nand_spl/nand_boot.c

   1 /*
   2  * (C) Copyright 2006-2008
   3  * Stefan Roese, DENX Software Engineering, sr@denx.de.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation; either version 2 of
   8  * the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  18  * MA 02111-1307 USA
  19  */
  20
  21 #include <common.h>
  22 #include <nand.h>
  23 #include <asm/io.h>
  24
  25 #define CONFIG_SYS_NAND_READ_DELAY \
  26         { volatile int dummy; int i; for (i=0; i<10000; i++) dummy = i; }
  27
  28 static int nand_ecc_pos[] = CONFIG_SYS_NAND_ECCPOS;
  29
  30 #if (CONFIG_SYS_NAND_PAGE_SIZE <= 512)
  31 /*
  32  * NAND command for small page NAND devices (512)
  33  */
  34 static int nand_command(struct mtd_info *mtd, int block, int page, int offs, u8 cmd)
  35 {
  36         struct nand_chip *this = mtd->priv;
  37         int page_addr = page + block * CONFIG_SYS_NAND_PAGE_COUNT;
  38
  39         if (this->dev_ready)
  40                 while (!this->dev_ready(mtd))
  41                         ;
  42         else
  43                 CONFIG_SYS_NAND_READ_DELAY;
  44
  45         /* Begin command latch cycle */
  46         this->cmd_ctrl(mtd, cmd, NAND_CTRL_CLE | NAND_CTRL_CHANGE);
  47         /* Set ALE and clear CLE to start address cycle */
  48         /* Column address */
  49         this->cmd_ctrl(mtd, offs, NAND_CTRL_ALE | NAND_CTRL_CHANGE);
  50         this->cmd_ctrl(mtd, page_addr & 0xff, NAND_CTRL_ALE); /* A[16:9] */
  51         this->cmd_ctrl(mtd, (page_addr >> 8) & 0xff,
  52                        NAND_CTRL_ALE); /* A[24:17] */
  53 #ifdef CONFIG_SYS_NAND_4_ADDR_CYCLE
  54         /* One more address cycle for devices > 32MiB */
  55         this->cmd_ctrl(mtd, (page_addr >> 16) & 0x0f,
  56                        NAND_CTRL_ALE); /* A[28:25] */
  57 #endif
  58         /* Latch in address */
  59         this->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
  60
  61         /*
  62          * Wait a while for the data to be ready
  63          */
  64         if (this->dev_ready)
  65                 while (!this->dev_ready(mtd))
  66                         ;
  67         else
  68                 CONFIG_SYS_NAND_READ_DELAY;
  69
  70         return 0;
  71 }
  72 #else
  73 /*
  74  * NAND command for large page NAND devices (2k)
  75  */
  76 static int nand_command(struct mtd_info *mtd, int block, int page, int offs, u8 cmd)
  77 {
  78         struct nand_chip *this = mtd->priv;
  79         int page_addr = page + block * CONFIG_SYS_NAND_PAGE_COUNT;
  80
  81         if (this->dev_ready)
  82                 while (!this->dev_ready(mtd))
  83                         ;
  84         else
  85                 CONFIG_SYS_NAND_READ_DELAY;
  86
  87         /* Emulate NAND_CMD_READOOB */
  88         if (cmd == NAND_CMD_READOOB) {
  89                 offs += CONFIG_SYS_NAND_PAGE_SIZE;
  90                 cmd = NAND_CMD_READ0;
  91         }
  92
  93         /* Begin command latch cycle */
  94         this->cmd_ctrl(mtd, cmd, NAND_CTRL_CLE | NAND_CTRL_CHANGE);
  95         /* Set ALE and clear CLE to start address cycle */
  96         /* Column address */
  97         this->cmd_ctrl(mtd, offs & 0xff,
  98                        NAND_CTRL_ALE | NAND_CTRL_CHANGE); /* A[7:0] */
  99         this->cmd_ctrl(mtd, (offs >> 8) & 0xff, NAND_CTRL_ALE); /* A[11:9] */
 100         /* Row address */
 101         this->cmd_ctrl(mtd, (page_addr & 0xff), NAND_CTRL_ALE); /* A[19:12] */
 102         this->cmd_ctrl(mtd, ((page_addr >> 8) & 0xff),
 103                        NAND_CTRL_ALE); /* A[27:20] */
 104 #ifdef CONFIG_SYS_NAND_5_ADDR_CYCLE
 105         /* One more address cycle for devices > 128MiB */
 106         this->cmd_ctrl(mtd, (page_addr >> 16) & 0x0f,
 107                        NAND_CTRL_ALE); /* A[31:28] */
 108 #endif
 109         /* Latch in address */
 110         this->cmd_ctrl(mtd, NAND_CMD_READSTART,
 111                        NAND_CTRL_CLE | NAND_CTRL_CHANGE);
 112         this->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 113
 114         /*
 115          * Wait a while for the data to be ready
 116          */
 117         if (this->dev_ready)
 118                 while (!this->dev_ready(mtd))
 119                         ;
 120         else
 121                 CONFIG_SYS_NAND_READ_DELAY;
 122
 123         return 0;
 124 }
 125 #endif
 126
 127 static int nand_is_bad_block(struct mtd_info *mtd, int block)
 128 {
 129         struct nand_chip *this = mtd->priv;
 130
 131         nand_command(mtd, block, 0, CONFIG_SYS_NAND_BAD_BLOCK_POS, NAND_CMD_READOOB);
 132
 133         /*
 134          * Read one byte
 135          */
 136         if (readb(this->IO_ADDR_R) != 0xff)
 137                 return 1;
 138
 139         return 0;
 140 }
 141
 142 static int nand_read_page(struct mtd_info *mtd, int block, int page, uchar *dst)
