RESET_READ_DATAPATH);
                        writel(0, SOCFPGA_SDR_ADDRESS + addr);

                        tmp_bit_chk = tmp_bit_chk << (RW_MGR_MEM_DQ_PER_READ_DQS
                                / RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS);

                        addr = sdr_get_addr((u32 *)(all_groups ? RW_MGR_RUN_ALL_GROUPS :
                                            RW_MGR_RUN_SINGLE_GROUP));
                        writel(RW_MGR_READ_B2B, SOCFPGA_SDR_ADDRESS + addr +
                               ((group * RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS +
                               vg) << 2));

                        addr = SDR_PHYGRP_RWMGRGRP_ADDRESS;
                        base_rw_mgr = readl(SOCFPGA_SDR_ADDRESS + addr);
                        tmp_bit_chk = tmp_bit_chk | (correct_mask_vg & ~(base_rw_mgr));

                        if (vg == 0)
                                break;
                }
                *bit_chk &= tmp_bit_chk;
        }

        addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
        writel(RW_MGR_CLEAR_DQS_ENABLE, SOCFPGA_SDR_ADDRESS + addr + (group << 2));

        if (all_correct) {
                set_rank_and_odt_mask(0, RW_MGR_ODT_MODE_OFF);
                debug_cond(DLEVEL == 2, "%s:%d read_test(%u,ALL,%u) =>\
                           (%u == %u) => %lu", __func__, __LINE__, group,
                           all_groups, *bit_chk, param->read_correct_mask,
                           (long unsigned int)(*bit_chk ==
                           param->read_correct_mask));
                return *bit_chk == param->read_correct_mask;
        } else  {
                set_rank_and_odt_mask(0, RW_MGR_ODT_MODE_OFF);
                debug_cond(DLEVEL == 2, "%s:%d read_test(%u,ONE,%u) =>\
                           (%u != %lu) => %lu\n", __func__, __LINE__,
                           group, all_groups, *bit_chk, (long unsigned int)0,
                           (long unsigned int)(*bit_chk != 0x00));
                return *bit_chk != 0x00;
        }
}

static uint32_t rw_mgr_mem_calibrate_read_test_all_ranks(uint32_t group,
        uint32_t num_tries, uint32_t all_correct, uint32_t *bit_chk,
        uint32_t all_groups)
{
        return rw_mgr_mem_calibrate_read_test(0, group, num_tries, all_correct,
                                              bit_chk, all_groups, 1);
}

static void rw_mgr_incr_vfifo(uint32_t grp, uint32_t *v)
{
        uint32_t addr = (u32)&phy_mgr_cmd->inc_vfifo_hard_phy;

        writel(grp, SOCFPGA_SDR_ADDRESS + addr);
        (*v)++;
}

static void rw_mgr_decr_vfifo(uint32_t grp, uint32_t *v)
{
        uint32_t i;

        for (i = 0; i < VFIFO_SIZE-1; i++)
                rw_mgr_incr_vfifo(grp, v);
}

static int find_vfifo_read(uint32_t grp, uint32_t *bit_chk)
{
        uint32_t  v;
        uint32_t fail_cnt = 0;
        uint32_t test_status;

        for (v = 0; v < VFIFO_SIZE; ) {
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: vfifo %u\n",
                           __func__, __LINE__, v);
                test_status = rw_mgr_mem_calibrate_read_test_all_ranks
                        (grp, 1, PASS_ONE_BIT, bit_chk, 0);
                if (!test_status) {
                        fail_cnt++;

                        if (fail_cnt == 2)
                                break;
                }

                /* fiddle with FIFO */
                rw_mgr_incr_vfifo(grp, &v);
        }

        if (v >= VFIFO_SIZE) {
                /* no failing read found!! Something must have gone wrong */
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: vfifo failed\n",
                           __func__, __LINE__);
                return 0;
        } else {
                return v;
        }
}

static int find_working_phase(uint32_t *grp, uint32_t *bit_chk,
                              uint32_t dtaps_per_ptap, uint32_t *work_bgn,
                              uint32_t *v, uint32_t *d, uint32_t *p,
                              uint32_t *i, uint32_t *max_working_cnt)
{
        uint32_t found_begin = 0;
        uint32_t tmp_delay = 0;
        uint32_t test_status;

        for (*d = 0; *d <= dtaps_per_ptap; (*d)++, tmp_delay +=
                IO_DELAY_PER_DQS_EN_DCHAIN_TAP) {
                *work_bgn = tmp_delay;
                scc_mgr_set_dqs_en_delay_all_ranks(*grp, *d);

                for (*i = 0; *i < VFIFO_SIZE; (*i)++) {
                        for (*p = 0; *p <= IO_DQS_EN_PHASE_MAX; (*p)++, *work_bgn +=
                                IO_DELAY_PER_OPA_TAP) {
                                scc_mgr_set_dqs_en_phase_all_ranks(*grp, *p);

                                test_status =
                                rw_mgr_mem_calibrate_read_test_all_ranks
                                (*grp, 1, PASS_ONE_BIT, bit_chk, 0);

                                if (test_status) {
                                        *max_working_cnt = 1;
                                        found_begin = 1;
                                        break;
                                }
                        }

                        if (found_begin)
                                break;

                        if (*p > IO_DQS_EN_PHASE_MAX)
                                /* fiddle with FIFO */
                                rw_mgr_incr_vfifo(*grp, v);
                }

                if (found_begin)
                        break;
        }

        if (*i >= VFIFO_SIZE) {
                /* cannot find working solution */
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: no vfifo/\
                           ptap/dtap\n", __func__, __LINE__);
                return 0;
        } else {
                return 1;
        }
}

static void sdr_backup_phase(uint32_t *grp, uint32_t *bit_chk,
                             uint32_t *work_bgn, uint32_t *v, uint32_t *d,
                             uint32_t *p, uint32_t *max_working_cnt)
{
        uint32_t found_begin = 0;
        uint32_t tmp_delay;

        /* Special case code for backing up a phase */
        if (*p == 0) {
                *p = IO_DQS_EN_PHASE_MAX;
                rw_mgr_decr_vfifo(*grp, v);
        } else {
                (*p)--;
        }
        tmp_delay = *work_bgn - IO_DELAY_PER_OPA_TAP;
        scc_mgr_set_dqs_en_phase_all_ranks(*grp, *p);

        for (*d = 0; *d <= IO_DQS_EN_DELAY_MAX && tmp_delay < *work_bgn;
                (*d)++, tmp_delay += IO_DELAY_PER_DQS_EN_DCHAIN_TAP) {
                scc_mgr_set_dqs_en_delay_all_ranks(*grp, *d);

                if (rw_mgr_mem_calibrate_read_test_all_ranks(*grp, 1,
                                                             PASS_ONE_BIT,
                                                             bit_chk, 0)) {
                        found_begin = 1;
                        *work_bgn = tmp_delay;
                        break;
                }
        }

        /* We have found a working dtap before the ptap found above */
        if (found_begin == 1)
                (*max_working_cnt)++;

        /*
         * Restore VFIFO to old state before we decremented it
         * (if needed).
         */
        (*p)++;
        if (*p > IO_DQS_EN_PHASE_MAX) {
                *p = 0;
                rw_mgr_incr_vfifo(*grp, v);
        }

        scc_mgr_set_dqs_en_delay_all_ranks(*grp, 0);
}

static int sdr_nonworking_phase(uint32_t *grp, uint32_t *bit_chk,
                             uint32_t *work_bgn, uint32_t *v, uint32_t *d,
                             uint32_t *p, uint32_t *i, uint32_t *max_working_cnt,
                             uint32_t *work_end)
{
        uint32_t found_end = 0;

        (*p)++;
        *work_end += IO_DELAY_PER_OPA_TAP;
        if (*p > IO_DQS_EN_PHASE_MAX) {
                /* fiddle with FIFO */
                *p = 0;
                rw_mgr_incr_vfifo(*grp, v);
        }

        for (; *i < VFIFO_SIZE + 1; (*i)++) {
                for (; *p <= IO_DQS_EN_PHASE_MAX; (*p)++, *work_end
                        += IO_DELAY_PER_OPA_TAP) {
                        scc_mgr_set_dqs_en_phase_all_ranks(*grp, *p);

                        if (!rw_mgr_mem_calibrate_read_test_all_ranks
                                (*grp, 1, PASS_ONE_BIT, bit_chk, 0)) {
                                found_end = 1;
                                break;
                        } else {
                                (*max_working_cnt)++;
                        }
                }

                if (found_end)
                        break;

                if (*p > IO_DQS_EN_PHASE_MAX) {
                        /* fiddle with FIFO */
                        rw_mgr_incr_vfifo(*grp, v);
                        *p = 0;
                }
        }

        if (*i >= VFIFO_SIZE + 1) {
                /* cannot see edge of failing read */
                debug_cond(DLEVEL == 2, "%s:%d sdr_nonworking_phase: end:\
                           failed\n", __func__, __LINE__);
                return 0;
        } else {
                return 1;
        }
}

static int sdr_find_window_centre(uint32_t *grp, uint32_t *bit_chk,
                                  uint32_t *work_bgn, uint32_t *v, uint32_t *d,
                                  uint32_t *p, uint32_t *work_mid,
                                  uint32_t *work_end)
{
        int i;
        int tmp_delay = 0;

        *work_mid = (*work_bgn + *work_end) / 2;

        debug_cond(DLEVEL == 2, "work_bgn=%d work_end=%d work_mid=%d\n",
                   *work_bgn, *work_end, *work_mid);
        /* Get the middle delay to be less than a VFIFO delay */
        for (*p = 0; *p <= IO_DQS_EN_PHASE_MAX;
                (*p)++, tmp_delay += IO_DELAY_PER_OPA_TAP)
                ;
        debug_cond(DLEVEL == 2, "vfifo ptap delay %d\n", tmp_delay);
        while (*work_mid > tmp_delay)
                *work_mid -= tmp_delay;
        debug_cond(DLEVEL == 2, "new work_mid %d\n", *work_mid);

        tmp_delay = 0;
        for (*p = 0; *p <= IO_DQS_EN_PHASE_MAX && tmp_delay < *work_mid;
                (*p)++, tmp_delay += IO_DELAY_PER_OPA_TAP)
                ;
        tmp_delay -= IO_DELAY_PER_OPA_TAP;
        debug_cond(DLEVEL == 2, "new p %d, tmp_delay=%d\n", (*p) - 1, tmp_delay);
        for (*d = 0; *d <= IO_DQS_EN_DELAY_MAX && tmp_delay < *work_mid; (*d)++,
                tmp_delay += IO_DELAY_PER_DQS_EN_DCHAIN_TAP)
                ;
        debug_cond(DLEVEL == 2, "new d %d, tmp_delay=%d\n", *d, tmp_delay);

        scc_mgr_set_dqs_en_phase_all_ranks(*grp, (*p) - 1);
        scc_mgr_set_dqs_en_delay_all_ranks(*grp, *d);

        /*
         * push vfifo until we can successfully calibrate. We can do this
         * because the largest possible margin in 1 VFIFO cycle.
         */
        for (i = 0; i < VFIFO_SIZE; i++) {
                debug_cond(DLEVEL == 2, "find_dqs_en_phase: center: vfifo=%u\n",
                           *v);
                if (rw_mgr_mem_calibrate_read_test_all_ranks(*grp, 1,
                                                             PASS_ONE_BIT,
                                                             bit_chk, 0)) {
                        break;
                }

                /* fiddle with FIFO */
                rw_mgr_incr_vfifo(*grp, v);
        }

        if (i >= VFIFO_SIZE) {
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: center: \
                           failed\n", __func__, __LINE__);
                return 0;
        } else {
                return 1;
        }
}

/* find a good dqs enable to use */
static uint32_t rw_mgr_mem_calibrate_vfifo_find_dqs_en_phase(uint32_t grp)
{
        uint32_t v, d, p, i;
        uint32_t max_working_cnt;
        uint32_t bit_chk;
        uint32_t dtaps_per_ptap;
        uint32_t work_bgn, work_mid, work_end;
        uint32_t found_passing_read, found_failing_read, initial_failing_dtap;
        uint32_t addr;

        debug("%s:%d %u\n", __func__, __LINE__, grp);

        reg_file_set_sub_stage(CAL_SUBSTAGE_VFIFO_CENTER);

        scc_mgr_set_dqs_en_delay_all_ranks(grp, 0);
        scc_mgr_set_dqs_en_phase_all_ranks(grp, 0);

        /* ************************************************************** */
        /* * Step 0 : Determine number of delay taps for each phase tap * */
        dtaps_per_ptap = IO_DELAY_PER_OPA_TAP/IO_DELAY_PER_DQS_EN_DCHAIN_TAP;

        /* ********************************************************* */
        /* * Step 1 : First push vfifo until we get a failing read * */
        v = find_vfifo_read(grp, &bit_chk);

        max_working_cnt = 0;

        /* ******************************************************** */
        /* * step 2: find first working phase, increment in ptaps * */
        work_bgn = 0;
        if (find_working_phase(&grp, &bit_chk, dtaps_per_ptap, &work_bgn, &v, &d,
                                &p, &i, &max_working_cnt) == 0)
                return 0;

        work_end = work_bgn;

