board/prodrive/alpr/nand.c

   1 /*
   2  * (C) Copyright 2006
   3  * Heiko Schocher, DENX Software Engineering, hs@denx.de
   4  *
   5  * (C) Copyright 2006
   6  * Stefan Roese, DENX Software Engineering, sr@denx.de.
   7  *
   8  * SPDX-License-Identifier:     GPL-2.0+
   9  */
  10
  11 #include <common.h>
  12
  13 #if defined(CONFIG_CMD_NAND)
  14
  15 #include <asm/processor.h>
  16 #include <nand.h>
  17
  18 struct alpr_ndfc_regs {
  19         u8 cmd[4];
  20         u8 addr_wait;
  21         u8 term;
  22         u8 dummy;
  23         u8 dummy2;
  24         u8 data;
  25 };
  26
  27 static u8 hwctl;
  28 static struct alpr_ndfc_regs *alpr_ndfc = NULL;
  29
  30 #define readb(addr)     (u8)(*(volatile u8 *)(addr))
  31 #define writeb(d,addr)  *(volatile u8 *)(addr) = ((u8)(d))
  32
  33 /*
  34  * The ALPR has a NAND Flash Controller (NDFC) that handles all accesses to
  35  * the NAND devices.  The NDFC has command, address and data registers that
  36  * when accessed will set up the NAND flash pins appropriately.  We'll use the
  37  * hwcontrol function to save the configuration in a global variable.
  38  * We can then use this information in the read and write functions to
  39  * determine which NDFC register to access.
  40  *
  41  * There are 2 NAND devices on the board, a Hynix HY27US08561A (1 GByte).
  42  */
  43 static void alpr_nand_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  44 {
  45         struct nand_chip *this = mtd->priv;
  46
  47         if (ctrl & NAND_CTRL_CHANGE) {
  48                 if ( ctrl & NAND_CLE )
  49                         hwctl |= 0x1;
  50                 else
  51                         hwctl &= ~0x1;
  52                 if ( ctrl & NAND_ALE )
  53                         hwctl |= 0x2;
  54                 else
  55                         hwctl &= ~0x2;
  56                 if ( (ctrl & NAND_NCE) != NAND_NCE)
  57                         writeb(0x00, &(alpr_ndfc->term));
  58         }
  59         if (cmd != NAND_CMD_NONE)
  60                 writeb(cmd, this->IO_ADDR_W);
  61 }
  62
  63 static u_char alpr_nand_read_byte(struct mtd_info *mtd)
  64 {
  65         return readb(&(alpr_ndfc->data));
  66 }
  67
  68 static void alpr_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
  69 {
  70         struct nand_chip *nand = mtd->priv;
  71         int i;
  72
  73         for (i = 0; i < len; i++) {
  74                 if (hwctl & 0x1)
  75                          /*
  76                           * IO_ADDR_W used as CMD[i] reg to support multiple NAND
  77                           * chips.
  78                           */
  79                         writeb(buf[i], nand->IO_ADDR_W);
  80                 else if (hwctl & 0x2)
  81                         writeb(buf[i], &(alpr_ndfc->addr_wait));
  82                 else
  83                         writeb(buf[i], &(alpr_ndfc->data));
  84         }
  85 }
  86
  87 static void alpr_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
  88 {
  89         int i;
  90
  91         for (i = 0; i < len; i++) {
  92                 buf[i] = readb(&(alpr_ndfc->data));
  93         }
  94 }
  95
  96 #if defined(CONFIG_MTD_NAND_VERIFY_WRITE)
  97 static int alpr_nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
  98 {
  99         int i;
 100
 101         for (i = 0; i < len; i++)
 102                 if (buf[i] != readb(&(alpr_ndfc->data)))
 103                         return i;
 104
 105         return 0;
 106 }
 107 #endif
 108
 109 static int alpr_nand_dev_ready(struct mtd_info *mtd)
 110 {
 111         /*
 112          * Blocking read to wait for NAND to be ready
 113          */
 114         (void)readb(&(alpr_ndfc->addr_wait));
 115
 116         /*
 117          * Return always true
 118          */
 119         return 1;
 120 }
 121
 122 int board_nand_init(struct nand_chip *nand)
 123 {
 124         alpr_ndfc = (struct alpr_ndfc_regs *)CONFIG_SYS_NAND_BASE;
 125
 126         nand->ecc.mode = NAND_ECC_SOFT;
 127
 128         /* Reference hardware control function */
 129         nand->cmd_ctrl  = alpr_nand_hwcontrol;
 130         nand->read_byte  = alpr_nand_read_byte;
 131         nand->write_buf  = alpr_nand_write_buf;
 132         nand->read_buf   = alpr_nand_read_buf;
 133 #if defined(CONFIG_MTD_NAND_VERIFY_WRITE)
 134         nand->verify_buf = alpr_nand_verify_buf;
 135 #endif
 136         nand->dev_ready  = alpr_nand_dev_ready;
 137
 138         return 0;
 139 }
 140 #endif