xref: /openbmc/linux/drivers/char/ps3flash.c (revision 1fa6ac37)
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, 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