        /*
         * If d is 0 then the working window covers a phase tap and
         * we can follow the old procedure otherwise, we've found the beginning,
         * and we need to increment the dtaps until we find the end.
         */
        if (d == 0) {
                /* ********************************************************* */
                /* * step 3a: if we have room, back off by one and
                increment in dtaps * */

                sdr_backup_phase(&grp, &bit_chk, &work_bgn, &v, &d, &p,
                                 &max_working_cnt);

                /* ********************************************************* */
                /* * step 4a: go forward from working phase to non working
                phase, increment in ptaps * */
                if (sdr_nonworking_phase(&grp, &bit_chk, &work_bgn, &v, &d, &p,
                                         &i, &max_working_cnt, &work_end) == 0)
                        return 0;

                /* ********************************************************* */
                /* * step 5a:  back off one from last, increment in dtaps  * */

                /* Special case code for backing up a phase */
                if (p == 0) {
                        p = IO_DQS_EN_PHASE_MAX;
                        rw_mgr_decr_vfifo(grp, &v);
                } else {
                        p = p - 1;
                }

                work_end -= IO_DELAY_PER_OPA_TAP;
                scc_mgr_set_dqs_en_phase_all_ranks(grp, p);

                /* * The actual increment of dtaps is done outside of
                the if/else loop to share code */
                d = 0;

                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: v/p: \
                           vfifo=%u ptap=%u\n", __func__, __LINE__,
                           v, p);
        } else {
                /* ******************************************************* */
                /* * step 3-5b:  Find the right edge of the window using
                delay taps   * */
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase:vfifo=%u \
                           ptap=%u dtap=%u bgn=%u\n", __func__, __LINE__,
                           v, p, d, work_bgn);

                work_end = work_bgn;

                /* * The actual increment of dtaps is done outside of the
                if/else loop to share code */

                /* Only here to counterbalance a subtract later on which is
                not needed if this branch of the algorithm is taken */
                max_working_cnt++;
        }

        /* The dtap increment to find the failing edge is done here */
        for (; d <= IO_DQS_EN_DELAY_MAX; d++, work_end +=
                IO_DELAY_PER_DQS_EN_DCHAIN_TAP) {
                        debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: \
                                   end-2: dtap=%u\n", __func__, __LINE__, d);
                        scc_mgr_set_dqs_en_delay_all_ranks(grp, d);

                        if (!rw_mgr_mem_calibrate_read_test_all_ranks(grp, 1,
                                                                      PASS_ONE_BIT,
                                                                      &bit_chk, 0)) {
                                break;
                        }
        }

        /* Go back to working dtap */
        if (d != 0)
                work_end -= IO_DELAY_PER_DQS_EN_DCHAIN_TAP;

        debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: v/p/d: vfifo=%u \
                   ptap=%u dtap=%u end=%u\n", __func__, __LINE__,
                   v, p, d-1, work_end);

        if (work_end < work_bgn) {
                /* nil range */
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: end-2: \
                           failed\n", __func__, __LINE__);
                return 0;
        }

        debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: found range [%u,%u]\n",
                   __func__, __LINE__, work_bgn, work_end);

        /* *************************************************************** */
        /*
         * * We need to calculate the number of dtaps that equal a ptap
         * * To do that we'll back up a ptap and re-find the edge of the
         * * window using dtaps
         */

        debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: calculate dtaps_per_ptap \
                   for tracking\n", __func__, __LINE__);

        /* Special case code for backing up a phase */
        if (p == 0) {
                p = IO_DQS_EN_PHASE_MAX;
                rw_mgr_decr_vfifo(grp, &v);
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: backedup \
                           cycle/phase: v=%u p=%u\n", __func__, __LINE__,
                           v, p);
        } else {
                p = p - 1;
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: backedup \
                           phase only: v=%u p=%u", __func__, __LINE__,
                           v, p);
        }

        scc_mgr_set_dqs_en_phase_all_ranks(grp, p);

        /*
         * Increase dtap until we first see a passing read (in case the
         * window is smaller than a ptap),
         * and then a failing read to mark the edge of the window again
         */

        /* Find a passing read */
        debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: find passing read\n",
                   __func__, __LINE__);
        found_passing_read = 0;
        found_failing_read = 0;
        initial_failing_dtap = d;
        for (; d <= IO_DQS_EN_DELAY_MAX; d++) {
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: testing \
                           read d=%u\n", __func__, __LINE__, d);
                scc_mgr_set_dqs_en_delay_all_ranks(grp, d);

                if (rw_mgr_mem_calibrate_read_test_all_ranks(grp, 1,
                                                             PASS_ONE_BIT,
                                                             &bit_chk, 0)) {
                        found_passing_read = 1;
                        break;
                }
        }

        if (found_passing_read) {
                /* Find a failing read */
                debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: find failing \
                           read\n", __func__, __LINE__);
                for (d = d + 1; d <= IO_DQS_EN_DELAY_MAX; d++) {
                        debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: \
                                   testing read d=%u\n", __func__, __LINE__, d);
                        scc_mgr_set_dqs_en_delay_all_ranks(grp, d);

                        if (!rw_mgr_mem_calibrate_read_test_all_ranks
                                (grp, 1, PASS_ONE_BIT, &bit_chk, 0)) {
                                found_failing_read = 1;
                                break;
                        }
                }
        } else {
                debug_cond(DLEVEL == 1, "%s:%d find_dqs_en_phase: failed to \
                           calculate dtaps", __func__, __LINE__);
                debug_cond(DLEVEL == 1, "per ptap. Fall back on static value\n");
        }

        /*
         * The dynamically calculated dtaps_per_ptap is only valid if we
         * found a passing/failing read. If we didn't, it means d hit the max
         * (IO_DQS_EN_DELAY_MAX). Otherwise, dtaps_per_ptap retains its
         * statically calculated value.
         */
        if (found_passing_read && found_failing_read)
                dtaps_per_ptap = d - initial_failing_dtap;

        addr = (u32)&sdr_reg_file->dtaps_per_ptap;
        writel(dtaps_per_ptap, SOCFPGA_SDR_ADDRESS + addr);
        debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: dtaps_per_ptap=%u \
                   - %u = %u",  __func__, __LINE__, d,
                   initial_failing_dtap, dtaps_per_ptap);

        /* ******************************************** */
        /* * step 6:  Find the centre of the window   * */
        if (sdr_find_window_centre(&grp, &bit_chk, &work_bgn, &v, &d, &p,
                                   &work_mid, &work_end) == 0)
                return 0;

        debug_cond(DLEVEL == 2, "%s:%d find_dqs_en_phase: center found: \
                   vfifo=%u ptap=%u dtap=%u\n", __func__, __LINE__,
                   v, p-1, d);
        return 1;
}

/*
 * Try rw_mgr_mem_calibrate_vfifo_find_dqs_en_phase across different
 * dq_in_delay values
 */
static uint32_t
rw_mgr_mem_calibrate_vfifo_find_dqs_en_phase_sweep_dq_in_delay
(uint32_t write_group, uint32_t read_group, uint32_t test_bgn)
{
        uint32_t found;
        uint32_t i;
        uint32_t p;
        uint32_t d;
        uint32_t r;
        uint32_t addr;

        const uint32_t delay_step = IO_IO_IN_DELAY_MAX /
                (RW_MGR_MEM_DQ_PER_READ_DQS-1);
                /* we start at zero, so have one less dq to devide among */

        debug("%s:%d (%u,%u,%u)", __func__, __LINE__, write_group, read_group,
              test_bgn);

        /* try different dq_in_delays since the dq path is shorter than dqs */

        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS;
             r += NUM_RANKS_PER_SHADOW_REG) {
                for (i = 0, p = test_bgn, d = 0; i < RW_MGR_MEM_DQ_PER_READ_DQS;
                        i++, p++, d += delay_step) {
                        debug_cond(DLEVEL == 1, "%s:%d rw_mgr_mem_calibrate_\
                                   vfifo_find_dqs_", __func__, __LINE__);
                        debug_cond(DLEVEL == 1, "en_phase_sweep_dq_in_delay: g=%u/%u ",
                               write_group, read_group);
                        debug_cond(DLEVEL == 1, "r=%u, i=%u p=%u d=%u\n", r, i , p, d);
                        scc_mgr_set_dq_in_delay(write_group, p, d);
                        scc_mgr_load_dq(p);
                }
                addr = (u32)&sdr_scc_mgr->update;
                writel(0, SOCFPGA_SDR_ADDRESS + addr);
        }

        found = rw_mgr_mem_calibrate_vfifo_find_dqs_en_phase(read_group);

        debug_cond(DLEVEL == 1, "%s:%d rw_mgr_mem_calibrate_vfifo_find_dqs_\
                   en_phase_sweep_dq", __func__, __LINE__);
        debug_cond(DLEVEL == 1, "_in_delay: g=%u/%u found=%u; Reseting delay \
                   chain to zero\n", write_group, read_group, found);

        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS;
             r += NUM_RANKS_PER_SHADOW_REG) {
                for (i = 0, p = test_bgn; i < RW_MGR_MEM_DQ_PER_READ_DQS;
                        i++, p++) {
                        scc_mgr_set_dq_in_delay(write_group, p, 0);
                        scc_mgr_load_dq(p);
                }
                addr = (u32)&sdr_scc_mgr->update;
                writel(0, SOCFPGA_SDR_ADDRESS + addr);
        }

        return found;
}

/* per-bit deskew DQ and center */
static uint32_t rw_mgr_mem_calibrate_vfifo_center(uint32_t rank_bgn,
        uint32_t write_group, uint32_t read_group, uint32_t test_bgn,
        uint32_t use_read_test, uint32_t update_fom)
{
        uint32_t i, p, d, min_index;
        /*
         * Store these as signed since there are comparisons with
         * signed numbers.
         */
        uint32_t bit_chk;
        uint32_t sticky_bit_chk;
        int32_t left_edge[RW_MGR_MEM_DQ_PER_READ_DQS];
        int32_t right_edge[RW_MGR_MEM_DQ_PER_READ_DQS];
        int32_t final_dq[RW_MGR_MEM_DQ_PER_READ_DQS];
        int32_t mid;
        int32_t orig_mid_min, mid_min;
        int32_t new_dqs, start_dqs, start_dqs_en, shift_dq, final_dqs,
                final_dqs_en;
        int32_t dq_margin, dqs_margin;
        uint32_t stop;
        uint32_t temp_dq_in_delay1, temp_dq_in_delay2;
        uint32_t addr;

        debug("%s:%d: %u %u", __func__, __LINE__, read_group, test_bgn);

        addr = sdr_get_addr((u32 *)SCC_MGR_DQS_IN_DELAY);
        start_dqs = readl(SOCFPGA_SDR_ADDRESS + addr + (read_group << 2));
        if (IO_SHIFT_DQS_EN_WHEN_SHIFT_DQS)
                start_dqs_en = readl(SOCFPGA_SDR_ADDRESS + addr + ((read_group << 2)
                                     - IO_DQS_EN_DELAY_OFFSET));

        /* set the left and right edge of each bit to an illegal value */
        /* use (IO_IO_IN_DELAY_MAX + 1) as an illegal value */
        sticky_bit_chk = 0;
        for (i = 0; i < RW_MGR_MEM_DQ_PER_READ_DQS; i++) {
                left_edge[i]  = IO_IO_IN_DELAY_MAX + 1;
                right_edge[i] = IO_IO_IN_DELAY_MAX + 1;
        }

        addr = (u32)&sdr_scc_mgr->update;
        /* Search for the left edge of the window for each bit */
        for (d = 0; d <= IO_IO_IN_DELAY_MAX; d++) {
                scc_mgr_apply_group_dq_in_delay(write_group, test_bgn, d);

                writel(0, SOCFPGA_SDR_ADDRESS + addr);

                /*
                 * Stop searching when the read test doesn't pass AND when
                 * we've seen a passing read on every bit.
                 */
                if (use_read_test) {
                        stop = !rw_mgr_mem_calibrate_read_test(rank_bgn,
                                read_group, NUM_READ_PB_TESTS, PASS_ONE_BIT,
                                &bit_chk, 0, 0);
                } else {
                        rw_mgr_mem_calibrate_write_test(rank_bgn, write_group,
                                                        0, PASS_ONE_BIT,
                                                        &bit_chk, 0);
                        bit_chk = bit_chk >> (RW_MGR_MEM_DQ_PER_READ_DQS *
                                (read_group - (write_group *
                                        RW_MGR_MEM_IF_READ_DQS_WIDTH /
                                        RW_MGR_MEM_IF_WRITE_DQS_WIDTH)));
                        stop = (bit_chk == 0);
                }
                sticky_bit_chk = sticky_bit_chk | bit_chk;
                stop = stop && (sticky_bit_chk == param->read_correct_mask);
                debug_cond(DLEVEL == 2, "%s:%d vfifo_center(left): dtap=%u => %u == %u \
                           && %u", __func__, __LINE__, d,
                           sticky_bit_chk,
                        param->read_correct_mask, stop);

                if (stop == 1) {
                        break;
                } else {
                        for (i = 0; i < RW_MGR_MEM_DQ_PER_READ_DQS; i++) {
                                if (bit_chk & 1) {
                                        /* Remember a passing test as the
                                        left_edge */
                                        left_edge[i] = d;
                                } else {
                                        /* If a left edge has not been seen yet,
                                        then a future passing test will mark
                                        this edge as the right edge */
                                        if (left_edge[i] ==
                                                IO_IO_IN_DELAY_MAX + 1) {
                                                right_edge[i] = -(d + 1);
                                        }
                                }
                                bit_chk = bit_chk >> 1;
                        }
                }
        }

