1*4882a593Smuzhiyun /****************************************************************************/
2*4882a593Smuzhiyun
3*4882a593Smuzhiyun /*
4*4882a593Smuzhiyun * uclinux.c -- generic memory mapped MTD driver for uclinux
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * (C) Copyright 2002, Greg Ungerer (gerg@snapgear.com)
7*4882a593Smuzhiyun *
8*4882a593Smuzhiyun * License: GPL
9*4882a593Smuzhiyun */
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun /****************************************************************************/
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun #include <linux/moduleparam.h>
14*4882a593Smuzhiyun #include <linux/types.h>
15*4882a593Smuzhiyun #include <linux/init.h>
16*4882a593Smuzhiyun #include <linux/kernel.h>
17*4882a593Smuzhiyun #include <linux/fs.h>
18*4882a593Smuzhiyun #include <linux/mm.h>
19*4882a593Smuzhiyun #include <linux/major.h>
20*4882a593Smuzhiyun #include <linux/mtd/mtd.h>
21*4882a593Smuzhiyun #include <linux/mtd/map.h>
22*4882a593Smuzhiyun #include <linux/mtd/partitions.h>
23*4882a593Smuzhiyun #include <asm/io.h>
24*4882a593Smuzhiyun #include <asm/sections.h>
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun /****************************************************************************/
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun #ifdef CONFIG_MTD_ROM
29*4882a593Smuzhiyun #define MAP_NAME "rom"
30*4882a593Smuzhiyun #else
31*4882a593Smuzhiyun #define MAP_NAME "ram"
32*4882a593Smuzhiyun #endif
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun static struct map_info uclinux_ram_map = {
35*4882a593Smuzhiyun .name = MAP_NAME,
36*4882a593Smuzhiyun .size = 0,
37*4882a593Smuzhiyun };
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun static unsigned long physaddr = -1;
40*4882a593Smuzhiyun module_param(physaddr, ulong, S_IRUGO);
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun static struct mtd_info *uclinux_ram_mtdinfo;
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun /****************************************************************************/
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun static const struct mtd_partition uclinux_romfs[] = {
47*4882a593Smuzhiyun { .name = "ROMfs" }
48*4882a593Smuzhiyun };
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun #define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs)
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun /****************************************************************************/
53*4882a593Smuzhiyun
uclinux_point(struct mtd_info * mtd,loff_t from,size_t len,size_t * retlen,void ** virt,resource_size_t * phys)54*4882a593Smuzhiyun static int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len,
55*4882a593Smuzhiyun size_t *retlen, void **virt, resource_size_t *phys)
56*4882a593Smuzhiyun {
57*4882a593Smuzhiyun struct map_info *map = mtd->priv;
58*4882a593Smuzhiyun *virt = map->virt + from;
59*4882a593Smuzhiyun if (phys)
60*4882a593Smuzhiyun *phys = map->phys + from;
61*4882a593Smuzhiyun *retlen = len;
62*4882a593Smuzhiyun return(0);
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun /****************************************************************************/
66*4882a593Smuzhiyun
uclinux_mtd_init(void)67*4882a593Smuzhiyun static int __init uclinux_mtd_init(void)
68*4882a593Smuzhiyun {
69*4882a593Smuzhiyun struct mtd_info *mtd;
70*4882a593Smuzhiyun struct map_info *mapp;
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun mapp = &uclinux_ram_map;
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun if (physaddr == -1)
75*4882a593Smuzhiyun mapp->phys = (resource_size_t)__bss_stop;
76*4882a593Smuzhiyun else
77*4882a593Smuzhiyun mapp->phys = physaddr;
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun if (!mapp->size)
80*4882a593Smuzhiyun mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(mapp->phys + 8))));
81*4882a593Smuzhiyun mapp->bankwidth = 4;
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun printk("uclinux[mtd]: probe address=0x%x size=0x%x\n",
84*4882a593Smuzhiyun (int) mapp->phys, (int) mapp->size);
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun /*
87*4882a593Smuzhiyun * The filesystem is guaranteed to be in direct mapped memory. It is
88*4882a593Smuzhiyun * directly following the kernels own bss region. Following the same
89*4882a593Smuzhiyun * mechanism used by architectures setting up traditional initrds we
90*4882a593Smuzhiyun * use phys_to_virt to get the virtual address of its start.
91*4882a593Smuzhiyun */
92*4882a593Smuzhiyun mapp->virt = phys_to_virt(mapp->phys);
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun if (mapp->virt == 0) {
95*4882a593Smuzhiyun printk("uclinux[mtd]: no virtual mapping?\n");
96*4882a593Smuzhiyun return(-EIO);
97*4882a593Smuzhiyun }
98*4882a593Smuzhiyun
99*4882a593Smuzhiyun simple_map_init(mapp);
100*4882a593Smuzhiyun
101*4882a593Smuzhiyun mtd = do_map_probe("map_" MAP_NAME, mapp);
102*4882a593Smuzhiyun if (!mtd) {
103*4882a593Smuzhiyun printk("uclinux[mtd]: failed to find a mapping?\n");
104*4882a593Smuzhiyun return(-ENXIO);
105*4882a593Smuzhiyun }
106*4882a593Smuzhiyun
107*4882a593Smuzhiyun mtd->owner = THIS_MODULE;
108*4882a593Smuzhiyun mtd->_point = uclinux_point;
109*4882a593Smuzhiyun mtd->priv = mapp;
110*4882a593Smuzhiyun
111*4882a593Smuzhiyun uclinux_ram_mtdinfo = mtd;
112*4882a593Smuzhiyun mtd_device_register(mtd, uclinux_romfs, NUM_PARTITIONS);
113*4882a593Smuzhiyun
114*4882a593Smuzhiyun return(0);
115*4882a593Smuzhiyun }
116*4882a593Smuzhiyun device_initcall(uclinux_mtd_init);
117*4882a593Smuzhiyun
118*4882a593Smuzhiyun /****************************************************************************/
119