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| 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 | + * License: GPL |
| 9 | + */ |
| 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_ROM |
| 29 | +#define MAP_NAME "rom" |
| 30 | +#else |
| 31 | +#define MAP_NAME "ram" |
| 32 | +#endif |
| 33 | + |
| 34 | +static struct map_info uclinux_ram_map = { |
| 35 | + .name = MAP_NAME, |
| 36 | + .size = 0, |
| 37 | +}; |
| 38 | + |
| 39 | +static unsigned long physaddr = -1; |
| 40 | +module_param(physaddr, ulong, S_IRUGO); |
| 41 | + |
| 42 | +static struct mtd_info *uclinux_ram_mtdinfo; |
| 43 | + |
| 44 | +/****************************************************************************/ |
| 45 | + |
| 46 | +static const struct mtd_partition uclinux_romfs[] = { |
| 47 | + { .name = "ROMfs" } |
| 48 | +}; |
| 49 | + |
| 50 | +#define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs) |
| 51 | + |
| 52 | +/****************************************************************************/ |
| 53 | + |
| 54 | +static 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 | + |
| 67 | +static 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 | + else |
| 77 | + 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 is |
| 88 | + * directly following the kernels own bss region. Following the same |
| 89 | + * mechanism used by architectures setting up traditional initrds we |
| 90 | + * 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 | +} |
| 116 | +device_initcall(uclinux_mtd_init); |
| 117 | + |
| 118 | +/****************************************************************************/ |
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