]> git.kernelconcepts.de Git - karo-tx-uboot.git/blobdiff - drivers/mtd/nand/omap_gpmc.c
mtd: nand: omap: add CONFIG_NAND_OMAP_ECCSCHEME for selection of ecc-scheme
[karo-tx-uboot.git] / drivers / mtd / nand / omap_gpmc.c
index cee394ece4b7699bc3932c367f436aeb2debc885..5e7e6b337544f3f7543baf7e8c1bcee9242a00e4 100644 (file)
@@ -2,40 +2,26 @@
  * (C) Copyright 2004-2008 Texas Instruments, <www.ti.com>
  * Rohit Choraria <rohitkc@ti.com>
  *
- * See file CREDITS for list of people who contributed to this
- * project.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
+ * SPDX-License-Identifier:    GPL-2.0+
  */
 
 #include <common.h>
 #include <asm/io.h>
 #include <asm/errno.h>
 #include <asm/arch/mem.h>
-#include <asm/arch/omap_gpmc.h>
+#include <asm/arch/cpu.h>
+#include <asm/omap_gpmc.h>
 #include <linux/mtd/nand_ecc.h>
+#include <linux/bch.h>
 #include <linux/compiler.h>
 #include <nand.h>
-#ifdef CONFIG_AM33XX
-#include <asm/arch/elm.h>
-#endif
+#include <asm/omap_elm.h>
+
+#define BADBLOCK_MARKER_LENGTH 2
+#define SECTOR_BYTES           512
 
 static uint8_t cs;
-static __maybe_unused struct nand_ecclayout hw_nand_oob =
-       GPMC_NAND_HW_ECC_LAYOUT;
+static __maybe_unused struct nand_ecclayout omap_ecclayout;
 
 /*
  * omap_nand_hwcontrol - Set the address pointers corretly for the
@@ -238,13 +224,14 @@ static void __maybe_unused omap_enable_hwecc(struct mtd_info *mtd, int32_t mode)
 }
 
 /*
- * BCH8 support (needs ELM and thus AM33xx-only)
+ * Generic BCH interface
  */
-#ifdef CONFIG_AM33XX
 struct nand_bch_priv {
        uint8_t mode;
        uint8_t type;
        uint8_t nibbles;
+       struct bch_control *control;
+       enum omap_ecc ecc_scheme;
 };
 
 /* bch types */
@@ -252,20 +239,143 @@ struct nand_bch_priv {
 #define ECC_BCH8       1
 #define ECC_BCH16      2
 
+/* GPMC ecc engine settings */
+#define BCH_WRAPMODE_1         1       /* BCH wrap mode 1 */
+#define BCH_WRAPMODE_6         6       /* BCH wrap mode 6 */
+
 /* BCH nibbles for diff bch levels */
 #define NAND_ECC_HW_BCH ((uint8_t)(NAND_ECC_HW_OOB_FIRST) + 1)
 #define ECC_BCH4_NIBBLES       13
 #define ECC_BCH8_NIBBLES       26
 #define ECC_BCH16_NIBBLES      52
 
-static struct nand_ecclayout hw_bch8_nand_oob = GPMC_NAND_HW_BCH8_ECC_LAYOUT;
-
-static struct nand_bch_priv bch_priv = {
+/*
+ * This can be a single instance cause all current users have only one NAND
+ * with nearly the same setup (BCH8, some with ELM and others with sw BCH
+ * library).
+ * When some users with other BCH strength will exists this have to change!
+ */
+static __maybe_unused struct nand_bch_priv bch_priv = {
        .mode = NAND_ECC_HW_BCH,
        .type = ECC_BCH8,
-       .nibbles = ECC_BCH8_NIBBLES
+       .nibbles = ECC_BCH8_NIBBLES,
+       .control = NULL
 };
 
