| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 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 | /* |
| 35 | * Blackfin uses uclinux_ram_map during startup, so it must not be static. |
| 36 | * Provide a dummy declaration to make sparse happy. |
| 37 | */ |
| 38 | extern struct map_info uclinux_ram_map; |
| 39 | |
| 40 | struct map_info uclinux_ram_map = { |
| 41 | .name = MAP_NAME, |
| 42 | .size = 0, |
| 43 | }; |
| 44 | |
| 45 | static unsigned long physaddr = -1; |
| 46 | module_param(physaddr, ulong, S_IRUGO); |
| 47 | |
| 48 | static struct mtd_info *uclinux_ram_mtdinfo; |
| 49 | |
| 50 | /****************************************************************************/ |
| 51 | |
| 52 | static const struct mtd_partition uclinux_romfs[] = { |
| 53 | { .name = "ROMfs" } |
| 54 | }; |
| 55 | |
| 56 | #define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs) |
| 57 | |
| 58 | /****************************************************************************/ |
| 59 | |
| 60 | static int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len, |
| 61 | size_t *retlen, void **virt, resource_size_t *phys) |
| 62 | { |
| 63 | struct map_info *map = mtd->priv; |
| 64 | *virt = map->virt + from; |
| 65 | if (phys) |
| 66 | *phys = map->phys + from; |
| 67 | *retlen = len; |
| 68 | return(0); |
| 69 | } |
| 70 | |
| 71 | /****************************************************************************/ |
| 72 | |
| 73 | static int __init uclinux_mtd_init(void) |
| 74 | { |
| 75 | struct mtd_info *mtd; |
| 76 | struct map_info *mapp; |
| 77 | |
| 78 | mapp = &uclinux_ram_map; |
| 79 | |
| 80 | if (physaddr == -1) |
| 81 | mapp->phys = (resource_size_t)__bss_stop; |
| 82 | else |
| 83 | mapp->phys = physaddr; |
| 84 | |
| 85 | if (!mapp->size) |
| 86 | mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(mapp->phys + 8)))); |
| 87 | mapp->bankwidth = 4; |
| 88 | |
| 89 | printk("uclinux[mtd]: probe address=0x%x size=0x%x\n", |
| 90 | (int) mapp->phys, (int) mapp->size); |
| 91 | |
| 92 | /* |
| 93 | * The filesystem is guaranteed to be in direct mapped memory. It is |
| 94 | * directly following the kernels own bss region. Following the same |
| 95 | * mechanism used by architectures setting up traditional initrds we |
| 96 | * use phys_to_virt to get the virtual address of its start. |
| 97 | */ |
| 98 | mapp->virt = phys_to_virt(mapp->phys); |
| 99 | |
| 100 | if (mapp->virt == 0) { |
| 101 | printk("uclinux[mtd]: no virtual mapping?\n"); |
| 102 | return(-EIO); |
| 103 | } |
| 104 | |
| 105 | simple_map_init(mapp); |
| 106 | |
| 107 | mtd = do_map_probe("map_" MAP_NAME, mapp); |
| 108 | if (!mtd) { |
| 109 | printk("uclinux[mtd]: failed to find a mapping?\n"); |
| 110 | return(-ENXIO); |
| 111 | } |
| 112 | |
| 113 | mtd->owner = THIS_MODULE; |
| 114 | mtd->_point = uclinux_point; |
| 115 | mtd->priv = mapp; |
| 116 | |
| 117 | uclinux_ram_mtdinfo = mtd; |
| 118 | mtd_device_register(mtd, uclinux_romfs, NUM_PARTITIONS); |
| 119 | |
| 120 | return(0); |
| 121 | } |
| 122 | device_initcall(uclinux_mtd_init); |
| 123 | |
| 124 | /****************************************************************************/ |