606048b72bcf2e0adbebf8590a92e4f1b55fd5b5
[safe/jmp/linux-2.6] / drivers / char / ps3flash.c
1 /*
2  * PS3 FLASH ROM Storage Driver
3  *
4  * Copyright (C) 2007 Sony Computer Entertainment Inc.
5  * Copyright 2007 Sony Corp.
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published
9  * by the Free Software Foundation; version 2 of the License.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License along
17  * with this program; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19  */
20
21 #include <linux/fs.h>
22 #include <linux/miscdevice.h>
23 #include <linux/slab.h>
24 #include <linux/uaccess.h>
25
26 #include <asm/lv1call.h>
27 #include <asm/ps3stor.h>
28
29
30 #define DEVICE_NAME             "ps3flash"
31
32 #define FLASH_BLOCK_SIZE        (256*1024)
33
34
35 struct ps3flash_private {
36         struct mutex mutex;     /* Bounce buffer mutex */
37         u64 chunk_sectors;
38         int tag;                /* Start sector of buffer, -1 if invalid */
39         bool dirty;
40 };
41
42 static struct ps3_storage_device *ps3flash_dev;
43
44 static int ps3flash_read_write_sectors(struct ps3_storage_device *dev,
45                                        u64 start_sector, int write)
46 {
47         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
48         u64 res = ps3stor_read_write_sectors(dev, dev->bounce_lpar,
49                                              start_sector, priv->chunk_sectors,
50                                              write);
51         if (res) {
52                 dev_err(&dev->sbd.core, "%s:%u: %s failed 0x%llx\n", __func__,
53                         __LINE__, write ? "write" : "read", res);
54                 return -EIO;
55         }
56         return 0;
57 }
58
59 static int ps3flash_writeback(struct ps3_storage_device *dev)
60 {
61         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
62         int res;
63
64         if (!priv->dirty || priv->tag < 0)
65                 return 0;
66
67         res = ps3flash_read_write_sectors(dev, priv->tag, 1);
68         if (res)
69                 return res;
70
71         priv->dirty = false;
72         return 0;
73 }
74
75 static int ps3flash_fetch(struct ps3_storage_device *dev, u64 start_sector)
76 {
77         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
78         int res;
79
80         if (start_sector == priv->tag)
81                 return 0;
82
83         res = ps3flash_writeback(dev);
84         if (res)
85                 return res;
86
87         priv->tag = -1;
88
89         res = ps3flash_read_write_sectors(dev, start_sector, 0);
90         if (res)
91                 return res;
92
93         priv->tag = start_sector;
94         return 0;
95 }
96
97 static loff_t ps3flash_llseek(struct file *file, loff_t offset, int origin)
98 {
99         struct ps3_storage_device *dev = ps3flash_dev;
100         loff_t res;
101
102         mutex_lock(&file->f_mapping->host->i_mutex);
103         switch (origin) {
104         case 1:
105                 offset += file->f_pos;
106                 break;
107         case 2:
108                 offset += dev->regions[dev->region_idx].size*dev->blk_size;
109                 break;
110         }
111         if (offset < 0) {
112                 res = -EINVAL;
113                 goto out;
114         }
115
116         file->f_pos = offset;
117         res = file->f_pos;
118
119 out:
120         mutex_unlock(&file->f_mapping->host->i_mutex);
121         return res;
122 }
123
124 static ssize_t ps3flash_read(char __user *userbuf, void *kernelbuf,
125                              size_t count, loff_t *pos)
126 {
127         struct ps3_storage_device *dev = ps3flash_dev;
128         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
129         u64 size, sector, offset;
130         int res;
131         size_t remaining, n;
132         const void *src;
133
134         dev_dbg(&dev->sbd.core,
135                 "%s:%u: Reading %zu bytes at position %lld to U0x%p/K0x%p\n",
136                 __func__, __LINE__, count, *pos, userbuf, kernelbuf);
137
138         size = dev->regions[dev->region_idx].size*dev->blk_size;
139         if (*pos >= size || !count)
140                 return 0;
141
142         if (*pos + count > size) {
143                 dev_dbg(&dev->sbd.core,
144                         "%s:%u Truncating count from %zu to %llu\n", __func__,
145                         __LINE__, count, size - *pos);
146                 count = size - *pos;
147         }
148
149         sector = *pos / dev->bounce_size * priv->chunk_sectors;
150         offset = *pos % dev->bounce_size;
151
152         remaining = count;
153         do {
154                 n = min_t(u64, remaining, dev->bounce_size - offset);
155                 src = dev->bounce_buf + offset;
156
157                 mutex_lock(&priv->mutex);
158
159                 res = ps3flash_fetch(dev, sector);
160                 if (res)
161                         goto fail;
162
163                 dev_dbg(&dev->sbd.core,
164                         "%s:%u: copy %lu bytes from 0x%p to U0x%p/K0x%p\n",
165                         __func__, __LINE__, n, src, userbuf, kernelbuf);
166                 if (userbuf) {
