1/*
2 * tsunami_flash.c
3 *
4 * flash chip on alpha ds10...
5 */
6#include <asm/io.h>
7#include <asm/core_tsunami.h>
8#include <linux/init.h>
9#include <linux/mtd/map.h>
10#include <linux/mtd/mtd.h>
11
12#define FLASH_ENABLE_PORT 0x00C00001
13#define FLASH_ENABLE_BYTE 0x01
14#define FLASH_DISABLE_BYTE 0x00
15
16#define MAX_TIG_FLASH_SIZE (12*1024*1024)
17static inline map_word tsunami_flash_read8(struct map_info *map, unsigned long offset)
18{
19	map_word val;
20	val.x[0] = tsunami_tig_readb(offset);
21	return val;
22}
23
24static void tsunami_flash_write8(struct map_info *map, map_word value, unsigned long offset)
25{
26	tsunami_tig_writeb(value.x[0], offset);
27}
28
29static void tsunami_flash_copy_from(
30	struct map_info *map, void *addr, unsigned long offset, ssize_t len)
31{
32	unsigned char *dest;
33	dest = addr;
34	while(len && (offset < MAX_TIG_FLASH_SIZE)) {
35		*dest = tsunami_tig_readb(offset);
36		offset++;
37		dest++;
38		len--;
39	}
40}
41
42static void tsunami_flash_copy_to(
43	struct map_info *map, unsigned long offset,
44	const void *addr, ssize_t len)
45{
46	const unsigned char *src;
47	src = addr;
48	while(len && (offset < MAX_TIG_FLASH_SIZE)) {
49		tsunami_tig_writeb(*src, offset);
50		offset++;
51		src++;
52		len--;
53	}
54}
55
56/*
57 * Deliberately don't provide operations wider than 8 bits.  I don't
58 * have then and it scares me to think how you could mess up if
59 * you tried to use them.   Buswidth is correctly so I'm safe.
60 */
61static struct map_info tsunami_flash_map = {
62	.name = "flash chip on the Tsunami TIG bus",
63	.size = MAX_TIG_FLASH_SIZE,
64	.phys = NO_XIP,
65	.bankwidth = 1,
66	.read = tsunami_flash_read8,
67	.copy_from = tsunami_flash_copy_from,
68	.write = tsunami_flash_write8,
69	.copy_to = tsunami_flash_copy_to,
70};
71
72static struct mtd_info *tsunami_flash_mtd;
73
74static void __exit  cleanup_tsunami_flash(void)
75{
76	struct mtd_info *mtd;
77	mtd = tsunami_flash_mtd;
78	if (mtd) {
79		mtd_device_unregister(mtd);
80		map_destroy(mtd);
81	}
82	tsunami_flash_mtd = 0;
83}
84
85static const char * const rom_probe_types[] = {
86	"cfi_probe", "jedec_probe", "map_rom", NULL };
87
88static int __init init_tsunami_flash(void)
89{
90	const char * const *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		mtd_device_register(tsunami_flash_mtd, NULL, 0);
102		return 0;
103	}
104	return -ENXIO;
105}
106
107module_init(init_tsunami_flash);
108module_exit(cleanup_tsunami_flash);
109