+/*
+ * omap_hwecc_init_bch - Initialize the BCH Hardware ECC for NAND flash in
+ *                             GPMC controller
+ * @mtd:       MTD device structure
+ * @mode:      Read/Write mode
+ */
+__maybe_unused
+static void omap_hwecc_init_bch(struct nand_chip *chip, int32_t mode)
+{
+       uint32_t val;
+       uint32_t dev_width = (chip->options & NAND_BUSWIDTH_16) >> 1;
+       uint32_t unused_length = 0;
+       uint32_t wr_mode = BCH_WRAPMODE_6;
+       struct nand_bch_priv *bch = chip->priv;
+
+       /* Clear the ecc result registers, select ecc reg as 1 */
+       writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
+
+       if (bch->ecc_scheme == OMAP_ECC_BCH8_CODE_HW) {
+               wr_mode = BCH_WRAPMODE_1;
+
+       switch (bch->nibbles) {
+       case ECC_BCH4_NIBBLES:
+               unused_length = 3;
+               break;
+       case ECC_BCH8_NIBBLES:
+               unused_length = 2;
+               break;
+       case ECC_BCH16_NIBBLES:
+               unused_length = 0;
+               break;
+       }
+
+       /*
+        * This is ecc_size_config for ELM mode.
+        * Here we are using different settings for read and write access and
+        * also depending on BCH strength.
+        */
+       switch (mode) {
+       case NAND_ECC_WRITE:
+               /* write access only setup eccsize1 config */
+               val = ((unused_length + bch->nibbles) << 22);
+               break;
+
+       case NAND_ECC_READ:
+       default:
+               /*
+                * by default eccsize0 selected for ecc1resultsize
+                * eccsize0 config.
+                */
+               val  = (bch->nibbles << 12);
+               /* eccsize1 config */
+               val |= (unused_length << 22);
+               break;
+       }
+       } else {
+       /*
+        * This ecc_size_config setting is for BCH sw library.
+        *
+        * Note: we only support BCH8 currently with BCH sw library!
+        * Should be really easy to adobt to BCH4, however some omap3 have
+        * flaws with BCH4.
+        *
+        * Here we are using wrapping mode 6 both for reading and writing, with:
+        *  size0 = 0  (no additional protected byte in spare area)
+        *  size1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
+        */
+       val = (32 << 22) | (0 << 12);
+       }
+       /* ecc size configuration */
+       writel(val, &gpmc_cfg->ecc_size_config);
+
+       /*
+        * Configure the ecc engine in gpmc
+        * We assume 512 Byte sector pages for access to NAND.
+        */
+       val  = (1 << 16);               /* enable BCH mode */
+       val |= (bch->type << 12);       /* setup BCH type */
+       val |= (wr_mode << 8);          /* setup wrapping mode */
+       val |= (dev_width << 7);        /* setup device width (16 or 8 bit) */
+       val |= (cs << 1);               /* setup chip select to work on */
+       debug("set ECC_CONFIG=0x%08x\n", val);
+       writel(val, &gpmc_cfg->ecc_config);
+}
+
+/*
+ * omap_enable_ecc_bch - This function enables the bch h/w ecc functionality
+ * @mtd:       MTD device structure
+ * @mode:      Read/Write mode
+ */
+__maybe_unused
+static void omap_enable_ecc_bch(struct mtd_info *mtd, int32_t mode)
+{
+       struct nand_chip *chip = mtd->priv;
+
+       omap_hwecc_init_bch(chip, mode);
+       /* enable ecc */
+       writel((readl(&gpmc_cfg->ecc_config) | 0x1), &gpmc_cfg->ecc_config);
+}
+
+/*
+ * omap_ecc_disable - Disable H/W ECC calculation
+ *
+ * @mtd:       MTD device structure
+ */
+static void __maybe_unused omap_ecc_disable(struct mtd_info *mtd)
+{
+       writel((readl(&gpmc_cfg->ecc_config) & ~0x1), &gpmc_cfg->ecc_config);
+}
+
+/*
+ * BCH support using ELM module
+ */
+#ifdef CONFIG_NAND_OMAP_ELM
 /*
  * omap_read_bch8_result - Read BCH result for BCH8 level
  *
@@ -304,18 +414,6 @@ static void omap_read_bch8_result(struct mtd_info *mtd, uint8_t big_endian,
        }
 }
 
