xref: /openbmc/linux/drivers/mtd/maps/uclinux.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
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 
25 struct map_info uclinux_ram_map = {
26 	.name = "RAM",
27 };
28 
29 struct mtd_info *uclinux_ram_mtdinfo;
30 
31 /****************************************************************************/
32 
33 struct mtd_partition uclinux_romfs[] = {
34 	{ .name = "ROMfs" }
35 };
36 
37 #define	NUM_PARTITIONS	ARRAY_SIZE(uclinux_romfs)
38 
39 /****************************************************************************/
40 
41 int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len,
42 	size_t *retlen, void **virt, resource_size_t *phys)
43 {
44 	struct map_info *map = mtd->priv;
45 	*virt = map->virt + from;
46 	if (phys)
47 		*phys = map->phys + from;
48 	*retlen = len;
49 	return(0);
50 }
51 
52 /****************************************************************************/
53 
54 static int __init uclinux_mtd_init(void)
55 {
56 	struct mtd_info *mtd;
57 	struct map_info *mapp;
58 	extern char _ebss;
59 	unsigned long addr = (unsigned long) &_ebss;
60 
61 	mapp = &uclinux_ram_map;
62 	mapp->phys = addr;
63 	mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(addr + 8))));
64 	mapp->bankwidth = 4;
65 
66 	printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n",
67 	       	(int) mapp->phys, (int) mapp->size);
68 
69 	mapp->virt = ioremap_nocache(mapp->phys, mapp->size);
70 
71 	if (mapp->virt == 0) {
72 		printk("uclinux[mtd]: ioremap_nocache() failed\n");
73 		return(-EIO);
74 	}
75 
76 	simple_map_init(mapp);
77 
78 	mtd = do_map_probe("map_ram", mapp);
79 	if (!mtd) {
80 		printk("uclinux[mtd]: failed to find a mapping?\n");
81 		iounmap(mapp->virt);
82 		return(-ENXIO);
83 	}
84 
85 	mtd->owner = THIS_MODULE;
86 	mtd->point = uclinux_point;
87 	mtd->priv = mapp;
88 
89 	uclinux_ram_mtdinfo = mtd;
90 	add_mtd_partitions(mtd, uclinux_romfs, NUM_PARTITIONS);
91 
92 	return(0);
93 }
94 
95 /****************************************************************************/
96 
97 static void __exit uclinux_mtd_cleanup(void)
98 {
99 	if (uclinux_ram_mtdinfo) {
100 		del_mtd_partitions(uclinux_ram_mtdinfo);
101 		map_destroy(uclinux_ram_mtdinfo);
102 		uclinux_ram_mtdinfo = NULL;
103 	}
104 	if (uclinux_ram_map.virt) {
105 		iounmap((void *) uclinux_ram_map.virt);
106 		uclinux_ram_map.virt = 0;
107 	}
108 }
109 
110 /****************************************************************************/
111 
112 module_init(uclinux_mtd_init);
113 module_exit(uclinux_mtd_cleanup);
114 
115 MODULE_LICENSE("GPL");
116 MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
117 MODULE_DESCRIPTION("Generic RAM based MTD for uClinux");
118 
119 /****************************************************************************/
120