aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/mtd/maps/bfin-async-flash.c
blob: a7c808b577d376a5f99edc98adcf5dd49cc2cba0 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
/*
 * drivers/mtd/maps/bfin-async-flash.c
 *
 * Handle the case where flash memory and ethernet mac/phy are
 * mapped onto the same async bank.  The BF533-STAMP does this
 * for example.  All board-specific configuration goes in your
 * board resources file.
 *
 * Copyright 2000 Nicolas Pitre <nico@fluxnic.net>
 * Copyright 2005-2008 Analog Devices Inc.
 *
 * Enter bugs at http://blackfin.uclinux.org/
 *
 * Licensed under the GPL-2 or later.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/physmap.h>
#include <linux/platform_device.h>
#include <linux/types.h>

#include <asm/blackfin.h>
#include <linux/gpio.h>
#include <linux/io.h>
#include <asm/unaligned.h>

#define pr_devinit(fmt, args...) ({ static const __devinitconst char __fmt[] = fmt; printk(__fmt, ## args); })

#define DRIVER_NAME "bfin-async-flash"

struct async_state {
	struct mtd_info *mtd;
	struct map_info map;
	int enet_flash_pin;
	uint32_t flash_ambctl0, flash_ambctl1;
	uint32_t save_ambctl0, save_ambctl1;
	unsigned long irq_flags;
#ifdef CONFIG_MTD_PARTITIONS
	struct mtd_partition *parts;
#endif
};

static void switch_to_flash(struct async_state *state)
{
	local_irq_save(state->irq_flags);

	gpio_set_value(state->enet_flash_pin, 0);

	state->save_ambctl0 = bfin_read_EBIU_AMBCTL0();
	state->save_ambctl1 = bfin_read_EBIU_AMBCTL1();
	bfin_write_EBIU_AMBCTL0(state->flash_ambctl0);
	bfin_write_EBIU_AMBCTL1(state->flash_ambctl1);
	SSYNC();
}

static void switch_back(struct async_state *state)
{
	bfin_write_EBIU_AMBCTL0(state->save_ambctl0);
	bfin_write_EBIU_AMBCTL1(state->save_ambctl1);
	SSYNC();

	gpio_set_value(state->enet_flash_pin, 1);

	local_irq_restore(state->irq_flags);
}

static map_word bfin_read(struct map_info *map, unsigned long ofs)
{
	struct async_state *state = (struct async_state *)map->map_priv_1;
	uint16_t word;
	map_word test;

	switch_to_flash(state);

	word = readw(map->virt + ofs);

	switch_back(state);

	test.x[0] = word;
	return test;
}

static void bfin_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
{
	struct async_state *state = (struct async_state *)map->map_priv_1;

	switch_to_flash(state);

	memcpy(to, map->virt + from, len);

	switch_back(state);
}

static void bfin_write(struct map_info *map, map_word d1, unsigned long ofs)
{
	struct async_state *state = (struct async_state *)map->map_priv_1;
	uint16_t d;

	d = d1.x[0];

	switch_to_flash(state);

	writew(d, map->virt + ofs);
	SSYNC();

	switch_back(state);
}

static void bfin_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
{
	struct async_state *state = (struct async_state *)map->map_priv_1;

	switch_to_flash(state);

	memcpy(map->virt + to, from, len);
	SSYNC();

	switch_back(state);
}

#ifdef CONFIG_MTD_PARTITIONS
static const char *part_probe_types[] = { "cmdlinepart", "RedBoot", NULL };
#endif

static int __devinit bfin_flash_probe(struct platform_device *pdev)
{
	int ret;
	struct physmap_flash_data *pdata = pdev->dev.platform_data;
	struct resource *memory = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	struct resource *flash_ambctl = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	struct async_state *state;

	state = kzalloc(sizeof(*state), GFP_KERNEL);
	if (!state)
		return -ENOMEM;

	state->map.name       = DRIVER_NAME;
	state->map.read       = bfin_read;
	state->map.copy_from  = bfin_copy_from;
	state->map.write      = bfin_write;
	state->map.copy_to    = bfin_copy_to;
	state->map.bankwidth  = pdata->width;
	state->map.size       = memory->end - memory->start + 1;
	state->map.virt       = (void __iomem *)memory->start;
	state->map.phys       = memory->start;
	state->map.map_priv_1 = (unsigned long)state;
	state->enet_flash_pin = platform_get_irq(pdev, 0);
	state->flash_ambctl0  = flash_ambctl->start;
	state->flash_ambctl1  = flash_ambctl->end;

	if (gpio_request(state->enet_flash_pin, DRIVER_NAME)) {
		pr_devinit(KERN_ERR DRIVER_NAME ": Failed to request gpio %d\n", state->enet_flash_pin);
		kfree(state);
		return -EBUSY;
	}
	gpio_direction_output(state->enet_flash_pin, 1);

	pr_devinit(KERN_NOTICE DRIVER_NAME ": probing %d-bit flash bus\n", state->map.bankwidth * 8);
	state->mtd = do_map_probe(memory->name, &state->map);
	if (!state->mtd) {
		gpio_free(state->enet_flash_pin);
		kfree(state);
		return -ENXIO;
	}

#ifdef CONFIG_MTD_PARTITIONS
	ret = parse_mtd_partitions(state->mtd, part_probe_types, &pdata->parts, 0);
	if (ret > 0) {
		pr_devinit(KERN_NOTICE DRIVER_NAME ": Using commandline partition definition\n");
		add_mtd_partitions(state->mtd, pdata->parts, ret);
		state->parts = pdata->parts;

	} else if (pdata->nr_parts) {
		pr_devinit(KERN_NOTICE DRIVER_NAME ": Using board partition definition\n");
		add_mtd_partitions(state->mtd, pdata->parts, pdata->nr_parts);

	} else
#endif
	{
		pr_devinit(KERN_NOTICE DRIVER_NAME ": no partition info available, registering whole flash at once\n");
		add_mtd_device(state->mtd);
	}

	platform_set_drvdata(pdev, state);

	return 0;
}

static int __devexit bfin_flash_remove(struct platform_device *pdev)
{
	struct async_state *state = platform_get_drvdata(pdev);
	gpio_free(state->enet_flash_pin);
#ifdef CONFIG_MTD_PARTITIONS
	del_mtd_partitions(state->mtd);
	kfree(state->parts);
#endif
	map_destroy(state->mtd);
	kfree(state);
	return 0;
}

static struct platform_driver bfin_flash_driver = {
	.probe		= bfin_flash_probe,
	.remove		= __devexit_p(bfin_flash_remove),
	.driver		= {
		.name	= DRIVER_NAME,
	},
};

static int __init bfin_flash_init(void)
{
	return platform_driver_register(&bfin_flash_driver);
}
module_init(bfin_flash_init);

static void __exit bfin_flash_exit(void)
{
	platform_driver_unregister(&bfin_flash_driver);
}
module_exit(bfin_flash_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MTD map driver for Blackfins with flash/ethernet on same async bank");