-/*
- * omap_ecc_disable - Disable H/W ECC calculation
- *
- * @mtd:       MTD device structure
- *
- */
-static void omap_ecc_disable(struct mtd_info *mtd)
-{
-       writel((readl(&gpmc_cfg->ecc_config) & ~0x1),
-               &gpmc_cfg->ecc_config);
-}
-
 /*
  * omap_rotate_ecc_bch - Rotate the syndrome bytes
  *
@@ -467,87 +565,18 @@ static int omap_correct_data_bch(struct mtd_info *mtd, uint8_t *dat,
 
        return 0;
 }
-/*
- * omap_hwecc_init_bch - Initialize the BCH Hardware ECC for NAND flash in
- *                             GPMC controller
- * @mtd:       MTD device structure
- * @mode:      Read/Write mode
- */
-static void omap_hwecc_init_bch(struct nand_chip *chip, int32_t mode)
-{
-       uint32_t val, dev_width = (chip->options & NAND_BUSWIDTH_16) >> 1;
-       uint32_t unused_length = 0;
-       struct nand_bch_priv *bch = chip->priv;
-
-       switch (bch->nibbles) {
-       case ECC_BCH4_NIBBLES:
-               unused_length = 3;
-               break;
-       case ECC_BCH8_NIBBLES:
-               unused_length = 2;
-               break;
-       case ECC_BCH16_NIBBLES:
-               unused_length = 0;
-               break;
-       }
-
-       /* Clear the ecc result registers, select ecc reg as 1 */
-       writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
-
-       switch (mode) {
-       case NAND_ECC_WRITE:
-               /* eccsize1 config */
-               val = ((unused_length + bch->nibbles) << 22);
-               break;
-
-       case NAND_ECC_READ:
-       default:
-               /* by default eccsize0 selected for ecc1resultsize */
-               /* eccsize0 config */
-               val  = (bch->nibbles << 12);
-               /* eccsize1 config */
-               val |= (unused_length << 22);
-               break;
-       }
-       /* ecc size configuration */
-       writel(val, &gpmc_cfg->ecc_size_config);
-       /* by default 512bytes sector page is selected */
-       /* set bch mode */
-       val  = (1 << 16);
-       /* bch4 / bch8 / bch16 */
-       val |= (bch->type << 12);
-       /* set wrap mode to 1 */
-       val |= (1 << 8);
-       val |= (dev_width << 7);
-       val |= (cs << 1);
-       writel(val, &gpmc_cfg->ecc_config);
-}
-
-/*
- * omap_enable_ecc_bch- This function enables the bch h/w ecc functionality
- * @mtd:        MTD device structure
- * @mode:       Read/Write mode
- *
- */
-static void omap_enable_ecc_bch(struct mtd_info *mtd, int32_t mode)
-{
-       struct nand_chip *chip = mtd->priv;
-
-       omap_hwecc_init_bch(chip, mode);
-       /* enable ecc */
-       writel((readl(&gpmc_cfg->ecc_config) | 0x1), &gpmc_cfg->ecc_config);
-}
 
 /**
  * omap_read_page_bch - hardware ecc based page read function
  * @mtd:       mtd info structure
  * @chip:      nand chip info structure
  * @buf:       buffer to store read data
+ * @oob_required: caller expects OOB data read to chip->oob_poi
  * @page:      page number to read
  *
  */
 static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
-                               uint8_t *buf, int page)
+                               uint8_t *buf, int oob_required, int page)
 {
        int i, eccsize = chip->ecc.size;
        int eccbytes = chip->ecc.bytes;
@@ -599,78 +628,320 @@ static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
        }
        return 0;
 }
-#endif /* CONFIG_AM33XX */
+#endif /* CONFIG_NAND_OMAP_ELM */
 
