drivers/mtd/nand/kmeter1_nand.c

   1 /*
   2  * (C) Copyright 2009
   3  * Heiko Schocher, DENX Software Engineering, hs@denx.de
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <nand.h>
  10 #include <asm/io.h>
  11
  12 #define CONFIG_NAND_MODE_REG    (void *)(CONFIG_SYS_NAND_BASE + 0x20000)
  13 #define CONFIG_NAND_DATA_REG    (void *)(CONFIG_SYS_NAND_BASE + 0x30000)
  14
  15 #define read_mode()     in_8(CONFIG_NAND_MODE_REG)
  16 #define write_mode(val) out_8(CONFIG_NAND_MODE_REG, val)
  17 #define read_data()     in_8(CONFIG_NAND_DATA_REG)
  18 #define write_data(val) out_8(CONFIG_NAND_DATA_REG, val)
  19
  20 #define KPN_RDY2        (1 << 7)
  21 #define KPN_RDY1        (1 << 6)
  22 #define KPN_WPN         (1 << 4)
  23 #define KPN_CE2N        (1 << 3)
  24 #define KPN_CE1N        (1 << 2)
  25 #define KPN_ALE         (1 << 1)
  26 #define KPN_CLE         (1 << 0)
  27
  28 #define KPN_DEFAULT_CHIP_DELAY 50
  29
  30 static int kpn_chip_ready(void)
  31 {
  32         if (read_mode() & KPN_RDY1)
  33                 return 1;
  34
  35         return 0;
  36 }
  37
  38 static void kpn_wait_rdy(void)
  39 {
  40         int cnt = 1000000;
  41
  42         while (--cnt && !kpn_chip_ready())
  43                 udelay(1);
  44
  45         if (!cnt)
  46                 printf ("timeout while waiting for RDY\n");
  47 }
  48
  49 static void kpn_nand_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  50 {
  51         u8 reg_val = read_mode();
  52
  53         if (ctrl & NAND_CTRL_CHANGE) {
  54                 reg_val = reg_val & ~(KPN_ALE + KPN_CLE);
  55
  56                 if (ctrl & NAND_CLE)
  57                         reg_val = reg_val | KPN_CLE;
  58                 if (ctrl & NAND_ALE)
  59                         reg_val = reg_val | KPN_ALE;
  60                 if (ctrl & NAND_NCE)
  61                         reg_val = reg_val & ~KPN_CE1N;
  62                 else
  63                         reg_val = reg_val | KPN_CE1N;
  64
  65                 write_mode(reg_val);
  66         }
  67         if (cmd != NAND_CMD_NONE)
  68                 write_data(cmd);
  69
  70         /* wait until flash is ready */
  71         kpn_wait_rdy();
  72 }
  73
  74 static u_char kpn_nand_read_byte(struct mtd_info *mtd)
  75 {
  76         return read_data();
  77 }
  78
  79 static void kpn_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
  80 {
  81         int i;
  82
  83         for (i = 0; i < len; i++) {
  84                 write_data(buf[i]);
  85                 kpn_wait_rdy();
  86         }
  87 }
  88
  89 static void kpn_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
  90 {
  91         int i;
  92
  93         for (i = 0; i < len; i++)
  94                 buf[i] = read_data();
  95 }
  96
  97 static int kpn_nand_dev_ready(struct mtd_info *mtd)
  98 {
  99         kpn_wait_rdy();
 100
 101         return 1;
 102 }
 103
 104 int board_nand_init(struct nand_chip *nand)
 105 {
 106 #if defined(CONFIG_NAND_ECC_BCH)
 107         nand->ecc.mode = NAND_ECC_SOFT_BCH;
 108 #else
 109         nand->ecc.mode = NAND_ECC_SOFT;
 110 #endif
 111
 112         /* Reference hardware control function */
 113         nand->cmd_ctrl  = kpn_nand_hwcontrol;
 114         nand->read_byte  = kpn_nand_read_byte;
 115         nand->write_buf  = kpn_nand_write_buf;
 116         nand->read_buf   = kpn_nand_read_buf;
 117         nand->dev_ready  = kpn_nand_dev_ready;
 118         nand->chip_delay = KPN_DEFAULT_CHIP_DELAY;
 119
 120         /* reset mode register */
 121         write_mode(KPN_CE1N + KPN_CE2N + KPN_WPN);
 122         return 0;
 123 }