 143 {
 144         struct nand_chip *this = mtd->priv;
 145         u_char *ecc_calc;
 146         u_char *ecc_code;
 147         u_char *oob_data;
 148         int i;
 149         int eccsize = CONFIG_SYS_NAND_ECCSIZE;
 150         int eccbytes = CONFIG_SYS_NAND_ECCBYTES;
 151         int eccsteps = CONFIG_SYS_NAND_ECCSTEPS;
 152         uint8_t *p = dst;
 153         int stat;
 154
 155         nand_command(mtd, block, page, 0, NAND_CMD_READ0);
 156
 157         /* No malloc available for now, just use some temporary locations
 158          * in SDRAM
 159          */
 160         ecc_calc = (u_char *)(CONFIG_SYS_SDRAM_BASE + 0x10000);
 161         ecc_code = ecc_calc + 0x100;
 162         oob_data = ecc_calc + 0x200;
 163
 164         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 165                 this->ecc.hwctl(mtd, NAND_ECC_READ);
 166                 this->read_buf(mtd, p, eccsize);
 167                 this->ecc.calculate(mtd, p, &ecc_calc[i]);
 168         }
 169         this->read_buf(mtd, oob_data, CONFIG_SYS_NAND_OOBSIZE);
 170
 171         /* Pick the ECC bytes out of the oob data */
 172         for (i = 0; i < CONFIG_SYS_NAND_ECCTOTAL; i++)
 173                 ecc_code[i] = oob_data[nand_ecc_pos[i]];
 174
 175         eccsteps = CONFIG_SYS_NAND_ECCSTEPS;
 176         p = dst;
 177
 178         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 179                 /* No chance to do something with the possible error message
 180                  * from correct_data(). We just hope that all possible errors
 181                  * are corrected by this routine.
 182                  */
 183                 stat = this->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
 184         }
 185
 186         return 0;
 187 }
 188
 189 static int nand_load(struct mtd_info *mtd, unsigned int offs,
 190                      unsigned int uboot_size, uchar *dst)
 191 {
 192         unsigned int block, lastblock;
 193         unsigned int page;
 194
 195         /*
 196          * offs has to be aligned to a page address!
 197          */
 198         block = offs / CONFIG_SYS_NAND_BLOCK_SIZE;
 199         lastblock = (offs + uboot_size - 1) / CONFIG_SYS_NAND_BLOCK_SIZE;
 200         page = (offs % CONFIG_SYS_NAND_BLOCK_SIZE) / CONFIG_SYS_NAND_PAGE_SIZE;
 201
 202         while (block <= lastblock) {
 203                 if (!nand_is_bad_block(mtd, block)) {
 204                         /*
 205                          * Skip bad blocks
 206                          */
 207                         while (page < CONFIG_SYS_NAND_PAGE_COUNT) {
 208                                 nand_read_page(mtd, block, page, dst);
 209                                 dst += CONFIG_SYS_NAND_PAGE_SIZE;
 210                                 page++;
 211                         }
 212
 213                         page = 0;
 214                 } else {
 215                         lastblock++;
 216                 }
 217
 218                 block++;
 219         }
 220
 221         return 0;
 222 }
 223
 224 /*
 225  * The main entry for NAND booting. It's necessary that SDRAM is already
 226  * configured and available since this code loads the main U-Boot image
 227  * from NAND into SDRAM and starts it from there.
 228  */
 229 void nand_boot(void)
 230 {
 231         struct nand_chip nand_chip;
 232         nand_info_t nand_info;
 233         int ret;
 234         __attribute__((noreturn)) void (*uboot)(void);
 235
 236         /*
 237          * Init board specific nand support
 238          */
 239         nand_info.priv = &nand_chip;
 240         nand_chip.IO_ADDR_R = nand_chip.IO_ADDR_W = (void  __iomem *)CONFIG_SYS_NAND_BASE;
 241         nand_chip.dev_ready = NULL;     /* preset to NULL */
 242         board_nand_init(&nand_chip);
 243
 244         if (nand_chip.select_chip)
 245                 nand_chip.select_chip(&nand_info, 0);
 246
 247         /*
 248          * Load U-Boot image from NAND into RAM
 249          */
 250         ret = nand_load(&nand_info, CONFIG_SYS_NAND_U_BOOT_OFFS, CONFIG_SYS_NAND_U_BOOT_SIZE,
 251                         (uchar *)CONFIG_SYS_NAND_U_BOOT_DST);
 252
 253 #ifdef CONFIG_NAND_ENV_DST
 254         nand_load(&nand_info, CONFIG_ENV_OFFSET, CONFIG_ENV_SIZE,
 255                   (uchar *)CONFIG_NAND_ENV_DST);
 256
 257 #ifdef CONFIG_ENV_OFFSET_REDUND
 258         nand_load(&nand_info, CONFIG_ENV_OFFSET_REDUND, CONFIG_ENV_SIZE,
 259                   (uchar *)CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE);
 260 #endif
 261 #endif
 262
 263         if (nand_chip.select_chip)
 264                 nand_chip.select_chip(&nand_info, -1);
 265
 266         /*
 267          * Jump to U-Boot image
 268          */
 269         uboot = (void *)CONFIG_SYS_NAND_U_BOOT_START;
 270         (*uboot)();
 271 }