-#ifndef CONFIG_SPL_BUILD
 /*
- * omap_nand_switch_ecc - switch the ECC operation b/w h/w ecc and s/w ecc.
- * The default is to come up on s/w ecc
+ * OMAP3 BCH8 support (with BCH library)
+ */
+#ifdef CONFIG_BCH
+/*
+ *  omap_calculate_ecc_bch_sw - Read BCH ECC result
  *
- * @hardware - 1 -switch to h/w ecc, 0 - s/w ecc
+ *  @mtd:      MTD device structure
+ *  @dat:      The pointer to data on which ecc is computed (unused here)
+ *  @ecc:      The ECC output buffer
+ */
+static int omap_calculate_ecc_bch_sw(struct mtd_info *mtd, const uint8_t *dat,
+                               uint8_t *ecc)
+{
+       int ret = 0;
+       size_t i;
+       unsigned long nsectors, val1, val2, val3, val4;
+
+       nsectors = ((readl(&gpmc_cfg->ecc_config) >> 4) & 0x7) + 1;
+
+       for (i = 0; i < nsectors; i++) {
+               /* Read hw-computed remainder */
+               val1 = readl(&gpmc_cfg->bch_result_0_3[i].bch_result_x[0]);
+               val2 = readl(&gpmc_cfg->bch_result_0_3[i].bch_result_x[1]);
+               val3 = readl(&gpmc_cfg->bch_result_0_3[i].bch_result_x[2]);
+               val4 = readl(&gpmc_cfg->bch_result_0_3[i].bch_result_x[3]);
+
+               /*
+                * Add constant polynomial to remainder, in order to get an ecc
+                * sequence of 0xFFs for a buffer filled with 0xFFs.
+                */
+               *ecc++ = 0xef ^ (val4 & 0xFF);
+               *ecc++ = 0x51 ^ ((val3 >> 24) & 0xFF);
+               *ecc++ = 0x2e ^ ((val3 >> 16) & 0xFF);
+               *ecc++ = 0x09 ^ ((val3 >> 8) & 0xFF);
+               *ecc++ = 0xed ^ (val3 & 0xFF);
+               *ecc++ = 0x93 ^ ((val2 >> 24) & 0xFF);
+               *ecc++ = 0x9a ^ ((val2 >> 16) & 0xFF);
+               *ecc++ = 0xc2 ^ ((val2 >> 8) & 0xFF);
+               *ecc++ = 0x97 ^ (val2 & 0xFF);
+               *ecc++ = 0x79 ^ ((val1 >> 24) & 0xFF);
+               *ecc++ = 0xe5 ^ ((val1 >> 16) & 0xFF);
+               *ecc++ = 0x24 ^ ((val1 >> 8) & 0xFF);
+               *ecc++ = 0xb5 ^ (val1 & 0xFF);
+       }
+
+       /*
+        * Stop reading anymore ECC vals and clear old results
+        * enable will be called if more reads are required
+        */
+       omap_ecc_disable(mtd);
+
+       return ret;
+}
+
+/**
+ * omap_correct_data_bch_sw - Decode received data and correct errors
+ * @mtd: MTD device structure
+ * @data: page data
+ * @read_ecc: ecc read from nand flash
+ * @calc_ecc: ecc read from HW ECC registers
+ */
+static int omap_correct_data_bch_sw(struct mtd_info *mtd, u_char *data,
+                                u_char *read_ecc, u_char *calc_ecc)
+{
+       int i, count;
+       /* cannot correct more than 8 errors */
+       unsigned int errloc[8];
+       struct nand_chip *chip = mtd->priv;
+       struct nand_bch_priv *chip_priv = chip->priv;
+       struct bch_control *bch = chip_priv->control;
+
+       count = decode_bch(bch, NULL, 512, read_ecc, calc_ecc, NULL, errloc);
+       if (count > 0) {
+               /* correct errors */
+               for (i = 0; i < count; i++) {
+                       /* correct data only, not ecc bytes */
+                       if (errloc[i] < 8*512)
+                               data[errloc[i]/8] ^= 1 << (errloc[i] & 7);
+                       printf("corrected bitflip %u\n", errloc[i]);
+#ifdef DEBUG
+                       puts("read_ecc: ");
+                       /*
+                        * BCH8 have 13 bytes of ECC; BCH4 needs adoption
+                        * here!
+                        */
+                       for (i = 0; i < 13; i++)
+                               printf("%02x ", read_ecc[i]);
+                       puts("\n");
+                       puts("calc_ecc: ");
+                       for (i = 0; i < 13; i++)
+                               printf("%02x ", calc_ecc[i]);
+                       puts("\n");
+#endif
+               }
+       } else if (count < 0) {
+               puts("ecc unrecoverable error\n");
+       }
+       return count;
+}
+
+/**
+ * omap_free_bch - Release BCH ecc resources
+ * @mtd: MTD device structure
+ */