167                         if (copy_to_user(userbuf, src, n)) {
168                                 res = -EFAULT;
169                                 goto fail;
170                         }
171                         userbuf += n;
172                 }
173                 if (kernelbuf) {
174                         memcpy(kernelbuf, src, n);
175                         kernelbuf += n;
176                 }
177
178                 mutex_unlock(&priv->mutex);
179
180                 *pos += n;
181                 remaining -= n;
182                 sector += priv->chunk_sectors;
183                 offset = 0;
184         } while (remaining > 0);
185
186         return count;
187
188 fail:
189         mutex_unlock(&priv->mutex);
190         return res;
191 }
192
193 static ssize_t ps3flash_write(const char __user *userbuf,
194                               const void *kernelbuf, size_t count, loff_t *pos)
195 {
196         struct ps3_storage_device *dev = ps3flash_dev;
197         struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
198         u64 size, sector, offset;
199         int res = 0;
200         size_t remaining, n;
201         void *dst;
202
203         dev_dbg(&dev->sbd.core,
204                 "%s:%u: Writing %zu bytes at position %lld from U0x%p/K0x%p\n",
205                 __func__, __LINE__, count, *pos, userbuf, kernelbuf);
206
207         size = dev->regions[dev->region_idx].size*dev->blk_size;
208         if (*pos >= size || !count)
209                 return 0;
210
211         if (*pos + count > size) {
212                 dev_dbg(&dev->sbd.core,
213                         "%s:%u Truncating count from %zu to %llu\n", __func__,
214                         __LINE__, count, size - *pos);
215                 count = size - *pos;
216         }
217
218         sector = *pos / dev->bounce_size * priv->chunk_sectors;
219         offset = *pos % dev->bounce_size;
220
221         remaining = count;
222         do {
223                 n = min_t(u64, remaining, dev->bounce_size - offset);
224                 dst = dev->bounce_buf + offset;
225
226                 mutex_lock(&priv->mutex);
227
228                 if (n != dev->bounce_size)
229                         res = ps3flash_fetch(dev, sector);
230                 else if (sector != priv->tag)
231                         res = ps3flash_writeback(dev);
232                 if (res)
233                         goto fail;
234
235                 dev_dbg(&dev->sbd.core,
236                         "%s:%u: copy %lu bytes from U0x%p/K0x%p to 0x%p\n",
237                         __func__, __LINE__, n, userbuf, kernelbuf, dst);
238                 if (userbuf) {
239                         if (copy_from_user(dst, userbuf, n)) {
240                                 res = -EFAULT;
241                                 goto fail;
242                         }
243                         userbuf += n;
244                 }
245                 if (kernelbuf) {
246                         memcpy(dst, kernelbuf, n);
247                         kernelbuf += n;
248                 }
249
250                 priv->tag = sector;
251                 priv->dirty = true;
252
253                 mutex_unlock(&priv->mutex);
254
255                 *pos += n;
256                 remaining -= n;
257                 sector += priv->chunk_sectors;
258                 offset = 0;
259         } while (remaining > 0);
260
261         return count;
262
263 fail:
264         mutex_unlock(&priv->mutex);
265         return res;
266 }
267
268 static ssize_t ps3flash_user_read(struct file *file, char __user *buf,
269                                   size_t count, loff_t *pos)
270 {
271         return ps3flash_read(buf, NULL, count, pos);
272 }
273
274 static ssize_t ps3flash_user_write(struct file *file, const char __user *buf,
275                                    size_t count, loff_t *pos)
276 {
277         return ps3flash_write(buf, NULL, count, pos);
278 }
279
280 static ssize_t ps3flash_kernel_read(void *buf, size_t count, loff_t pos)
281 {
282         return ps3flash_read(NULL, buf, count, &pos);
283 }
284
285 static ssize_t ps3flash_kernel_write(const void *buf, size_t count,
286                                      loff_t pos)
287 {
288         ssize_t res;
289         int wb;
290
291         res = ps3flash_write(NULL, buf, count, &pos);
292         if (res < 0)
293                 return res;
294
295         /* Make kernel writes synchronous */
296         wb = ps3flash_writeback(ps3flash_dev);
297         if (wb)
298                 return wb;
299
300         return res;
301 }
302
303 static int ps3flash_flush(struct file *file, fl_owner_t id)
304 {
305         return ps3flash_writeback(ps3flash_dev);
306 }
307
308 static int ps3flash_fsync(struct file *file, struct dentry *dentry,
309                           int datasync)
310 {
311         return ps3flash_writeback(ps3flash_dev);
312 }
313
314 static irqreturn_t ps3flash_interrupt(int irq, void *data)
315 {
316         struct ps3_storage_device *dev = data;
317         int res;
318         u64 tag, status;
319
320         res = lv1_storage_get_async_status(dev->sbd.dev_id, &tag, &status);
