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 /****************************************************************************/ 125