+static void __maybe_unused omap_free_bch(struct mtd_info *mtd)
+{
+       struct nand_chip *chip = mtd->priv;
+       struct nand_bch_priv *chip_priv = chip->priv;
+       struct bch_control *bch = NULL;
+
+       if (chip_priv)
+               bch = chip_priv->control;
+
+       if (bch) {
+               free_bch(bch);
+               chip_priv->control = NULL;
+       }
+}
+#endif /* CONFIG_BCH */
+
+/**
+ * omap_select_ecc_scheme - configures driver for particular ecc-scheme
+ * @nand: NAND chip device structure
+ * @ecc_scheme: ecc scheme to configure
+ * @pagesize: number of main-area bytes per page of NAND device
+ * @oobsize: number of OOB/spare bytes per page of NAND device
+ */
+static int omap_select_ecc_scheme(struct nand_chip *nand,
+       enum omap_ecc ecc_scheme, unsigned int pagesize, unsigned int oobsize) {
+       struct nand_bch_priv    *bch            = nand->priv;
+       struct nand_ecclayout   *ecclayout      = nand->ecc.layout;
+       int eccsteps = pagesize / SECTOR_BYTES;
+       int i;
+
+       switch (ecc_scheme) {
+       case OMAP_ECC_HAM1_CODE_SW:
+               debug("nand: selected OMAP_ECC_HAM1_CODE_SW\n");
+               /* For this ecc-scheme, ecc.bytes, ecc.layout, ... are
+                * initialized in nand_scan_tail(), so just set ecc.mode */
+               bch_priv.control        = NULL;
+               bch_priv.type           = 0;
+               nand->ecc.mode          = NAND_ECC_SOFT;
+               nand->ecc.layout        = NULL;
+               nand->ecc.size          = pagesize;
+               bch->ecc_scheme         = OMAP_ECC_HAM1_CODE_SW;
+               break;
+
+       case OMAP_ECC_HAM1_CODE_HW:
+               debug("nand: selected OMAP_ECC_HAM1_CODE_HW\n");
+               /* check ecc-scheme requirements before updating ecc info */
+               if ((3 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
+                       printf("nand: error: insufficient OOB: require=%d\n", (
+                               (3 * eccsteps) + BADBLOCK_MARKER_LENGTH));
+                       return -EINVAL;
+               }
+               bch_priv.control        = NULL;
+               bch_priv.type           = 0;
+               /* populate ecc specific fields */
+               nand->ecc.mode          = NAND_ECC_HW;
+               nand->ecc.strength      = 1;
+               nand->ecc.size          = SECTOR_BYTES;
+               nand->ecc.bytes         = 3;
+               nand->ecc.hwctl         = omap_enable_hwecc;
+               nand->ecc.correct       = omap_correct_data;
+               nand->ecc.calculate     = omap_calculate_ecc;
+               /* define ecc-layout */
+               ecclayout->eccbytes     = nand->ecc.bytes * eccsteps;
+               for (i = 0; i < ecclayout->eccbytes; i++)
+                       ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH;
+               ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
+               ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
+                                               BADBLOCK_MARKER_LENGTH;
+               bch->ecc_scheme         = OMAP_ECC_HAM1_CODE_HW;
+               break;
+
+       case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
+#ifdef CONFIG_BCH
+               debug("nand: selected OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n");
+               /* check ecc-scheme requirements before updating ecc info */
+               if ((13 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
+                       printf("nand: error: insufficient OOB: require=%d\n", (
+                               (13 * eccsteps) + BADBLOCK_MARKER_LENGTH));
+                       return -EINVAL;
+               }
+               /* check if BCH S/W library can be used for error detection */
+               bch_priv.control = init_bch(13, 8, 0x201b);
+               if (!bch_priv.control) {
+                       printf("nand: error: could not init_bch()\n");
+                       return -ENODEV;
+               }
+               bch_priv.type = ECC_BCH8;
