xref: /openbmc/linux/drivers/char/ps3flash.c (revision e8e0929d)
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/uaccess.h>
24 
25 #include <asm/lv1call.h>
26 #include <asm/ps3stor.h>
27 
28 
29 #define DEVICE_NAME		"ps3flash"
30 
31 #define FLASH_BLOCK_SIZE	(256*1024)
32 
33 
34 struct ps3flash_private {
35 	struct mutex mutex;	/* Bounce buffer mutex */
36 	u64 chunk_sectors;
37 	int tag;		/* Start sector of buffer, -1 if invalid */
38 	bool dirty;
39 };
40 
41 static struct ps3_storage_device *ps3flash_dev;
42 
43 static int ps3flash_read_write_sectors(struct ps3_storage_device *dev,
44 				       u64 start_sector, int write)
45 {
46 	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
47 	u64 res = ps3stor_read_write_sectors(dev, dev->bounce_lpar,
48 					     start_sector, priv->chunk_sectors,
49 					     write);
50 	if (res) {
51 		dev_err(&dev->sbd.core, "%s:%u: %s failed 0x%llx\n", __func__,
52 			__LINE__, write ? "write" : "read", res);
53 		return -EIO;
54 	}
55 	return 0;
56 }
57 
58 static int ps3flash_writeback(struct ps3_storage_device *dev)
59 {
60 	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
61 	int res;
62 
63 	if (!priv->dirty || priv->tag < 0)
64 		return 0;
65 
66 	res = ps3flash_read_write_sectors(dev, priv->tag, 1);
67 	if (res)
68 		return res;
69 
70 	priv->dirty = false;
71 	return 0;
72 }
73 
74 static int ps3flash_fetch(struct ps3_storage_device *dev, u64 start_sector)
75 {
76 	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
77 	int res;
78 
79 	if (start_sector == priv->tag)
80 		return 0;
81 
82 	res = ps3flash_writeback(dev);
83 	if (res)
84 		return res;
85 
86 	priv->tag = -1;
87 
88 	res = ps3flash_read_write_sectors(dev, start_sector, 0);
89 	if (res)
90 		return res;
91 
92 	priv->tag = start_sector;
93 	return 0;
94 }
95 
96 static loff_t ps3flash_llseek(struct file *file, loff_t offset, int origin)
97 {
98 	struct ps3_storage_device *dev = ps3flash_dev;
99 	loff_t res;
100 
101 	mutex_lock(&file->f_mapping->host->i_mutex);
102 	switch (origin) {
103 	case 1:
104 		offset += file->f_pos;
105 		break;
106 	case 2:
107 		offset += dev->regions[dev->region_idx].size*dev->blk_size;
108 		break;
109 	}
110 	if (offset < 0) {
111 		res = -EINVAL;
112 		goto out;
113 	}
114 
115 	file->f_pos = offset;
116 	res = file->f_pos;
117 
118 out:
119 	mutex_unlock(&file->f_mapping->host->i_mutex);
120 	return res;
121 }
122 
123 static ssize_t ps3flash_read(char __user *userbuf, void *kernelbuf,
124 			     size_t count, loff_t *pos)
125 {
126 	struct ps3_storage_device *dev = ps3flash_dev;
127 	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
128 	u64 size, sector, offset;
129 	int res;
130 	size_t remaining, n;
131 	const void *src;
132 
133 	dev_dbg(&dev->sbd.core,
134 		"%s:%u: Reading %zu bytes at position %lld to U0x%p/K0x%p\n",
135 		__func__, __LINE__, count, *pos, userbuf, kernelbuf);
136 
137 	size = dev->regions[dev->region_idx].size*dev->blk_size;
