target/linux/ifxmips/files/drivers/mtd/maps/ifxmips.c

   1 /*
   2  *  Driver for IFXMIPS flashmap
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  *
  18  * Copyright (C) 2004 Liu Peng Infineon IFAP DC COM CPE
  19  * Copyright (C) 2007 John Crispin <blogic@openwrt.org>
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/types.h>
  24 #include <linux/kernel.h>
  25 #include <asm/io.h>
  26 #include <linux/init.h>
  27 #include <linux/mtd/mtd.h>
  28 #include <linux/mtd/map.h>
  29 #include <linux/mtd/partitions.h>
  30 #include <linux/mtd/cfi.h>
  31 #include <asm/ifxmips/ifxmips.h>
  32 #include <linux/magic.h>
  33 #include <linux/platform_device.h>
  34
  35 #define DRVNAME         "ifxmips_mtd"
  36
  37 static struct map_info
  38 ifxmips_map = {
  39         .name = DRVNAME,
  40         .bankwidth = 2,
  41         .size = 0x400000,
  42 };
  43
  44 static map_word
  45 ifxmips_read16 (struct map_info * map, unsigned long adr)
  46 {
  47         map_word temp;
  48
  49         adr ^= 2;
  50         temp.x[0] = *((__u16 *) (map->virt + adr));
  51
  52         return temp;
  53 }
  54
  55 static void
  56 ifxmips_write16 (struct map_info *map, map_word d, unsigned long adr)
  57 {
  58         adr ^= 2;
  59         *((__u16 *) (map->virt + adr)) = d.x[0];
  60 }
  61
  62 void
  63 ifxmips_copy_from (struct map_info *map, void *to, unsigned long from, ssize_t len)
  64 {
  65         u8 *p;
  66         u8 *to_8;
  67
  68         from = (unsigned long) (from + map->virt);
  69         p = (u8 *) from;
  70         to_8 = (u8 *) to;
  71         while(len--){
  72                 *to_8++ = *p++;
  73         }
  74 }
  75
  76 void
  77 ifxmips_copy_to (struct map_info *map, unsigned long to, const void *from, ssize_t len)
  78 {
  79         u8 *p =  (u8*) from;
  80         u8 *to_8;
  81
  82         to += (unsigned long) map->virt;
  83         to_8 = (u8*)to;
  84         while(len--){
  85                 *p++ = *to_8++;
  86         }
  87 }
  88
  89 static struct mtd_partition
  90 ifxmips_partitions[4] = {
  91         {
  92                 name:"U-Boot",
  93                 offset:0x00000000,
  94                 size:0x00020000,
  95         },
  96         {
  97                 name:"U-Boot-Env",
  98                 offset:0x00020000,
  99                 size:0x00010000,
 100         },
 101         {
 102                 name:"kernel",
 103                 offset:0x00030000,
 104                 size:0x0,
 105         },
 106         {
 107                 name:"rootfs",
 108                 offset:0x0,
 109                 size:0x0,
 110         },
 111 };
 112
 113 int
 114 find_uImage_size (unsigned long start_offset){
 115         unsigned long temp;
 116
 117         ifxmips_copy_from(&ifxmips_map, &temp, start_offset + 12, 4);
 118         printk(KERN_INFO DRVNAME ": kernel size is %ld \n", temp + 0x40);
 119         return temp + 0x40;
 120 }
 121
 122 int
 123 detect_squashfs_partition (unsigned long start_offset){
 124         unsigned long temp;
 125
 126         ifxmips_copy_from(&ifxmips_map, &temp, start_offset, 4);
 127
 128         return (temp == SQUASHFS_MAGIC);
 129 }
 130
 131 static int
 132 ifxmips_mtd_probe (void)
 133 {
 134         struct mtd_info *ifxmips_mtd = NULL;
 135         struct mtd_partition *parts = NULL;
 136         unsigned long uimage_size;
 137
 138         writel(0x1d7ff, IFXMIPS_EBU_BUSCON0);
 139
 140         ifxmips_map.read = ifxmips_read16;
 141         ifxmips_map.write = ifxmips_write16;
 142         ifxmips_map.copy_from = ifxmips_copy_from;
 143         ifxmips_map.copy_to = ifxmips_copy_to;
 144
 145         ifxmips_map.phys = IFXMIPS_FLASH_START;
 146         ifxmips_map.virt = ioremap_nocache(IFXMIPS_FLASH_START, IFXMIPS_FLASH_MAX);
 147         ifxmips_map.size = IFXMIPS_FLASH_MAX;
 148         if (!ifxmips_map.virt) {
 149                 printk(KERN_WARNING DRVNAME ": failed to ioremap!\n");
 150                 return -EIO;
 151         }
 152
 153         ifxmips_mtd = (struct mtd_info *) do_map_probe("cfi_probe", &ifxmips_map);
 154         if (!ifxmips_mtd) {
 155                 iounmap(ifxmips_map.virt);
 156                 printk(KERN_WARNING DRVNAME ": probing failed\n");
 157                 return -ENXIO;
 158         }
 159
 160         ifxmips_mtd->owner = THIS_MODULE;
 161
 162         uimage_size = find_uImage_size(ifxmips_partitions[2].offset);
 163
 164         if(detect_squashfs_partition(ifxmips_partitions[2].offset + uimage_size)){
 165                 printk(KERN_INFO DRVNAME ": found a squashfs following the uImage\n");
 166         } else {
 167                 uimage_size &= ~0xffff;
 168                 uimage_size += 0x10000;
 169         }
 170
 171         ifxmips_partitions[2].size = uimage_size;
 172         ifxmips_partitions[3].offset = ifxmips_partitions[2].offset + ifxmips_partitions[2].size;
 173         ifxmips_partitions[3].size = ((ifxmips_mtd->size >> 20) * 1024 * 1024) - ifxmips_partitions[3].offset;
 174
 175         parts = &ifxmips_partitions[0];
 176         add_mtd_partitions(ifxmips_mtd, parts, 4);
 177
 178         printk(KERN_INFO DRVNAME ": added ifxmips flash with %dMB\n", ifxmips_mtd->size >> 20);
 179         return 0;
 180 }
 181
 182 static struct
 183 platform_driver ifxmips_mtd_driver = {
 184         .probe = ifxmips_mtd_probe,
 185         .driver = {
 186                 .name = DRVNAME,
 187                 .owner = THIS_MODULE,
 188         },
 189 };
 190
 191 int __init
 192 init_ifxmips_mtd (void)
 193 {
 194         int ret = platform_driver_register(&ifxmips_mtd_driver);
 195         if (ret)
 196                 printk(KERN_INFO DRVNAME ": error registering platfom driver!");
 197
 198         return ret;
 199 }
 200
 201 static void
 202 __exit
 203 cleanup_ifxmips_mtd (void)
 204 {
 205         platform_driver_unregister(&ifxmips_mtd_driver);
 206 }
 207
 208 module_init (init_ifxmips_mtd);
 209 module_exit (cleanup_ifxmips_mtd);
 210
 211 MODULE_LICENSE ("GPL");
 212 MODULE_AUTHOR ("John Crispin <blogic@openwrt.org>");
 213 MODULE_DESCRIPTION ("MTD map driver for IFXMIPS boards");