board/synopsys/axs101/nand.c

   1 /*
   2  * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <bouncebuf.h>
   8 #include <common.h>
   9 #include <malloc.h>
  10 #include <nand.h>
  11 #include <asm/io.h>
  12
  13 #define BUS_WIDTH       8               /* AXI data bus width in bytes  */
  14
  15 /* DMA buffer descriptor bits & masks */
  16 #define BD_STAT_OWN                     (1 << 31)
  17 #define BD_STAT_BD_FIRST                (1 << 3)
  18 #define BD_STAT_BD_LAST                 (1 << 2)
  19 #define BD_SIZES_BUFFER1_MASK           0xfff
  20
  21 #define BD_STAT_BD_COMPLETE     (BD_STAT_BD_FIRST | BD_STAT_BD_LAST)
  22
  23 /* Controller command flags */
  24 #define B_WFR           (1 << 19)       /* 1b - Wait for ready          */
  25 #define B_LC            (1 << 18)       /* 1b - Last cycle              */
  26 #define B_IWC           (1 << 13)       /* 1b - Interrupt when complete */
  27
  28 /* NAND cycle types */
  29 #define B_CT_ADDRESS    (0x0 << 16)     /* Address operation            */
  30 #define B_CT_COMMAND    (0x1 << 16)     /* Command operation            */
  31 #define B_CT_WRITE      (0x2 << 16)     /* Write operation              */
  32 #define B_CT_READ       (0x3 << 16)     /* Write operation              */
  33
  34 enum nand_isr_t {
  35         NAND_ISR_DATAREQUIRED = 0,
  36         NAND_ISR_TXUNDERFLOW,
  37         NAND_ISR_TXOVERFLOW,
  38         NAND_ISR_DATAAVAILABLE,
  39         NAND_ISR_RXUNDERFLOW,
  40         NAND_ISR_RXOVERFLOW,
  41         NAND_ISR_TXDMACOMPLETE,
  42         NAND_ISR_RXDMACOMPLETE,
  43         NAND_ISR_DESCRIPTORUNAVAILABLE,
  44         NAND_ISR_CMDDONE,
  45         NAND_ISR_CMDAVAILABLE,
  46         NAND_ISR_CMDERROR,
  47         NAND_ISR_DATATRANSFEROVER,
  48         NAND_ISR_NONE
  49 };
  50
  51 enum nand_regs_t {
  52         AC_FIFO = 0,            /* address and command fifo */
  53         IDMAC_BDADDR = 0x18,    /* idmac descriptor list base address */
  54         INT_STATUS = 0x118,     /* interrupt status register */
  55         INT_CLR_STATUS = 0x120, /* interrupt clear status register */
  56 };
  57
  58 struct nand_bd {
  59         uint32_t status;        /* DES0 */
  60         uint32_t sizes;         /* DES1 */
  61         uint32_t buffer_ptr0;   /* DES2 */
  62         uint32_t buffer_ptr1;   /* DES3 */
  63 };
  64
  65 #define NAND_REG_WRITE(r, v)    writel(v, CONFIG_SYS_NAND_BASE + r)
  66 #define NAND_REG_READ(r)        readl(CONFIG_SYS_NAND_BASE + r)
  67
  68 static struct nand_bd *bd;      /* DMA buffer descriptors       */
  69
  70 /**
  71  * axs101_nand_write_buf -  write buffer to chip
  72  * @mtd:        MTD device structure
  73  * @buf:        data buffer
  74  * @len:        number of bytes to write
  75  */
  76 static uint32_t nand_flag_is_set(uint32_t flag)
  77 {
  78         uint32_t reg = NAND_REG_READ(INT_STATUS);
  79
  80         if (reg & (1 << NAND_ISR_CMDERROR))
  81                 return 0;
  82
  83         if (reg & (1 << flag)) {
  84                 NAND_REG_WRITE(INT_CLR_STATUS, 1 << flag);
  85                 return 1;
  86         }
  87
  88         return 0;
  89 }
  90
  91 /**
  92  * axs101_nand_write_buf -  write buffer to chip
  93  * @mtd:        MTD device structure
  94  * @buf:        data buffer
  95  * @len:        number of bytes to write
  96  */
  97 static void axs101_nand_write_buf(struct mtd_info *mtd, const u_char *buf,
  98                                    int len)
  99 {
 100         struct bounce_buffer bbstate;
 101
 102         bounce_buffer_start(&bbstate, (void *)buf, len, GEN_BB_READ);
 103
 104         /* Setup buffer descriptor */
 105         writel(BD_STAT_OWN | BD_STAT_BD_COMPLETE, &bd->status);
 106         writel(ALIGN(len, BUS_WIDTH) & BD_SIZES_BUFFER1_MASK, &bd->sizes);
 107         writel(bbstate.bounce_buffer, &bd->buffer_ptr0);
