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 1.10 2005/01/05 18:05:13 dwmw2 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 29 /****************************************************************************/ 30 31 struct map_info uclinux_ram_map = { 32 .name = "RAM", 33 }; 34 35 struct mtd_info *uclinux_ram_mtdinfo; 36 37 /****************************************************************************/ 38 39 struct mtd_partition uclinux_romfs[] = { 40 { .name = "ROMfs" } 41 }; 42 43 #define NUM_PARTITIONS (sizeof(uclinux_romfs) / sizeof(uclinux_romfs[0])) 44 45 /****************************************************************************/ 46 47 int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len, 48 size_t *retlen, u_char **mtdbuf) 49 { 50 struct map_info *map = mtd->priv; 51 *mtdbuf = (u_char *) (map->virt + ((int) from)); 52 *retlen = len; 53 return(0); 54 } 55 56 /****************************************************************************/ 57 58 int __init uclinux_mtd_init(void) 59 { 60 struct mtd_info *mtd; 61 struct map_info *mapp; 62 extern char _ebss; 63 64 mapp = &uclinux_ram_map; 65 mapp->phys = (unsigned long) &_ebss; 66 mapp->size = PAGE_ALIGN(*((unsigned long *)((&_ebss) + 8))); 67 mapp->bankwidth = 4; 68 69 printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n", 70 (int) mapp->map_priv_2, (int) mapp->size); 71 72 mapp->virt = ioremap_nocache(mapp->phys, mapp->size); 73 74 if (mapp->virt == 0) { 75 printk("uclinux[mtd]: ioremap_nocache() failed\n"); 76 return(-EIO); 77 } 78 79 simple_map_init(mapp); 80 81 mtd = do_map_probe("map_ram", mapp); 82 if (!mtd) { 83 printk("uclinux[mtd]: failed to find a mapping?\n"); 84 iounmap(mapp->virt); 85 return(-ENXIO); 86 } 87 88 mtd->owner = THIS_MODULE; 89 mtd->point = uclinux_point; 90 mtd->priv = mapp; 91 92 uclinux_ram_mtdinfo = mtd; 93 add_mtd_partitions(mtd, uclinux_romfs, NUM_PARTITIONS); 94 95 printk("uclinux[mtd]: set %s to be root filesystem\n", 96 uclinux_romfs[0].name); 97 ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, 0); 98 put_mtd_device(mtd); 99 100 return(0); 101 } 102 103 /****************************************************************************/ 104 105 void __exit uclinux_mtd_cleanup(void) 106 { 107 if (uclinux_ram_mtdinfo) { 108 del_mtd_partitions(uclinux_ram_mtdinfo); 109 map_destroy(uclinux_ram_mtdinfo); 110 uclinux_ram_mtdinfo = NULL; 111 } 112 if (uclinux_ram_map.map_priv_1) { 113 iounmap((void *) uclinux_ram_map.virt); 114 uclinux_ram_map.virt = 0; 115 } 116 } 117 118 /****************************************************************************/ 119 120 module_init(uclinux_mtd_init); 121 module_exit(uclinux_mtd_cleanup); 122 123 MODULE_LICENSE("GPL"); 124 MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>"); 125 MODULE_DESCRIPTION("Generic RAM based MTD for uClinux"); 126 127 /****************************************************************************/ 128