onenand_ipl/onenand_read.c

   1 /*
   2  * (C) Copyright 2005-2009 Samsung Electronics
   3  * Kyungmin Park <kyungmin.park@samsung.com>
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <common.h>
  25
  26 #include <asm/io.h>
  27 #include <asm/string.h>
  28
  29 #include "onenand_ipl.h"
  30
  31 #define onenand_block_address(block)            (block)
  32 #define onenand_sector_address(page)            (page << 2)
  33 #define onenand_buffer_address()                ((1 << 3) << 8)
  34 #define onenand_bufferram_address(block)        (0)
  35
  36 #ifdef __HAVE_ARCH_MEMCPY32
  37 extern void *memcpy32(void *dest, void *src, int size);
  38 #endif
  39
  40 int (*onenand_read_page)(ulong block, ulong page, u_char *buf, int pagesize);
  41
  42 /* read a page with ECC */
  43 static int generic_onenand_read_page(ulong block, ulong page,
  44                                 u_char * buf, int pagesize)
  45 {
  46         unsigned long *base;
  47
  48 #ifndef __HAVE_ARCH_MEMCPY32
  49         unsigned int offset, value;
  50         unsigned long *p;
  51 #endif
  52
  53         onenand_writew(onenand_block_address(block),
  54                         ONENAND_REG_START_ADDRESS1);
  55
  56         onenand_writew(onenand_bufferram_address(block),
  57                         ONENAND_REG_START_ADDRESS2);
  58
  59         onenand_writew(onenand_sector_address(page),
  60                         ONENAND_REG_START_ADDRESS8);
  61
  62         onenand_writew(onenand_buffer_address(),
  63                         ONENAND_REG_START_BUFFER);
  64
  65         onenand_writew(ONENAND_INT_CLEAR, ONENAND_REG_INTERRUPT);
  66
  67         onenand_writew(ONENAND_CMD_READ, ONENAND_REG_COMMAND);
  68
  69 #ifndef __HAVE_ARCH_MEMCPY32
  70         p = (unsigned long *) buf;
  71 #endif
  72         base = (unsigned long *) (CONFIG_SYS_ONENAND_BASE + ONENAND_DATARAM);
  73
  74         while (!(READ_INTERRUPT() & ONENAND_INT_READ))
  75                 continue;
  76
  77         /* Check for invalid block mark */
  78         if (page < 2 && (onenand_readw(ONENAND_SPARERAM) != 0xffff))
  79                 return 1;
  80
  81 #ifdef __HAVE_ARCH_MEMCPY32
  82         /* 32 bytes boundary memory copy */
  83         memcpy32(buf, base, pagesize);
  84 #else
  85         for (offset = 0; offset < (pagesize >> 2); offset++) {
  86                 value = *(base + offset);
  87                 *p++ = value;
  88         }
  89 #endif
  90
  91         return 0;
  92 }
  93
  94 #ifndef CONFIG_ONENAND_START_PAGE
  95 #define CONFIG_ONENAND_START_PAGE       1
  96 #endif
  97 #define ONENAND_PAGES_PER_BLOCK         64
  98
  99 static void onenand_generic_init(int *page_is_4KiB, int *page)
 100 {
 101         int dev_id, density;
 102
 103         if (onenand_readw(ONENAND_REG_TECHNOLOGY))
 104                 *page_is_4KiB = 1;
 105         dev_id = onenand_readw(ONENAND_REG_DEVICE_ID);
 106         density = dev_id >> ONENAND_DEVICE_DENSITY_SHIFT;
 107         density &= ONENAND_DEVICE_DENSITY_MASK;
 108         if (density >= ONENAND_DEVICE_DENSITY_4Gb &&
 109             !(dev_id & ONENAND_DEVICE_IS_DDP))
 110                 *page_is_4KiB = 1;
 111 }
 112
 113 /**
 114  * onenand_read_block - Read CONFIG_SYS_MONITOR_LEN from begining
 115  *                      of OneNAND, skipping bad blocks
 116  * @return 0 on success
 117  */
 118 int onenand_read_block(unsigned char *buf)
 119 {
 120         int block, nblocks;
 121         int page = CONFIG_ONENAND_START_PAGE, offset = 0;
 122         int pagesize, erasesize, erase_shift;
 123         int page_is_4KiB = 0;
 124
 125         onenand_read_page = generic_onenand_read_page;
 126
 127         onenand_generic_init(&page_is_4KiB, &page);
 128
 129         if (page_is_4KiB) {
 130                 pagesize = 4096; /* OneNAND has 4KiB pagesize */
 131                 erase_shift = 18;
 132         } else {
 133                 pagesize = 2048; /* OneNAND has 2KiB pagesize */
 134                 erase_shift = 17;
 135         }
 136
 137         erasesize = (1 << erase_shift);
 138         nblocks = (CONFIG_SYS_MONITOR_LEN + erasesize - 1) >> erase_shift;
 139
 140         /* NOTE: you must read page from page 1 of block 0 */
 141         /* read the block page by page */
 142         for (block = 0; block < nblocks; block++) {
 143                 for (; page < ONENAND_PAGES_PER_BLOCK; page++) {
 144                         if (onenand_read_page(block, page, buf + offset,
 145                                                 pagesize)) {
 146                                 /* This block is bad. Skip it
 147                                  * and read next block */
 148                                 offset -= page * pagesize;
 149                                 nblocks++;
 150                                 break;
 151                         }
 152                         offset += pagesize;
 153                 }
 154                 page = 0;
 155         }
 156
 157         return 0;
 158 }