 108         writel(0, &bd->buffer_ptr1);
 109
 110         /* Issue "write" command */
 111         NAND_REG_WRITE(AC_FIFO, B_CT_WRITE | B_WFR | B_IWC | B_LC | (len-1));
 112
 113         /* Wait for NAND command and DMA to complete */
 114         while (!nand_flag_is_set(NAND_ISR_CMDDONE))
 115                 ;
 116         while (!nand_flag_is_set(NAND_ISR_TXDMACOMPLETE))
 117                 ;
 118
 119         bounce_buffer_stop(&bbstate);
 120 }
 121
 122 /**
 123  * axs101_nand_read_buf -  read chip data into buffer
 124  * @mtd:        MTD device structure
 125  * @buf:        buffer to store data
 126  * @len:        number of bytes to read
 127  */
 128 static void axs101_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
 129 {
 130         struct bounce_buffer bbstate;
 131
 132         bounce_buffer_start(&bbstate, buf, len, GEN_BB_WRITE);
 133
 134         /* Setup buffer descriptor */
 135         writel(BD_STAT_OWN | BD_STAT_BD_COMPLETE, &bd->status);
 136         writel(ALIGN(len, BUS_WIDTH) & BD_SIZES_BUFFER1_MASK, &bd->sizes);
 137         writel(bbstate.bounce_buffer, &bd->buffer_ptr0);
 138         writel(0, &bd->buffer_ptr1);
 139
 140         /* Issue "read" command */
 141         NAND_REG_WRITE(AC_FIFO, B_CT_READ | B_WFR | B_IWC | B_LC | (len - 1));
 142
 143         /* Wait for NAND command and DMA to complete */
 144         while (!nand_flag_is_set(NAND_ISR_CMDDONE))
 145                 ;
 146         while (!nand_flag_is_set(NAND_ISR_RXDMACOMPLETE))
 147                 ;
 148
 149         bounce_buffer_stop(&bbstate);
 150 }
 151
 152 /**
 153  * axs101_nand_read_byte -  read one byte from the chip
 154  * @mtd:        MTD device structure
 155  */
 156 static u_char axs101_nand_read_byte(struct mtd_info *mtd)
 157 {
 158         u8 byte;
 159
 160         axs101_nand_read_buf(mtd, (uchar *)&byte, sizeof(byte));
 161         return byte;
 162 }
 163
 164 /**
 165  * axs101_nand_read_word -  read one word from the chip
 166  * @mtd:        MTD device structure
 167  */
 168 static u16 axs101_nand_read_word(struct mtd_info *mtd)
 169 {
 170         u16 word;
 171
 172         axs101_nand_read_buf(mtd, (uchar *)&word, sizeof(word));
 173         return word;
 174 }
 175
 176 /**
 177  * axs101_nand_hwcontrol - NAND control functions wrapper.
 178  * @mtd:        MTD device structure
 179  * @cmd:        Command
 180  */
 181 static void axs101_nand_hwcontrol(struct mtd_info *mtdinfo, int cmd,
 182                                    unsigned int ctrl)
 183 {
 184         if (cmd == NAND_CMD_NONE)
 185                 return;
 186
 187         cmd = cmd & 0xff;
 188
 189         switch (ctrl & (NAND_ALE | NAND_CLE)) {
 190         /* Address */
 191         case NAND_ALE:
 192                 cmd |= B_CT_ADDRESS;
 193                 break;
 194
 195         /* Command */
 196         case NAND_CLE:
 197                 cmd |= B_CT_COMMAND | B_WFR;
 198
 199                 break;
 200
 201         default:
 202                 debug("%s: unknown ctrl %#x\n", __func__, ctrl);
 203         }
 204
 205         NAND_REG_WRITE(AC_FIFO, cmd | B_LC);
 206         while (!nand_flag_is_set(NAND_ISR_CMDDONE))
 207                 ;
 208 }
 209
 210 int board_nand_init(struct nand_chip *nand)
 211 {
 212         bd = (struct nand_bd *)memalign(ARCH_DMA_MINALIGN,
 213                                         sizeof(struct nand_bd));
 214
 215         /* Set buffer descriptor address in IDMAC */
 216         NAND_REG_WRITE(IDMAC_BDADDR, bd);
 217
 218         nand->ecc.mode = NAND_ECC_SOFT;
 219         nand->cmd_ctrl = axs101_nand_hwcontrol;
 220         nand->read_byte = axs101_nand_read_byte;
 221         nand->read_word = axs101_nand_read_word;
 222         nand->write_buf = axs101_nand_write_buf;
 223         nand->read_buf = axs101_nand_read_buf;
 224
 225         return 0;
 226 }