1 /****************************************************************************/
4 * uclinux.c -- generic memory mapped MTD driver for uclinux
6 * (C) Copyright 2002, Greg Ungerer (gerg@snapgear.com)
9 /****************************************************************************/
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
17 #include <linux/major.h>
18 #include <linux/mtd/mtd.h>
19 #include <linux/mtd/map.h>
20 #include <linux/mtd/partitions.h>
22 #include <asm/sections.h>
24 /****************************************************************************/
26 struct map_info uclinux_ram_map
= {
28 .phys
= (unsigned long)__bss_stop
,
32 static struct mtd_info
*uclinux_ram_mtdinfo
;
34 /****************************************************************************/
36 static struct mtd_partition uclinux_romfs
[] = {
40 #define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs)
42 /****************************************************************************/
44 static int uclinux_point(struct mtd_info
*mtd
, loff_t from
, size_t len
,
45 size_t *retlen
, void **virt
, resource_size_t
*phys
)
47 struct map_info
*map
= mtd
->priv
;
48 *virt
= map
->virt
+ from
;
50 *phys
= map
->phys
+ from
;
55 /****************************************************************************/
57 static int __init
uclinux_mtd_init(void)
60 struct map_info
*mapp
;
62 mapp
= &uclinux_ram_map
;
64 mapp
->size
= PAGE_ALIGN(ntohl(*((unsigned long *)(mapp
->phys
+ 8))));
67 printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n",
68 (int) mapp
->phys
, (int) mapp
->size
);
71 * The filesystem is guaranteed to be in direct mapped memory. It is
72 * directly following the kernels own bss region. Following the same
73 * mechanism used by architectures setting up traditional initrds we
74 * use phys_to_virt to get the virtual address of its start.
76 mapp
->virt
= phys_to_virt(mapp
->phys
);
78 if (mapp
->virt
== 0) {
79 printk("uclinux[mtd]: no virtual mapping?\n");
83 simple_map_init(mapp
);
85 mtd
= do_map_probe("map_ram", mapp
);
87 printk("uclinux[mtd]: failed to find a mapping?\n");
91 mtd
->owner
= THIS_MODULE
;
92 mtd
->_point
= uclinux_point
;
95 uclinux_ram_mtdinfo
= mtd
;
96 mtd_device_register(mtd
, uclinux_romfs
, NUM_PARTITIONS
);
101 /****************************************************************************/
103 static void __exit
uclinux_mtd_cleanup(void)
105 if (uclinux_ram_mtdinfo
) {
106 mtd_device_unregister(uclinux_ram_mtdinfo
);
107 map_destroy(uclinux_ram_mtdinfo
);
108 uclinux_ram_mtdinfo
= NULL
;
110 if (uclinux_ram_map
.virt
)
111 uclinux_ram_map
.virt
= 0;
114 /****************************************************************************/
116 module_init(uclinux_mtd_init
);
117 module_exit(uclinux_mtd_cleanup
);
119 MODULE_LICENSE("GPL");
120 MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
121 MODULE_DESCRIPTION("Generic RAM based MTD for uClinux");
123 /****************************************************************************/