138 	if (*pos >= size || !count)
139 		return 0;
140 
141 	if (*pos + count > size) {
142 		dev_dbg(&dev->sbd.core,
143 			"%s:%u Truncating count from %zu to %llu\n", __func__,
144 			__LINE__, count, size - *pos);
145 		count = size - *pos;
146 	}
147 
148 	sector = *pos / dev->bounce_size * priv->chunk_sectors;
149 	offset = *pos % dev->bounce_size;
150 
151 	remaining = count;
152 	do {
153 		n = min_t(u64, remaining, dev->bounce_size - offset);
154 		src = dev->bounce_buf + offset;
155 
156 		mutex_lock(&priv->mutex);
157 
158 		res = ps3flash_fetch(dev, sector);
159 		if (res)
160 			goto fail;
161 
162 		dev_dbg(&dev->sbd.core,
163 			"%s:%u: copy %lu bytes from 0x%p to U0x%p/K0x%p\n",
164 			__func__, __LINE__, n, src, userbuf, kernelbuf);
165 		if (userbuf) {
166 			if (copy_to_user(userbuf, src, n)) {
167 				res = -EFAULT;
168 				goto fail;
169 			}
170 			userbuf += n;
171 		}
172 		if (kernelbuf) {
173 			memcpy(kernelbuf, src, n);
174 			kernelbuf += n;
175 		}
176 
177 		mutex_unlock(&priv->mutex);
178 
179 		*pos += n;
180 		remaining -= n;
181 		sector += priv->chunk_sectors;
182 		offset = 0;
183 	} while (remaining > 0);
184 
185 	return count;
186 
187 fail:
188 	mutex_unlock(&priv->mutex);
189 	return res;
190 }
191 
192 static ssize_t ps3flash_write(const char __user *userbuf,
193 			      const void *kernelbuf, size_t count, loff_t *pos)
194 {
195 	struct ps3_storage_device *dev = ps3flash_dev;
196 	struct ps3flash_private *priv = ps3_system_bus_get_drvdata(&dev->sbd);
197 	u64 size, sector, offset;
198 	int res = 0;
199 	size_t remaining, n;
200 	void *dst;
201 
202 	dev_dbg(&dev->sbd.core,
203 		"%s:%u: Writing %zu bytes at position %lld from U0x%p/K0x%p\n",
204 		__func__, __LINE__, count, *pos, userbuf, kernelbuf);
205 
206 	size = dev->regions[dev->region_idx].size*dev->blk_size;
207 	if (*pos >= size || !count)
208 		return 0;
209 
210 	if (*pos + count > size) {
211 		dev_dbg(&dev->sbd.core,
212 			"%s:%u Truncating count from %zu to %llu\n", __func__,
213 			__LINE__, count, size - *pos);
214 		count = size - *pos;
215 	}
216 
217 	sector = *pos / dev->bounce_size * priv->chunk_sectors;
218 	offset = *pos % dev->bounce_size;
219 
220 	remaining = count;
221 	do {
222 		n = min_t(u64, remaining, dev->bounce_size - offset);
223 		dst = dev->bounce_buf + offset;
224 
225 		mutex_lock(&priv->mutex);
226 
227 		if (n != dev->bounce_size)
228 			res = ps3flash_fetch(dev, sector);
229 		else if (sector != priv->tag)
230 			res = ps3flash_writeback(dev);
231 		if (res)
232 			goto fail;
233 
234 		dev_dbg(&dev->sbd.core,
235 			"%s:%u: copy %lu bytes from U0x%p/K0x%p to 0x%p\n",
236 			__func__, __LINE__, n, userbuf, kernelbuf, dst);
237 		if (userbuf) {
238 			if (copy_from_user(dst, userbuf, n)) {
239 				res = -EFAULT;
240 				goto fail;
241 			}
242 			userbuf += n;
243 		}
244 		if (kernelbuf) {
245 			memcpy(dst, kernelbuf, n);
246 			kernelbuf += n;
247 		}
248 
249 		priv->tag = sector;
250 		priv->dirty = true;
