Linux-2.6.12-rc2
[linux-2.6] / drivers / mtd / maps / tsunami_flash.c
1 /*
2  * tsunami_flash.c
3  *
4  * flash chip on alpha ds10...
5  * $Id: tsunami_flash.c,v 1.9 2004/07/14 09:52:55 dwmw2 Exp $
6  */
7 #include <asm/io.h>
8 #include <asm/core_tsunami.h>
9 #include <linux/init.h>
10 #include <linux/mtd/map.h>
11 #include <linux/mtd/mtd.h>
12
13 #define FLASH_ENABLE_PORT 0x00C00001
14 #define FLASH_ENABLE_BYTE 0x01
15 #define FLASH_DISABLE_BYTE 0x00
16
17 #define MAX_TIG_FLASH_SIZE (12*1024*1024)
18 static inline map_word tsunami_flash_read8(struct map_info *map, unsigned long offset)
19 {
20         map_word val;
21         val.x[0] = tsunami_tig_readb(offset);
22         return val;
23 }
24
25 static void tsunami_flash_write8(struct map_info *map, map_word value, unsigned long offset)
26 {
27         tsunami_tig_writeb(value.x[0], offset);
28 }
29
30 static void tsunami_flash_copy_from(
31         struct map_info *map, void *addr, unsigned long offset, ssize_t len)
32 {
33         unsigned char *dest;
34         dest = addr;
35         while(len && (offset < MAX_TIG_FLASH_SIZE)) {
36                 *dest = tsunami_tig_readb(offset);
37                 offset++;
38                 dest++;
39                 len--;
40         }
41 }
42
43 static void tsunami_flash_copy_to(
44         struct map_info *map, unsigned long offset, 
45         const void *addr, ssize_t len)
46 {
47         const unsigned char *src;
48         src = addr;
49         while(len && (offset < MAX_TIG_FLASH_SIZE)) {
50                 tsunami_tig_writeb(*src, offset);
51                 offset++;
52                 src++;
53                 len--;
54         }
55 }
56
57 /*
58  * Deliberately don't provide operations wider than 8 bits.  I don't
59  * have then and it scares me to think how you could mess up if
60  * you tried to use them.   Buswidth is correctly so I'm safe.
61  */
62 static struct map_info tsunami_flash_map = {
63         .name = "flash chip on the Tsunami TIG bus",
64         .size = MAX_TIG_FLASH_SIZE,
65         .phys = NO_XIP;
66         .bankwidth = 1,
67         .read = tsunami_flash_read8,
68         .copy_from = tsunami_flash_copy_from,
69         .write = tsunami_flash_write8,
70         .copy_to = tsunami_flash_copy_to,
71 };
72
73 static struct mtd_info *tsunami_flash_mtd;
74
75 static void __exit  cleanup_tsunami_flash(void)
76 {
77         struct mtd_info *mtd;
78         mtd = tsunami_flash_mtd;
79         if (mtd) {
80                 del_mtd_device(mtd);
81                 map_destroy(mtd);
82         }
83         tsunami_flash_mtd = 0;
84 }
85
86
87 static int __init init_tsunami_flash(void)
88 {
89         static const char *rom_probe_types[] = { "cfi_probe", "jedec_probe", "map_rom", NULL };
90         char **type;
91
92         tsunami_tig_writeb(FLASH_ENABLE_BYTE, FLASH_ENABLE_PORT);
93         
94         tsunami_flash_mtd = 0;
95         type = rom_probe_types;
96         for(; !tsunami_flash_mtd && *type; type++) {
97                 tsunami_flash_mtd = do_map_probe(*type, &tsunami_flash_map);
98         }
99         if (tsunami_flash_mtd) {
100                 tsunami_flash_mtd->owner = THIS_MODULE;
101                 add_mtd_device(tsunami_flash_mtd);
102                 return 0;
103         }
104         return -ENXIO;
105 }
106
107 module_init(init_tsunami_flash);
108 module_exit(cleanup_tsunami_flash);