drivers/mtd/maps/vmax301.c

   1 // $Id: vmax301.c,v 1.30 2004/07/12 22:38:29 dwmw2 Exp $
   2 /* ######################################################################
   3
   4    Tempustech VMAX SBC301 MTD Driver.
   5
   6    The VMAx 301 is a SBC based on . It
   7    comes with three builtin AMD 29F016B flash chips and a socket for SRAM or
   8    more flash. Each unit has it's own 8k mapping into a settable region
   9    (0xD8000). There are two 8k mappings for each MTD, the first is always set
  10    to the lower 8k of the device the second is paged. Writing a 16 bit page
  11    value to anywhere in the first 8k will cause the second 8k to page around.
  12
  13    To boot the device a bios extension must be installed into the first 8k
  14    of flash that is smart enough to copy itself down, page in the rest of
  15    itself and begin executing.
  16
  17    ##################################################################### */
  18
  19 #include <linux/module.h>
  20 #include <linux/slab.h>
  21 #include <linux/ioport.h>
  22 #include <linux/init.h>
  23 #include <linux/spinlock.h>
  24 #include <asm/io.h>
  25
  26 #include <linux/mtd/map.h>
  27 #include <linux/mtd/mtd.h>
  28
  29
  30 #define WINDOW_START 0xd8000
  31 #define WINDOW_LENGTH 0x2000
  32 #define WINDOW_SHIFT 25
  33 #define WINDOW_MASK 0x1FFF
  34
  35 /* Actually we could use two spinlocks, but we'd have to have
  36    more private space in the struct map_info. We lose a little
  37    performance like this, but we'd probably lose more by having
  38    the extra indirection from having one of the map->map_priv
  39    fields pointing to yet another private struct.
  40 */
  41 static spinlock_t vmax301_spin = SPIN_LOCK_UNLOCKED;
  42
  43 static void __vmax301_page(struct map_info *map, unsigned long page)
  44 {
  45         writew(page, map->map_priv_2 - WINDOW_LENGTH);
  46         map->map_priv_1 = page;
  47 }
  48
  49 static inline void vmax301_page(struct map_info *map,
  50                                   unsigned long ofs)
  51 {
  52         unsigned long page = (ofs >> WINDOW_SHIFT);
  53         if (map->map_priv_1 != page)
  54                 __vmax301_page(map, page);
  55 }
  56
  57 static map_word vmax301_read8(struct map_info *map, unsigned long ofs)
  58 {
  59         map_word ret;
  60         spin_lock(&vmax301_spin);
  61         vmax301_page(map, ofs);
  62         ret.x[0] = readb(map->map_priv_2 + (ofs & WINDOW_MASK));
  63         spin_unlock(&vmax301_spin);
  64         return ret;
  65 }
  66
  67 static void vmax301_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
  68 {
  69         while(len) {
  70                 unsigned long thislen = len;
  71                 if (len > (WINDOW_LENGTH - (from & WINDOW_MASK)))
  72                         thislen = WINDOW_LENGTH-(from & WINDOW_MASK);
  73                 spin_lock(&vmax301_spin);
  74                 vmax301_page(map, from);
  75                 memcpy_fromio(to, map->map_priv_2 + from, thislen);
  76                 spin_unlock(&vmax301_spin);
  77                 to += thislen;
  78                 from += thislen;
  79                 len -= thislen;
  80         }
  81 }
  82
  83 static void vmax301_write8(struct map_info *map, map_word d, unsigned long adr)
  84 {
  85         spin_lock(&vmax301_spin);
  86         vmax301_page(map, adr);
  87         writeb(d.x[0], map->map_priv_2 + (adr & WINDOW_MASK));
  88         spin_unlock(&vmax301_spin);
  89 }
  90
  91 static void vmax301_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
  92 {
  93         while(len) {
  94                 unsigned long thislen = len;
  95                 if (len > (WINDOW_LENGTH - (to & WINDOW_MASK)))
  96                         thislen = WINDOW_LENGTH-(to & WINDOW_MASK);
  97