251 
252 		mutex_unlock(&priv->mutex);
253 
254 		*pos += n;
255 		remaining -= n;
256 		sector += priv->chunk_sectors;
257 		offset = 0;
258 	} while (remaining > 0);
259 
260 	return count;
261 
262 fail:
263 	mutex_unlock(&priv->mutex);
264 	return res;
265 }
266 
267 static ssize_t ps3flash_user_read(struct file *file, char __user *buf,
268 				  size_t count, loff_t *pos)
269 {
270 	return ps3flash_read(buf, NULL, count, pos);
271 }
272 
273 static ssize_t ps3flash_user_write(struct file *file, const char __user *buf,
274 				   size_t count, loff_t *pos)
275 {
276 	return ps3flash_write(buf, NULL, count, pos);
277 }
278 
279 static ssize_t ps3flash_kernel_read(void *buf, size_t count, loff_t pos)
280 {
281 	return ps3flash_read(NULL, buf, count, &pos);
282 }
283 
284 static ssize_t ps3flash_kernel_write(const void *buf, size_t count,
285 				     loff_t pos)
286 {
287 	ssize_t res;
288 	int wb;
289 
290 	res = ps3flash_write(NULL, buf, count, &pos);
291 	if (res < 0)
292 		return res;
293 
294 	/* Make kernel writes synchronous */
295 	wb = ps3flash_writeback(ps3flash_dev);
296 	if (wb)
297 		return wb;
298 
299 	return res;
300 }
301 
302 static int ps3flash_flush(struct file *file, fl_owner_t id)
303 {
304 	return ps3flash_writeback(ps3flash_dev);
305 }
306 
307 static int ps3flash_fsync(struct file *file, struct dentry *dentry,
308 			  int datasync)
309 {
310 	return ps3flash_writeback(ps3flash_dev);
311 }
312 
313 static irqreturn_t ps3flash_interrupt(int irq, void *data)
314 {
315 	struct ps3_storage_device *dev = data;
316 	int res;
317 	u64 tag, status;
318 
319 	res = lv1_storage_get_async_status(dev->sbd.dev_id, &tag, &status);
320 
321 	if (tag != dev->tag)
322 		dev_err(&dev->sbd.core,
323 			"%s:%u: tag mismatch, got %llx, expected %llx\n",
324 			__func__, __LINE__, tag, dev->tag);
325 
326 	if (res) {
327 		dev_err(&dev->sbd.core, "%s:%u: res=%d status=0x%llx\n",
328 			__func__, __LINE__, res, status);
329 	} else {
330 		dev->lv1_status = status;
331 		complete(&dev->done);
332 	}
333 	return IRQ_HANDLED;
334 }
335 
336 static const struct file_operations ps3flash_fops = {
337 	.owner	= THIS_MODULE,
338 	.llseek	= ps3flash_llseek,
339 	.read	= ps3flash_user_read,
340 	.write	= ps3flash_user_write,
341 	.flush	= ps3flash_flush,
342 	.fsync	= ps3flash_fsync,
343 };
344 
345 static const struct ps3_os_area_flash_ops ps3flash_kernel_ops = {
346 	.read	= ps3flash_kernel_read,
347 	.write	= ps3flash_kernel_write,
348 };
349 
350 static struct miscdevice ps3flash_misc = {
351 	.minor	= MISC_DYNAMIC_MINOR,
352 	.name	= DEVICE_NAME,
353 	.fops	= &ps3flash_fops,
354 };
355 
356 static int __devinit ps3flash_probe(struct ps3_system_bus_device *_dev)
357 {
358 	struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
359 	struct ps3flash_private *priv;
360 	int error;
361 	unsigned long tmp;
362 
363 	tmp = dev->regions[dev->region_idx].start*dev->blk_size;
364 	if (tmp % FLASH_BLOCK_SIZE) {