        /* Reset DQ delay chains to 0 */
        scc_mgr_apply_group_dq_in_delay(write_group, test_bgn, 0);
        sticky_bit_chk = 0;
        for (i = RW_MGR_MEM_DQ_PER_READ_DQS - 1;; i--) {
                debug_cond(DLEVEL == 2, "%s:%d vfifo_center: left_edge[%u]: \
                           %d right_edge[%u]: %d\n", __func__, __LINE__,
                           i, left_edge[i], i, right_edge[i]);

                /*
                 * Check for cases where we haven't found the left edge,
                 * which makes our assignment of the the right edge invalid.
                 * Reset it to the illegal value.
                 */
                if ((left_edge[i] == IO_IO_IN_DELAY_MAX + 1) && (
                        right_edge[i] != IO_IO_IN_DELAY_MAX + 1)) {
                        right_edge[i] = IO_IO_IN_DELAY_MAX + 1;
                        debug_cond(DLEVEL == 2, "%s:%d vfifo_center: reset \
                                   right_edge[%u]: %d\n", __func__, __LINE__,
                                   i, right_edge[i]);
                }

                /*
                 * Reset sticky bit (except for bits where we have seen
                 * both the left and right edge).
                 */
                sticky_bit_chk = sticky_bit_chk << 1;
                if ((left_edge[i] != IO_IO_IN_DELAY_MAX + 1) &&
                    (right_edge[i] != IO_IO_IN_DELAY_MAX + 1)) {
                        sticky_bit_chk = sticky_bit_chk | 1;
                }

                if (i == 0)
                        break;
        }

        addr = (u32)&sdr_scc_mgr->update;
        /* Search for the right edge of the window for each bit */
        for (d = 0; d <= IO_DQS_IN_DELAY_MAX - start_dqs; d++) {
                scc_mgr_set_dqs_bus_in_delay(read_group, d + start_dqs);
                if (IO_SHIFT_DQS_EN_WHEN_SHIFT_DQS) {
                        uint32_t delay = d + start_dqs_en;
                        if (delay > IO_DQS_EN_DELAY_MAX)
                                delay = IO_DQS_EN_DELAY_MAX;
                        scc_mgr_set_dqs_en_delay(read_group, delay);
                }
                scc_mgr_load_dqs(read_group);

                writel(0, SOCFPGA_SDR_ADDRESS + addr);

                /*
                 * Stop searching when the read test doesn't pass AND when
                 * we've seen a passing read on every bit.
                 */
                if (use_read_test) {
                        stop = !rw_mgr_mem_calibrate_read_test(rank_bgn,
                                read_group, NUM_READ_PB_TESTS, PASS_ONE_BIT,
                                &bit_chk, 0, 0);
                } else {
                        rw_mgr_mem_calibrate_write_test(rank_bgn, write_group,
                                                        0, PASS_ONE_BIT,
                                                        &bit_chk, 0);
                        bit_chk = bit_chk >> (RW_MGR_MEM_DQ_PER_READ_DQS *
                                (read_group - (write_group *
                                        RW_MGR_MEM_IF_READ_DQS_WIDTH /
                                        RW_MGR_MEM_IF_WRITE_DQS_WIDTH)));
                        stop = (bit_chk == 0);
                }
                sticky_bit_chk = sticky_bit_chk | bit_chk;
                stop = stop && (sticky_bit_chk == param->read_correct_mask);

                debug_cond(DLEVEL == 2, "%s:%d vfifo_center(right): dtap=%u => %u == \
                           %u && %u", __func__, __LINE__, d,
                           sticky_bit_chk, param->read_correct_mask, stop);

                if (stop == 1) {
                        break;
                } else {
                        for (i = 0; i < RW_MGR_MEM_DQ_PER_READ_DQS; i++) {
                                if (bit_chk & 1) {
                                        /* Remember a passing test as
                                        the right_edge */
                                        right_edge[i] = d;
                                } else {
                                        if (d != 0) {
                                                /* If a right edge has not been
                                                seen yet, then a future passing
                                                test will mark this edge as the
                                                left edge */
                                                if (right_edge[i] ==
                                                IO_IO_IN_DELAY_MAX + 1) {
                                                        left_edge[i] = -(d + 1);
                                                }
                                        } else {
                                                /* d = 0 failed, but it passed
                                                when testing the left edge,
                                                so it must be marginal,
                                                set it to -1 */
                                                if (right_edge[i] ==
                                                        IO_IO_IN_DELAY_MAX + 1 &&
                                                        left_edge[i] !=
                                                        IO_IO_IN_DELAY_MAX
                                                        + 1) {
                                                        right_edge[i] = -1;
                                                }
                                                /* If a right edge has not been
                                                seen yet, then a future passing
                                                test will mark this edge as the
                                                left edge */
                                                else if (right_edge[i] ==
                                                        IO_IO_IN_DELAY_MAX +
                                                        1) {
                                                        left_edge[i] = -(d + 1);
                                                }
                                        }
                                }

                                debug_cond(DLEVEL == 2, "%s:%d vfifo_center[r,\
                                           d=%u]: ", __func__, __LINE__, d);
                                debug_cond(DLEVEL == 2, "bit_chk_test=%d left_edge[%u]: %d ",
                                           (int)(bit_chk & 1), i, left_edge[i]);
                                debug_cond(DLEVEL == 2, "right_edge[%u]: %d\n", i,
                                           right_edge[i]);
                                bit_chk = bit_chk >> 1;
                        }
                }
        }

        /* Check that all bits have a window */
        addr = (u32)&sdr_scc_mgr->update;
        for (i = 0; i < RW_MGR_MEM_DQ_PER_READ_DQS; i++) {
                debug_cond(DLEVEL == 2, "%s:%d vfifo_center: left_edge[%u]: \
                           %d right_edge[%u]: %d", __func__, __LINE__,
                           i, left_edge[i], i, right_edge[i]);
                if ((left_edge[i] == IO_IO_IN_DELAY_MAX + 1) || (right_edge[i]
                        == IO_IO_IN_DELAY_MAX + 1)) {
                        /*
                         * Restore delay chain settings before letting the loop
                         * in rw_mgr_mem_calibrate_vfifo to retry different
                         * dqs/ck relationships.
                         */
                        scc_mgr_set_dqs_bus_in_delay(read_group, start_dqs);
                        if (IO_SHIFT_DQS_EN_WHEN_SHIFT_DQS) {
                                scc_mgr_set_dqs_en_delay(read_group,
                                                         start_dqs_en);
                        }
                        scc_mgr_load_dqs(read_group);
                        writel(0, SOCFPGA_SDR_ADDRESS + addr);

                        debug_cond(DLEVEL == 1, "%s:%d vfifo_center: failed to \
                                   find edge [%u]: %d %d", __func__, __LINE__,
                                   i, left_edge[i], right_edge[i]);
                        if (use_read_test) {
                                set_failing_group_stage(read_group *
                                        RW_MGR_MEM_DQ_PER_READ_DQS + i,
                                        CAL_STAGE_VFIFO,
                                        CAL_SUBSTAGE_VFIFO_CENTER);
                        } else {
                                set_failing_group_stage(read_group *
                                        RW_MGR_MEM_DQ_PER_READ_DQS + i,
                                        CAL_STAGE_VFIFO_AFTER_WRITES,
                                        CAL_SUBSTAGE_VFIFO_CENTER);
                        }
                        return 0;
                }
        }

        /* Find middle of window for each DQ bit */
        mid_min = left_edge[0] - right_edge[0];
        min_index = 0;
        for (i = 1; i < RW_MGR_MEM_DQ_PER_READ_DQS; i++) {
                mid = left_edge[i] - right_edge[i];
                if (mid < mid_min) {
                        mid_min = mid;
                        min_index = i;
                }
        }

        /*
         * -mid_min/2 represents the amount that we need to move DQS.
         * If mid_min is odd and positive we'll need to add one to
         * make sure the rounding in further calculations is correct
         * (always bias to the right), so just add 1 for all positive values.
         */
        if (mid_min > 0)
                mid_min++;

        mid_min = mid_min / 2;

        debug_cond(DLEVEL == 1, "%s:%d vfifo_center: mid_min=%d (index=%u)\n",
                   __func__, __LINE__, mid_min, min_index);

        /* Determine the amount we can change DQS (which is -mid_min) */
        orig_mid_min = mid_min;
        new_dqs = start_dqs - mid_min;
        if (new_dqs > IO_DQS_IN_DELAY_MAX)
                new_dqs = IO_DQS_IN_DELAY_MAX;
        else if (new_dqs < 0)
                new_dqs = 0;

        mid_min = start_dqs - new_dqs;
        debug_cond(DLEVEL == 1, "vfifo_center: new mid_min=%d new_dqs=%d\n",
                   mid_min, new_dqs);

        if (IO_SHIFT_DQS_EN_WHEN_SHIFT_DQS) {
                if (start_dqs_en - mid_min > IO_DQS_EN_DELAY_MAX)
                        mid_min += start_dqs_en - mid_min - IO_DQS_EN_DELAY_MAX;
                else if (start_dqs_en - mid_min < 0)
                        mid_min += start_dqs_en - mid_min;
        }
        new_dqs = start_dqs - mid_min;

        debug_cond(DLEVEL == 1, "vfifo_center: start_dqs=%d start_dqs_en=%d \
                   new_dqs=%d mid_min=%d\n", start_dqs,
                   IO_SHIFT_DQS_EN_WHEN_SHIFT_DQS ? start_dqs_en : -1,
                   new_dqs, mid_min);

        /* Initialize data for export structures */
        dqs_margin = IO_IO_IN_DELAY_MAX + 1;
        dq_margin  = IO_IO_IN_DELAY_MAX + 1;

        addr = sdr_get_addr((u32 *)SCC_MGR_IO_IN_DELAY);
        /* add delay to bring centre of all DQ windows to the same "level" */
        for (i = 0, p = test_bgn; i < RW_MGR_MEM_DQ_PER_READ_DQS; i++, p++) {
                /* Use values before divide by 2 to reduce round off error */
                shift_dq = (left_edge[i] - right_edge[i] -
                        (left_edge[min_index] - right_edge[min_index]))/2  +
                        (orig_mid_min - mid_min);

                debug_cond(DLEVEL == 2, "vfifo_center: before: \
                           shift_dq[%u]=%d\n", i, shift_dq);

                temp_dq_in_delay1 = readl(SOCFPGA_SDR_ADDRESS + addr + (p << 2));
                temp_dq_in_delay2 = readl(SOCFPGA_SDR_ADDRESS + addr + (i << 2));

                if (shift_dq + (int32_t)temp_dq_in_delay1 >
                        (int32_t)IO_IO_IN_DELAY_MAX) {
                        shift_dq = (int32_t)IO_IO_IN_DELAY_MAX - temp_dq_in_delay2;
                } else if (shift_dq + (int32_t)temp_dq_in_delay1 < 0) {
                        shift_dq = -(int32_t)temp_dq_in_delay1;
                }
                debug_cond(DLEVEL == 2, "vfifo_center: after: \
                           shift_dq[%u]=%d\n", i, shift_dq);
                final_dq[i] = temp_dq_in_delay1 + shift_dq;
                scc_mgr_set_dq_in_delay(write_group, p, final_dq[i]);
                scc_mgr_load_dq(p);

                debug_cond(DLEVEL == 2, "vfifo_center: margin[%u]=[%d,%d]\n", i,
                           left_edge[i] - shift_dq + (-mid_min),
                           right_edge[i] + shift_dq - (-mid_min));
                /* To determine values for export structures */
                if (left_edge[i] - shift_dq + (-mid_min) < dq_margin)
                        dq_margin = left_edge[i] - shift_dq + (-mid_min);

                if (right_edge[i] + shift_dq - (-mid_min) < dqs_margin)
                        dqs_margin = right_edge[i] + shift_dq - (-mid_min);
        }

        final_dqs = new_dqs;
        if (IO_SHIFT_DQS_EN_WHEN_SHIFT_DQS)
                final_dqs_en = start_dqs_en - mid_min;

        /* Move DQS-en */
        if (IO_SHIFT_DQS_EN_WHEN_SHIFT_DQS) {
                scc_mgr_set_dqs_en_delay(read_group, final_dqs_en);
                scc_mgr_load_dqs(read_group);
        }

        /* Move DQS */
        scc_mgr_set_dqs_bus_in_delay(read_group, final_dqs);
        scc_mgr_load_dqs(read_group);
        debug_cond(DLEVEL == 2, "%s:%d vfifo_center: dq_margin=%d \
                   dqs_margin=%d", __func__, __LINE__,
                   dq_margin, dqs_margin);

        /*
         * Do not remove this line as it makes sure all of our decisions
         * have been applied. Apply the update bit.
         */
        addr = (u32)&sdr_scc_mgr->update;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        return (dq_margin >= 0) && (dqs_margin >= 0);
}

