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/config.h> 14 #include <linux/module.h> 15 #include <linux/types.h> 16 #include <linux/init.h> 17 #include <linux/kernel.h> 18 #include <linux/fs.h> 19 #include <linux/major.h> 20 #include <linux/root_dev.h> 21 #include <linux/mtd/mtd.h> 22 #include <linux/mtd/map.h> 23 #include <linux/mtd/partitions.h> 24 #include <asm/io.h> 25 26 /****************************************************************************/ 27 28 struct map_info uclinux_ram_map = { 29 .name = "RAM", 30 }; 31 32 struct mtd_info *uclinux_ram_mtdinfo; 33 34 /****************************************************************************/ 35 36 struct mtd_partition uclinux_romfs[] = { 37 { .name = "ROMfs" } 38 }; 39 40 #define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs) 41 42 /****************************************************************************/ 43 44 int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len, 45 size_t *retlen, u_char **mtdbuf) 46 { 47 struct map_info *map = mtd->priv; 48 *mtdbuf = (u_char *) (map->virt + ((int) from)); 49 *retlen = len; 50 return(0); 51 } 52 53 /****************************************************************************/ 54 55 int __init uclinux_mtd_init(void) 56 { 57 struct mtd_info *mtd; 58 struct map_info *mapp; 59 extern char _ebss; 60 unsigned long addr = (unsigned long) &_ebss; 61 62 mapp = &uclinux_ram_map; 63 mapp->phys = addr; 64 mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(addr + 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 add_mtd_partitions(mtd, uclinux_romfs, NUM_PARTITIONS); 92 93 printk("uclinux[mtd]: set %s to be root filesystem\n", 94 uclinux_romfs[0].name); 95 ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, 0); 96 97 return(0); 98 } 99 100 /****************************************************************************/ 101 102 void __exit uclinux_mtd_cleanup(void) 103 { 104 if (uclinux_ram_mtdinfo) { 105 del_mtd_partitions(uclinux_ram_mtdinfo); 106 map_destroy(uclinux_ram_mtdinfo); 107 uclinux_ram_mtdinfo = NULL; 108 } 109 if (uclinux_ram_map.virt) { 110 iounmap((void *) uclinux_ram_map.virt); 111 uclinux_ram_map.virt = 0; 112 } 113 } 114 115 /****************************************************************************/ 116 117 module_init(uclinux_mtd_init); 118 module_exit(uclinux_mtd_cleanup); 119 120 MODULE_LICENSE("GPL"); 121 MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>"); 122 MODULE_DESCRIPTION("Generic RAM based MTD for uClinux"); 123 124 /****************************************************************************/ 125