d4fb9a3ab4dfd88bd4c7a9d456f25d7613b449cc
[linux-2.6.git] / drivers / mtd / maps / ixp2000.c
1 /*
2  * drivers/mtd/maps/ixp2000.c
3  *
4  * Mapping for the Intel XScale IXP2000 based systems
5  *
6  * Copyright (C) 2002 Intel Corp.
7  * Copyright (C) 2003-2004 MontaVista Software, Inc.
8  *
9  * Original Author: Naeem M Afzal <naeem.m.afzal@intel.com>
10  * Maintainer: Deepak Saxena <dsaxena@plexity.net>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License version 2 as
14  * published by the Free Software Foundation.
15  *
16  */
17
18 #include <linux/module.h>
19 #include <linux/types.h>
20 #include <linux/init.h>
21 #include <linux/kernel.h>
22 #include <linux/string.h>
23 #include <linux/slab.h>
24 #include <linux/ioport.h>
25 #include <linux/device.h>
26 #include <linux/platform_device.h>
27
28 #include <linux/mtd/mtd.h>
29 #include <linux/mtd/map.h>
30 #include <linux/mtd/partitions.h>
31
32 #include <asm/io.h>
33 #include <mach/hardware.h>
34 #include <asm/mach/flash.h>
35
36 #include <linux/reboot.h>
37
38 struct ixp2000_flash_info {
39         struct          mtd_info *mtd;
40         struct          map_info map;
41         struct          mtd_partition *partitions;
42         struct          resource *res;
43 };
44
45 static inline unsigned long flash_bank_setup(struct map_info *map, unsigned long ofs)
46 {
47         unsigned long (*set_bank)(unsigned long) =
48                 (unsigned long(*)(unsigned long))map->map_priv_2;
49
50         return (set_bank ? set_bank(ofs) : ofs);
51 }
52
53 #ifdef __ARMEB__
54 /*
55  * Rev A0 and A1 of IXP2400 silicon have a broken addressing unit which
56  * causes the lower address bits to be XORed with 0x11 on 8 bit accesses
57  * and XORed with 0x10 on 16 bit accesses. See the spec update, erratum 44.
58  */
59 static int erratum44_workaround = 0;
60
61 static inline unsigned long address_fix8_write(unsigned long addr)
62 {
63         if (erratum44_workaround) {
64                 return (addr ^ 3);
65         }
66         return addr;
67 }
68 #else
69
70 #define address_fix8_write(x)   (x)
71 #endif
72
73 static map_word ixp2000_flash_read8(struct map_info *map, unsigned long ofs)
74 {
75         map_word val;
76
77         val.x[0] =  *((u8 *)(map->map_priv_1 + flash_bank_setup(map, ofs)));
78         return val;
79 }
80
81 /*
82  * We can't use the standard memcpy due to the broken SlowPort
83  * address translation on rev A0 and A1 silicon and the fact that
84  * we have banked flash.
85  */
86 static void ixp2000_flash_copy_from(struct map_info *map, void *to,
87                               unsigned long from, ssize_t len)
88 {
89         from = flash_bank_setup(map, from);
90         while(len--)
91                 *(__u8 *) to++ = *(__u8 *)(map->map_priv_1 + from++);
92 }
93
94 static void ixp2000_flash_write8(struct map_info *map, map_word d, unsigned long ofs)
95 {
96         *(__u8 *) (address_fix8_write(map->map_priv_1 +
97                                       flash_bank_setup(map, ofs))) = d.x[0];
98 }
99
100 static void ixp2000_flash_copy_to(struct map_info *map, unsigned long to,
101                             const void *from, ssize_t len)
102 {
103         to = flash_bank_setup(map, to);
104         while(len--) {
105                 unsigned long tmp = address_fix8_write(map->map_priv_1 + to++);
106                 *(__u8 *)(tmp) = *(__u8 *)(from++);
107         }
108 }
109
110
111 static int ixp2000_flash_remove(struct platform_device *dev)
112 {
113         struct flash_platform_data *plat = dev->dev.platform_data;
114         struct ixp2000_flash_info *info = platform_get_drvdata(dev);
115
116         platform_set_drvdata(dev, NULL);
117
118         if(!info)
119                 return 0;
120
121         if (info->mtd) {
122                 del_mtd_partitions(info->mtd);
123                 map_destroy(info->mtd);
124         }
125         if (info->map.map_priv_1)
126                 iounmap((void *) info->map.map_priv_1);
127
128         kfree(info->partitions);
129
130         if (info->res) {
131                 release_resource(info->res);
132                 kfree(info->res);
133         }
134
135         if (plat->exit)
136                 plat->exit();
137
138         return 0;
139 }
140
141
142 static int ixp2000_flash_probe(struct platform_device *dev)
143 {
144         static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };
145         struct ixp2000_flash_data *ixp_data = dev->dev.platform_data;