/*
 * calibrate the read valid prediction FIFO.
 *
 *  - read valid prediction will consist of finding a good DQS enable phase,
 * DQS enable delay, DQS input phase, and DQS input delay.
 *  - we also do a per-bit deskew on the DQ lines.
 */
static uint32_t rw_mgr_mem_calibrate_vfifo(uint32_t read_group,
                                           uint32_t test_bgn)
{
        uint32_t p, d, rank_bgn, sr;
        uint32_t dtaps_per_ptap;
        uint32_t tmp_delay;
        uint32_t bit_chk;
        uint32_t grp_calibrated;
        uint32_t write_group, write_test_bgn;
        uint32_t failed_substage;

        debug("%s:%d: %u %u\n", __func__, __LINE__, read_group, test_bgn);

        /* update info for sims */
        reg_file_set_stage(CAL_STAGE_VFIFO);

        write_group = read_group;
        write_test_bgn = test_bgn;

        /* USER Determine number of delay taps for each phase tap */
        dtaps_per_ptap = 0;
        tmp_delay = 0;
        while (tmp_delay < IO_DELAY_PER_OPA_TAP) {
                dtaps_per_ptap++;
                tmp_delay += IO_DELAY_PER_DQS_EN_DCHAIN_TAP;
        }
        dtaps_per_ptap--;
        tmp_delay = 0;

        /* update info for sims */
        reg_file_set_group(read_group);

        grp_calibrated = 0;

        reg_file_set_sub_stage(CAL_SUBSTAGE_GUARANTEED_READ);
        failed_substage = CAL_SUBSTAGE_GUARANTEED_READ;

        for (d = 0; d <= dtaps_per_ptap && grp_calibrated == 0; d += 2) {
                /*
                 * In RLDRAMX we may be messing the delay of pins in
                 * the same write group but outside of the current read
                 * the group, but that's ok because we haven't
                 * calibrated output side yet.
                 */
                if (d > 0) {
                        scc_mgr_apply_group_all_out_delay_add_all_ranks
                        (write_group, write_test_bgn, d);
                }

                for (p = 0; p <= IO_DQDQS_OUT_PHASE_MAX && grp_calibrated == 0;
                        p++) {
                        /* set a particular dqdqs phase */
                        scc_mgr_set_dqdqs_output_phase_all_ranks(read_group, p);

                        debug_cond(DLEVEL == 1, "%s:%d calibrate_vfifo: g=%u \
                                   p=%u d=%u\n", __func__, __LINE__,
                                   read_group, p, d);

                        /*
                         * Load up the patterns used by read calibration
                         * using current DQDQS phase.
                         */
                        rw_mgr_mem_calibrate_read_load_patterns(0, 1);
                        if (!(gbl->phy_debug_mode_flags &
                                PHY_DEBUG_DISABLE_GUARANTEED_READ)) {
                                if (!rw_mgr_mem_calibrate_read_test_patterns_all_ranks
                                    (read_group, 1, &bit_chk)) {
                                        debug_cond(DLEVEL == 1, "%s:%d Guaranteed read test failed:",
                                                   __func__, __LINE__);
                                        debug_cond(DLEVEL == 1, " g=%u p=%u d=%u\n",
                                                   read_group, p, d);
                                        break;
                                }
                        }

/* case:56390 */
                        grp_calibrated = 1;
                if (rw_mgr_mem_calibrate_vfifo_find_dqs_en_phase_sweep_dq_in_delay
                    (write_group, read_group, test_bgn)) {
                                /*
                                 * USER Read per-bit deskew can be done on a
                                 * per shadow register basis.
                                 */
                                for (rank_bgn = 0, sr = 0;
                                        rank_bgn < RW_MGR_MEM_NUMBER_OF_RANKS;
                                        rank_bgn += NUM_RANKS_PER_SHADOW_REG,
                                        ++sr) {
                                        /*
                                         * Determine if this set of ranks
                                         * should be skipped entirely.
                                         */
                                        if (!param->skip_shadow_regs[sr]) {
                                                /*
                                                 * If doing read after write
                                                 * calibration, do not update
                                                 * FOM, now - do it then.
                                                 */
                                        if (!rw_mgr_mem_calibrate_vfifo_center
                                                (rank_bgn, write_group,
                                                read_group, test_bgn, 1, 0)) {
                                                        grp_calibrated = 0;
                                                        failed_substage =
                                                CAL_SUBSTAGE_VFIFO_CENTER;
                                                }
                                        }
                                }
                        } else {
                                grp_calibrated = 0;
                                failed_substage = CAL_SUBSTAGE_DQS_EN_PHASE;
                        }
                }
        }

        if (grp_calibrated == 0) {
                set_failing_group_stage(write_group, CAL_STAGE_VFIFO,
                                        failed_substage);
                return 0;
        }

        /*
         * Reset the delay chains back to zero if they have moved > 1
         * (check for > 1 because loop will increase d even when pass in
         * first case).
         */
        if (d > 2)
                scc_mgr_zero_group(write_group, write_test_bgn, 1);

        return 1;
}

/* VFIFO Calibration -- Read Deskew Calibration after write deskew */
static uint32_t rw_mgr_mem_calibrate_vfifo_end(uint32_t read_group,
                                               uint32_t test_bgn)
{
        uint32_t rank_bgn, sr;
        uint32_t grp_calibrated;
        uint32_t write_group;

        debug("%s:%d %u %u", __func__, __LINE__, read_group, test_bgn);

        /* update info for sims */

        reg_file_set_stage(CAL_STAGE_VFIFO_AFTER_WRITES);
        reg_file_set_sub_stage(CAL_SUBSTAGE_VFIFO_CENTER);

        write_group = read_group;

        /* update info for sims */
        reg_file_set_group(read_group);

        grp_calibrated = 1;
        /* Read per-bit deskew can be done on a per shadow register basis */
        for (rank_bgn = 0, sr = 0; rank_bgn < RW_MGR_MEM_NUMBER_OF_RANKS;
                rank_bgn += NUM_RANKS_PER_SHADOW_REG, ++sr) {
                /* Determine if this set of ranks should be skipped entirely */
                if (!param->skip_shadow_regs[sr]) {
                /* This is the last calibration round, update FOM here */
                        if (!rw_mgr_mem_calibrate_vfifo_center(rank_bgn,
                                                                write_group,
                                                                read_group,
                                                                test_bgn, 0,
                                                                1)) {
                                grp_calibrated = 0;
                        }
                }
        }


        if (grp_calibrated == 0) {
                set_failing_group_stage(write_group,
                                        CAL_STAGE_VFIFO_AFTER_WRITES,
                                        CAL_SUBSTAGE_VFIFO_CENTER);
                return 0;
        }

        return 1;
}

/* Calibrate LFIFO to find smallest read latency */
static uint32_t rw_mgr_mem_calibrate_lfifo(void)
{
        uint32_t found_one;
        uint32_t bit_chk;
        uint32_t addr;

        debug("%s:%d\n", __func__, __LINE__);

        /* update info for sims */
        reg_file_set_stage(CAL_STAGE_LFIFO);
        reg_file_set_sub_stage(CAL_SUBSTAGE_READ_LATENCY);

        /* Load up the patterns used by read calibration for all ranks */
        rw_mgr_mem_calibrate_read_load_patterns(0, 1);
        found_one = 0;

        addr = (u32)&phy_mgr_cfg->phy_rlat;
        do {
                writel(gbl->curr_read_lat, SOCFPGA_SDR_ADDRESS + addr);
                debug_cond(DLEVEL == 2, "%s:%d lfifo: read_lat=%u",
                           __func__, __LINE__, gbl->curr_read_lat);

                if (!rw_mgr_mem_calibrate_read_test_all_ranks(0,
                                                              NUM_READ_TESTS,
                                                              PASS_ALL_BITS,
                                                              &bit_chk, 1)) {
                        break;
                }

                found_one = 1;
                /* reduce read latency and see if things are working */
                /* correctly */
                gbl->curr_read_lat--;
        } while (gbl->curr_read_lat > 0);

        /* reset the fifos to get pointers to known state */

        addr = (u32)&phy_mgr_cmd->fifo_reset;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        if (found_one) {
                /* add a fudge factor to the read latency that was determined */
                gbl->curr_read_lat += 2;
                addr = (u32)&phy_mgr_cfg->phy_rlat;
                writel(gbl->curr_read_lat, SOCFPGA_SDR_ADDRESS + addr);
                debug_cond(DLEVEL == 2, "%s:%d lfifo: success: using \
                           read_lat=%u\n", __func__, __LINE__,
                           gbl->curr_read_lat);
                return 1;
        } else {
                set_failing_group_stage(0xff, CAL_STAGE_LFIFO,
                                        CAL_SUBSTAGE_READ_LATENCY);

                debug_cond(DLEVEL == 2, "%s:%d lfifo: failed at initial \
                           read_lat=%u\n", __func__, __LINE__,
                           gbl->curr_read_lat);
                return 0;
        }
}

/*
 * issue write test command.
 * two variants are provided. one that just tests a write pattern and
 * another that tests datamask functionality.
 */
static void rw_mgr_mem_calibrate_write_test_issue(uint32_t group,
                                                  uint32_t test_dm)
{
        uint32_t mcc_instruction;
        uint32_t quick_write_mode = (((STATIC_CALIB_STEPS) & CALIB_SKIP_WRITES) &&
                ENABLE_SUPER_QUICK_CALIBRATION);
        uint32_t rw_wl_nop_cycles;
        uint32_t addr;

        /*
         * Set counter and jump addresses for the right
         * number of NOP cycles.
         * The number of supported NOP cycles can range from -1 to infinity
         * Three different cases are handled:
         *
         * 1. For a number of NOP cycles greater than 0, the RW Mgr looping
         *    mechanism will be used to insert the right number of NOPs
         *
         * 2. For a number of NOP cycles equals to 0, the micro-instruction
         *    issuing the write command will jump straight to the
         *    micro-instruction that turns on DQS (for DDRx), or outputs write
         *    data (for RLD), skipping
         *    the NOP micro-instruction all together
         *
         * 3. A number of NOP cycles equal to -1 indicates that DQS must be
         *    turned on in the same micro-instruction that issues the write
         *    command. Then we need
         *    to directly jump to the micro-instruction that sends out the data
         *
         * NOTE: Implementing this mechanism uses 2 RW Mgr jump-counters
         *       (2 and 3). One jump-counter (0) is used to perform multiple
         *       write-read operations.
         *       one counter left to issue this command in "multiple-group" mode
         */

        rw_wl_nop_cycles = gbl->rw_wl_nop_cycles;

        if (rw_wl_nop_cycles == -1) {
                /*
                 * CNTR 2 - We want to execute the special write operation that
                 * turns on DQS right away and then skip directly to the
                 * instruction that sends out the data. We set the counter to a
                 * large number so that the jump is always taken.
                 */
                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr2;
                writel(0xFF, SOCFPGA_SDR_ADDRESS + addr);

                /* CNTR 3 - Not used */
                if (test_dm) {
                        mcc_instruction = RW_MGR_LFSR_WR_RD_DM_BANK_0_WL_1;
                        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add2;
                        writel(RW_MGR_LFSR_WR_RD_DM_BANK_0_DATA,
                               SOCFPGA_SDR_ADDRESS + addr);
                        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add3;
                        writel(RW_MGR_LFSR_WR_RD_DM_BANK_0_NOP,
                               SOCFPGA_SDR_ADDRESS + addr);
                } else {
                        mcc_instruction = RW_MGR_LFSR_WR_RD_BANK_0_WL_1;
                        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add2;
                        writel(RW_MGR_LFSR_WR_RD_BANK_0_DATA, SOCFPGA_SDR_ADDRESS + addr);
                        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add3;
                        writel(RW_MGR_LFSR_WR_RD_BANK_0_NOP, SOCFPGA_SDR_ADDRESS + addr);
                }
        } else if (rw_wl_nop_cycles == 0) {
                /*
                 * CNTR 2 - We want to skip the NOP operation and go straight
                 * to the DQS enable instruction. We set the counter to a large
                 * number so that the jump is always taken.
                 */
                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr2;
                writel(0xFF, SOCFPGA_SDR_ADDRESS + addr);

                /* CNTR 3 - Not used */
                if (test_dm) {
                        mcc_instruction = RW_MGR_LFSR_WR_RD_DM_BANK_0;
                        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add2;
                        writel(RW_MGR_LFSR_WR_RD_DM_BANK_0_DQS,
                               SOCFPGA_SDR_ADDRESS + addr);
                } else {
                        mcc_instruction = RW_MGR_LFSR_WR_RD_BANK_0;
                        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add2;
                        writel(RW_MGR_LFSR_WR_RD_BANK_0_DQS, SOCFPGA_SDR_ADDRESS + addr);
                }
        } else {
                /*
                 * CNTR 2 - In this case we want to execute the next instruction
                 * and NOT take the jump. So we set the counter to 0. The jump
                 * address doesn't count.
                 */
                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr2;
                writel(0x0, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add2;
                writel(0x0, SOCFPGA_SDR_ADDRESS + addr);