+               /* populate ecc specific fields */
+               nand->ecc.mode          = NAND_ECC_HW;
+               nand->ecc.strength      = 8;
+               nand->ecc.size          = SECTOR_BYTES;
+               nand->ecc.bytes         = 13;
+               nand->ecc.hwctl         = omap_enable_ecc_bch;
+               nand->ecc.correct       = omap_correct_data_bch_sw;
+               nand->ecc.calculate     = omap_calculate_ecc_bch_sw;
+               /* define ecc-layout */
+               ecclayout->eccbytes     = nand->ecc.bytes * eccsteps;
+               ecclayout->eccpos[0]    = BADBLOCK_MARKER_LENGTH;
+               for (i = 1; i < ecclayout->eccbytes; i++) {
+                       if (i % nand->ecc.bytes)
+                               ecclayout->eccpos[i] =
+                                               ecclayout->eccpos[i - 1] + 1;
+                       else
+                               ecclayout->eccpos[i] =
+                                               ecclayout->eccpos[i - 1] + 2;
+               }
+               ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
+               ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
+                                               BADBLOCK_MARKER_LENGTH;
+               omap_hwecc_init_bch(nand, NAND_ECC_READ);
+               bch->ecc_scheme         = OMAP_ECC_BCH8_CODE_HW_DETECTION_SW;
+               break;
+#else
+               printf("nand: error: CONFIG_BCH required for ECC\n");
+               return -EINVAL;
+#endif
+
+       case OMAP_ECC_BCH8_CODE_HW:
+#ifdef CONFIG_NAND_OMAP_ELM
+               debug("nand: selected OMAP_ECC_BCH8_CODE_HW\n");
+               /* check ecc-scheme requirements before updating ecc info */
+               if ((14 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
+                       printf("nand: error: insufficient OOB: require=%d\n", (
+                               (14 * eccsteps) + BADBLOCK_MARKER_LENGTH));
+                       return -EINVAL;
+               }
+               /* intialize ELM for ECC error detection */
+               elm_init();
+               bch_priv.type           = ECC_BCH8;
+               /* populate ecc specific fields */
+               nand->ecc.mode          = NAND_ECC_HW;
+               nand->ecc.strength      = 8;
+               nand->ecc.size          = SECTOR_BYTES;
+               nand->ecc.bytes         = 14;
+               nand->ecc.hwctl         = omap_enable_ecc_bch;
+               nand->ecc.correct       = omap_correct_data_bch;
+               nand->ecc.calculate     = omap_calculate_ecc_bch;
+               nand->ecc.read_page     = omap_read_page_bch;
+               /* define ecc-layout */
+               ecclayout->eccbytes     = nand->ecc.bytes * eccsteps;
+               for (i = 0; i < ecclayout->eccbytes; i++)
+                       ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH;
+               ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
+               ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
+                                               BADBLOCK_MARKER_LENGTH;
+               bch->ecc_scheme         = OMAP_ECC_BCH8_CODE_HW;
+               break;
+#else
+               printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n");
+               return -EINVAL;
+#endif
+
+       default:
+               debug("nand: error: ecc scheme not enabled or supported\n");
+               return -EINVAL;
+       }
+       return 0;
+}
+
+#ifndef CONFIG_SPL_BUILD
+/*
+ * omap_nand_switch_ecc - switch the ECC operation between different engines
+ * (h/w and s/w) and different algorithms (hamming and BCHx)
  *
+ * @hardware           - true if one of the HW engines should be used
+ * @eccstrength                - the number of bits that could be corrected
+ *                       (1 - hamming, 4 - BCH4, 8 - BCH8, 16 - BCH16)
  */
-void omap_nand_switch_ecc(int32_t hardware)
+int __maybe_unused omap_nand_switch_ecc(uint32_t hardware, uint32_t eccstrength)
 {
        struct nand_chip *nand;
        struct mtd_info *mtd;
+       int err = 0;
 
