Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
[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         int             nr_banks;
46 };
47
48 static inline unsigned long flash_bank_setup(struct map_info *map, unsigned long ofs)
49 {
50         unsigned long (*set_bank)(unsigned long) =
51                 (unsigned long(*)(unsigned long))map->map_priv_2;
52
53         return (set_bank ? set_bank(ofs) : ofs);
54 }
55
56 #ifdef __ARMEB__
57 /*
58  * Rev A0 and A1 of IXP2400 silicon have a broken addressing unit which
59  * causes the lower address bits to be XORed with 0x11 on 8 bit accesses
60  * and XORed with 0x10 on 16 bit accesses. See the spec update, erratum 44.
61  */
62 static int erratum44_workaround = 0;
63
64 static inline unsigned long address_fix8_write(unsigned long addr)
65 {
66         if (erratum44_workaround) {
67                 return (addr ^ 3);
68         }
69         return addr;
70 }
71 #else
72
73 #define address_fix8_write(x)   (x)
74 #endif
75
76 static map_word ixp2000_flash_read8(struct map_info *map, unsigned long ofs)
77 {
78         map_word val;
79
80         val.x[0] =  *((u8 *)(map->map_priv_1 + flash_bank_setup(map, ofs)));
81         return val;
82 }
83
84 /*
85  * We can't use the standard memcpy due to the broken SlowPort
86  * address translation on rev A0 and A1 silicon and the fact that
87  * we have banked flash.
88  */
89 static void ixp2000_flash_copy_from(struct map_info *map, void *to,
90                               unsigned long from, ssize_t len)
91 {
92         from = flash_bank_setup(map, from);
93         while(len--)
94                 *(__u8 *) to++ = *(__u8 *)(map->map_priv_1 + from++);
95 }
96
97 static void ixp2000_flash_write8(struct map_info *map, map_word d, unsigned long ofs)
98 {
99         *(__u8 *) (address_fix8_write(map->map_priv_1 +
100                                       flash_bank_setup(map, ofs))) = d.x[0];
101 }
102
103 static void ixp2000_flash_copy_to(struct map_info *map, unsigned long to,
104                             const void *from, ssize_t len)
105 {
106         to = flash_bank_setup(map, to);
107         while(len--) {
108                 unsigned long tmp = address_fix8_write(map->map_priv_1 + to++);
109                 *(__u8 *)(tmp) = *(__u8 *)(from++);
110         }
111 }
112
113
114 static int ixp2000_flash_remove(struct device *_dev)
115 {
116         struct platform_device *dev = to_platform_device(_dev);
117         struct flash_platform_data *plat = dev->dev.platform_data;
118         struct ixp2000_flash_info *info = dev_get_drvdata(&dev->dev);
119
120         dev_set_drvdata(&dev->dev, NULL);
121
122         if(!info)
123                 return 0;
124
125         if (info->mtd) {
126                 del_mtd_partitions(info->mtd);
127                 map_destroy(info->mtd);
128         }
129         if (info->map.map_priv_1)
130                 iounmap((void *) info->map.map_priv_1);
131
132         kfree(info->partitions);
133
134         if (info->res) {
135                 release_resource(info->res);
136                 kfree(info->res);
137         }
138
139         if (plat->exit)
140                 plat->exit();
141
142         return 0;
143 }
144
145
146 static int ixp2000_flash_probe(struct device *_dev)
147 {
148         static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };
149         struct platform_device *dev = to_platform_device(_dev);
150         struct ixp2000_flash_data *ixp_data = dev->dev.platform_data;
151         struct flash_platform_data *plat;
152         struct ixp2000_flash_info *info;
153         unsigned long window_size;
154         int err = -1;
155
156         if (!ixp_data)
157                 return -ENODEV;
158
159         plat = ixp_data->platform_data;
160         if (!plat)
161                 return -ENODEV;
162
163         window_size = dev->resource->end - dev->resource->start + 1;
164         dev_info(_dev, "Probe of IXP2000 flash(%d banks x %dMiB)\n",
165                         ixp_data->nr_banks, ((u32)window_size >> 20));
166
167         if (plat->width != 1) {
168                 dev_err(_dev, "IXP2000 MTD map only supports 8-bit mode, asking for %d\n",
169                                 plat->width * 8);
170                 return -EIO;
171         }
172
173         info = kmalloc(sizeof(struct ixp2000_flash_info), GFP_KERNEL);
174         if(!info) {
175                 err = -ENOMEM;
176                 goto Error;
177         }
178         memzero(info, sizeof(struct ixp2000_flash_info));
179
180         dev_set_drvdata(&dev->dev, info);
181
182         /*
183          * Tell the MTD layer we're not 1:1 mapped so that it does
184          * not attempt to do a direct access on us.
