cpu/arm920t/s3c24x0/nand_read.c

   1 /*
   2  * nand_read.c: Simple NAND read functions for booting from NAND
   3  *
   4  * This is used by cpu/arm920/start.S assembler code,
   5  * and the board-specific linker script must make sure this
   6  * file is linked within the first 4kB of NAND flash.
   7  *
   8  * Taken from GPLv2 licensed vivi bootloader,
   9  * Copyright (C) 2002 MIZI Research, Inc.
  10  *
  11  * Author: Hwang, Chideok <hwang@mizi.com>
  12  * Date  : $Date: 2004/02/04 10:37:37 $
  13  *
  14  * u-boot integration and bad-block skipping (C) 2006 by OpenMoko, Inc.
  15  * Author: Harald Welte <laforge@openmoko.org>
  16  */
  17
  18 #include <common.h>
  19 #include <linux/mtd/nand.h>
  20
  21 #ifdef CONFIG_S3C2410_NAND_BOOT
  22
  23 #define __REGb(x)       (*(volatile unsigned char *)(x))
  24 #define __REGw(x)       (*(volatile unsigned short *)(x))
  25 #define __REGi(x)       (*(volatile unsigned int *)(x))
  26 #define NF_BASE         0x4e000000
  27 #if defined(CONFIG_S3C2410)
  28 #define NFCONF          __REGi(NF_BASE + 0x0)
  29 #define NFCMD           __REGb(NF_BASE + 0x4)
  30 #define NFADDR          __REGb(NF_BASE + 0x8)
  31 #define NFDATA          __REGb(NF_BASE + 0xc)
  32 #define NFSTAT          __REGb(NF_BASE + 0x10)
  33 #define NFSTAT_BUSY     1
  34 #define nand_select()   (NFCONF &= ~0x800)
  35 #define nand_deselect() (NFCONF |= 0x800)
  36 #define nand_clear_RnB()        do {} while (0)
  37 #elif defined(CONFIG_S3C2440) || defined(CONFIG_S3C2442)
  38 #define NFCONF          __REGi(NF_BASE + 0x0)
  39 #define NFCONT          __REGi(NF_BASE + 0x4)
  40 #define NFCMD           __REGb(NF_BASE + 0x8)
  41 #define NFADDR          __REGb(NF_BASE + 0xc)
  42 #define NFDATA          __REGb(NF_BASE + 0x10)
  43 #define NFDATA16        __REGw(NF_BASE + 0x10)
  44 #define NFSTAT          __REGb(NF_BASE + 0x20)
  45 #define NFSTAT_BUSY     1
  46 #define nand_select()   (NFCONT &= ~(1 << 1))
  47 #define nand_deselect() (NFCONT |= (1 << 1))
  48 #define nand_clear_RnB()        (NFSTAT |= (1 << 2))
  49 #endif
  50
  51 static inline void nand_wait(void)
  52 {
  53         int i;
  54
  55         while (!(NFSTAT & NFSTAT_BUSY))
  56                 for (i=0; i<10; i++);
  57 }
  58
  59 struct boot_nand_t {
  60         int page_size;
  61         int block_size;
  62         int bad_block_offset;
  63         unsigned long size;
  64 };
  65
  66 #if 0
  67 #if defined(CONFIG_S3C2410) || defined(CONFIG_MINI2440)
  68 /* configuration for 2410 with 512byte sized flash */
  69 #define NAND_PAGE_SIZE          512
  70 #define BAD_BLOCK_OFFSET        5
  71 #define NAND_BLOCK_MASK         (NAND_PAGE_SIZE - 1)
  72 #define NAND_BLOCK_SIZE         0x4000
  73 #else
  74 /* configuration for 2440 with 2048byte sized flash */
  75 #define NAND_5_ADDR_CYCLE
  76 #define NAND_PAGE_SIZE          2048
  77 #define BAD_BLOCK_OFFSET        NAND_PAGE_SIZE
  78 #define NAND_BLOCK_MASK         (NAND_PAGE_SIZE - 1)
  79 #define NAND_BLOCK_SIZE         (NAND_PAGE_SIZE * 64)
  80 #endif
  81
  82 /* compile time failure in case of an invalid configuration */
  83 #if defined(CONFIG_S3C2410) && (NAND_PAGE_SIZE != 512)
  84 #error "S3C2410 does not support nand page size != 512"
  85 #endif
  86 #endif
  87
  88 static int is_bad_block(struct boot_nand_t * nand, unsigned long i)
  89 {
  90         unsigned char data;
  91         unsigned long page_num;
  92
  93         nand_clear_RnB();
  94         if (nand->page_size == 512) {
  95                 NFCMD = NAND_CMD_READOOB; /* 0x50 */
  96                 NFADDR = nand->bad_block_offset & 0xf;
  97                 NFADDR = (i >> 9) & 0xff;
  98                 NFADDR = (i >> 17) & 0xff;
  99                 NFADDR = (i >> 25) & 0xff;
 100         } else if (nand->page_size == 2048) {
 101                 page_num = i >> 11; /* addr / 2048 */
 102                 NFCMD = NAND_CMD_READ0;
 103                 NFADDR = nand->bad_block_offset & 0xff;
 104                 NFADDR = (nand->bad_block_offset >> 8) & 0xff;
 105                 NFADDR = page_num & 0xff;
 106                 NFADDR = (page_num >> 8) & 0xff;
 107                 NFADDR = (page_num >> 16) & 0xff;
 108                 NFCMD = NAND_CMD_READSTART;
 109         } else {
