summaryrefslogtreecommitdiff
path: root/drivers/mtd/maps/sa1100-flash.c
blob: d3d4e987c163e23cd5e72acd1a1a2368ff10b0c9 (plain)
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
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Flash memory access on SA11x0 based devices
 *
 * (C) 2000 Nicolas Pitre <nico@fluxnic.net>
 */
#include <linux/module.h>
#include <linux/types.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/io.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/concat.h>

#include <mach/hardware.h>
#include <linux/sizes.h>
#include <asm/mach/flash.h>

struct sa_subdev_info {
	char name[16];
	struct map_info map;
	struct mtd_info *mtd;
	struct flash_platform_data *plat;
};

struct sa_info {
	struct mtd_info		*mtd;
	int			num_subdev;
	struct sa_subdev_info	subdev[];
};

static DEFINE_SPINLOCK(sa1100_vpp_lock);
static int sa1100_vpp_refcnt;
static void sa1100_set_vpp(struct map_info *map, int on)
{
	struct sa_subdev_info *subdev = container_of(map, struct sa_subdev_info, map);
	unsigned long flags;

	spin_lock_irqsave(&sa1100_vpp_lock, flags);
	if (on) {
		if (++sa1100_vpp_refcnt == 1)   /* first nested 'on' */
			subdev->plat->set_vpp(1);
	} else {
		if (--sa1100_vpp_refcnt == 0)   /* last nested 'off' */
			subdev->plat->set_vpp(0);
	}
	spin_unlock_irqrestore(&sa1100_vpp_lock, flags);
}

static void sa1100_destroy_subdev(struct sa_subdev_info *subdev)
{
	if (subdev->mtd)
		map_destroy(subdev->mtd);
	if (subdev->map.virt)
		iounmap(subdev->map.virt);
	release_mem_region(subdev->map.phys, subdev->map.size);
}

static int sa1100_probe_subdev(struct sa_subdev_info *subdev, struct resource *res)
{
	unsigned long phys;
	unsigned int size;
	int ret;

	phys = res->start;
	size = res->end - phys + 1;

	/*
	 * Retrieve the bankwidth from the MSC registers.
	 * We currently only implement CS0 and CS1 here.
	 */
	switch (phys) {
	default:
		printk(KERN_WARNING "SA1100 flash: unknown base address "
		       "0x%08lx, assuming CS0\n", phys);
		fallthrough;
	case SA1100_CS0_PHYS:
		subdev->map.bankwidth = (MSC0 & MSC_RBW) ? 2 : 4;
		break;

	case SA1100_CS1_PHYS:
		subdev->map.bankwidth = ((MSC0 >> 16) & MSC_RBW) ? 2 : 4;
		break;
	}

	if (!request_mem_region(phys, size, subdev->name)) {
		ret = -EBUSY;
		goto out;
	}

	if (subdev->plat->set_vpp)
		subdev->map.set_vpp = sa1100_set_vpp;

	subdev->map.phys = phys;
	subdev->map.size = size;
	subdev->map.virt = ioremap(phys, size);
	if (!subdev->map.virt) {
		ret = -ENOMEM;
		goto err;
	}

	simple_map_init(&subdev->map);

	/*
	 * Now let's probe for the actual flash.  Do it here since
	 * specific machine settings might have been set above.
	 */
	subdev->mtd = do_map_probe(subdev->plat->map_name, &subdev->map);
	if (subdev->mtd == NULL) {
		ret = -ENXIO;
		goto err;
	}

	printk(KERN_INFO "SA1100 flash: CFI device at 0x%08lx, %uMiB, %d-bit\n",
		phys, (unsigned)(subdev->mtd->size >> 20),
		subdev->map.bankwidth * 8);

	return 0;

 err:
	sa1100_destroy_subdev(subdev);
 out:
	return ret;
}

static void sa1100_destroy(struct sa_info *info, struct flash_platform_data *plat)
{
	int i;

	if (info->mtd) {
		mtd_device_unregister(info->mtd);
		if (info->mtd != info->subdev[0].mtd)
			mtd_concat_destroy(info->mtd);
	}

	for (i = info->num_subdev - 1; i >= 0; i--)
		sa1100_destroy_subdev(&info->subdev[i]);
	kfree(info);

	if (plat->exit)
		plat->exit();
}

static struct sa_info *sa1100_setup_mtd(struct platform_device *pdev,
					struct flash_platform_data *plat)
{
	struct sa_info *info;
	int nr, size, i, ret = 0;