365 		dev_err(&dev->sbd.core,
366 			"%s:%u region start %lu is not aligned\n", __func__,
367 			__LINE__, tmp);
368 		return -EINVAL;
369 	}
370 	tmp = dev->regions[dev->region_idx].size*dev->blk_size;
371 	if (tmp % FLASH_BLOCK_SIZE) {
372 		dev_err(&dev->sbd.core,
373 			"%s:%u region size %lu is not aligned\n", __func__,
374 			__LINE__, tmp);
375 		return -EINVAL;
376 	}
377 
378 	/* use static buffer, kmalloc cannot allocate 256 KiB */
379 	if (!ps3flash_bounce_buffer.address)
380 		return -ENODEV;
381 
382 	if (ps3flash_dev) {
383 		dev_err(&dev->sbd.core,
384 			"Only one FLASH device is supported\n");
385 		return -EBUSY;
386 	}
387 
388 	ps3flash_dev = dev;
389 
390 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
391 	if (!priv) {
392 		error = -ENOMEM;
393 		goto fail;
394 	}
395 
396 	ps3_system_bus_set_drvdata(&dev->sbd, priv);
397 	mutex_init(&priv->mutex);
398 	priv->tag = -1;
399 
400 	dev->bounce_size = ps3flash_bounce_buffer.size;
401 	dev->bounce_buf = ps3flash_bounce_buffer.address;
402 	priv->chunk_sectors = dev->bounce_size / dev->blk_size;
403 
404 	error = ps3stor_setup(dev, ps3flash_interrupt);
405 	if (error)
406 		goto fail_free_priv;
407 
408 	ps3flash_misc.parent = &dev->sbd.core;
409 	error = misc_register(&ps3flash_misc);
410 	if (error) {
411 		dev_err(&dev->sbd.core, "%s:%u: misc_register failed %d\n",
412 			__func__, __LINE__, error);
413 		goto fail_teardown;
414 	}
415 
416 	dev_info(&dev->sbd.core, "%s:%u: registered misc device %d\n",
417 		 __func__, __LINE__, ps3flash_misc.minor);
418 
419 	ps3_os_area_flash_register(&ps3flash_kernel_ops);
420 	return 0;
421 
422 fail_teardown:
423 	ps3stor_teardown(dev);
424 fail_free_priv:
425 	kfree(priv);
426 	ps3_system_bus_set_drvdata(&dev->sbd, NULL);
427 fail:
428 	ps3flash_dev = NULL;
429 	return error;
430 }
431 
432 static int ps3flash_remove(struct ps3_system_bus_device *_dev)
433 {
434 	struct ps3_storage_device *dev = to_ps3_storage_device(&_dev->core);
435 
436 	ps3_os_area_flash_register(NULL);
437 	misc_deregister(&ps3flash_misc);
438 	ps3stor_teardown(dev);
439 	kfree(ps3_system_bus_get_drvdata(&dev->sbd));
440 	ps3_system_bus_set_drvdata(&dev->sbd, NULL);
441 	ps3flash_dev = NULL;
442 	return 0;
443 }
444 
445 
446 static struct ps3_system_bus_driver ps3flash = {
447 	.match_id	= PS3_MATCH_ID_STOR_FLASH,
448 	.core.name	= DEVICE_NAME,
449 	.core.owner	= THIS_MODULE,
450 	.probe		= ps3flash_probe,
451 	.remove		= ps3flash_remove,
452 	.shutdown	= ps3flash_remove,
453 };
454 
455 
456 static int __init ps3flash_init(void)
457 {
458 	return ps3_system_bus_driver_register(&ps3flash);
459 }
460 
461 static void __exit ps3flash_exit(void)
462 {
463 	ps3_system_bus_driver_unregister(&ps3flash);
464 }
465 
466 module_init(ps3flash_init);
467 module_exit(ps3flash_exit);
468 
469 MODULE_LICENSE("GPL");
470 MODULE_DESCRIPTION("PS3 FLASH ROM Storage Driver");
471 MODULE_AUTHOR("Sony Corporation");
472 MODULE_ALIAS(PS3_MODULE_ALIAS_STOR_FLASH);
473