        if (nand_curr_device < 0 ||
            nand_curr_device >= CONFIG_SYS_MAX_NAND_DEVICE ||
            !nand_info[nand_curr_device].name) {
-               printf("Error: Can't switch ecc, no devices available\n");
-               return;
+               printf("nand: error: no NAND devices found\n");
+               return -ENODEV;
        }
 
        mtd = &nand_info[nand_curr_device];
        nand = mtd->priv;
-
        nand->options |= NAND_OWN_BUFFERS;
-
-       /* Reset ecc interface */
-       nand->ecc.read_page = NULL;
-       nand->ecc.write_page = NULL;
-       nand->ecc.read_oob = NULL;
-       nand->ecc.write_oob = NULL;
-       nand->ecc.hwctl = NULL;
-       nand->ecc.correct = NULL;
-       nand->ecc.calculate = NULL;
-
        /* Setup the ecc configurations again */
-       if (hardware == 1) {
-               nand->ecc.mode = NAND_ECC_HW;
-               nand->ecc.layout = &hw_nand_oob;
-               nand->ecc.size = 512;
-               nand->ecc.bytes = 3;
-               nand->ecc.hwctl = omap_enable_hwecc;
-               nand->ecc.correct = omap_correct_data;
-               nand->ecc.calculate = omap_calculate_ecc;
-               omap_hwecc_init(nand);
-               printf("HW ECC selected\n");
-#ifdef CONFIG_AM33XX
-       } else if (hardware == 2) {
-               nand->ecc.mode = NAND_ECC_HW;
-               nand->ecc.layout = &hw_bch8_nand_oob;
-               nand->ecc.size = 512;
-               nand->ecc.bytes = 14;
-               nand->ecc.read_page = omap_read_page_bch;
-               nand->ecc.hwctl = omap_enable_ecc_bch;
-               nand->ecc.correct = omap_correct_data_bch;
-               nand->ecc.calculate = omap_calculate_ecc_bch;
-               omap_hwecc_init_bch(nand, NAND_ECC_READ);
-               printf("HW BCH8 selected\n");
-#endif
+       if (hardware) {
+               if (eccstrength == 1) {
+                       err = omap_select_ecc_scheme(nand,
+                                       OMAP_ECC_HAM1_CODE_HW,
+                                       mtd->writesize, mtd->oobsize);
+               } else if (eccstrength == 8) {
+                       err = omap_select_ecc_scheme(nand,
+                                       OMAP_ECC_BCH8_CODE_HW,
+                                       mtd->writesize, mtd->oobsize);
+               } else {
+                       printf("nand: error: unsupported ECC scheme\n");
+                       return -EINVAL;
+               }
        } else {
-               nand->ecc.mode = NAND_ECC_SOFT;
-               /* Use mtd default settings */
-               nand->ecc.layout = NULL;
-               nand->ecc.size = 0;
-               printf("SW ECC selected\n");
+               err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW,
+                                       mtd->writesize, mtd->oobsize);
        }
 
