drivers/mtd/maps/db1x00-flash.c

   1 /*
   2  * Flash memory access on Alchemy Db1xxx boards
   3  *
   4  * $Id: db1x00-flash.c,v 1.3 2004/07/14 17:45:40 dwmw2 Exp $
   5  *
   6  * (C) 2003 Pete Popov <ppopov@pacbell.net>
   7  *
   8  */
   9
  10 #include <linux/config.h>
  11 #include <linux/module.h>
  12 #include <linux/types.h>
  13 #include <linux/init.h>
  14 #include <linux/kernel.h>
  15
  16 #include <linux/mtd/mtd.h>
  17 #include <linux/mtd/map.h>
  18 #include <linux/mtd/partitions.h>
  19
  20 #include <asm/io.h>
  21 #include <asm/au1000.h>
  22 #include <asm/db1x00.h>
  23
  24 #ifdef  DEBUG_RW
  25 #define DBG(x...)       printk(x)
  26 #else
  27 #define DBG(x...)
  28 #endif
  29
  30 static unsigned long window_addr;
  31 static unsigned long window_size;
  32 static unsigned long flash_size;
  33
  34 static BCSR * const bcsr = (BCSR *)0xAE000000;
  35 static unsigned char flash_bankwidth = 4;
  36
  37 /*
  38  * The Db1x boards support different flash densities. We setup
  39  * the mtd_partition structures below for default of 64Mbit
  40  * flash densities, and override the partitions sizes, if
  41  * necessary, after we check the board status register.
  42  */
  43
  44 #ifdef DB1X00_BOTH_BANKS
  45 /* both banks will be used. Combine the first bank and the first
  46  * part of the second bank together into a single jffs/jffs2
  47  * partition.
  48  */
  49 static struct mtd_partition db1x00_partitions[] = {
  50         {
  51                 .name         =  "User FS",
  52                 .size         =  0x1c00000,
  53                 .offset       =  0x0000000
  54         },{
  55                 .name         =  "yamon",
  56                 .size         =  0x0100000,
  57                 .offset       =  MTDPART_OFS_APPEND,
  58                 .mask_flags   =  MTD_WRITEABLE
  59         },{
  60                 .name         =  "raw kernel",
  61                 .size         =  (0x300000-0x40000), /* last 256KB is env */
  62                 .offset       =  MTDPART_OFS_APPEND,
  63         }
  64 };
  65 #elif defined(DB1X00_BOOT_ONLY)
  66 static struct mtd_partition db1x00_partitions[] = {
  67         {
  68                 .name         =  "User FS",
  69                 .size         =  0x00c00000,
  70                 .offset       =  0x0000000
  71         },{
  72                 .name         =  "yamon",
  73                 .size         =  0x0100000,
  74                 .offset       =  MTDPART_OFS_APPEND,
  75                 .mask_flags   =  MTD_WRITEABLE
  76         },{
  77                 .name         =  "raw kernel",
  78                 .size         =  (0x300000-0x40000), /* last 256KB is env */
  79                 .offset       =  MTDPART_OFS_APPEND,
  80         }
  81 };
  82 #elif defined(DB1X00_USER_ONLY)
  83 static struct mtd_partition db1x00_partitions[] = {
  84         {
  85                 .name         =  "User FS",
  86                 .size         =  0x0e00000,
  87                 .offset       =  0x0000000
  88         },{
  89                 .name         =  "raw kernel",
  90                 .size         =  MTDPART_SIZ_FULL,
  91                 .offset       =  MTDPART_OFS_APPEND,
  92         }
  93 };
  94 #else
  95 #error MTD_DB1X00 define combo error /* should never happen */
  96 #endif
  97 #define NB_OF(x)  (sizeof(x)/sizeof(x[0]))
  98
  99 #define NAME            "Db1x00 Linux Flash"
 100
 101 static struct map_info db1xxx_mtd_map = {
 102         .name           = NAME,
 103 };
 104
 105 static struct mtd_partition *parsed_parts;
 106 static struct mtd_info *db1xxx_mtd;
 107
 108 /*
 109  * Probe the flash density and setup window address and size
 110  * based on user CONFIG options. There are times when we don't
 111  * want the MTD driver to be probing the boot or user flash,
 112  * so having the option to enable only one bank is important.
