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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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
28struct map_info uclinux_ram_map = {
29 .name = "RAM",
30};
31
32struct mtd_info *uclinux_ram_mtdinfo;
33
34/****************************************************************************/
35
36struct mtd_partition uclinux_romfs[] = {
37 { .name = "ROMfs" }
38};
39
40#define NUM_PARTITIONS (sizeof(uclinux_romfs) / sizeof(uclinux_romfs[0]))
41
42/****************************************************************************/
43
44int 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
55int __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
102void __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
117module_init(uclinux_mtd_init);
118module_exit(uclinux_mtd_cleanup);
119
120MODULE_LICENSE("GPL");
121MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
122MODULE_DESCRIPTION("Generic RAM based MTD for uClinux");
123
124/****************************************************************************/