summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/maps/ixp2000.c
blob: d76880d91bdbbc1317d215962595f082bd80caa2 (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
/*
 * drivers/mtd/maps/ixp2000.c
 *
 * Mapping for the Intel XScale IXP2000 based systems
 *
 * Copyright (C) 2002 Intel Corp.
 * Copyright (C) 2003-2004 MontaVista Software, Inc.
 *
 * Original Author: Naeem M Afzal <naeem.m.afzal@intel.com>
 * Maintainer: Deepak Saxena <dsaxena@plexity.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/device.h>
#include <linux/platform_device.h>

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

#include <asm/io.h>
#include <mach/hardware.h>
#include <asm/mach/flash.h>

#include <linux/reboot.h>

struct ixp2000_flash_info {
	struct		mtd_info *mtd;
	struct		map_info map;
	struct		mtd_partition *partitions;
	struct		resource *res;
};

static inline unsigned long flash_bank_setup(struct map_info *map, unsigned long ofs)
{
	unsigned long (*set_bank)(unsigned long) =
		(unsigned long(*)(unsigned long))map->map_priv_2;

	return (set_bank ? set_bank(ofs) : ofs);
}

#ifdef __ARMEB__
/*
 * Rev A0 and A1 of IXP2400 silicon have a broken addressing unit which
 * causes the lower address bits to be XORed with 0x11 on 8 bit accesses
 * and XORed with 0x10 on 16 bit accesses. See the spec update, erratum 44.
 */
static int erratum44_workaround = 0;

static inline unsigned long address_fix8_write(unsigned long addr)
{
	if (erratum44_workaround) {
		return (addr ^ 3);
	}
	return addr;
}
#else

#define address_fix8_write(x)	(x)
#endif

static map_word ixp2000_flash_read8(struct map_info *map, unsigned long ofs)
{
	map_word val;

	val.x[0] =  *((u8 *)(map->map_priv_1 + flash_bank_setup(map, ofs)));
	return val;
}

/*
 * We can't use the standard memcpy due to the broken SlowPort
 * address translation on rev A0 and A1 silicon and the fact that
 * we have banked flash.
 */
static void ixp2000_flash_copy_from(struct map_info *map, void *to,
			      unsigned long from, ssize_t len)
{
	from = flash_bank_setup(map, from);
	while(len--)
		*(__u8 *) to++ = *(__u8 *)(map->map_priv_1 + from++);
}

static void ixp2000_flash_write8(struct map_info *map, map_word d, unsigned long ofs)
{
	*(__u8 *) (address_fix8_write(map->map_priv_1 +
				      flash_bank_setup(map, ofs))) = d.x[0];
}

static void ixp2000_flash_copy_to(struct map_info *map, unsigned long to,
			    const void *from, ssize_t len)
{
	to = flash_bank_setup(map, to);
	while(len--) {
		unsigned long tmp = address_fix8_write(map->map_priv_1 + to++);
		*(__u8 *)(tmp) = *(__u8 *)(from++);
	}
}


static int ixp2000_flash_remove(struct platform_device *dev)
{
	struct flash_platform_data *plat = dev->dev.platform_data;
	struct ixp2000_flash_info *info = platform_get_drvdata(dev);

	platform_set_drvdata(dev, NULL);

	if(!info)
		return 0;

	if (info->mtd) {
		del_mtd_partitions(info->mtd);
		map_destroy(info->mtd);
	}
	if (info->map.map_priv_1)
		iounmap((void *) info->map.map_priv_1);

	kfree(info->partitions);

	if (info->res) {
		release_resource(info->res);
		kfree(info->res);
	}

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

	return 0;
}


static int ixp2000_flash_probe(struct platform_device *dev)
{
	static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };
	struct ixp2000_flash_data *ixp_data = dev->dev.platform_data;
	struct flash_platform_data *plat;
	struct ixp2000_flash_info *info;
	unsigned long window_size;
	int err = -1;

	if (!ixp_data)
		return -ENODEV;

	plat = ixp_data->platform_data;
	if (!plat)
		return -ENODEV;

	window_size = dev->resource->end - dev->resource->start + 1;
	dev_info(&dev->dev, "Probe of IXP2000 flash(%d banks x %dMiB)\n",
		 ixp_data->nr_banks, ((u32)window_size >> 20));

	if (plat->width != 1) {
		dev_err(&dev->dev, "IXP2000 MTD map only supports 8-bit mode, asking for %d\n",
			plat->width * 8);
		return -EIO;
	}

	info = kmalloc(sizeof(struct ixp2000_flash_info), GFP_KERNEL);
	if(!info) {
		err = -ENOMEM;
		goto Error;
	}
	memzero(info, sizeof(struct ixp2000_flash_info));

	platform_set_drvdata(dev, info);

	/*
	 * Tell the MTD layer we're not 1:1 mapped so that it does
	 * not attempt to do a direct access on us.
	 */
	info->map.phys = NO_XIP;

	info->map.size = ixp_data->nr_banks * window_size;
	info->map.bankwidth = 1;

	/*
 	 * map_priv_2 is used to store a ptr to to the bank_setup routine
 	 */
	info->map.map_priv_2 = (unsigned long) ixp_data->bank_setup;

	info->map.name = dev_name(&dev->dev);
	info->map.read = ixp2000_flash_read8;
	info->map.write = ixp2000_flash_write8;
	info->map.copy_from = ixp2000_flash_copy_from;
	info->map.copy_to = ixp2000_flash_copy_to;

	info->res = request_mem_region(dev->resource->start,
			dev->resource->end - dev->resource->start + 1,
			dev_name(&dev->dev));
	if (!info->res) {
		dev_err(&dev->dev, "Could not reserve memory region\n");
		err = -ENOMEM;
		goto Error;
	}

	info->map.map_priv_1 = (unsigned long) ioremap(dev->resource->start,
			    	dev->resource->end - dev->resource->start + 1);
	if (!info->map.map_priv_1) {
		dev_err(&dev->dev, "Failed to ioremap flash region\n");
		err = -EIO;
		goto Error;
	}

#if defined(__ARMEB__)
	/*
	 * Enable erratum 44 workaround for NPUs with broken slowport
	 */

	erratum44_workaround = ixp2000_has_broken_slowport();
	dev_info(&dev->dev, "Erratum 44 workaround %s\n",
	       erratum44_workaround ? "enabled" : "disabled");
#endif

	info->mtd = do_map_probe(plat->map_name, &info->map);
	if (!info->mtd) {
		dev_err(&dev->dev, "map_probe failed\n");
		err = -ENXIO;
		goto Error;
	}
	info->mtd->owner = THIS_MODULE;

	err = parse_mtd_partitions(info->mtd, probes, &info->partitions, 0);
	if (err > 0) {
		err = add_mtd_partitions(info->mtd, info->partitions, err);
		if(err)
			dev_err(&dev->dev, "Could not parse partitions\n");
	}

	if (err)
		goto Error;

	return 0;

Error:
	ixp2000_flash_remove(dev);
	return err;
}

static struct platform_driver ixp2000_flash_driver = {
	.probe		= ixp2000_flash_probe,
	.remove		= ixp2000_flash_remove,
	.driver		= {
		.name	= "IXP2000-Flash",
		.owner	= THIS_MODULE,
	},
};

static int __init ixp2000_flash_init(void)
{
	return platform_driver_register(&ixp2000_flash_driver);
}

static void __exit ixp2000_flash_exit(void)
{
	platform_driver_unregister(&ixp2000_flash_driver);
}

module_init(ixp2000_flash_init);
module_exit(ixp2000_flash_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
MODULE_ALIAS("platform:IXP2000-Flash");