                /*
                 * CNTR 3 - Set the nop counter to the number of cycles we
                 * need to loop for, minus 1.
                 */
                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr3;
                writel(rw_wl_nop_cycles - 1, SOCFPGA_SDR_ADDRESS + addr);
                if (test_dm) {
                        mcc_instruction = RW_MGR_LFSR_WR_RD_DM_BANK_0;
                        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add3;
                        writel(RW_MGR_LFSR_WR_RD_DM_BANK_0_NOP, SOCFPGA_SDR_ADDRESS + addr);
                } else {
                        mcc_instruction = RW_MGR_LFSR_WR_RD_BANK_0;
                        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add3;
                        writel(RW_MGR_LFSR_WR_RD_BANK_0_NOP, SOCFPGA_SDR_ADDRESS + addr);
                }
        }

        addr = sdr_get_addr((u32 *)RW_MGR_RESET_READ_DATAPATH);
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_rw_load_mgr_regs->load_cntr0;
        if (quick_write_mode)
                writel(0x08, SOCFPGA_SDR_ADDRESS + addr);
        else
                writel(0x40, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add0;
        writel(mcc_instruction, SOCFPGA_SDR_ADDRESS + addr);

        /*
         * CNTR 1 - This is used to ensure enough time elapses
         * for read data to come back.
         */
        addr = (u32)&sdr_rw_load_mgr_regs->load_cntr1;
        writel(0x30, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add1;
        if (test_dm) {
                writel(RW_MGR_LFSR_WR_RD_DM_BANK_0_WAIT, SOCFPGA_SDR_ADDRESS + addr);
        } else {
                writel(RW_MGR_LFSR_WR_RD_BANK_0_WAIT, SOCFPGA_SDR_ADDRESS + addr);
        }

        addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
        writel(mcc_instruction, SOCFPGA_SDR_ADDRESS + addr + (group << 2));
}

/* Test writes, can check for a single bit pass or multiple bit pass */
static uint32_t rw_mgr_mem_calibrate_write_test(uint32_t rank_bgn,
        uint32_t write_group, uint32_t use_dm, uint32_t all_correct,
        uint32_t *bit_chk, uint32_t all_ranks)
{
        uint32_t addr;
        uint32_t r;
        uint32_t correct_mask_vg;
        uint32_t tmp_bit_chk;
        uint32_t vg;
        uint32_t rank_end = all_ranks ? RW_MGR_MEM_NUMBER_OF_RANKS :
                (rank_bgn + NUM_RANKS_PER_SHADOW_REG);
        uint32_t addr_rw_mgr;
        uint32_t base_rw_mgr;

        *bit_chk = param->write_correct_mask;
        correct_mask_vg = param->write_correct_mask_vg;

        for (r = rank_bgn; r < rank_end; r++) {
                if (param->skip_ranks[r]) {
                        /* request to skip the rank */
                        continue;
                }

                /* set rank */
                set_rank_and_odt_mask(r, RW_MGR_ODT_MODE_READ_WRITE);

                tmp_bit_chk = 0;
                addr = (u32)&phy_mgr_cmd->fifo_reset;
                addr_rw_mgr = SDR_PHYGRP_RWMGRGRP_ADDRESS;
                for (vg = RW_MGR_MEM_VIRTUAL_GROUPS_PER_WRITE_DQS-1; ; vg--) {
                        /* reset the fifos to get pointers to known state */
                        writel(0, SOCFPGA_SDR_ADDRESS + addr);

                        tmp_bit_chk = tmp_bit_chk <<
                                (RW_MGR_MEM_DQ_PER_WRITE_DQS /
                                RW_MGR_MEM_VIRTUAL_GROUPS_PER_WRITE_DQS);
                        rw_mgr_mem_calibrate_write_test_issue(write_group *
                                RW_MGR_MEM_VIRTUAL_GROUPS_PER_WRITE_DQS+vg,
                                use_dm);

                        base_rw_mgr = readl(SOCFPGA_SDR_ADDRESS + addr_rw_mgr);
                        tmp_bit_chk = tmp_bit_chk | (correct_mask_vg & ~(base_rw_mgr));
                        if (vg == 0)
                                break;
                }
                *bit_chk &= tmp_bit_chk;
        }

        if (all_correct) {
                set_rank_and_odt_mask(0, RW_MGR_ODT_MODE_OFF);
                debug_cond(DLEVEL == 2, "write_test(%u,%u,ALL) : %u == \
                           %u => %lu", write_group, use_dm,
                           *bit_chk, param->write_correct_mask,
                           (long unsigned int)(*bit_chk ==
                           param->write_correct_mask));
                return *bit_chk == param->write_correct_mask;
        } else {
                set_rank_and_odt_mask(0, RW_MGR_ODT_MODE_OFF);
                debug_cond(DLEVEL == 2, "write_test(%u,%u,ONE) : %u != ",
                       write_group, use_dm, *bit_chk);
                debug_cond(DLEVEL == 2, "%lu" " => %lu", (long unsigned int)0,
                        (long unsigned int)(*bit_chk != 0));
                return *bit_chk != 0x00;
        }
}

/*
 * center all windows. do per-bit-deskew to possibly increase size of
 * certain windows.
 */
static uint32_t rw_mgr_mem_calibrate_writes_center(uint32_t rank_bgn,
        uint32_t write_group, uint32_t test_bgn)
{
        uint32_t i, p, min_index;
        int32_t d;
        /*
         * Store these as signed since there are comparisons with
         * signed numbers.
         */
        uint32_t bit_chk;
        uint32_t sticky_bit_chk;
        int32_t left_edge[RW_MGR_MEM_DQ_PER_WRITE_DQS];
        int32_t right_edge[RW_MGR_MEM_DQ_PER_WRITE_DQS];
        int32_t mid;
        int32_t mid_min, orig_mid_min;
        int32_t new_dqs, start_dqs, shift_dq;
        int32_t dq_margin, dqs_margin, dm_margin;
        uint32_t stop;
        uint32_t temp_dq_out1_delay;
        uint32_t addr;

        debug("%s:%d %u %u", __func__, __LINE__, write_group, test_bgn);

        dm_margin = 0;

        addr = sdr_get_addr((u32 *)SCC_MGR_IO_OUT1_DELAY);
        start_dqs = readl(SOCFPGA_SDR_ADDRESS + addr +
                          (RW_MGR_MEM_DQ_PER_WRITE_DQS << 2));

        /* per-bit deskew */

        /*
         * set the left and right edge of each bit to an illegal value
         * use (IO_IO_OUT1_DELAY_MAX + 1) as an illegal value.
         */
        sticky_bit_chk = 0;
        for (i = 0; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++) {
                left_edge[i]  = IO_IO_OUT1_DELAY_MAX + 1;
                right_edge[i] = IO_IO_OUT1_DELAY_MAX + 1;
        }

        /* Search for the left edge of the window for each bit */
        addr = (u32)&sdr_scc_mgr->update;
        for (d = 0; d <= IO_IO_OUT1_DELAY_MAX; d++) {
                scc_mgr_apply_group_dq_out1_delay(write_group, test_bgn, d);

                writel(0, SOCFPGA_SDR_ADDRESS + addr);

                /*
                 * Stop searching when the read test doesn't pass AND when
                 * we've seen a passing read on every bit.
                 */
                stop = !rw_mgr_mem_calibrate_write_test(rank_bgn, write_group,
                        0, PASS_ONE_BIT, &bit_chk, 0);
                sticky_bit_chk = sticky_bit_chk | bit_chk;
                stop = stop && (sticky_bit_chk == param->write_correct_mask);
                debug_cond(DLEVEL == 2, "write_center(left): dtap=%d => %u \
                           == %u && %u [bit_chk= %u ]\n",
                        d, sticky_bit_chk, param->write_correct_mask,
                        stop, bit_chk);

                if (stop == 1) {
                        break;
                } else {
                        for (i = 0; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++) {
                                if (bit_chk & 1) {
                                        /*
                                         * Remember a passing test as the
                                         * left_edge.
                                         */
                                        left_edge[i] = d;
                                } else {
                                        /*
                                         * If a left edge has not been seen
                                         * yet, then a future passing test will
                                         * mark this edge as the right edge.
                                         */
                                        if (left_edge[i] ==
                                                IO_IO_OUT1_DELAY_MAX + 1) {
                                                right_edge[i] = -(d + 1);
                                        }
                                }
                                debug_cond(DLEVEL == 2, "write_center[l,d=%d):", d);
                                debug_cond(DLEVEL == 2, "bit_chk_test=%d left_edge[%u]: %d",
                                           (int)(bit_chk & 1), i, left_edge[i]);
                                debug_cond(DLEVEL == 2, "right_edge[%u]: %d\n", i,
                                       right_edge[i]);
                                bit_chk = bit_chk >> 1;
                        }
                }
        }

        /* Reset DQ delay chains to 0 */
        scc_mgr_apply_group_dq_out1_delay(write_group, test_bgn, 0);
        sticky_bit_chk = 0;
        for (i = RW_MGR_MEM_DQ_PER_WRITE_DQS - 1;; i--) {
                debug_cond(DLEVEL == 2, "%s:%d write_center: left_edge[%u]: \
                           %d right_edge[%u]: %d\n", __func__, __LINE__,
                           i, left_edge[i], i, right_edge[i]);

                /*
                 * Check for cases where we haven't found the left edge,
                 * which makes our assignment of the the right edge invalid.
                 * Reset it to the illegal value.
                 */
                if ((left_edge[i] == IO_IO_OUT1_DELAY_MAX + 1) &&
                    (right_edge[i] != IO_IO_OUT1_DELAY_MAX + 1)) {
                        right_edge[i] = IO_IO_OUT1_DELAY_MAX + 1;
                        debug_cond(DLEVEL == 2, "%s:%d write_center: reset \
                                   right_edge[%u]: %d\n", __func__, __LINE__,
                                   i, right_edge[i]);
                }

                /*
                 * Reset sticky bit (except for bits where we have
                 * seen the left edge).
                 */
                sticky_bit_chk = sticky_bit_chk << 1;
                if ((left_edge[i] != IO_IO_OUT1_DELAY_MAX + 1))
                        sticky_bit_chk = sticky_bit_chk | 1;

                if (i == 0)
                        break;
        }

        /* Search for the right edge of the window for each bit */
        addr = (u32)&sdr_scc_mgr->update;
        for (d = 0; d <= IO_IO_OUT1_DELAY_MAX - start_dqs; d++) {
                scc_mgr_apply_group_dqs_io_and_oct_out1(write_group,
                                                        d + start_dqs);

                writel(0, SOCFPGA_SDR_ADDRESS + addr);

                /*
                 * Stop searching when the read test doesn't pass AND when
                 * we've seen a passing read on every bit.
                 */
                stop = !rw_mgr_mem_calibrate_write_test(rank_bgn, write_group,
                        0, PASS_ONE_BIT, &bit_chk, 0);

                sticky_bit_chk = sticky_bit_chk | bit_chk;
                stop = stop && (sticky_bit_chk == param->write_correct_mask);

                debug_cond(DLEVEL == 2, "write_center (right): dtap=%u => %u == \
                           %u && %u\n", d, sticky_bit_chk,
                           param->write_correct_mask, stop);

                if (stop == 1) {
                        if (d == 0) {
                                for (i = 0; i < RW_MGR_MEM_DQ_PER_WRITE_DQS;
                                        i++) {
                                        /* d = 0 failed, but it passed when
                                        testing the left edge, so it must be
                                        marginal, set it to -1 */
                                        if (right_edge[i] ==
                                                IO_IO_OUT1_DELAY_MAX + 1 &&
                                                left_edge[i] !=
                                                IO_IO_OUT1_DELAY_MAX + 1) {
                                                right_edge[i] = -1;
                                        }
                                }
                        }
                        break;
                } else {
                        for (i = 0; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++) {
                                if (bit_chk & 1) {
                                        /*
                                         * Remember a passing test as
                                         * the right_edge.
                                         */
                                        right_edge[i] = d;
                                } else {
                                        if (d != 0) {
                                                /*
                                                 * If a right edge has not
                                                 * been seen yet, then a future
                                                 * passing test will mark this
                                                 * edge as the left edge.
                                                 */
                                                if (right_edge[i] ==
                                                    IO_IO_OUT1_DELAY_MAX + 1)
                                                        left_edge[i] = -(d + 1);
                                        } else {
                                                /*
                                                 * d = 0 failed, but it passed
                                                 * when testing the left edge,
                                                 * so it must be marginal, set
                                                 * it to -1.
                                                 */
                                                if (right_edge[i] ==
                                                    IO_IO_OUT1_DELAY_MAX + 1 &&
                                                    left_edge[i] !=
                                                    IO_IO_OUT1_DELAY_MAX + 1)
                                                        right_edge[i] = -1;
                                                /*
                                                 * If a right edge has not been
                                                 * seen yet, then a future
                                                 * passing test will mark this
                                                 * edge as the left edge.
                                                 */
                                                else if (right_edge[i] ==
                                                        IO_IO_OUT1_DELAY_MAX +
                                                        1)
                                                        left_edge[i] = -(d + 1);
                                        }
                                }
                                debug_cond(DLEVEL == 2, "write_center[r,d=%d):", d);
                                debug_cond(DLEVEL == 2, "bit_chk_test=%d left_edge[%u]: %d",
                                           (int)(bit_chk & 1), i, left_edge[i]);
                                debug_cond(DLEVEL == 2, "right_edge[%u]: %d\n", i,
                                           right_edge[i]);
                                bit_chk = bit_chk >> 1;
                        }
                }
        }

