nand_spl/nand_boot_fsl_nfc.c

   1 /*
   2  * (C) Copyright 2009
   3  * Magnus Lilja <lilja.magnus@gmail.com>
   4  *
   5  * (C) Copyright 2008
   6  * Maxim Artamonov, <scn1874 at yandex.ru>
   7  *
   8  * (C) Copyright 2006-2008
   9  * Stefan Roese, DENX Software Engineering, sr at denx.de.
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License as
  13  * published by the Free Software Foundation; either version 2 of
  14  * the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  24  * MA 02111-1307 USA
  25  */
  26
  27 #include <common.h>
  28 #include <nand.h>
  29 #include <asm-arm/arch/mx31-regs.h>
  30 #include <asm/io.h>
  31 #include <fsl_nfc.h>
  32
  33 static struct fsl_nfc_regs *nfc;
  34
  35 static void nfc_wait_ready(void)
  36 {
  37         uint32_t tmp;
  38
  39         while (!(readw(&nfc->nand_flash_config2) & NFC_INT))
  40                 ;
  41
  42         /* Reset interrupt flag */
  43         tmp = readw(&nfc->nand_flash_config2);
  44         tmp &= ~NFC_INT;
  45         writew(tmp, &nfc->nand_flash_config2);
  46 }
  47
  48 static void nfc_nand_init(void)
  49 {
  50         /* unlocking RAM Buff */
  51         writew(0x2, &nfc->configuration);
  52
  53         /* hardware ECC checking and correct */
  54         writew(NFC_ECC_EN, &nfc->nand_flash_config1);
  55 }
  56
  57 static void nfc_nand_command(unsigned short command)
  58 {
  59         writew(command, &nfc->flash_cmd);
  60         writew(NFC_CMD, &nfc->nand_flash_config2);
  61         nfc_wait_ready();
  62 }
  63
  64 static void nfc_nand_page_address(unsigned int page_address)
  65 {
  66         unsigned int page_count;
  67
  68         writew(0x00, &nfc->flash_cmd);
  69         writew(NFC_ADDR, &nfc->nand_flash_config2);
  70         nfc_wait_ready();
  71
  72         /* code only for 2kb flash */
  73         if (CONFIG_SYS_NAND_PAGE_SIZE == 0x800) {
  74                 writew(0x00, &nfc->flash_add);
  75                 writew(NFC_ADDR, &nfc->nand_flash_config2);
  76                 nfc_wait_ready();
  77         }
  78
  79         page_count = CONFIG_SYS_NAND_SIZE / CONFIG_SYS_NAND_PAGE_SIZE;
  80
  81         if (page_address <= page_count) {
  82                 page_count--; /* transform 0x01000000 to 0x00ffffff */
  83                 do {
  84                         writew(page_address & 0xff, &nfc->flash_add);
  85                         writew(NFC_ADDR, &nfc->nand_flash_config2);
  86                         nfc_wait_ready();
  87                         page_address = page_address >> 8;
  88                         page_count = page_count >> 8;
  89                 } while (page_count);
  90         }
  91 }
  92
  93 static void nfc_nand_data_output(void)
  94 {
  95         int i;
  96
  97         /*
  98          * The NAND controller requires four output commands for
  99          * large page devices.
 100          */
 101         for (i = 0; i < (CONFIG_SYS_NAND_PAGE_SIZE / 512); i++) {
 102                 writew(NFC_ECC_EN, &nfc->nand_flash_config1);
 103                 writew(i, &nfc->buffer_address); /* read in i:th buffer */
 104                 writew(NFC_OUTPUT, &nfc->nand_flash_config2);
 105                 nfc_wait_ready();
 106         }
 107 }
 108
 109 static int nfc_nand_check_ecc(void)
 110 {
 111         return readw(&nfc->ecc_status_result);
 112 }
 113
 114 static int nfc_read_page(unsigned int page_address, unsigned char *buf)
 115 {
 116         int i;
 117         u32 *src;
 118         u32 *dst;
 119
 120         writew(0, &nfc->buffer_address); /* read in first 0 buffer */
 121         nfc_nand_command(NAND_CMD_READ0);
 122         nfc_nand_page_address(page_address);
 123
 124         if (CONFIG_SYS_NAND_PAGE_SIZE == 0x800)
 125                 nfc_nand_command(NAND_CMD_READSTART);
 126
 127         nfc_nand_data_output(); /* fill the main buffer 0 */
 128
 129         if (nfc_nand_check_ecc())
 130                 return -1;
 131
 132         src = &nfc->main_area0[0];
 133         dst = (u32 *)buf;
 134
 135         /* main copy loop from NAND-buffer to SDRAM memory */
 136         for (i = 0; i < (CONFIG_SYS_NAND_PAGE_SIZE / 4); i++) {
 137                 writel(readl(src), dst);
 138                 src++;
 139                 dst++;
 140         }
 141
 142         return 0;
 143 }
 144
 145 static int is_badblock(int pagenumber)
 146 {
 147         int page = pagenumber;
 148         u32 badblock;
 149         u32 *src;
 150
 151         /* Check the first two pages for bad block markers */
 152         for (page = pagenumber; page < pagenumber + 2; page++) {
 153                 writew(0, &nfc->buffer_address); /* read in first 0 buffer */
 154                 nfc_nand_command(NAND_CMD_READ0);
 155                 nfc_nand_page_address(page);
 156
 157                 if (CONFIG_SYS_NAND_PAGE_SIZE == 0x800)
 158                         nfc_nand_command(NAND_CMD_READSTART);
 159
 160                 nfc_nand_data_output(); /* fill the main buffer 0 */
 161
 162                 src = &nfc->spare_area0[0];
 163
 164                 /*
 165                  * IMPORTANT NOTE: The nand flash controller uses a non-
 166                  * standard layout for large page devices. This can
 167                  * affect the position of the bad block marker.