321
322         if (tag != dev->tag)
323                 dev_err(&dev->sbd.core,
324                         "%s:%u: tag mismatch, got %llx, expected %llx\n",
325                         __func__, __LINE__, tag, dev->tag);
326
327         if (res) {
328                 dev_err(&dev->sbd.core, "%s:%u: res=%d status=0x%llx\n",
329                         __func__, __LINE__, res, status);
330         } else {
331                 dev->lv1_status = status;
332                 complete(&dev->done);
333         }
334         return IRQ_HANDLED;
335 }
336
337 static const struct file_operations ps3flash_fops = {
338         .owner  = THIS_MODULE,
339         .llseek = ps3flash_llseek,
340         .read   = ps3flash_user_read,
341         .write  = ps3flash_user_write,
342         .flush  = ps3flash_flush,
343         .fsync  = ps3flash_fsync,
344 };
345
346 static const struct ps3_os_area_flash_ops ps3flash_kernel_ops = {
347         .read   = ps3flash_kernel_read,
348         .write  = ps3flash_kernel_write,
349 };
350
351 static struct miscdevice ps3flash_misc = {
352         .minor  = MISC_DYNAMIC_MINOR,
353         .name   = DEVICE_NAME,
354         .fops   = &ps3flash_fops,
355 };
356
357 static int __devinit ps3flash_probe(struct ps3_system_bus_device *_dev)
358 {
359         struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
360         struct ps3flash_private *priv;
361         int error;
362         unsigned long tmp;
363
364         tmp = dev->regions[dev->region_idx].start*dev->blk_size;
365         if (tmp % FLASH_BLOCK_SIZE) {
366                 dev_err(&dev->sbd.core,
367                         "%s:%u region start %lu is not aligned\n", __func__,
368                         __LINE__, tmp);
369                 return -EINVAL;
370         }
371         tmp = dev->regions[dev->region_idx].size*dev->blk_size;
372         if (tmp % FLASH_BLOCK_SIZE) {
373                 dev_err(&dev->sbd.core,
374                         "%s:%u region size %lu is not aligned\n", __func__,
375                         __LINE__, tmp);
376                 return -EINVAL;
377         }
378
379         /* use static buffer, kmalloc cannot allocate 256 KiB */
380         if (!ps3flash_bounce_buffer.address)
381                 return -ENODEV;
382
383         if (ps3flash_dev) {
384                 dev_err(&dev->sbd.core,
385                         "Only one FLASH device is supported\n");
386                 return -EBUSY;
387         }
388
389         ps3flash_dev = dev;
390
391         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
392         if (!priv) {
393                 error = -ENOMEM;
394                 goto fail;
395         }
396
397         ps3_system_bus_set_drvdata(&dev->sbd, priv);
398         mutex_init(&priv->mutex);
399         priv->tag = -1;
400
401         dev->bounce_size = ps3flash_bounce_buffer.size;
402         dev->bounce_buf = ps3flash_bounce_buffer.address;
403         priv->chunk_sectors = dev->bounce_size / dev->blk_size;
404
405         error = ps3stor_setup(dev, ps3flash_interrupt);
406         if (error)
407                 goto fail_free_priv;
408
409         ps3flash_misc.parent = &dev->sbd.core;
410         error = misc_register(&ps3flash_misc);
411         if (error) {
412                 dev_err(&dev->sbd.core, "%s:%u: misc_register failed %d\n",
413                         __func__, __LINE__, error);
414                 goto fail_teardown;
415         }
416
417         dev_info(&dev->sbd.core, "%s:%u: registered misc device %d\n",
418                  __func__, __LINE__, ps3flash_misc.minor);
419
420         ps3_os_area_flash_register(&ps3flash_kernel_ops);
421         return 0;
422
423 fail_teardown:
424         ps3stor_teardown(dev);
425 fail_free_priv:
426         kfree(priv);
427         ps3_system_bus_set_drvdata(&dev->sbd, NULL);
428 fail:
429         ps3flash_dev = NULL;
430         return error;
431 }
432
433 static int ps3flash_remove(struct ps3_system_bus_device *_dev)
434 {
435         struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
436
437         ps3_os_area_flash_register(NULL);
438         misc_deregister(&ps3flash_misc);
439         ps3stor_teardown(dev);
440         kfree(ps3_system_bus_get_drvdata(&dev->sbd));
441         ps3_system_bus_set_drvdata(&dev->sbd, NULL);
442         ps3flash_dev = NULL;
443         return 0;
444 }
445
446
447 static struct ps3_system_bus_driver ps3flash = {
448         .match_id       = PS3_MATCH_ID_STOR_FLASH,
449         .core.name      = DEVICE_NAME,
450         .core.owner     = THIS_MODULE,
451         .probe          = ps3flash_probe,
452         .remove         = ps3flash_remove,
453         .shutdown       = ps3flash_remove,
454 };
455
456
457 static int __init ps3flash_init(void)
458 {
459         return ps3_system_bus_driver_register(&ps3flash);
460 }
461
462 static void __exit ps3flash_exit(void)
463 {
464         ps3_system_bus_driver_unregister(&ps3flash);
465 }
466
467 module_init(ps3flash_init);
468 module_exit(ps3flash_exit);
469
470 MODULE_LICENSE("GPL");
471 MODULE_DESCRIPTION("PS3 FLASH ROM Storage Driver");
472 MODULE_AUTHOR("Sony Corporation");
473 MODULE_ALIAS(PS3_MODULE_ALIAS_STOR_FLASH);