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 1.1.1.1 2007/08/03 18:52:44 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/mtd/mtd.h>
20#include <linux/mtd/map.h>
21#include <linux/mtd/partitions.h>
22#include <asm/io.h>
23
24/****************************************************************************/
25
26struct map_info uclinux_ram_map = {
27	.name = "RAM",
28};
29
30struct mtd_info *uclinux_ram_mtdinfo;
31
32/****************************************************************************/
33
34struct mtd_partition uclinux_romfs[] = {
35	{ .name = "ROMfs" }
36};
37
38#define	NUM_PARTITIONS	ARRAY_SIZE(uclinux_romfs)
39
40/****************************************************************************/
41
42int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len,
43	size_t *retlen, u_char **mtdbuf)
44{
45	struct map_info *map = mtd->priv;
46	*mtdbuf = (u_char *) (map->virt + ((int) from));
47	*retlen = len;
48	return(0);
49}
50
51/****************************************************************************/
52
53int __init uclinux_mtd_init(void)
54{
55	struct mtd_info *mtd;
56	struct map_info *mapp;
57	extern char _ebss;
58	unsigned long addr = (unsigned long) &_ebss;
59
60	mapp = &uclinux_ram_map;
61	mapp->phys = addr;
62	mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(addr + 8))));
63	mapp->bankwidth = 4;
64
65	printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n",
66	       	(int) mapp->phys, (int) mapp->size);
67
68	mapp->virt = ioremap_nocache(mapp->phys, mapp->size);
69
70	if (mapp->virt == 0) {
71		printk("uclinux[mtd]: ioremap_nocache() failed\n");
72		return(-EIO);
73	}
74
75	simple_map_init(mapp);
76
77	mtd = do_map_probe("map_ram", mapp);
78	if (!mtd) {
79		printk("uclinux[mtd]: failed to find a mapping?\n");
80		iounmap(mapp->virt);
81		return(-ENXIO);
82	}
83
84	mtd->owner = THIS_MODULE;
85	mtd->point = uclinux_point;
86	mtd->priv = mapp;
87
88	uclinux_ram_mtdinfo = mtd;
89	add_mtd_partitions(mtd, uclinux_romfs, NUM_PARTITIONS);
90
91	return(0);
92}
93
94/****************************************************************************/
95
96void __exit uclinux_mtd_cleanup(void)
97{
98	if (uclinux_ram_mtdinfo) {
99		del_mtd_partitions(uclinux_ram_mtdinfo);
100		map_destroy(uclinux_ram_mtdinfo);
101		uclinux_ram_mtdinfo = NULL;
102	}
103	if (uclinux_ram_map.virt) {
104		iounmap((void *) uclinux_ram_map.virt);
105		uclinux_ram_map.virt = 0;
106	}
107}
108
109/****************************************************************************/
110
111module_init(uclinux_mtd_init);
112module_exit(uclinux_mtd_cleanup);
113
114MODULE_LICENSE("GPL");
115MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
116MODULE_DESCRIPTION("Generic RAM based MTD for uClinux");
117
118/****************************************************************************/
119