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 23 /****************************************************************************/ 24 25 extern char _ebss; 26 27 struct map_info uclinux_ram_map = { 28 .name = "RAM", 29 .phys = (unsigned long)&_ebss, 30 .size = 0, 31 }; 32 33 static struct mtd_info *uclinux_ram_mtdinfo; 34 35 /****************************************************************************/ 36 37 static struct mtd_partition uclinux_romfs[] = { 38 { .name = "ROMfs" } 39 }; 40 41 #define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs) 42 43 /****************************************************************************/ 44 45 static int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len, 46 size_t *retlen, void **virt, resource_size_t *phys) 47 { 48 struct map_info *map = mtd->priv; 49 *virt = map->virt + from; 50 if (phys) 51 *phys = map->phys + from; 52 *retlen = len; 53 return(0); 54 } 55 56 /****************************************************************************/ 57 58 static int __init uclinux_mtd_init(void) 59 { 60 struct mtd_info *mtd; 61 struct map_info *mapp; 62 63 mapp = &uclinux_ram_map; 64 if (!mapp->size) 65 mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(mapp->phys + 8)))); 66 mapp->bankwidth = 4; 67 68 printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n", 69 (int) mapp->phys, (int) mapp->size); 70 71 mapp->virt = ioremap_nocache(mapp->phys, mapp->size); 72 73 if (mapp->virt == 0) { 74 printk("uclinux[mtd]: ioremap_nocache() failed\n"); 75 return(-EIO); 76 } 77 78 simple_map_init(mapp); 79 80 mtd = do_map_probe("map_ram", mapp); 81 if (!mtd) { 82 printk("uclinux[mtd]: failed to find a mapping?\n"); 83 iounmap(mapp->virt); 84 return(-ENXIO); 85 } 86 87 mtd->owner = THIS_MODULE; 88 mtd->point = uclinux_point; 89 mtd->priv = mapp; 90 91 uclinux_ram_mtdinfo = mtd; 92 mtd_device_register(mtd, uclinux_romfs, NUM_PARTITIONS); 93 94 return(0); 95 } 96 97 /****************************************************************************/ 98 99 static void __exit uclinux_mtd_cleanup(void) 100 { 101 if (uclinux_ram_mtdinfo) { 102 mtd_device_unregister(uclinux_ram_mtdinfo); 103 map_destroy(uclinux_ram_mtdinfo); 104 uclinux_ram_mtdinfo = NULL; 105 } 106 if (uclinux_ram_map.virt) { 107 iounmap((void *) uclinux_ram_map.virt); 108 uclinux_ram_map.virt = 0; 109 } 110 } 111 112 /****************************************************************************/ 113 114 module_init(uclinux_mtd_init); 115 module_exit(uclinux_mtd_cleanup); 116 117 MODULE_LICENSE("GPL"); 118 MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>"); 119 MODULE_DESCRIPTION("Generic RAM based MTD for uClinux"); 120 121 /****************************************************************************/ 122