185          */
186         info->map.phys = NO_XIP;
187
188         info->nr_banks = ixp_data->nr_banks;
189         info->map.size = ixp_data->nr_banks * window_size;
190         info->map.bankwidth = 1;
191
192         /*
193          * map_priv_2 is used to store a ptr to to the bank_setup routine
194          */
195         info->map.map_priv_2 = (unsigned long) ixp_data->bank_setup;
196
197         info->map.name = dev->dev.bus_id;
198         info->map.read = ixp2000_flash_read8;
199         info->map.write = ixp2000_flash_write8;
200         info->map.copy_from = ixp2000_flash_copy_from;
201         info->map.copy_to = ixp2000_flash_copy_to;
202
203         info->res = request_mem_region(dev->resource->start,
204                         dev->resource->end - dev->resource->start + 1,
205                         dev->dev.bus_id);
206         if (!info->res) {
207                 dev_err(_dev, "Could not reserve memory region\n");
208                 err = -ENOMEM;
209                 goto Error;
210         }
211
212         info->map.map_priv_1 = (unsigned long) ioremap(dev->resource->start,
213                                 dev->resource->end - dev->resource->start + 1);
214         if (!info->map.map_priv_1) {
215                 dev_err(_dev, "Failed to ioremap flash region\n");
216                 err = -EIO;
217                 goto Error;
218         }
219
220 #if defined(__ARMEB__)
221         /*
222          * Enable erratum 44 workaround for NPUs with broken slowport
223          */
224
225         erratum44_workaround = ixp2000_has_broken_slowport();
226         dev_info(_dev, "Erratum 44 workaround %s\n",
227                erratum44_workaround ? "enabled" : "disabled");
228 #endif
229
230         info->mtd = do_map_probe(plat->map_name, &info->map);
231         if (!info->mtd) {
232                 dev_err(_dev, "map_probe failed\n");
233                 err = -ENXIO;
234                 goto Error;
235         }
236         info->mtd->owner = THIS_MODULE;
237
238         err = parse_mtd_partitions(info->mtd, probes, &info->partitions, 0);
239         if (err > 0) {
240                 err = add_mtd_partitions(info->mtd, info->partitions, err);
241                 if(err)
242                         dev_err(_dev, "Could not parse partitions\n");
243         }
244
245         if (err)
246                 goto Error;
247
248         return 0;
249
250 Error:
251         ixp2000_flash_remove(_dev);
252         return err;
253 }
254
255 static struct device_driver ixp2000_flash_driver = {
256         .name           = "IXP2000-Flash",
257         .bus            = &platform_bus_type,
258         .probe          = &ixp2000_flash_probe,
259         .remove         = &ixp2000_flash_remove
260 };
261
262 static int __init ixp2000_flash_init(void)
263 {
264         return driver_register(&ixp2000_flash_driver);
265 }
266
267 static void __exit ixp2000_flash_exit(void)
268 {
269         driver_unregister(&ixp2000_flash_driver);
270 }
271
272 module_init(ixp2000_flash_init);
273 module_exit(ixp2000_flash_exit);
274 MODULE_LICENSE("GPL");
275 MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
276