        /* Update NAND handling after ECC mode switch */
-       nand_scan_tail(mtd);
-
-       nand->options &= ~NAND_OWN_BUFFERS;
+       if (!err)
+               err = nand_scan_tail(mtd);
+       return err;
 }
 #endif /* CONFIG_SPL_BUILD */
 
@@ -693,7 +964,7 @@ int board_nand_init(struct nand_chip *nand)
 {
        int32_t gpmc_config = 0;
        cs = 0;
-
+       int err = 0;
        /*
         * xloader/Uboot's gpmc configuration would have configured GPMC for
         * nand type of memory. The following logic scans and latches on to the
@@ -710,7 +981,7 @@ int board_nand_init(struct nand_chip *nand)
                cs++;
        }
        if (cs >= GPMC_MAX_CS) {
-               printf("NAND: Unable to find NAND settings in "
+               printf("nand: error: Unable to find NAND settings in "
                        "GPMC Configuration - quitting\n");
                return -ENODEV;
        }
@@ -722,48 +993,27 @@ int board_nand_init(struct nand_chip *nand)
 
        nand->IO_ADDR_R = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat;
        nand->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd;
-
-       nand->cmd_ctrl = omap_nand_hwcontrol;
-       nand->options = NAND_NO_PADDING | NAND_CACHEPRG | NAND_NO_AUTOINCR;
+       nand->priv      = &bch_priv;
+       nand->cmd_ctrl  = omap_nand_hwcontrol;
+       nand->options   |= NAND_NO_PADDING | NAND_CACHEPRG;
        /* If we are 16 bit dev, our gpmc config tells us that */
        if ((readl(&gpmc_cfg->cs[cs].config1) & 0x3000) == 0x1000)
                nand->options |= NAND_BUSWIDTH_16;
 
        nand->chip_delay = 100;
+       nand->ecc.layout = &omap_ecclayout;
 
-#ifdef CONFIG_AM33XX
-       /* required in case of BCH */
-       elm_init();
-
-       /* BCH info that will be correct for SPL or overridden otherwise. */
-       nand->priv = &bch_priv;
-#endif
-
-       /* Default ECC mode */
-#ifdef CONFIG_AM33XX
-       nand->ecc.mode = NAND_ECC_HW;
-       nand->ecc.layout = &hw_bch8_nand_oob;
-       nand->ecc.size = CONFIG_SYS_NAND_ECCSIZE;
-       nand->ecc.bytes = CONFIG_SYS_NAND_ECCBYTES;
-       nand->ecc.hwctl = omap_enable_ecc_bch;
-       nand->ecc.correct = omap_correct_data_bch;
-       nand->ecc.calculate = omap_calculate_ecc_bch;
-       nand->ecc.read_page = omap_read_page_bch;
-       omap_hwecc_init_bch(nand, NAND_ECC_READ);
-#else
-#if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_NAND_SOFTECC)
-       nand->ecc.mode = NAND_ECC_SOFT;
+       /* select ECC scheme */
+#if defined(CONFIG_NAND_OMAP_ECCSCHEME)
+       err = omap_select_ecc_scheme(nand, CONFIG_NAND_OMAP_ECCSCHEME,
+                       CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE);
 #else
-       nand->ecc.mode = NAND_ECC_HW;
-       nand->ecc.layout = &hw_nand_oob;
-       nand->ecc.size = CONFIG_SYS_NAND_ECCSIZE;
-       nand->ecc.bytes = CONFIG_SYS_NAND_ECCBYTES;
-       nand->ecc.hwctl = omap_enable_hwecc;
-       nand->ecc.correct = omap_correct_data;
-       nand->ecc.calculate = omap_calculate_ecc;
-       omap_hwecc_init(nand);
-#endif
+       /* pagesize and oobsize are not required to configure sw ecc-scheme */
+       err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW,
+                       0, 0);
 #endif
+       if (err)
+               return err;
 
 #ifdef CONFIG_SPL_BUILD
        if (nand->options & NAND_BUSWIDTH_16)