        /* Check that all bits have a window */
        for (i = 0; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++) {
                debug_cond(DLEVEL == 2, "%s:%d write_center: left_edge[%u]: \
                           %d right_edge[%u]: %d", __func__, __LINE__,
                           i, left_edge[i], i, right_edge[i]);
                if ((left_edge[i] == IO_IO_OUT1_DELAY_MAX + 1) ||
                    (right_edge[i] == IO_IO_OUT1_DELAY_MAX + 1)) {
                        set_failing_group_stage(test_bgn + i,
                                                CAL_STAGE_WRITES,
                                                CAL_SUBSTAGE_WRITES_CENTER);
                        return 0;
                }
        }

        /* Find middle of window for each DQ bit */
        mid_min = left_edge[0] - right_edge[0];
        min_index = 0;
        for (i = 1; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++) {
                mid = left_edge[i] - right_edge[i];
                if (mid < mid_min) {
                        mid_min = mid;
                        min_index = i;
                }
        }

        /*
         * -mid_min/2 represents the amount that we need to move DQS.
         * If mid_min is odd and positive we'll need to add one to
         * make sure the rounding in further calculations is correct
         * (always bias to the right), so just add 1 for all positive values.
         */
        if (mid_min > 0)
                mid_min++;
        mid_min = mid_min / 2;
        debug_cond(DLEVEL == 1, "%s:%d write_center: mid_min=%d\n", __func__,
                   __LINE__, mid_min);

        /* Determine the amount we can change DQS (which is -mid_min) */
        orig_mid_min = mid_min;
        new_dqs = start_dqs;
        mid_min = 0;
        debug_cond(DLEVEL == 1, "%s:%d write_center: start_dqs=%d new_dqs=%d \
                   mid_min=%d\n", __func__, __LINE__, start_dqs, new_dqs, mid_min);
        /* Initialize data for export structures */
        dqs_margin = IO_IO_OUT1_DELAY_MAX + 1;
        dq_margin  = IO_IO_OUT1_DELAY_MAX + 1;

        /* add delay to bring centre of all DQ windows to the same "level" */
        addr = sdr_get_addr((u32 *)SCC_MGR_IO_OUT1_DELAY);
        for (i = 0, p = test_bgn; i < RW_MGR_MEM_DQ_PER_WRITE_DQS; i++, p++) {
                /* Use values before divide by 2 to reduce round off error */
                shift_dq = (left_edge[i] - right_edge[i] -
                        (left_edge[min_index] - right_edge[min_index]))/2  +
                (orig_mid_min - mid_min);

                debug_cond(DLEVEL == 2, "%s:%d write_center: before: shift_dq \
                           [%u]=%d\n", __func__, __LINE__, i, shift_dq);

                temp_dq_out1_delay = readl(SOCFPGA_SDR_ADDRESS + addr + (i << 2));
                if (shift_dq + (int32_t)temp_dq_out1_delay >
                        (int32_t)IO_IO_OUT1_DELAY_MAX) {
                        shift_dq = (int32_t)IO_IO_OUT1_DELAY_MAX - temp_dq_out1_delay;
                } else if (shift_dq + (int32_t)temp_dq_out1_delay < 0) {
                        shift_dq = -(int32_t)temp_dq_out1_delay;
                }
                debug_cond(DLEVEL == 2, "write_center: after: shift_dq[%u]=%d\n",
                           i, shift_dq);
                scc_mgr_set_dq_out1_delay(write_group, i, temp_dq_out1_delay +
                                          shift_dq);
                scc_mgr_load_dq(i);

                debug_cond(DLEVEL == 2, "write_center: margin[%u]=[%d,%d]\n", i,
                           left_edge[i] - shift_dq + (-mid_min),
                           right_edge[i] + shift_dq - (-mid_min));
                /* To determine values for export structures */
                if (left_edge[i] - shift_dq + (-mid_min) < dq_margin)
                        dq_margin = left_edge[i] - shift_dq + (-mid_min);

                if (right_edge[i] + shift_dq - (-mid_min) < dqs_margin)
                        dqs_margin = right_edge[i] + shift_dq - (-mid_min);
        }

        /* Move DQS */
        scc_mgr_apply_group_dqs_io_and_oct_out1(write_group, new_dqs);
        addr = (u32)&sdr_scc_mgr->update;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        /* Centre DM */
        debug_cond(DLEVEL == 2, "%s:%d write_center: DM\n", __func__, __LINE__);

        /*
         * set the left and right edge of each bit to an illegal value,
         * use (IO_IO_OUT1_DELAY_MAX + 1) as an illegal value,
         */
        left_edge[0]  = IO_IO_OUT1_DELAY_MAX + 1;
        right_edge[0] = IO_IO_OUT1_DELAY_MAX + 1;
        int32_t bgn_curr = IO_IO_OUT1_DELAY_MAX + 1;
        int32_t end_curr = IO_IO_OUT1_DELAY_MAX + 1;
        int32_t bgn_best = IO_IO_OUT1_DELAY_MAX + 1;
        int32_t end_best = IO_IO_OUT1_DELAY_MAX + 1;
        int32_t win_best = 0;

        /* Search for the/part of the window with DM shift */
        addr = (u32)&sdr_scc_mgr->update;
        for (d = IO_IO_OUT1_DELAY_MAX; d >= 0; d -= DELTA_D) {
                scc_mgr_apply_group_dm_out1_delay(write_group, d);
                writel(0, SOCFPGA_SDR_ADDRESS + addr);

                if (rw_mgr_mem_calibrate_write_test(rank_bgn, write_group, 1,
                                                    PASS_ALL_BITS, &bit_chk,
                                                    0)) {
                        /* USE Set current end of the window */
                        end_curr = -d;
                        /*
                         * If a starting edge of our window has not been seen
                         * this is our current start of the DM window.
                         */
                        if (bgn_curr == IO_IO_OUT1_DELAY_MAX + 1)
                                bgn_curr = -d;

                        /*
                         * If current window is bigger than best seen.
                         * Set best seen to be current window.
                         */
                        if ((end_curr-bgn_curr+1) > win_best) {
                                win_best = end_curr-bgn_curr+1;
                                bgn_best = bgn_curr;
                                end_best = end_curr;
                        }
                } else {
                        /* We just saw a failing test. Reset temp edge */
                        bgn_curr = IO_IO_OUT1_DELAY_MAX + 1;
                        end_curr = IO_IO_OUT1_DELAY_MAX + 1;
                        }
                }


        /* Reset DM delay chains to 0 */
        scc_mgr_apply_group_dm_out1_delay(write_group, 0);

        /*
         * Check to see if the current window nudges up aganist 0 delay.
         * If so we need to continue the search by shifting DQS otherwise DQS
         * search begins as a new search. */
        if (end_curr != 0) {
                bgn_curr = IO_IO_OUT1_DELAY_MAX + 1;
                end_curr = IO_IO_OUT1_DELAY_MAX + 1;
        }

        /* Search for the/part of the window with DQS shifts */
        addr = (u32)&sdr_scc_mgr->update;
        for (d = 0; d <= IO_IO_OUT1_DELAY_MAX - new_dqs; d += DELTA_D) {
                /*
                 * Note: This only shifts DQS, so are we limiting ourselve to
                 * width of DQ unnecessarily.
                 */
                scc_mgr_apply_group_dqs_io_and_oct_out1(write_group,
                                                        d + new_dqs);

                writel(0, SOCFPGA_SDR_ADDRESS + addr);
                if (rw_mgr_mem_calibrate_write_test(rank_bgn, write_group, 1,
                                                    PASS_ALL_BITS, &bit_chk,
                                                    0)) {
                        /* USE Set current end of the window */
                        end_curr = d;
                        /*
                         * If a beginning edge of our window has not been seen
                         * this is our current begin of the DM window.
                         */
                        if (bgn_curr == IO_IO_OUT1_DELAY_MAX + 1)
                                bgn_curr = d;

                        /*
                         * If current window is bigger than best seen. Set best
                         * seen to be current window.
                         */
                        if ((end_curr-bgn_curr+1) > win_best) {
                                win_best = end_curr-bgn_curr+1;
                                bgn_best = bgn_curr;
                                end_best = end_curr;
                        }
                } else {
                        /* We just saw a failing test. Reset temp edge */
                        bgn_curr = IO_IO_OUT1_DELAY_MAX + 1;
                        end_curr = IO_IO_OUT1_DELAY_MAX + 1;

                        /* Early exit optimization: if ther remaining delay
                        chain space is less than already seen largest window
                        we can exit */
                        if ((win_best-1) >
                                (IO_IO_OUT1_DELAY_MAX - new_dqs - d)) {
                                        break;
                                }
                        }
                }

        /* assign left and right edge for cal and reporting; */
        left_edge[0] = -1*bgn_best;
        right_edge[0] = end_best;

        debug_cond(DLEVEL == 2, "%s:%d dm_calib: left=%d right=%d\n", __func__,
                   __LINE__, left_edge[0], right_edge[0]);

        /* Move DQS (back to orig) */
        scc_mgr_apply_group_dqs_io_and_oct_out1(write_group, new_dqs);

        /* Move DM */

        /* Find middle of window for the DM bit */
        mid = (left_edge[0] - right_edge[0]) / 2;

        /* only move right, since we are not moving DQS/DQ */
        if (mid < 0)
                mid = 0;

        /* dm_marign should fail if we never find a window */
        if (win_best == 0)
                dm_margin = -1;
        else
                dm_margin = left_edge[0] - mid;

        scc_mgr_apply_group_dm_out1_delay(write_group, mid);
        addr = (u32)&sdr_scc_mgr->update;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        debug_cond(DLEVEL == 2, "%s:%d dm_calib: left=%d right=%d mid=%d \
                   dm_margin=%d\n", __func__, __LINE__, left_edge[0],
                   right_edge[0], mid, dm_margin);
        /* Export values */
        gbl->fom_out += dq_margin + dqs_margin;

        debug_cond(DLEVEL == 2, "%s:%d write_center: dq_margin=%d \
                   dqs_margin=%d dm_margin=%d\n", __func__, __LINE__,
                   dq_margin, dqs_margin, dm_margin);

        /*
         * Do not remove this line as it makes sure all of our
         * decisions have been applied.
         */
        addr = (u32)&sdr_scc_mgr->update;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);
        return (dq_margin >= 0) && (dqs_margin >= 0) && (dm_margin >= 0);
}

/* calibrate the write operations */
static uint32_t rw_mgr_mem_calibrate_writes(uint32_t rank_bgn, uint32_t g,
        uint32_t test_bgn)
{
        /* update info for sims */
        debug("%s:%d %u %u\n", __func__, __LINE__, g, test_bgn);

        reg_file_set_stage(CAL_STAGE_WRITES);
        reg_file_set_sub_stage(CAL_SUBSTAGE_WRITES_CENTER);

        reg_file_set_group(g);

        if (!rw_mgr_mem_calibrate_writes_center(rank_bgn, g, test_bgn)) {
                set_failing_group_stage(g, CAL_STAGE_WRITES,
                                        CAL_SUBSTAGE_WRITES_CENTER);
                return 0;
        }

        return 1;
}

/* precharge all banks and activate row 0 in bank "000..." and bank "111..." */
static void mem_precharge_and_activate(void)
{
        uint32_t r;
        uint32_t addr;

        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS; r++) {
                if (param->skip_ranks[r]) {
                        /* request to skip the rank */
                        continue;
                }

                /* set rank */
                set_rank_and_odt_mask(r, RW_MGR_ODT_MODE_OFF);

                /* precharge all banks ... */
                addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                writel(RW_MGR_PRECHARGE_ALL, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr0;
                writel(0x0F, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add0;
                writel(RW_MGR_ACTIVATE_0_AND_1_WAIT1, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&sdr_rw_load_mgr_regs->load_cntr1;
                writel(0x0F, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_rw_load_jump_mgr_regs->load_jump_add1;
                writel(RW_MGR_ACTIVATE_0_AND_1_WAIT2, SOCFPGA_SDR_ADDRESS + addr);

                /* activate rows */
                addr = sdr_get_addr((u32 *)RW_MGR_RUN_SINGLE_GROUP);
                writel(RW_MGR_ACTIVATE_0_AND_1, SOCFPGA_SDR_ADDRESS + addr);
        }
}

/* Configure various memory related parameters. */
static void mem_config(void)
{
        uint32_t rlat, wlat;
        uint32_t rw_wl_nop_cycles;
        uint32_t max_latency;
        uint32_t addr;

        debug("%s:%d\n", __func__, __LINE__);
        /* read in write and read latency */
        addr = sdr_get_addr(&data_mgr->t_wl_add);
        wlat = readl(SOCFPGA_SDR_ADDRESS + addr);

        addr = sdr_get_addr(&data_mgr->mem_t_add);
        wlat += readl(SOCFPGA_SDR_ADDRESS + addr);
        /* WL for hard phy does not include additive latency */

