arch/arm/kernel/initrd-mtd.c

   1 /*
   2  * arch/arm/kernel/initrd-mtd.c
   3  *
   4  * MTD RAM platform device for the initrd
   5  *
   6  * Copyright (C) 2006 Philip Craig <philipc@snapgear.com>
   7  *
   8  */
   9
  10 #include <linux/platform_device.h>
  11 #include <linux/mtd/partitions.h>
  12 #include <linux/mtd/map.h>
  13 #include <linux/mtd/plat-ram.h>
  14
  15 extern unsigned long phys_initrd_start;
  16 extern unsigned long phys_initrd_size;
  17
  18 static struct resource initrd_mtd_ram_resource = {
  19         .flags          = IORESOURCE_MEM,
  20 };
  21
  22 static struct platdata_mtd_ram initrd_mtd_ram_data = {
  23         .mapname        = "Romfs",
  24         .root_dev       = 1,
  25 };
  26
  27 static struct platform_device initrd_mtd_ram_device = {
  28         .name                   = "mtd-ram",
  29         .id                     = 0,
  30         .dev.platform_data      = &initrd_mtd_ram_data,
  31         .num_resources          = 1,
  32         .resource               = &initrd_mtd_ram_resource,
  33 };
  34
  35 static int __init initrd_device_setup(void)
  36 {
  37         int ret = 0;
  38
  39         if (phys_initrd_start) {
  40                 if (map_bankwidth_supported(4))
  41                         initrd_mtd_ram_data.bankwidth = 4;
  42                 else if (map_bankwidth_supported(2))
  43                         initrd_mtd_ram_data.bankwidth = 2;
  44                 else
  45                         initrd_mtd_ram_data.bankwidth = 1;
  46                 initrd_mtd_ram_resource.start = phys_initrd_start;
  47                 initrd_mtd_ram_resource.end = phys_initrd_start
  48                         + phys_initrd_size - 1;
  49                 ret = platform_device_register(&initrd_mtd_ram_device);
  50         }
  51
  52         return ret;
  53 }
  54
  55 __initcall(initrd_device_setup);