146         struct flash_platform_data *plat;
147         struct ixp2000_flash_info *info;
148         unsigned long window_size;
149         int err = -1;
150
151         if (!ixp_data)
152                 return -ENODEV;
153
154         plat = ixp_data->platform_data;
155         if (!plat)
156                 return -ENODEV;
157
158         window_size = dev->resource->end - dev->resource->start + 1;
159         dev_info(&dev->dev, "Probe of IXP2000 flash(%d banks x %dMiB)\n",
160                  ixp_data->nr_banks, ((u32)window_size >> 20));
161
162         if (plat->width != 1) {
163                 dev_err(&dev->dev, "IXP2000 MTD map only supports 8-bit mode, asking for %d\n",
164                         plat->width * 8);
165                 return -EIO;
166         }
167
168         info = kmalloc(sizeof(struct ixp2000_flash_info), GFP_KERNEL);
169         if(!info) {
170                 err = -ENOMEM;
171                 goto Error;
172         }
173         memset(info, 0, sizeof(struct ixp2000_flash_info));
174
175         platform_set_drvdata(dev, info);
176
177         /*
178          * Tell the MTD layer we're not 1:1 mapped so that it does
179          * not attempt to do a direct access on us.
180          */
181         info->map.phys = NO_XIP;
182
183         info->map.size = ixp_data->nr_banks * window_size;
184         info->map.bankwidth = 1;
185
186         /*
187          * map_priv_2 is used to store a ptr to to the bank_setup routine
188          */
189         info->map.map_priv_2 = (unsigned long) ixp_data->bank_setup;
190
191         info->map.name = dev_name(&dev->dev);
192         info->map.read = ixp2000_flash_read8;
193         info->map.write = ixp2000_flash_write8;
194         info->map.copy_from = ixp2000_flash_copy_from;
195         info->map.copy_to = ixp2000_flash_copy_to;
196
197         info->res = request_mem_region(dev->resource->start,
198                         dev->resource->end - dev->resource->start + 1,
199                         dev_name(&dev->dev));
200         if (!info->res) {
201                 dev_err(&dev->dev, "Could not reserve memory region\n");
202                 err = -ENOMEM;
203                 goto Error;
204         }
205
206         info->map.map_priv_1 = (unsigned long) ioremap(dev->resource->start,
207                                 dev->resource->end - dev->resource->start + 1);
208         if (!info->map.map_priv_1) {
209                 dev_err(&dev->dev, "Failed to ioremap flash region\n");
210                 err = -EIO;
211                 goto Error;
212         }
213
214 #if defined(__ARMEB__)
215         /*
216          * Enable erratum 44 workaround for NPUs with broken slowport
217          */
218
219         erratum44_workaround = ixp2000_has_broken_slowport();
220         dev_info(&dev->dev, "Erratum 44 workaround %s\n",
221                erratum44_workaround ? "enabled" : "disabled");
222 #endif
223
224         info->mtd = do_map_probe(plat->map_name, &info->map);
225         if (!info->mtd) {
226                 dev_err(&dev->dev, "map_probe failed\n");
227                 err = -ENXIO;
228                 goto Error;
229         }
230         info->mtd->owner = THIS_MODULE;
231
232         err = parse_mtd_partitions(info->mtd, probes, &info->partitions, 0);
233         if (err > 0) {
234                 err = add_mtd_partitions(info->mtd, info->partitions, err);
235                 if(err)
236                         dev_err(&dev->dev, "Could not parse partitions\n");
237         }
238
239         if (err)
240                 goto Error;
241
242         return 0;
243
244 Error:
245         ixp2000_flash_remove(dev);
246         return err;
247 }
248
249 static struct platform_driver ixp2000_flash_driver = {
250         .probe          = ixp2000_flash_probe,
251         .remove         = ixp2000_flash_remove,
252         .driver         = {
253                 .name   = "IXP2000-Flash",
254                 .owner  = THIS_MODULE,
255         },
256 };
257
258 static int __init ixp2000_flash_init(void)
259 {
260         return platform_driver_register(&ixp2000_flash_driver);
261 }
262
263 static void __exit ixp2000_flash_exit(void)
264 {
265         platform_driver_unregister(&ixp2000_flash_driver);
266 }
267
268 module_init(ixp2000_flash_init);
269 module_exit(ixp2000_flash_exit);
270 MODULE_LICENSE("GPL");
271 MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
272 MODULE_ALIAS("platform:IXP2000-Flash");