xref: /linux/drivers/mtd/lpddr/lpddr_cmds.c (revision fb72014d98afd51e85aab9c061344ef32d615606)
1 /*
2  * LPDDR flash memory device operations. This module provides read, write,
3  * erase, lock/unlock support for LPDDR flash memories
4  * (C) 2008 Korolev Alexey <akorolev@infradead.org>
5  * (C) 2008 Vasiliy Leonenko <vasiliy.leonenko@gmail.com>
6  * Many thanks to Roman Borisov for intial enabling
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * as published by the Free Software Foundation; either version 2
11  * of the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
21  * 02110-1301, USA.
22  * TODO:
23  * Implement VPP management
24  * Implement XIP support
25  * Implement OTP support
26  */
27 #include <linux/mtd/pfow.h>
28 #include <linux/mtd/qinfo.h>
29 #include <linux/slab.h>
30 
31 static int lpddr_read(struct mtd_info *mtd, loff_t adr, size_t len,
32 					size_t *retlen, u_char *buf);
33 static int lpddr_write_buffers(struct mtd_info *mtd, loff_t to,
34 				size_t len, size_t *retlen, const u_char *buf);
35 static int lpddr_writev(struct mtd_info *mtd, const struct kvec *vecs,
36 				unsigned long count, loff_t to, size_t *retlen);
37 static int lpddr_erase(struct mtd_info *mtd, struct erase_info *instr);
38 static int lpddr_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
39 static int lpddr_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
40 static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
41 			size_t *retlen, void **mtdbuf, resource_size_t *phys);
42 static void lpddr_unpoint(struct mtd_info *mtd, loff_t adr, size_t len);
43 static int get_chip(struct map_info *map, struct flchip *chip, int mode);
44 static int chip_ready(struct map_info *map, struct flchip *chip, int mode);
45 static void put_chip(struct map_info *map, struct flchip *chip);
46 
47 struct mtd_info *lpddr_cmdset(struct map_info *map)
48 {
49 	struct lpddr_private *lpddr = map->fldrv_priv;
50 	struct flchip_shared *shared;
51 	struct flchip *chip;
52 	struct mtd_info *mtd;
53 	int numchips;
54 	int i, j;
55 
56 	mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
57 	if (!mtd) {
58 		printk(KERN_ERR "Failed to allocate memory for MTD device\n");
59 		return NULL;
60 	}
61 	mtd->priv = map;
62 	mtd->type = MTD_NORFLASH;
63 
64 	/* Fill in the default mtd operations */
65 	mtd->read = lpddr_read;
66 	mtd->type = MTD_NORFLASH;
67 	mtd->flags = MTD_CAP_NORFLASH;
68 	mtd->flags &= ~MTD_BIT_WRITEABLE;
69 	mtd->erase = lpddr_erase;
70 	mtd->write = lpddr_write_buffers;
71 	mtd->writev = lpddr_writev;
72 	mtd->read_oob = NULL;
73 	mtd->write_oob = NULL;
74 	mtd->sync = NULL;
75 	mtd->lock = lpddr_lock;
76 	mtd->unlock = lpddr_unlock;
77 	mtd->suspend = NULL;
78 	mtd->resume = NULL;
79 	if (map_is_linear(map)) {
80 		mtd->point = lpddr_point;
81 		mtd->unpoint = lpddr_unpoint;
82 	}
83 	mtd->block_isbad = NULL;
84 	mtd->block_markbad = NULL;
85 	mtd->size = 1 << lpddr->qinfo->DevSizeShift;
86 	mtd->erasesize = 1 << lpddr->qinfo->UniformBlockSizeShift;
87 	mtd->writesize = 1 << lpddr->qinfo->BufSizeShift;
88 
89 	shared = kmalloc(sizeof(struct flchip_shared) * lpddr->numchips,
90 						GFP_KERNEL);
91 	if (!shared) {
92 		kfree(lpddr);
93 		kfree(mtd);
94 		return NULL;
95 	}
96 
97 	chip = &lpddr->chips[0];
98 	numchips = lpddr->numchips / lpddr->qinfo->HWPartsNum;
99 	for (i = 0; i < numchips; i++) {
100 		shared[i].writing = shared[i].erasing = NULL;
101 		spin_lock_init(&shared[i].lock);
102 		for (j = 0; j < lpddr->qinfo->HWPartsNum; j++) {
