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1/****************************************************************************/2 3/*4 * uclinux.c -- generic memory mapped MTD driver for uclinux5 *6 * (C) Copyright 2002, Greg Ungerer (gerg@snapgear.com)7 *8 * License: GPL9 */10 11/****************************************************************************/12 13#include <linux/moduleparam.h>14#include <linux/types.h>15#include <linux/init.h>16#include <linux/kernel.h>17#include <linux/fs.h>18#include <linux/mm.h>19#include <linux/major.h>20#include <linux/mtd/mtd.h>21#include <linux/mtd/map.h>22#include <linux/mtd/partitions.h>23#include <asm/io.h>24#include <asm/sections.h>25 26/****************************************************************************/27 28#ifdef CONFIG_MTD_ROM29#define MAP_NAME "rom"30#else31#define MAP_NAME "ram"32#endif33 34static struct map_info uclinux_ram_map = {35 .name = MAP_NAME,36 .size = 0,37};38 39static unsigned long physaddr = -1;40module_param(physaddr, ulong, S_IRUGO);41 42static struct mtd_info *uclinux_ram_mtdinfo;43 44/****************************************************************************/45 46static const struct mtd_partition uclinux_romfs[] = {47 { .name = "ROMfs" }48};49 50#define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs)51 52/****************************************************************************/53 54static int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len,55 size_t *retlen, void **virt, resource_size_t *phys)56{57 struct map_info *map = mtd->priv;58 *virt = map->virt + from;59 if (phys)60 *phys = map->phys + from;61 *retlen = len;62 return(0);63}64 65/****************************************************************************/66 67static int __init uclinux_mtd_init(void)68{69 struct mtd_info *mtd;70 struct map_info *mapp;71 72 mapp = &uclinux_ram_map;73 74 if (physaddr == -1)75 mapp->phys = (resource_size_t)__bss_stop;76 else77 mapp->phys = physaddr;78 79 if (!mapp->size)80 mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(mapp->phys + 8))));81 mapp->bankwidth = 4;82 83 printk("uclinux[mtd]: probe address=0x%x size=0x%x\n",84 (int) mapp->phys, (int) mapp->size);85 86 /*87 * The filesystem is guaranteed to be in direct mapped memory. It is88 * directly following the kernels own bss region. Following the same89 * mechanism used by architectures setting up traditional initrds we90 * use phys_to_virt to get the virtual address of its start.91 */92 mapp->virt = phys_to_virt(mapp->phys);93 94 if (mapp->virt == 0) {95 printk("uclinux[mtd]: no virtual mapping?\n");96 return(-EIO);97 }98 99 simple_map_init(mapp);100 101 mtd = do_map_probe("map_" MAP_NAME, mapp);102 if (!mtd) {103 printk("uclinux[mtd]: failed to find a mapping?\n");104 return(-ENXIO);105 }106 107 mtd->owner = THIS_MODULE;108 mtd->_point = uclinux_point;109 mtd->priv = mapp;110 111 uclinux_ram_mtdinfo = mtd;112 mtd_device_register(mtd, uclinux_romfs, NUM_PARTITIONS);113 114 return(0);115}116device_initcall(uclinux_mtd_init);117 118/****************************************************************************/119