  98                 spin_lock(&vmax301_spin);
  99                 vmax301_page(map, to);
 100                 memcpy_toio(map->map_priv_2 + to, from, thislen);
 101                 spin_unlock(&vmax301_spin);
 102                 to += thislen;
 103                 from += thislen;
 104                 len -= thislen;
 105         }
 106 }
 107
 108 static struct map_info vmax_map[2] = {
 109         {
 110                 .name = "VMAX301 Internal Flash",
 111                 .phys = NO_XIP,
 112                 .size = 3*2*1024*1024,
 113                 .bankwidth = 1,
 114                 .read = vmax301_read8,
 115                 .copy_from = vmax301_copy_from,
 116                 .write = vmax301_write8,
 117                 .copy_to = vmax301_copy_to,
 118                 .map_priv_1 = WINDOW_START + WINDOW_LENGTH,
 119                 .map_priv_2 = 0xFFFFFFFF
 120         },
 121         {
 122                 .name = "VMAX301 Socket",
 123                 .phys = NO_XIP,
 124                 .size = 0,
 125                 .bankwidth = 1,
 126                 .read = vmax301_read8,
 127                 .copy_from = vmax301_copy_from,
 128                 .write = vmax301_write8,
 129                 .copy_to = vmax301_copy_to,
 130                 .map_priv_1 = WINDOW_START + (3*WINDOW_LENGTH),
 131                 .map_priv_2 = 0xFFFFFFFF
 132         }
 133 };
 134
 135 static struct mtd_info *vmax_mtd[2] = {NULL, NULL};
 136
 137 static void __exit cleanup_vmax301(void)
 138 {
 139         int i;
 140
 141         for (i=0; i<2; i++) {
 142                 if (vmax_mtd[i]) {
 143                         del_mtd_device(vmax_mtd[i]);
 144                         map_destroy(vmax_mtd[i]);
 145                 }
 146         }
 147         iounmap((void *)vmax_map[0].map_priv_1 - WINDOW_START);
 148 }
 149
 150 int __init init_vmax301(void)
 151 {
 152         int i;
 153         unsigned long iomapadr;
 154         // Print out our little header..
 155         printk("Tempustech VMAX 301 MEM:0x%x-0x%x\n",WINDOW_START,
 156                WINDOW_START+4*WINDOW_LENGTH);
 157
 158         iomapadr = (unsigned long)ioremap(WINDOW_START, WINDOW_LENGTH*4);
 159         if (!iomapadr) {
 160                 printk("Failed to ioremap memory region\n");
 161                 return -EIO;
 162         }
 163         /* Put the address in the map's private data area.
 164            We store the actual MTD IO address rather than the
 165            address of the first half, because it's used more
 166            often.
 167         */
 168         vmax_map[0].map_priv_2 = iomapadr + WINDOW_START;
 169         vmax_map[1].map_priv_2 = iomapadr + (3*WINDOW_START);
 170
 171         for (i=0; i<2; i++) {
 172                 vmax_mtd[i] = do_map_probe("cfi_probe", &vmax_map[i]);
 173                 if (!vmax_mtd[i])
 174                         vmax_mtd[i] = do_map_probe("jedec", &vmax_map[i]);
 175                 if (!vmax_mtd[i])
 176                         vmax_mtd[i] = do_map_probe("map_ram", &vmax_map[i]);
 177                 if (!vmax_mtd[i])
 178                         vmax_mtd[i] = do_map_probe("map_rom", &vmax_map[i]);
 179                 if (vmax_mtd[i]) {
 180                         vmax_mtd[i]->owner = THIS_MODULE;
 181                         add_mtd_device(vmax_mtd[i]);
 182                 }
 183         }
 184
 185         if (!vmax_mtd[1] && !vmax_mtd[2]) {
 186                 iounmap((void *)iomapadr);
 187                 return -ENXIO;
 188         }
 189
 190         return 0;
 191 }
 192
 193 module_init(init_vmax301);
 194 module_exit(cleanup_vmax301);
 195
 196 MODULE_LICENSE("GPL");
 197 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 198 MODULE_DESCRIPTION("MTD map driver for Tempustech VMAX SBC301 board");