        /*
         * add addtional write latency to offset the address/command extra
         * clock cycle. We change the AC mux setting causing AC to be delayed
         * by one mem clock cycle. Only do this for DDR3
         */
        wlat = wlat + 1;

        addr = sdr_get_addr(&data_mgr->t_rl_add);
        rlat = readl(SOCFPGA_SDR_ADDRESS + addr);

        rw_wl_nop_cycles = wlat - 2;
        gbl->rw_wl_nop_cycles = rw_wl_nop_cycles;

        /*
         * For AV/CV, lfifo is hardened and always runs at full rate so
         * max latency in AFI clocks, used here, is correspondingly smaller.
         */
        max_latency = (1<<MAX_LATENCY_COUNT_WIDTH)/1 - 1;
        /* configure for a burst length of 8 */

        /* write latency */
        /* Adjust Write Latency for Hard PHY */
        wlat = wlat + 1;

        /* set a pretty high read latency initially */
        gbl->curr_read_lat = rlat + 16;

        if (gbl->curr_read_lat > max_latency)
                gbl->curr_read_lat = max_latency;

        addr = (u32)&phy_mgr_cfg->phy_rlat;
        writel(gbl->curr_read_lat, SOCFPGA_SDR_ADDRESS + addr);

        /* advertise write latency */
        gbl->curr_write_lat = wlat;
        addr = (u32)&phy_mgr_cfg->afi_wlat;
        writel(wlat - 2, SOCFPGA_SDR_ADDRESS + addr);

        /* initialize bit slips */
        mem_precharge_and_activate();
}

/* Set VFIFO and LFIFO to instant-on settings in skip calibration mode */
static void mem_skip_calibrate(void)
{
        uint32_t vfifo_offset;
        uint32_t i, j, r;
        uint32_t addr;

        debug("%s:%d\n", __func__, __LINE__);
        /* Need to update every shadow register set used by the interface */
        for (r = 0; r < RW_MGR_MEM_NUMBER_OF_RANKS;
                r += NUM_RANKS_PER_SHADOW_REG) {
                /*
                 * Set output phase alignment settings appropriate for
                 * skip calibration.
                 */
                for (i = 0; i < RW_MGR_MEM_IF_READ_DQS_WIDTH; i++) {
                        scc_mgr_set_dqs_en_phase(i, 0);
#if IO_DLL_CHAIN_LENGTH == 6
                        scc_mgr_set_dqdqs_output_phase(i, 6);
#else
                        scc_mgr_set_dqdqs_output_phase(i, 7);
#endif
                        /*
                         * Case:33398
                         *
                         * Write data arrives to the I/O two cycles before write
                         * latency is reached (720 deg).
                         *   -> due to bit-slip in a/c bus
                         *   -> to allow board skew where dqs is longer than ck
                         *      -> how often can this happen!?
                         *      -> can claim back some ptaps for high freq
                         *       support if we can relax this, but i digress...
                         *
                         * The write_clk leads mem_ck by 90 deg
                         * The minimum ptap of the OPA is 180 deg
                         * Each ptap has (360 / IO_DLL_CHAIN_LENGH) deg of delay
                         * The write_clk is always delayed by 2 ptaps
                         *
                         * Hence, to make DQS aligned to CK, we need to delay
                         * DQS by:
                         *    (720 - 90 - 180 - 2 * (360 / IO_DLL_CHAIN_LENGTH))
                         *
                         * Dividing the above by (360 / IO_DLL_CHAIN_LENGTH)
                         * gives us the number of ptaps, which simplies to:
                         *
                         *    (1.25 * IO_DLL_CHAIN_LENGTH - 2)
                         */
                        scc_mgr_set_dqdqs_output_phase(i, (1.25 *
                                IO_DLL_CHAIN_LENGTH - 2));
                }
                addr = (u32)&sdr_scc_mgr->dqs_ena;
                writel(0xff, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_scc_mgr->dqs_io_ena;
                writel(0xff, SOCFPGA_SDR_ADDRESS + addr);

                addr = sdr_get_addr((u32 *)SCC_MGR_GROUP_COUNTER);
                for (i = 0; i < RW_MGR_MEM_IF_WRITE_DQS_WIDTH; i++) {
                        writel(i, SOCFPGA_SDR_ADDRESS + addr);
                }
                addr = (u32)&sdr_scc_mgr->dq_ena;
                writel(0xff, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_scc_mgr->dm_ena;
                writel(0xff, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&sdr_scc_mgr->update;
                writel(0, SOCFPGA_SDR_ADDRESS + addr);
        }

        /* Compensate for simulation model behaviour */
        for (i = 0; i < RW_MGR_MEM_IF_READ_DQS_WIDTH; i++) {
                scc_mgr_set_dqs_bus_in_delay(i, 10);
                scc_mgr_load_dqs(i);
        }
        addr = (u32)&sdr_scc_mgr->update;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        /*
         * ArriaV has hard FIFOs that can only be initialized by incrementing
         * in sequencer.
         */
        vfifo_offset = CALIB_VFIFO_OFFSET;
        addr = (u32)&phy_mgr_cmd->inc_vfifo_hard_phy;
        for (j = 0; j < vfifo_offset; j++) {
                writel(0xff, SOCFPGA_SDR_ADDRESS + addr);
        }
        addr = (u32)&phy_mgr_cmd->fifo_reset;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        /*
         * For ACV with hard lfifo, we get the skip-cal setting from
         * generation-time constant.
         */
        gbl->curr_read_lat = CALIB_LFIFO_OFFSET;
        addr = (u32)&phy_mgr_cfg->phy_rlat;
        writel(gbl->curr_read_lat, SOCFPGA_SDR_ADDRESS + addr);
}

/* Memory calibration entry point */
static uint32_t mem_calibrate(void)
{
        uint32_t i;
        uint32_t rank_bgn, sr;
        uint32_t write_group, write_test_bgn;
        uint32_t read_group, read_test_bgn;
        uint32_t run_groups, current_run;
        uint32_t failing_groups = 0;
        uint32_t group_failed = 0;
        uint32_t sr_failed = 0;
        uint32_t addr;

        debug("%s:%d\n", __func__, __LINE__);
        /* Initialize the data settings */

        gbl->error_substage = CAL_SUBSTAGE_NIL;
        gbl->error_stage = CAL_STAGE_NIL;
        gbl->error_group = 0xff;
        gbl->fom_in = 0;
        gbl->fom_out = 0;

        mem_config();

        uint32_t bypass_mode = 0x1;
        addr = sdr_get_addr((u32 *)SCC_MGR_GROUP_COUNTER);
        for (i = 0; i < RW_MGR_MEM_IF_READ_DQS_WIDTH; i++) {
                writel(i, SOCFPGA_SDR_ADDRESS + addr);
                scc_set_bypass_mode(i, bypass_mode);
        }

        if ((dyn_calib_steps & CALIB_SKIP_ALL) == CALIB_SKIP_ALL) {
                /*
                 * Set VFIFO and LFIFO to instant-on settings in skip
                 * calibration mode.
                 */
                mem_skip_calibrate();
        } else {
                for (i = 0; i < NUM_CALIB_REPEAT; i++) {
                        /*
                         * Zero all delay chain/phase settings for all
                         * groups and all shadow register sets.
                         */
                        scc_mgr_zero_all();

                        run_groups = ~param->skip_groups;

                        for (write_group = 0, write_test_bgn = 0; write_group
                                < RW_MGR_MEM_IF_WRITE_DQS_WIDTH; write_group++,
                                write_test_bgn += RW_MGR_MEM_DQ_PER_WRITE_DQS) {
                                /* Initialized the group failure */
                                group_failed = 0;

                                current_run = run_groups & ((1 <<
                                        RW_MGR_NUM_DQS_PER_WRITE_GROUP) - 1);
                                run_groups = run_groups >>
                                        RW_MGR_NUM_DQS_PER_WRITE_GROUP;

                                if (current_run == 0)
                                        continue;

                                addr = sdr_get_addr((u32 *)SCC_MGR_GROUP_COUNTER);
                                writel(write_group, SOCFPGA_SDR_ADDRESS + addr);
                                scc_mgr_zero_group(write_group, write_test_bgn,
                                                   0);

                                for (read_group = write_group *
                                        RW_MGR_MEM_IF_READ_DQS_WIDTH /
                                        RW_MGR_MEM_IF_WRITE_DQS_WIDTH,
                                        read_test_bgn = 0;
                                        read_group < (write_group + 1) *
                                        RW_MGR_MEM_IF_READ_DQS_WIDTH /
                                        RW_MGR_MEM_IF_WRITE_DQS_WIDTH &&
                                        group_failed == 0;
                                        read_group++, read_test_bgn +=
                                        RW_MGR_MEM_DQ_PER_READ_DQS) {
                                        /* Calibrate the VFIFO */
                                        if (!((STATIC_CALIB_STEPS) &
                                                CALIB_SKIP_VFIFO)) {
                                                if (!rw_mgr_mem_calibrate_vfifo
                                                        (read_group,
                                                        read_test_bgn)) {
                                                        group_failed = 1;

                                                        if (!(gbl->
                                                        phy_debug_mode_flags &
                                                PHY_DEBUG_SWEEP_ALL_GROUPS)) {
                                                                return 0;
                                                        }
                                                }
                                        }
                                }

                                /* Calibrate the output side */
                                if (group_failed == 0)  {
                                        for (rank_bgn = 0, sr = 0; rank_bgn
                                                < RW_MGR_MEM_NUMBER_OF_RANKS;
                                                rank_bgn +=
                                                NUM_RANKS_PER_SHADOW_REG,
                                                ++sr) {
                                                sr_failed = 0;
                                                if (!((STATIC_CALIB_STEPS) &
                                                CALIB_SKIP_WRITES)) {
                                                        if ((STATIC_CALIB_STEPS)
                                                & CALIB_SKIP_DELAY_SWEEPS) {
                                                /* not needed in quick mode! */
                                                        } else {
                                                /*
                                                 * Determine if this set of
                                                 * ranks should be skipped
                                                 * entirely.
                                                 */
                                        if (!param->skip_shadow_regs[sr]) {
                                                if (!rw_mgr_mem_calibrate_writes
                                                (rank_bgn, write_group,
                                                write_test_bgn)) {
                                                        sr_failed = 1;
                                                        if (!(gbl->
                                                        phy_debug_mode_flags &
                                                PHY_DEBUG_SWEEP_ALL_GROUPS)) {
                                                                return 0;
                                                                        }
                                                                        }
                                                                }
                                                        }
                                                }
                                                if (sr_failed != 0)
                                                        group_failed = 1;
                                        }
                                }

                                if (group_failed == 0) {
                                        for (read_group = write_group *
                                        RW_MGR_MEM_IF_READ_DQS_WIDTH /
                                        RW_MGR_MEM_IF_WRITE_DQS_WIDTH,
                                        read_test_bgn = 0;
                                                read_group < (write_group + 1)
                                                * RW_MGR_MEM_IF_READ_DQS_WIDTH
                                                / RW_MGR_MEM_IF_WRITE_DQS_WIDTH &&
                                                group_failed == 0;
                                                read_group++, read_test_bgn +=
                                                RW_MGR_MEM_DQ_PER_READ_DQS) {
                                                if (!((STATIC_CALIB_STEPS) &
                                                        CALIB_SKIP_WRITES)) {
                                        if (!rw_mgr_mem_calibrate_vfifo_end
                                                (read_group, read_test_bgn)) {
                                                        group_failed = 1;

                                                if (!(gbl->phy_debug_mode_flags
                                                & PHY_DEBUG_SWEEP_ALL_GROUPS)) {
                                                                return 0;
                                                                }
                                                        }
                                                }
                                        }
                                }

                                if (group_failed != 0)
                                        failing_groups++;
                        }

                        /*
                         * USER If there are any failing groups then report
                         * the failure.
                         */
                        if (failing_groups != 0)
                                return 0;

                        /* Calibrate the LFIFO */
                        if (!((STATIC_CALIB_STEPS) & CALIB_SKIP_LFIFO)) {
                                /*
                                 * If we're skipping groups as part of debug,
                                 * don't calibrate LFIFO.
                                 */
                                if (param->skip_groups == 0) {
                                        if (!rw_mgr_mem_calibrate_lfifo())
                                                return 0;
                                }
                        }
                }
        }

        /*
         * Do not remove this line as it makes sure all of our decisions
         * have been applied.
         */
        addr = (u32)&sdr_scc_mgr->update;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);
        return 1;
}

static uint32_t run_mem_calibrate(void)
{
        uint32_t pass;
        uint32_t debug_info;
        uint32_t addr;

        debug("%s:%d\n", __func__, __LINE__);