 113  */
 114 int setup_flash_params(void)
 115 {
 116         switch ((bcsr->status >> 14) & 0x3) {
 117                 case 0: /* 64Mbit devices */
 118                         flash_size = 0x800000; /* 8MB per part */
 119 #if defined(DB1X00_BOTH_BANKS)
 120                         window_addr = 0x1E000000;
 121                         window_size = 0x2000000;
 122 #elif defined(DB1X00_BOOT_ONLY)
 123                         window_addr = 0x1F000000;
 124                         window_size = 0x1000000;
 125 #else /* USER ONLY */
 126                         window_addr = 0x1E000000;
 127                         window_size = 0x1000000;
 128 #endif
 129                         break;
 130                 case 1:
 131                         /* 128 Mbit devices */
 132                         flash_size = 0x1000000; /* 16MB per part */
 133 #if defined(DB1X00_BOTH_BANKS)
 134                         window_addr = 0x1C000000;
 135                         window_size = 0x4000000;
 136                         /* USERFS from 0x1C00 0000 to 0x1FC0 0000 */
 137                         db1x00_partitions[0].size = 0x3C00000;
 138 #elif defined(DB1X00_BOOT_ONLY)
 139                         window_addr = 0x1E000000;
 140                         window_size = 0x2000000;
 141                         /* USERFS from 0x1E00 0000 to 0x1FC0 0000 */
 142                         db1x00_partitions[0].size = 0x1C00000;
 143 #else /* USER ONLY */
 144                         window_addr = 0x1C000000;
 145                         window_size = 0x2000000;
 146                         /* USERFS from 0x1C00 0000 to 0x1DE00000 */
 147                         db1x00_partitions[0].size = 0x1DE0000;
 148 #endif
 149                         break;
 150                 case 2:
 151                         /* 256 Mbit devices */
 152                         flash_size = 0x4000000; /* 64MB per part */
 153 #if defined(DB1X00_BOTH_BANKS)
 154                         return 1;
 155 #elif defined(DB1X00_BOOT_ONLY)
 156                         /* Boot ROM flash bank only; no user bank */
 157                         window_addr = 0x1C000000;
 158                         window_size = 0x4000000;
 159                         /* USERFS from 0x1C00 0000 to 0x1FC00000 */
 160                         db1x00_partitions[0].size = 0x3C00000;
 161 #else /* USER ONLY */
 162                         return 1;
 163 #endif
 164                         break;
 165                 default:
 166                         return 1;
 167         }
 168         db1xxx_mtd_map.size = window_size;
 169         db1xxx_mtd_map.bankwidth = flash_bankwidth;
 170         db1xxx_mtd_map.phys = window_addr;
 171         db1xxx_mtd_map.bankwidth = flash_bankwidth;
 172         return 0;
 173 }
 174
 175 int __init db1x00_mtd_init(void)
 176 {
 177         struct mtd_partition *parts;
 178         int nb_parts = 0;
 179
 180         if (setup_flash_params())
 181                 return -ENXIO;
 182
 183         /*
 184          * Static partition definition selection
 185          */
 186         parts = db1x00_partitions;
 187         nb_parts = NB_OF(db1x00_partitions);
 188
 189         /*
 190          * Now let's probe for the actual flash.  Do it here since
 191          * specific machine settings might have been set above.
 192          */
 193         printk(KERN_NOTICE "Db1xxx flash: probing %d-bit flash bus\n",
 194                         db1xxx_mtd_map.bankwidth*8);
 195         db1xxx_mtd_map.virt = (unsigned long)ioremap(window_addr, window_size);
 196         db1xxx_mtd = do_map_probe("cfi_probe", &db1xxx_mtd_map);
 197         if (!db1xxx_mtd) return -ENXIO;
 198         db1xxx_mtd->owner = THIS_MODULE;
 199
 200         add_mtd_partitions(db1xxx_mtd, parts, nb_parts);
 201         return 0;
 202 }
 203
 204 static void __exit db1x00_mtd_cleanup(void)
 205 {
 206         if (db1xxx_mtd) {
 207                 del_mtd_partitions(db1xxx_mtd);
 208                 map_destroy(db1xxx_mtd);
 209                 if (parsed_parts)
 210                         kfree(parsed_parts);
 211         }
 212 }
 213
 214 module_init(db1x00_mtd_init);
 215 module_exit(db1x00_mtd_cleanup);
 216
 217 MODULE_AUTHOR("Pete Popov");
 218 MODULE_DESCRIPTION("Db1x00 mtd map driver");
 219 MODULE_LICENSE("GPL");