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 9 /****************************************************************************/ 10 11 #include <linux/module.h> 12 #include <linux/types.h> 13 #include <linux/init.h> 14 #include <linux/kernel.h> 15 #include <linux/fs.h> 16 #include <linux/mm.h> 17 #include <linux/major.h> 18 #include <linux/mtd/mtd.h> 19 #include <linux/mtd/map.h> 20 #include <linux/mtd/partitions.h> 21 #include <asm/io.h> 22 #include <asm/sections.h> 23 24 /****************************************************************************/ 25 26 struct map_info uclinux_ram_map = { 27 .name = "RAM", 28 .phys = (unsigned long)__bss_stop, 29 .size = 0, 30 }; 31 32 static struct mtd_info *uclinux_ram_mtdinfo; 33 34 /****************************************************************************/ 35 36 static struct mtd_partition uclinux_romfs[] = { 37 { .name = "ROMfs" } 38 }; 39 40 #define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs) 41 42 /****************************************************************************/ 43 44 static int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len, 45 size_t *retlen, void **virt, resource_size_t *phys) 46 { 47 struct map_info *map = mtd->priv; 48 *virt = map->virt + from; 49 if (phys) 50 *phys = map->phys + from; 51 *retlen = len; 52 return(0); 53 } 54 55 /****************************************************************************/ 56 57 static int __init uclinux_mtd_init(void) 58 { 59 struct mtd_info *mtd; 60 struct map_info *mapp; 61 62 mapp = &uclinux_ram_map; 63 if (!mapp->size) 64 mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(mapp->phys + 8)))); 65 mapp->bankwidth = 4; 66 67 printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n", 68 (int) mapp->phys, (int) mapp->size); 69 70 mapp->virt = ioremap_nocache(mapp->phys, mapp->size); 71 72 if (mapp->virt == 0) { 73 printk("uclinux[mtd]: ioremap_nocache() failed\n"); 74 return(-EIO); 75 } 76 77 simple_map_init(mapp); 78 79 mtd = do_map_probe("map_ram", mapp); 80 if (!mtd) { 81 printk("uclinux[mtd]: failed to find a mapping?\n"); 82 iounmap(mapp->virt); 83 return(-ENXIO); 84 } 85 86 mtd->owner = THIS_MODULE; 87 mtd->_point = uclinux_point; 88 mtd->priv = mapp; 89 90 uclinux_ram_mtdinfo = mtd; 91 mtd_device_register(mtd, uclinux_romfs, NUM_PARTITIONS); 92 93 return(0); 94 } 95 96 /****************************************************************************/ 97 98 static void __exit uclinux_mtd_cleanup(void) 99 { 100 if (uclinux_ram_mtdinfo) { 101 mtd_device_unregister(uclinux_ram_mtdinfo); 102 map_destroy(uclinux_ram_mtdinfo); 103 uclinux_ram_mtdinfo = NULL; 104 } 105 if (uclinux_ram_map.virt) { 106 iounmap((void *) uclinux_ram_map.virt); 107 uclinux_ram_map.virt = 0; 108 } 109 } 110 111 /****************************************************************************/ 112 113 module_init(uclinux_mtd_init); 114 module_exit(uclinux_mtd_cleanup); 115 116 MODULE_LICENSE("GPL"); 117 MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>"); 118 MODULE_DESCRIPTION("Generic RAM based MTD for uClinux"); 119 120 /****************************************************************************/ 121