103 			*chip = lpddr->chips[i];
104 			chip->start += j << lpddr->chipshift;
105 			chip->oldstate = chip->state = FL_READY;
106 			chip->priv = &shared[i];
107 			/* those should be reset too since
108 			   they create memory references. */
109 			init_waitqueue_head(&chip->wq);
110 			spin_lock_init(&chip->_spinlock);
111 			chip->mutex = &chip->_spinlock;
112 			chip++;
113 		}
114 	}
115 
116 	return mtd;
117 }
118 EXPORT_SYMBOL(lpddr_cmdset);
119 
120 static int wait_for_ready(struct map_info *map, struct flchip *chip,
121 		unsigned int chip_op_time)
122 {
123 	unsigned int timeo, reset_timeo, sleep_time;
124 	unsigned int dsr;
125 	flstate_t chip_state = chip->state;
126 	int ret = 0;
127 
128 	/* set our timeout to 8 times the expected delay */
129 	timeo = chip_op_time * 8;
130 	if (!timeo)
131 		timeo = 500000;
132 	reset_timeo = timeo;
133 	sleep_time = chip_op_time / 2;
134 
135 	for (;;) {
136 		dsr = CMDVAL(map_read(map, map->pfow_base + PFOW_DSR));
137 		if (dsr & DSR_READY_STATUS)
138 			break;
139 		if (!timeo) {
140 			printk(KERN_ERR "%s: Flash timeout error state %d \n",
141 							map->name, chip_state);
142 			ret = -ETIME;
143 			break;
144 		}
145 
146 		/* OK Still waiting. Drop the lock, wait a while and retry. */
147 		spin_unlock(chip->mutex);
148 		if (sleep_time >= 1000000/HZ) {
149 			/*
150 			 * Half of the normal delay still remaining
151 			 * can be performed with a sleeping delay instead
152 			 * of busy waiting.
153 			 */
154 			msleep(sleep_time/1000);
155 			timeo -= sleep_time;
156 			sleep_time = 1000000/HZ;
157 		} else {
158 			udelay(1);
159 			cond_resched();
160 			timeo--;
161 		}
162 		spin_lock(chip->mutex);
163 
164 		while (chip->state != chip_state) {
165 			/* Someone's suspended the operation: sleep */
166 			DECLARE_WAITQUEUE(wait, current);
167 			set_current_state(TASK_UNINTERRUPTIBLE);
168 			add_wait_queue(&chip->wq, &wait);
169 			spin_unlock(chip->mutex);
170 			schedule();
171 			remove_wait_queue(&chip->wq, &wait);
172 			spin_lock(chip->mutex);
173 		}
174 		if (chip->erase_suspended || chip->write_suspended)  {
175 			/* Suspend has occured while sleep: reset timeout */
176 			timeo = reset_timeo;
177 			chip->erase_suspended = chip->write_suspended = 0;
178 		}
179 	}
180 	/* check status for errors */
181 	if (dsr & DSR_ERR) {
182 		/* Clear DSR*/
183 		map_write(map, CMD(~(DSR_ERR)), map->pfow_base + PFOW_DSR);
184 		printk(KERN_WARNING"%s: Bad status on wait: 0x%x \n",
185 				map->name, dsr);
186 		print_drs_error(dsr);
187 		ret = -EIO;
188 	}
189 	chip->state = FL_READY;
190 	return ret;
191 }
192 
193 static int get_chip(struct map_info *map, struct flchip *chip, int mode)
194 {
195 	int ret;
196 	DECLARE_WAITQUEUE(wait, current);
197 
198  retry:
199 	if (chip->priv && (mode == FL_WRITING || mode == FL_ERASING)
200 		&& chip->state != FL_SYNCING) {
201 		/*
202 		 * OK. We have possibility for contension on the write/erase
203 		 * operations which are global to the real chip and not per
204 		 * partition.  So let's fight it over in the partition which
205 		 * currently has authority on the operation.
206 		 *
207 		 * The rules are as follows:
208 		 *
209 		 * - any write operation must own shared->writing.
210 		 *
211 		 * - any erase operation must own _both_ shared->writing and
212 		 *   shared->erasing.
213 		 *
214 		 * - contension arbitration is handled in the owner's context.
215 		 *
216 		 * The 'shared' struct can be read and/or written only when
217 		 * its lock is taken.