 168                  */
 169                 /* Get the bad block marker */
 170                 badblock = readl(&src[CONFIG_SYS_NAND_BAD_BLOCK_POS / 4]);
 171                 badblock >>= 8 * (CONFIG_SYS_NAND_BAD_BLOCK_POS % 4);
 172                 badblock &= 0xff;
 173
 174                 /* bad block marker verify */
 175                 if (badblock != 0xff)
 176                         return 1; /* potential bad block */
 177         }
 178
 179         return 0;
 180 }
 181
 182 static int nand_load(unsigned int from, unsigned int size, unsigned char *buf)
 183 {
 184         int i;
 185         unsigned int page;
 186         unsigned int maxpages = CONFIG_SYS_NAND_SIZE /
 187                                 CONFIG_SYS_NAND_PAGE_SIZE;
 188
 189         nfc = (void *)NFC_BASE_ADDR;
 190
 191         nfc_nand_init();
 192
 193         /* Convert to page number */
 194         page = from / CONFIG_SYS_NAND_PAGE_SIZE;
 195         i = 0;
 196
 197         while (i < (size / CONFIG_SYS_NAND_PAGE_SIZE)) {
 198                 if (nfc_read_page(page, buf) < 0)
 199                         return -1;
 200
 201                 page++;
 202                 i++;
 203                 buf = buf + CONFIG_SYS_NAND_PAGE_SIZE;
 204
 205                 /*
 206                  * Check if we have crossed a block boundary, and if so
 207                  * check for bad block.
 208                  */
 209                 if (!(page % CONFIG_SYS_NAND_PAGE_COUNT)) {
 210                         /*
 211                          * Yes, new block. See if this block is good. If not,
 212                          * loop until we find i good block.
 213                          */
 214                         while (is_badblock(page)) {
 215                                 page = page + CONFIG_SYS_NAND_PAGE_COUNT;
 216                                 /* Check i we've reached the end of flash. */
 217                                 if (page >= maxpages)
 218                                         return -1;
 219                         }
 220                 }
 221         }
 222
 223         return 0;
 224 }
 225
 226 /*
 227  * The main entry for NAND booting. It's necessary that SDRAM is already
 228  * configured and available since this code loads the main U-Boot image
 229  * from NAND into SDRAM and starts it from there.
 230  */
 231 void nand_boot(void)
 232 {
 233         __attribute__((noreturn)) void (*uboot)(void);
 234
 235         nfc = (void *)NFC_BASE_ADDR;
 236
 237         /*
 238          * CONFIG_SYS_NAND_U_BOOT_OFFS and CONFIG_SYS_NAND_U_BOOT_SIZE must
 239          * be aligned to full pages
 240          */
 241         if (!nand_load(CONFIG_SYS_NAND_U_BOOT_OFFS, CONFIG_SYS_NAND_U_BOOT_SIZE,
 242                        (uchar *)CONFIG_SYS_NAND_U_BOOT_DST)) {
 243                 /* Copy from NAND successful, start U-boot */
 244                 uboot = (void *)CONFIG_SYS_NAND_U_BOOT_START;
 245                 uboot();
 246         } else {
 247                 /* Unrecoverable error when copying from NAND */
 248                 hang();
 249         }
 250 }
 251
 252 /*
 253  * Called in case of an exception.
 254  */
 255 void hang(void)
 256 {
 257         /* Loop forever */
 258         while (1) ;
 259 }