board/prodrive/pdnb3/nand.c

   1 /*
   2  * (C) Copyright 2006
   3  * Stefan Roese, DENX Software Engineering, sr@denx.de.
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9
  10 #if defined(CONFIG_CMD_NAND)
  11
  12 #include <nand.h>
  13
  14 struct pdnb3_ndfc_regs {
  15         uchar cmd;
  16         uchar wait;
  17         uchar addr;
  18         uchar term;
  19         uchar data;
  20 };
  21
  22 static u8 hwctl;
  23 static struct pdnb3_ndfc_regs *pdnb3_ndfc;
  24
  25 #define readb(addr)     *(volatile u_char *)(addr)
  26 #define readl(addr)     *(volatile u_long *)(addr)
  27 #define writeb(d,addr)  *(volatile u_char *)(addr) = (d)
  28
  29 /*
  30  * The PDNB3 has a NAND Flash Controller (NDFC) that handles all accesses to
  31  * the NAND devices.  The NDFC has command, address and data registers that
  32  * when accessed will set up the NAND flash pins appropriately.  We'll use the
  33  * hwcontrol function to save the configuration in a global variable.
  34  * We can then use this information in the read and write functions to
  35  * determine which NDFC register to access.
  36  *
  37  * There is one NAND devices on the board, a Hynix HY27US08561A (32 MByte).
  38  */
  39 static void pdnb3_nand_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  40 {
  41         struct nand_chip *this = mtd->priv;
  42
  43         if (ctrl & NAND_CTRL_CHANGE) {
  44                 if ( ctrl & NAND_CLE )
  45                         hwctl |= 0x1;
  46                 else
  47                         hwctl &= ~0x1;
  48                 if ( ctrl & NAND_ALE )
  49                         hwctl |= 0x2;
  50                 else
  51                         hwctl &= ~0x2;
  52                 if ( (ctrl & NAND_NCE) != NAND_NCE)
  53                         writeb(0x00, &(pdnb3_ndfc->term));
  54         }
  55         if (cmd != NAND_CMD_NONE)
  56                 writeb(cmd, this->IO_ADDR_W);
  57 }
  58
  59
  60 static u_char pdnb3_nand_read_byte(struct mtd_info *mtd)
  61 {
  62         return readb(&(pdnb3_ndfc->data));
  63 }
  64
  65 static void pdnb3_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
  66 {
  67         int i;
  68
  69         for (i = 0; i < len; i++) {
  70                 if (hwctl & 0x1)
  71                         writeb(buf[i], &(pdnb3_ndfc->cmd));
  72                 else if (hwctl & 0x2)
  73                         writeb(buf[i], &(pdnb3_ndfc->addr));
  74                 else
  75                         writeb(buf[i], &(pdnb3_ndfc->data));
  76         }
  77 }
  78
  79 static void pdnb3_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
  80 {
  81         int i;
  82
  83         for (i = 0; i < len; i++)
  84                 buf[i] = readb(&(pdnb3_ndfc->data));
  85 }
  86
  87 static int pdnb3_nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
  88 {
  89         int i;
  90
  91         for (i = 0; i < len; i++)
  92                 if (buf[i] != readb(&(pdnb3_ndfc->data)))
  93                         return i;
  94
  95         return 0;
  96 }
  97
  98 static int pdnb3_nand_dev_ready(struct mtd_info *mtd)
  99 {
 100         /*
 101          * Blocking read to wait for NAND to be ready
 102          */
 103         readb(&(pdnb3_ndfc->wait));
 104
 105         /*
 106          * Return always true
 107          */
 108         return 1;
 109 }
 110
 111 int board_nand_init(struct nand_chip *nand)
 112 {
 113         pdnb3_ndfc = (struct pdnb3_ndfc_regs *)CONFIG_SYS_NAND_BASE;
 114
 115         nand->ecc.mode = NAND_ECC_SOFT;
 116
 117         /* Set address of NAND IO lines (Using Linear Data Access Region) */
 118         nand->IO_ADDR_R = (void __iomem *) ((ulong) pdnb3_ndfc + 0x4);
 119         nand->IO_ADDR_W = (void __iomem *) ((ulong) pdnb3_ndfc + 0x4);
 120         /* Reference hardware control function */
 121         nand->cmd_ctrl   = pdnb3_nand_hwcontrol;
 122         nand->read_byte  = pdnb3_nand_read_byte;
 123         nand->write_buf  = pdnb3_nand_write_buf;
 124         nand->read_buf   = pdnb3_nand_read_buf;
 125         nand->verify_buf = pdnb3_nand_verify_buf;
 126         nand->dev_ready  = pdnb3_nand_dev_ready;
 127         return 0;
 128 }
 129 #endif