drivers/mtd/maps/tsunami_flash.c

   1 /*
   2  * tsunami_flash.c
   3  *
   4  * flash chip on alpha ds10...
   5  * $Id: tsunami_flash.c,v 1.6 2003/05/21 15:15:08 dwmw2 Exp $
   6  */
   7 #include <asm/io.h>
   8 #include <asm/core_tsunami.h>
   9 #include <linux/init.h>
  10 #include <linux/mtd/map.h>
  11 #include <linux/mtd/mtd.h>
  12
  13 #define FLASH_ENABLE_PORT 0x00C00001
  14 #define FLASH_ENABLE_BYTE 0x01
  15 #define FLASH_DISABLE_BYTE 0x00
  16
  17 #define MAX_TIG_FLASH_SIZE (12*1024*1024)
  18 static inline  __u8 tsunami_flash_read8(struct map_info *map, unsigned long offset)
  19 {
  20         return tsunami_tig_readb(offset);
  21 }
  22
  23 static void tsunami_flash_write8(struct map_info *map, __u8 value, unsigned long offset)
  24 {
  25         tsunami_tig_writeb(value, offset);
  26 }
  27
  28 static void tsunami_flash_copy_from(
  29         struct map_info *map, void *addr, unsigned long offset, ssize_t len)
  30 {
  31         unsigned char *dest;
  32         dest = addr;
  33         while(len && (offset < MAX_TIG_FLASH_SIZE)) {
  34                 *dest = tsunami_tig_readb(offset);
  35                 offset++;
  36                 dest++;
  37                 len--;
  38         }
  39 }
  40
  41 static void tsunami_flash_copy_to(
  42         struct map_info *map, unsigned long offset,
  43         const void *addr, ssize_t len)
  44 {
  45         const unsigned char *src;
  46         src = addr;
  47         while(len && (offset < MAX_TIG_FLASH_SIZE)) {
  48                 tsunami_tig_writeb(*src, offset);
  49                 offset++;
  50                 src++;
  51                 len--;
  52         }
  53 }
  54
  55 /*
  56  * Deliberately don't provide operations wider than 8 bits.  I don't
  57  * have then and it scares me to think how you could mess up if
  58  * you tried to use them.   Buswidth is correctly so I'm safe.
  59  */
  60 static struct map_info tsunami_flash_map = {
  61         .name = "flash chip on the Tsunami TIG bus",
  62         .size = MAX_TIG_FLASH_SIZE,
  63         .phys = NO_XIP;
  64         .buswidth = 1,
  65         .read8 = tsunami_flash_read8,
  66         .copy_from = tsunami_flash_copy_from,
  67         .write8 = tsunami_flash_write8,
  68         .copy_to = tsunami_flash_copy_to,
  69 };
  70
  71 static struct mtd_info *tsunami_flash_mtd;
  72
  73 static void __exit  cleanup_tsunami_flash(void)
  74 {
  75         struct mtd_info *mtd;
  76         mtd = tsunami_flash_mtd;
  77         if (mtd) {
  78                 del_mtd_device(mtd);
  79                 map_destroy(mtd);
  80         }
  81         tsunami_flash_mtd = 0;
  82 }
  83
  84
  85 static int __init init_tsunami_flash(void)
  86 {
  87         static const char *rom_probe_types[] = { "cfi_probe", "jedec_probe", "map_rom", 0 };
  88         char **type;
  89
  90         tsunami_tig_writeb(FLASH_ENABLE_BYTE, FLASH_ENABLE_PORT);
  91
  92         tsunami_flash_mtd = 0;
  93         type = rom_probe_types;
  94         for(; !tsunami_flash_mtd && *type; type++) {
  95                 tsunami_flash_mtd = do_map_probe(*type, &tsunami_flash_map);
  96         }
  97         if (tsunami_flash_mtd) {
  98                 tsunami_flash_mtd->owner = THIS_MODULE;
  99                 add_mtd_device(tsunami_flash_mtd);
 100                 return 0;
 101         }
 102         return -ENXIO;
 103 }
 104
 105 module_init(init_tsunami_flash);
 106 module_exit(cleanup_tsunami_flash);