	/*
	 * Count number of devices.
	 */
	for (nr = 0; ; nr++)
		if (!platform_get_resource(pdev, IORESOURCE_MEM, nr))
			break;

	if (nr == 0) {
		ret = -ENODEV;
		goto out;
	}

	size = sizeof(struct sa_info) + sizeof(struct sa_subdev_info) * nr;

	/*
	 * Allocate the map_info structs in one go.
	 */
	info = kzalloc(size, GFP_KERNEL);
	if (!info) {
		ret = -ENOMEM;
		goto out;
	}

	if (plat->init) {
		ret = plat->init();
		if (ret)
			goto err;
	}

	/*
	 * Claim and then map the memory regions.
	 */
	for (i = 0; i < nr; i++) {
		struct sa_subdev_info *subdev = &info->subdev[i];
		struct resource *res;

		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
		if (!res)
			break;

		subdev->map.name = subdev->name;
		sprintf(subdev->name, "%s-%d", plat->name, i);
		subdev->plat = plat;

		ret = sa1100_probe_subdev(subdev, res);
		if (ret)
			break;
	}

	info->num_subdev = i;

	/*
	 * ENXIO is special.  It means we didn't find a chip when we probed.
	 */
	if (ret != 0 && !(ret == -ENXIO && info->num_subdev > 0))
		goto err;

	/*
	 * If we found one device, don't bother with concat support.  If
	 * we found multiple devices, use concat if we have it available,
	 * otherwise fail.  Either way, it'll be called "sa1100".
	 */
	if (info->num_subdev == 1) {
		strcpy(info->subdev[0].name, plat->name);
		info->mtd = info->subdev[0].mtd;
		ret = 0;
	} else if (info->num_subdev > 1) {
		struct mtd_info **cdev;

		cdev = kmalloc_array(nr, sizeof(*cdev), GFP_KERNEL);
		if (!cdev) {
			ret = -ENOMEM;
			goto err;
		}

		/*
		 * We detected multiple devices.  Concatenate them together.
		 */
		for (i = 0; i < info->num_subdev; i++)
			cdev[i] = info->subdev[i].mtd;

		info->mtd = mtd_concat_create(cdev, info->num_subdev,
					      plat->name);
		kfree(cdev);
		if (info->mtd == NULL) {
			ret = -ENXIO;
			goto err;
		}
	}
	info->mtd->dev.parent = &pdev->dev;

	if (ret == 0)
		return info;

 err:
	sa1100_destroy(info, plat);
 out:
	return ERR_PTR(ret);
}

static const char * const part_probes[] = { "cmdlinepart", "RedBoot", NULL };

static int sa1100_mtd_probe(struct platform_device *pdev)
{
	struct flash_platform_data *plat = dev_get_platdata(&pdev->dev);
	struct sa_info *info;
	int err;

	if (!plat)
		return -ENODEV;

	info = sa1100_setup_mtd(pdev, plat);
	if (IS_ERR(info)) {
		err = PTR_ERR(info);
		goto out;
	}

	/*
	 * Partition selection stuff.
	 */
	mtd_device_parse_register(info->mtd, part_probes, NULL, plat->parts,
				  plat->nr_parts);

	platform_set_drvdata(pdev, info);
	err = 0;

 out:
	return err;
}

static int sa1100_mtd_remove(struct platform_device *pdev)
{
	struct sa_info *info = platform_get_drvdata(pdev);
	struct flash_platform_data *plat = dev_get_platdata(&pdev->dev);

	sa1100_destroy(info, plat);

	return 0;
}

static struct platform_driver sa1100_mtd_driver = {
	.probe		= sa1100_mtd_probe,
	.remove		= sa1100_mtd_remove,
	.driver		= {
		.name	= "sa1100-mtd",
	},
};

module_platform_driver(sa1100_mtd_driver);

MODULE_AUTHOR("Nicolas Pitre");
MODULE_DESCRIPTION("SA1100 CFI map driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:sa1100-mtd");