drivers/mtd/maps/uclinux.c

   1 /****************************************************************************/
   2
   3 /*
   4  *      uclinux.c -- generic memory mapped MTD driver for uclinux
   5  *
   6  *      (C) Copyright 2002, Greg Ungerer (gerg@snapgear.com)
   7  *
   8  *      $Id: uclinux.c,v 1.12 2005/11/07 11:14:29 gleixner Exp $
   9  */
  10
  11 /****************************************************************************/
  12
  13 #include <linux/module.h>
  14 #include <linux/types.h>
  15 #include <linux/init.h>
  16 #include <linux/kernel.h>
  17 #include <linux/fs.h>
  18 #include <linux/major.h>
  19 #include <linux/mtd/mtd.h>
  20 #include <linux/mtd/map.h>
  21 #include <linux/mtd/partitions.h>
  22 #include <asm/io.h>
  23
  24 /****************************************************************************/
  25
  26 struct map_info uclinux_ram_map = {
  27         .name = "RAM",
  28 };
  29
  30 struct mtd_info *uclinux_ram_mtdinfo;
  31
  32 /****************************************************************************/
  33
  34 struct mtd_partition uclinux_romfs[] = {
  35         { .name = "ROMfs" }
  36 };
  37
  38 #define NUM_PARTITIONS  ARRAY_SIZE(uclinux_romfs)
  39
  40 /****************************************************************************/
  41
  42 int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len,
  43         size_t *retlen, u_char **mtdbuf)
  44 {
  45         struct map_info *map = mtd->priv;
  46         *mtdbuf = (u_char *) (map->virt + ((int) from));
  47         *retlen = len;
  48         return(0);
  49 }
  50
  51 /****************************************************************************/
  52
  53 int __init uclinux_mtd_init(void)
  54 {
  55         struct mtd_info *mtd;
  56         struct map_info *mapp;
  57         extern char _ebss;
  58         unsigned long addr = (unsigned long) &_ebss;
  59
  60         mapp = &uclinux_ram_map;
  61         mapp->phys = addr;
  62         mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(addr + 8))));
  63         mapp->bankwidth = 4;
  64
  65         printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n",
  66                 (int) mapp->phys, (int) mapp->size);
  67
  68         mapp->virt = ioremap_nocache(mapp->phys, mapp->size);
  69
  70         if (mapp->virt == 0) {
  71                 printk("uclinux[mtd]: ioremap_nocache() failed\n");
  72                 return(-EIO);
  73         }
  74
  75         simple_map_init(mapp);
  76
  77         mtd = do_map_probe("map_ram", mapp);
  78         if (!mtd) {
  79                 printk("uclinux[mtd]: failed to find a mapping?\n");
  80                 iounmap(mapp->virt);
  81                 return(-ENXIO);
  82         }
  83
  84         mtd->owner = THIS_MODULE;
  85         mtd->point = uclinux_point;
  86         mtd->priv = mapp;
  87
  88         uclinux_ram_mtdinfo = mtd;
  89         add_mtd_partitions(mtd, uclinux_romfs, NUM_PARTITIONS);
  90
  91         return(0);
  92 }
  93
  94 /****************************************************************************/
  95
  96 void __exit uclinux_mtd_cleanup(void)
  97 {
  98         if (uclinux_ram_mtdinfo) {
  99                 del_mtd_partitions(uclinux_ram_mtdinfo);
 100                 map_destroy(uclinux_ram_mtdinfo);
 101                 uclinux_ram_mtdinfo = NULL;
 102         }
 103         if (uclinux_ram_map.virt) {
 104                 iounmap((void *) uclinux_ram_map.virt);
 105                 uclinux_ram_map.virt = 0;
 106         }
 107 }
 108
 109 /****************************************************************************/
 110
 111 module_init(uclinux_mtd_init);
 112 module_exit(uclinux_mtd_cleanup);
 113
 114 MODULE_LICENSE("GPL");
 115 MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
 116 MODULE_DESCRIPTION("Generic RAM based MTD for uClinux");
 117
 118 /****************************************************************************/