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 * $Id: uclinux.c,v 1.12 2005/11/07 11:14:29 gleixner Exp $ 9 */ 10 11 /****************************************************************************/ 12 13 #include <linux/module.h> 14 #include <linux/types.h> 15 #include <linux/init.h> 16 #include <linux/kernel.h> 17 #include <linux/fs.h> 18 #include <linux/major.h> 19 #include <linux/root_dev.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 25 /****************************************************************************/ 26 27 struct map_info uclinux_ram_map = { 28 .name = "RAM", 29 }; 30 31 struct mtd_info *uclinux_ram_mtdinfo; 32 33 /****************************************************************************/ 34 35 struct mtd_partition uclinux_romfs[] = { 36 { .name = "ROMfs" } 37 }; 38 39 #define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs) 40 41 /****************************************************************************/ 42 43 int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len, 44 size_t *retlen, u_char **mtdbuf) 45 { 46 struct map_info *map = mtd->priv; 47 *mtdbuf = (u_char *) (map->virt + ((int) from)); 48 *retlen = len; 49 return(0); 50 } 51 52 /****************************************************************************/ 53 54 int __init uclinux_mtd_init(void) 55 { 56 struct mtd_info *mtd; 57 struct map_info *mapp; 58 extern char _ebss; 59 unsigned long addr = (unsigned long) &_ebss; 60 61 mapp = &uclinux_ram_map; 62 mapp->phys = addr; 63 mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(addr + 8)))); 64 mapp->bankwidth = 4; 65 66 printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n", 67 (int) mapp->phys, (int) mapp->size); 68 69 mapp->virt = ioremap_nocache(mapp->phys, mapp->size); 70 71 if (mapp->virt == 0) { 72 printk("uclinux[mtd]: ioremap_nocache() failed\n"); 73 return(-EIO); 74 } 75 76 simple_map_init(mapp); 77 78 mtd = do_map_probe("map_ram", mapp); 79 if (!mtd) { 80 printk("uclinux[mtd]: failed to find a mapping?\n"); 81 iounmap(mapp->virt); 82 return(-ENXIO); 83 } 84 85 mtd->owner = THIS_MODULE; 86 mtd->point = uclinux_point; 87 mtd->priv = mapp; 88 89 uclinux_ram_mtdinfo = mtd; 90 add_mtd_partitions(mtd, uclinux_romfs, NUM_PARTITIONS); 91 92 printk("uclinux[mtd]: set %s to be root filesystem\n", 93 uclinux_romfs[0].name); 94 ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, 0); 95 96 return(0); 97 } 98 99 /****************************************************************************/ 100 101 void __exit uclinux_mtd_cleanup(void) 102 { 103 if (uclinux_ram_mtdinfo) { 104 del_mtd_partitions(uclinux_ram_mtdinfo); 105 map_destroy(uclinux_ram_mtdinfo); 106 uclinux_ram_mtdinfo = NULL; 107 } 108 if (uclinux_ram_map.virt) { 109 iounmap((void *) uclinux_ram_map.virt); 110 uclinux_ram_map.virt = 0; 111 } 112 } 113 114 /****************************************************************************/ 115 116 module_init(uclinux_mtd_init); 117 module_exit(uclinux_mtd_cleanup); 118 119 MODULE_LICENSE("GPL"); 120 MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>"); 121 MODULE_DESCRIPTION("Generic RAM based MTD for uClinux"); 122 123 /****************************************************************************/ 124