 110                 return -1;
 111         }
 112         nand_wait();
 113         data = (NFDATA & 0xff);
 114         if (data != 0xff)
 115                 return 1;
 116
 117         return 0;
 118 }
 119
 120 static int nand_read_page_ll(struct boot_nand_t * nand, unsigned char *buf, unsigned long addr)
 121 {
 122         unsigned short *ptr16 = (unsigned short *)buf;
 123         unsigned int i, page_num;
 124
 125         nand_clear_RnB();
 126
 127         NFCMD = NAND_CMD_READ0;
 128
 129         if (nand->page_size == 512) {
 130                 /* Write Address */
 131                 NFADDR = addr & 0xff;
 132                 NFADDR = (addr >> 9) & 0xff;
 133                 NFADDR = (addr >> 17) & 0xff;
 134                 NFADDR = (addr >> 25) & 0xff;
 135         } else if (nand->page_size == 2048) {
 136                 page_num = addr >> 11; /* addr / 2048 */
 137                 /* Write Address */
 138                 NFADDR = 0;
 139                 NFADDR = 0;
 140                 NFADDR = page_num & 0xff;
 141                 NFADDR = (page_num >> 8) & 0xff;
 142                 NFADDR = (page_num >> 16) & 0xff;
 143                 NFCMD = NAND_CMD_READSTART;
 144         } else {
 145                 return -1;
 146         }
 147         nand_wait();
 148
 149 #if defined(CONFIG_S3C2410)
 150         for (i = 0; i < nand->page_size; i++) {
 151                 *buf = (NFDATA & 0xff);
 152                 buf++;
 153         }
 154 #elif defined(CONFIG_S3C2440) || defined(CONFIG_S3C2442)
 155         for (i = 0; i < (nand->page_size>>1); i++) {
 156                 *ptr16 = NFDATA16;
 157                 ptr16++;
 158         }
 159 #endif
 160
 161         return nand->page_size;
 162 }
 163
 164 static unsigned short nand_read_id()
 165 {
 166         unsigned short res = 0;
 167         NFCMD = NAND_CMD_READID;
 168         NFADDR = 0;
 169         res = NFDATA;
 170         res = (res << 8) | NFDATA;
 171         return res;
 172 }
 173
 174 extern unsigned int dynpart_size[];
 175
 176 /* low level nand read function */
 177 int nand_read_ll(unsigned char *buf, unsigned long start_addr, int size)
 178 {
 179         int i, j;
 180         unsigned short nand_id;
 181         struct boot_nand_t nand;
 182
 183         /* chip Enable */
 184         nand_select();
 185         nand_clear_RnB();
 186
 187         for (i = 0; i < 10; i++)
 188                 ;
 189         nand_id = nand_read_id();
 190         if (0) { /* dirty little hack to detect if nand id is misread */
 191                 unsigned short * nid = (unsigned short *)0x31fffff0;
 192                 *nid = nand_id;
 193         }
 194
 195         if (nand_id == 0xec76) {        /* Samsung K91208 */
 196                 nand.page_size = 512;
 197                 nand.block_size = 16 * 1024;
 198                 nand.bad_block_offset = 5;
 199                 nand.size = 0x4000000;
 200         } else if (nand_id == 0xecf1) { /* Samsung K9F1G08U0B */
 201                 nand.page_size = 2048;
 202                 nand.block_size = 128 * 1024;
 203                 nand.bad_block_offset = nand.page_size;
 204                 nand.size = 0x8000000;
 205         } else {
 206                 return -1; // hang
 207         }
 208         if ((start_addr & (nand.block_size-1)) || (size & ((nand.block_size-1))))
 209                 return -1;      /* invalid alignment */
 210
 211         for (i=start_addr; i < (start_addr + size);) {
 212 #ifdef CONFIG_S3C2410_NAND_SKIP_BAD
 213                 if (i & (nand.block_size-1)== 0) {
 214                         if (is_bad_block(&nand, i) ||
 215                             is_bad_block(&nand, i + nand.page_size)) {
 216                                 /* Bad block */
 217                                 i += nand.block_size;
 218                                 size += nand.block_size;
 219                                 continue;
 220                         }
 221                 }
 222 #endif
 223                 j = nand_read_page_ll(&nand, buf, i);
 224                 i += j;
 225                 buf += j;
 226         }
 227
 228         /* chip Disable */
 229         nand_deselect();
 230
 231         return 0;
 232 }
 233
 234 #endif /* CONFIG_S3C2410_NAND_BOOT */