Merge rsync://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / drivers / mtd / maps / ixp2000.c
1 /*
2  * $Id: ixp2000.c,v 1.9 2005/11/07 11:14:27 gleixner Exp $
3  *
4  * drivers/mtd/maps/ixp2000.c
5  *
6  * Mapping for the Intel XScale IXP2000 based systems
7  *
8  * Copyright (C) 2002 Intel Corp.
9  * Copyright (C) 2003-2004 MontaVista Software, Inc.
10  *
11  * Original Author: Naeem M Afzal <naeem.m.afzal@intel.com>
12  * Maintainer: Deepak Saxena <dsaxena@plexity.net>
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License version 2 as
16  * published by the Free Software Foundation.
17  *
18  */
19
20 #include <linux/module.h>
21 #include <linux/types.h>
22 #include <linux/init.h>
23 #include <linux/kernel.h>
24 #include <linux/string.h>
25 #include <linux/slab.h>
26 #include <linux/ioport.h>
27 #include <linux/device.h>
28 #include <linux/platform_device.h>
29
30 #include <linux/mtd/mtd.h>
31 #include <linux/mtd/map.h>
32 #include <linux/mtd/partitions.h>
33
34 #include <asm/io.h>
35 #include <asm/hardware.h>
36 #include <asm/mach/flash.h>
37
38 #include <linux/reboot.h>
39
40 struct ixp2000_flash_info {
41         struct          mtd_info *mtd;
42         struct          map_info map;
43         struct          mtd_partition *partitions;
44         struct          resource *res;
45 };
46
47 static inline unsigned long flash_bank_setup(struct map_info *map, unsigned long ofs)
48 {
49         unsigned long (*set_bank)(unsigned long) =
50                 (unsigned long(*)(unsigned long))map->map_priv_2;
51
52         return (set_bank ? set_bank(ofs) : ofs);
53 }
54
55 #ifdef __ARMEB__
56 /*
57  * Rev A0 and A1 of IXP2400 silicon have a broken addressing unit which
58  * causes the lower address bits to be XORed with 0x11 on 8 bit accesses
59  * and XORed with 0x10 on 16 bit accesses. See the spec update, erratum 44.
60  */
61 static int erratum44_workaround = 0;
62
63 static inline unsigned long address_fix8_write(unsigned long addr)
64 {
65         if (erratum44_workaround) {
66                 return (addr ^ 3);
67         }
68         return addr;
69 }
70 #else
71
72 #define address_fix8_write(x)   (x)
73 #endif
74
75 static map_word ixp2000_flash_read8(struct map_info *map, unsigned long ofs)
76 {
77         map_word val;
78
79         val.x[0] =  *((u8 *)(map->map_priv_1 + flash_bank_setup(map, ofs)));
80         return val;
81 }
82
83 /*
84  * We can't use the standard memcpy due to the broken SlowPort
85  * address translation on rev A0 and A1 silicon and the fact that
86  * we have banked flash.
87  */
88 static void ixp2000_flash_copy_from(struct map_info *map, void *to,
89                               unsigned long from, ssize_t len)
90 {
91         from = flash_bank_setup(map, from);
92         while(len--)
93                 *(__u8 *) to++ = *(__u8 *)(map->map_priv_1 + from++);
94 }
95
96 static void ixp2000_flash_write8(struct map_info *map, map_word d, unsigned long ofs)
97 {
98         *(__u8 *) (address_fix8_write(map->map_priv_1 +
99                                       flash_bank_setup(map, ofs))) = d.x[0];
100 }
101
102 static void ixp2000_flash_copy_to(struct map_info *map, unsigned long to,
103                             const void *from, ssize_t len)
104 {
105         to = flash_bank_setup(map, to);
106         while(len--) {
107                 unsigned long tmp = address_fix8_write(map->map_priv_1 + to++);
108                 *(__u8 *)(tmp) = *(__u8 *)(from++);
109         }
110 }
111
112
113 static int ixp2000_flash_remove(struct platform_device *dev)
114 {
115         struct flash_platform_data *plat = dev->dev.platform_data;
116         struct ixp2000_flash_info *info = platform_get_drvdata(dev);
117
118         platform_set_drvdata(dev, NULL);
119
120         if(!info)
121                 return 0;
122
123         if (info->mtd) {
124                 del_mtd_partitions(info->mtd);
125                 map_destroy(info->mtd);
126         }
127         if (info->map.map_priv_1)
128                 iounmap((void *) info->map.map_priv_1);
129
130         kfree(info->partitions);
131
132         if (info->res) {
133                 release_resource(info->res);
134                 kfree(info->res);
135         }
136
137         if (plat->exit)
138                 plat->exit();
139
140         return 0;
141 }
142
143
144 static int ixp2000_flash_probe(struct platform_device *dev)
145 {
146         static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };
147         struct ixp2000_flash_data *ixp_data = dev->dev.platform_data;
148         struct flash_platform_data *plat;
149         struct ixp2000_flash_info *info;
150         unsigned long window_size;
151         int err = -1;
152
153         if (!ixp_data)
154                 return -ENODEV;
155
156         plat = ixp_data->platform_data;
157         if (!plat)
158                 return -ENODEV;
159
160         window_size = dev->resource->end - dev->resource->start + 1;
161         dev_info(&dev->dev, "Probe of IXP2000 flash(%d banks x %dMiB)\n",
162                  ixp_data->nr_banks, ((u32)window_size >> 20));
163
164         if (plat->width != 1) {
165                 dev_err(&dev->dev, "IXP2000 MTD map only supports 8-bit mode, asking for %d\n",
166                         plat->width * 8);
167                 return -EIO;
168         }
169
170         info = kmalloc(sizeof(struct ixp2000_flash_info), GFP_KERNEL);
171         if(!info) {
172                 err = -ENOMEM;
173                 goto Error;
174         }
175         memzero(info, sizeof(struct ixp2000_flash_info));
176
177         platform_set_drvdata(dev, info);
178
179         /*
180          * Tell the MTD layer we're not 1:1 mapped so that it does
181          * not attempt to do a direct access on us.
182          */
183         info->map.phys = NO_XIP;
184
185         info->map.size = ixp_data->nr_banks * window_size;
186         info->map.bankwidth = 1;
187
188         /*
189          * map_priv_2 is used to store a ptr to to the bank_setup routine
190          */
191         info->map.map_priv_2 = (unsigned long) ixp_data->bank_setup;
192
193         info->map.name = dev->dev.bus_id;
194         info->map.read = ixp2000_flash_read8;
195         info->map.write = ixp2000_flash_write8;
196         info->map.copy_from = ixp2000_flash_copy_from;
197         info->map.copy_to = ixp2000_flash_copy_to;
198
199         info->res = request_mem_region(dev->resource->start,
200                         dev->resource->end - dev->resource->start + 1,
201                         dev->dev.bus_id);
202         if (!info->res) {
203                 dev_err(&dev->dev, "Could not reserve memory region\n");
204                 err = -ENOMEM;
205                 goto Error;
206         }
207
208         info->map.map_priv_1 = (unsigned long) ioremap(dev->resource->start,
209                                 dev->resource->end - dev->resource->start + 1);
210         if (!info->map.map_priv_1) {
211                 dev_err(&dev->dev, "Failed to ioremap flash region\n");
212                 err = -EIO;
213                 goto Error;
214         }
215
216 #if defined(__ARMEB__)
217         /*
218          * Enable erratum 44 workaround for NPUs with broken slowport
219          */
220
221         erratum44_workaround = ixp2000_has_broken_slowport();
222         dev_info(&dev->dev, "Erratum 44 workaround %s\n",
223                erratum44_workaround ? "enabled" : "disabled");
224 #endif
225
226         info->mtd = do_map_probe(plat->map_name, &info->map);
227         if (!info->mtd) {
228                 dev_err(&dev->dev, "map_probe failed\n");
229                 err = -ENXIO;
230                 goto Error;
231         }
232         info->mtd->owner = THIS_MODULE;
233
234         err = parse_mtd_partitions(info->mtd, probes, &info->partitions, 0);
235         if (err > 0) {
236                 err = add_mtd_partitions(info->mtd, info->partitions, err);
237                 if(err)
238                         dev_err(&dev->dev, "Could not parse partitions\n");
239         }
240
241         if (err)
242                 goto Error;
243
244         return 0;
245
246 Error:
247         ixp2000_flash_remove(dev);
248         return err;
249 }
250
251 static struct platform_driver ixp2000_flash_driver = {
252         .probe          = ixp2000_flash_probe,
253         .remove         = ixp2000_flash_remove,
254         .driver         = {
255                 .name   = "IXP2000-Flash",
256         },
257 };
258
259 static int __init ixp2000_flash_init(void)
260 {
261         return platform_driver_register(&ixp2000_flash_driver);
262 }
263
264 static void __exit ixp2000_flash_exit(void)
265 {
266         platform_driver_unregister(&ixp2000_flash_driver);
267 }
268
269 module_init(ixp2000_flash_init);
270 module_exit(ixp2000_flash_exit);
271 MODULE_LICENSE("GPL");
272 MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
273