        /* Reset pass/fail status shown on afi_cal_success/fail */
        addr = (u32)&phy_mgr_cfg->cal_status;
        writel(PHY_MGR_CAL_RESET, SOCFPGA_SDR_ADDRESS + addr);

        addr = sdr_get_addr((u32 *)BASE_MMR);
        /* stop tracking manger */
        uint32_t ctrlcfg = readl(SOCFPGA_SDR_ADDRESS + addr);

        addr = sdr_get_addr((u32 *)BASE_MMR);
        writel(ctrlcfg & 0xFFBFFFFF, SOCFPGA_SDR_ADDRESS + addr);

        initialize();
        rw_mgr_mem_initialize();

        pass = mem_calibrate();

        mem_precharge_and_activate();
        addr = (u32)&phy_mgr_cmd->fifo_reset;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        /*
         * Handoff:
         * Don't return control of the PHY back to AFI when in debug mode.
         */
        if ((gbl->phy_debug_mode_flags & PHY_DEBUG_IN_DEBUG_MODE) == 0) {
                rw_mgr_mem_handoff();
                /*
                 * In Hard PHY this is a 2-bit control:
                 * 0: AFI Mux Select
                 * 1: DDIO Mux Select
                 */
                addr = (u32)&phy_mgr_cfg->mux_sel;
                writel(0x2, SOCFPGA_SDR_ADDRESS + addr);
        }

        addr = sdr_get_addr((u32 *)BASE_MMR);
        writel(ctrlcfg, SOCFPGA_SDR_ADDRESS + addr);

        if (pass) {
                printf("%s: CALIBRATION PASSED\n", __FILE__);

                gbl->fom_in /= 2;
                gbl->fom_out /= 2;

                if (gbl->fom_in > 0xff)
                        gbl->fom_in = 0xff;

                if (gbl->fom_out > 0xff)
                        gbl->fom_out = 0xff;

                /* Update the FOM in the register file */
                debug_info = gbl->fom_in;
                debug_info |= gbl->fom_out << 8;
                addr = (u32)&sdr_reg_file->fom;
                writel(debug_info, SOCFPGA_SDR_ADDRESS + addr);

                addr = (u32)&phy_mgr_cfg->cal_debug_info;
                writel(debug_info, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&phy_mgr_cfg->cal_status;
                writel(PHY_MGR_CAL_SUCCESS, SOCFPGA_SDR_ADDRESS + addr);
        } else {
                printf("%s: CALIBRATION FAILED\n", __FILE__);

                debug_info = gbl->error_stage;
                debug_info |= gbl->error_substage << 8;
                debug_info |= gbl->error_group << 16;

                addr = (u32)&sdr_reg_file->failing_stage;
                writel(debug_info, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&phy_mgr_cfg->cal_debug_info;
                writel(debug_info, SOCFPGA_SDR_ADDRESS + addr);
                addr = (u32)&phy_mgr_cfg->cal_status;
                writel(PHY_MGR_CAL_FAIL, SOCFPGA_SDR_ADDRESS + addr);

                /* Update the failing group/stage in the register file */
                debug_info = gbl->error_stage;
                debug_info |= gbl->error_substage << 8;
                debug_info |= gbl->error_group << 16;
                addr = (u32)&sdr_reg_file->failing_stage;
                writel(debug_info, SOCFPGA_SDR_ADDRESS + addr);
        }

        return pass;
}

static void hc_initialize_rom_data(void)
{
        uint32_t i;
        uint32_t addr;

        addr = sdr_get_addr((u32 *)(RW_MGR_INST_ROM_WRITE));
        for (i = 0; i < ARRAY_SIZE(inst_rom_init); i++) {
                uint32_t data = inst_rom_init[i];
                writel(data, SOCFPGA_SDR_ADDRESS + addr + (i << 2));
        }

        addr = sdr_get_addr((u32 *)(RW_MGR_AC_ROM_WRITE));
        for (i = 0; i < ARRAY_SIZE(ac_rom_init); i++) {
                uint32_t data = ac_rom_init[i];
                writel(data, SOCFPGA_SDR_ADDRESS + addr + (i << 2));
        }
}

static void initialize_reg_file(void)
{
        uint32_t addr;

        /* Initialize the register file with the correct data */
        addr = (u32)&sdr_reg_file->signature;
        writel(REG_FILE_INIT_SEQ_SIGNATURE, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->debug_data_addr;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->cur_stage;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->fom;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->failing_stage;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->debug1;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->debug2;
        writel(0, SOCFPGA_SDR_ADDRESS + addr);
}

static void initialize_hps_phy(void)
{
        uint32_t reg;
        uint32_t addr;
        /*
         * Tracking also gets configured here because it's in the
         * same register.
         */
        uint32_t trk_sample_count = 7500;
        uint32_t trk_long_idle_sample_count = (10 << 16) | 100;
        /*
         * Format is number of outer loops in the 16 MSB, sample
         * count in 16 LSB.
         */

        reg = 0;
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_ACDELAYEN_SET(2);
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_DQDELAYEN_SET(1);
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_DQSDELAYEN_SET(1);
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_DQSLOGICDELAYEN_SET(1);
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_RESETDELAYEN_SET(0);
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_LPDDRDIS_SET(1);
        /*
         * This field selects the intrinsic latency to RDATA_EN/FULL path.
         * 00-bypass, 01- add 5 cycles, 10- add 10 cycles, 11- add 15 cycles.
         */
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_ADDLATSEL_SET(0);
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_SAMPLECOUNT_19_0_SET(
                trk_sample_count);
        addr = sdr_get_addr((u32 *)BASE_MMR);
        writel(reg, SOCFPGA_SDR_ADDRESS + addr + SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_OFFSET);

        reg = 0;
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_1_SAMPLECOUNT_31_20_SET(
                trk_sample_count >>
                SDR_CTRLGRP_PHYCTRL_PHYCTRL_0_SAMPLECOUNT_19_0_WIDTH);
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_1_LONGIDLESAMPLECOUNT_19_0_SET(
                trk_long_idle_sample_count);
        writel(reg, SOCFPGA_SDR_ADDRESS + addr + SDR_CTRLGRP_PHYCTRL_PHYCTRL_1_OFFSET);

        reg = 0;
        reg |= SDR_CTRLGRP_PHYCTRL_PHYCTRL_2_LONGIDLESAMPLECOUNT_31_20_SET(
                trk_long_idle_sample_count >>
                SDR_CTRLGRP_PHYCTRL_PHYCTRL_1_LONGIDLESAMPLECOUNT_19_0_WIDTH);
        writel(reg, SOCFPGA_SDR_ADDRESS + addr + SDR_CTRLGRP_PHYCTRL_PHYCTRL_2_OFFSET);
}

static void initialize_tracking(void)
{
        uint32_t concatenated_longidle = 0x0;
        uint32_t concatenated_delays = 0x0;
        uint32_t concatenated_rw_addr = 0x0;
        uint32_t concatenated_refresh = 0x0;
        uint32_t trk_sample_count = 7500;
        uint32_t dtaps_per_ptap;
        uint32_t tmp_delay;
        uint32_t addr;

        /*
         * compute usable version of value in case we skip full
         * computation later
         */
        dtaps_per_ptap = 0;
        tmp_delay = 0;
        while (tmp_delay < IO_DELAY_PER_OPA_TAP) {
                dtaps_per_ptap++;
                tmp_delay += IO_DELAY_PER_DCHAIN_TAP;
        }
        dtaps_per_ptap--;

        concatenated_longidle = concatenated_longidle ^ 10;
                /*longidle outer loop */
        concatenated_longidle = concatenated_longidle << 16;
        concatenated_longidle = concatenated_longidle ^ 100;
                /*longidle sample count */
        concatenated_delays = concatenated_delays ^ 243;
                /* trfc, worst case of 933Mhz 4Gb */
        concatenated_delays = concatenated_delays << 8;
        concatenated_delays = concatenated_delays ^ 14;
                /* trcd, worst case */
        concatenated_delays = concatenated_delays << 8;
        concatenated_delays = concatenated_delays ^ 10;
                /* vfifo wait */
        concatenated_delays = concatenated_delays << 8;
        concatenated_delays = concatenated_delays ^ 4;
                /* mux delay */

        concatenated_rw_addr = concatenated_rw_addr ^ RW_MGR_IDLE;
        concatenated_rw_addr = concatenated_rw_addr << 8;
        concatenated_rw_addr = concatenated_rw_addr ^ RW_MGR_ACTIVATE_1;
        concatenated_rw_addr = concatenated_rw_addr << 8;
        concatenated_rw_addr = concatenated_rw_addr ^ RW_MGR_SGLE_READ;
        concatenated_rw_addr = concatenated_rw_addr << 8;
        concatenated_rw_addr = concatenated_rw_addr ^ RW_MGR_PRECHARGE_ALL;

        concatenated_refresh = concatenated_refresh ^ RW_MGR_REFRESH_ALL;
        concatenated_refresh = concatenated_refresh << 24;
        concatenated_refresh = concatenated_refresh ^ 1000; /* trefi */

        /* Initialize the register file with the correct data */
        addr = (u32)&sdr_reg_file->dtaps_per_ptap;
        writel(dtaps_per_ptap, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->trk_sample_count;
        writel(trk_sample_count, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->trk_longidle;
        writel(concatenated_longidle, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->delays;
        writel(concatenated_delays, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->trk_rw_mgr_addr;
        writel(concatenated_rw_addr, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->trk_read_dqs_width;
        writel(RW_MGR_MEM_IF_READ_DQS_WIDTH, SOCFPGA_SDR_ADDRESS + addr);

        addr = (u32)&sdr_reg_file->trk_rfsh;
        writel(concatenated_refresh, SOCFPGA_SDR_ADDRESS + addr);
}

int sdram_calibration_full(void)
{
        struct param_type my_param;
        struct gbl_type my_gbl;
        uint32_t pass;
        uint32_t i;

        param = &my_param;
        gbl = &my_gbl;

        /* Initialize the debug mode flags */
        gbl->phy_debug_mode_flags = 0;
        /* Set the calibration enabled by default */
        gbl->phy_debug_mode_flags |= PHY_DEBUG_ENABLE_CAL_RPT;
        /*
         * Only sweep all groups (regardless of fail state) by default
         * Set enabled read test by default.
         */
#if DISABLE_GUARANTEED_READ
        gbl->phy_debug_mode_flags |= PHY_DEBUG_DISABLE_GUARANTEED_READ;
#endif
        /* Initialize the register file */
        initialize_reg_file();

        /* Initialize any PHY CSR */
        initialize_hps_phy();

        scc_mgr_initialize();

        initialize_tracking();

        /* USER Enable all ranks, groups */
        for (i = 0; i < RW_MGR_MEM_NUMBER_OF_RANKS; i++)
                param->skip_ranks[i] = 0;
        for (i = 0; i < NUM_SHADOW_REGS; ++i)
                param->skip_shadow_regs[i] = 0;
        param->skip_groups = 0;

        printf("%s: Preparing to start memory calibration\n", __FILE__);

        debug("%s:%d\n", __func__, __LINE__);
        debug_cond(DLEVEL == 1,
                   "DDR3 FULL_RATE ranks=%u cs/dimm=%u dq/dqs=%u,%u vg/dqs=%u,%u ",
                   RW_MGR_MEM_NUMBER_OF_RANKS, RW_MGR_MEM_NUMBER_OF_CS_PER_DIMM,
                   RW_MGR_MEM_DQ_PER_READ_DQS, RW_MGR_MEM_DQ_PER_WRITE_DQS,
                   RW_MGR_MEM_VIRTUAL_GROUPS_PER_READ_DQS,
                   RW_MGR_MEM_VIRTUAL_GROUPS_PER_WRITE_DQS);
        debug_cond(DLEVEL == 1,
                   "dqs=%u,%u dq=%u dm=%u ptap_delay=%u dtap_delay=%u ",
                   RW_MGR_MEM_IF_READ_DQS_WIDTH, RW_MGR_MEM_IF_WRITE_DQS_WIDTH,
                   RW_MGR_MEM_DATA_WIDTH, RW_MGR_MEM_DATA_MASK_WIDTH,
                   IO_DELAY_PER_OPA_TAP, IO_DELAY_PER_DCHAIN_TAP);
        debug_cond(DLEVEL == 1, "dtap_dqsen_delay=%u, dll=%u",
                   IO_DELAY_PER_DQS_EN_DCHAIN_TAP, IO_DLL_CHAIN_LENGTH);
        debug_cond(DLEVEL == 1, "max values: en_p=%u dqdqs_p=%u en_d=%u dqs_in_d=%u ",
                   IO_DQS_EN_PHASE_MAX, IO_DQDQS_OUT_PHASE_MAX,
                   IO_DQS_EN_DELAY_MAX, IO_DQS_IN_DELAY_MAX);
        debug_cond(DLEVEL == 1, "io_in_d=%u io_out1_d=%u io_out2_d=%u ",
                   IO_IO_IN_DELAY_MAX, IO_IO_OUT1_DELAY_MAX,
                   IO_IO_OUT2_DELAY_MAX);
        debug_cond(DLEVEL == 1, "dqs_in_reserve=%u dqs_out_reserve=%u\n",
                   IO_DQS_IN_RESERVE, IO_DQS_OUT_RESERVE);

        hc_initialize_rom_data();

        /* update info for sims */
        reg_file_set_stage(CAL_STAGE_NIL);
        reg_file_set_group(0);

        /*
         * Load global needed for those actions that require
         * some dynamic calibration support.
         */
        dyn_calib_steps = STATIC_CALIB_STEPS;
        /*
         * Load global to allow dynamic selection of delay loop settings
         * based on calibration mode.
         */
        if (!(dyn_calib_steps & CALIB_SKIP_DELAY_LOOPS))
                skip_delay_mask = 0xff;
        else
                skip_delay_mask = 0x0;

        pass = run_mem_calibrate();

        printf("%s: Calibration complete\n", __FILE__);
        return pass;
}