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
9/****************************************************************************/
10
11#include <linux/module.h>
12#include <linux/types.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/fs.h>
16#include <linux/mm.h>
17#include <linux/major.h>
18#include <linux/mtd/mtd.h>
19#include <linux/mtd/map.h>
20#include <linux/mtd/partitions.h>
21#include <asm/io.h>
22
23/****************************************************************************/
24
25extern char _ebss;
26
27struct map_info uclinux_ram_map = {
28	.name = "RAM",
29	.phys = (unsigned long)&_ebss,
30	.size = 0,
31};
32
33static struct mtd_info *uclinux_ram_mtdinfo;
34
35/****************************************************************************/
36
37static struct mtd_partition uclinux_romfs[] = {
38	{ .name = "ROMfs" }
39};
40
41#define	NUM_PARTITIONS	ARRAY_SIZE(uclinux_romfs)
42
43/****************************************************************************/
44
45static int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len,
46	size_t *retlen, void **virt, resource_size_t *phys)
47{
48	struct map_info *map = mtd->priv;
49	*virt = map->virt + from;
50	if (phys)
51		*phys = map->phys + from;
52	*retlen = len;
53	return(0);
54}
55
56/****************************************************************************/
57
58static int __init uclinux_mtd_init(void)
59{
60	struct mtd_info *mtd;
61	struct map_info *mapp;
62
63	mapp = &uclinux_ram_map;
64	if (!mapp->size)
65		mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(mapp->phys + 8))));
66	mapp->bankwidth = 4;
67
68	printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n",
69	       	(int) mapp->phys, (int) mapp->size);
70
71	mapp->virt = ioremap_nocache(mapp->phys, mapp->size);
72
73	if (mapp->virt == 0) {
74		printk("uclinux[mtd]: ioremap_nocache() failed\n");
75		return(-EIO);
76	}
77
78	simple_map_init(mapp);
79
80	mtd = do_map_probe("map_ram", mapp);
81	if (!mtd) {
82		printk("uclinux[mtd]: failed to find a mapping?\n");
83		iounmap(mapp->virt);
84		return(-ENXIO);
85	}
86
87	mtd->owner = THIS_MODULE;
88	mtd->_point = uclinux_point;
89	mtd->priv = mapp;
90
91	uclinux_ram_mtdinfo = mtd;
92	mtd_device_register(mtd, uclinux_romfs, NUM_PARTITIONS);
93
94	return(0);
95}
96
97/****************************************************************************/
98
99static void __exit uclinux_mtd_cleanup(void)
100{
101	if (uclinux_ram_mtdinfo) {
102		mtd_device_unregister(uclinux_ram_mtdinfo);
103		map_destroy(uclinux_ram_mtdinfo);
104		uclinux_ram_mtdinfo = NULL;
105	}
106	if (uclinux_ram_map.virt) {
107		iounmap((void *) uclinux_ram_map.virt);
108		uclinux_ram_map.virt = 0;
109	}
110}
111
112/****************************************************************************/
113
114module_init(uclinux_mtd_init);
115module_exit(uclinux_mtd_cleanup);
116
117MODULE_LICENSE("GPL");
118MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
119MODULE_DESCRIPTION("Generic RAM based MTD for uClinux");
120
121/****************************************************************************/
122