218 		 */
219 		struct flchip_shared *shared = chip->priv;
220 		struct flchip *contender;
221 		spin_lock(&shared->lock);
222 		contender = shared->writing;
223 		if (contender && contender != chip) {
224 			/*
225 			 * The engine to perform desired operation on this
226 			 * partition is already in use by someone else.
227 			 * Let's fight over it in the context of the chip
228 			 * currently using it.  If it is possible to suspend,
229 			 * that other partition will do just that, otherwise
230 			 * it'll happily send us to sleep.  In any case, when
231 			 * get_chip returns success we're clear to go ahead.
232 			 */
233 			ret = spin_trylock(contender->mutex);
234 			spin_unlock(&shared->lock);
235 			if (!ret)
236 				goto retry;
237 			spin_unlock(chip->mutex);
238 			ret = chip_ready(map, contender, mode);
239 			spin_lock(chip->mutex);
240 
241 			if (ret == -EAGAIN) {
242 				spin_unlock(contender->mutex);
243 				goto retry;
244 			}
245 			if (ret) {
246 				spin_unlock(contender->mutex);
247 				return ret;
248 			}
249 			spin_lock(&shared->lock);
250 
251 			/* We should not own chip if it is already in FL_SYNCING
252 			 * state. Put contender and retry. */
253 			if (chip->state == FL_SYNCING) {
254 				put_chip(map, contender);
255 				spin_unlock(contender->mutex);
256 				goto retry;
257 			}
258 			spin_unlock(contender->mutex);
259 		}
260 
261 		/* Check if we have suspended erase on this chip.
262 		   Must sleep in such a case. */
263 		if (mode == FL_ERASING && shared->erasing
264 		    && shared->erasing->oldstate == FL_ERASING) {
265 			spin_unlock(&shared->lock);
266 			set_current_state(TASK_UNINTERRUPTIBLE);
267 			add_wait_queue(&chip->wq, &wait);
268 			spin_unlock(chip->mutex);
269 			schedule();
270 			remove_wait_queue(&chip->wq, &wait);
271 			spin_lock(chip->mutex);
272 			goto retry;
273 		}
274 
275 		/* We now own it */
276 		shared->writing = chip;
277 		if (mode == FL_ERASING)
278 			shared->erasing = chip;
279 		spin_unlock(&shared->lock);
280 	}
281 
282 	ret = chip_ready(map, chip, mode);
283 	if (ret == -EAGAIN)
284 		goto retry;
285 
286 	return ret;
287 }
288 
289 static int chip_ready(struct map_info *map, struct flchip *chip, int mode)
290 {
291 	struct lpddr_private *lpddr = map->fldrv_priv;
292 	int ret = 0;
293 	DECLARE_WAITQUEUE(wait, current);
294 
295 	/* Prevent setting state FL_SYNCING for chip in suspended state. */
296 	if (FL_SYNCING == mode && FL_READY != chip->oldstate)
297 		goto sleep;
298 
299 	switch (chip->state) {
300 	case FL_READY:
301 	case FL_JEDEC_QUERY:
302 		return 0;
303 
304 	case FL_ERASING:
305 		if (!lpddr->qinfo->SuspEraseSupp ||
306 			!(mode == FL_READY || mode == FL_POINT))
307 			goto sleep;
308 
309 		map_write(map, CMD(LPDDR_SUSPEND),
310 			map->pfow_base + PFOW_PROGRAM_ERASE_SUSPEND);
311 		chip->oldstate = FL_ERASING;
312 		chip->state = FL_ERASE_SUSPENDING;
313 		ret = wait_for_ready(map, chip, 0);
314 		if (ret) {
315 			/* Oops. something got wrong. */
316 			/* Resume and pretend we weren't here.  */
317 			map_write(map, CMD(LPDDR_RESUME),
318 				map->pfow_base + PFOW_COMMAND_CODE);
319 			map_write(map, CMD(LPDDR_START_EXECUTION),
320 				map->pfow_base + PFOW_COMMAND_EXECUTE);
321 			chip->state = FL_ERASING;
322 			chip->oldstate = FL_READY;
323 			printk(KERN_ERR "%s: suspend operation failed."
324 					"State may be wrong \n", map->name);
325 			return -EIO;
326 		}
327 		chip->erase_suspended = 1;
328 		chip->state = FL_READY;
329 		return 0;
330 		/* Erase suspend */
331 	case FL_POINT:
332 		/* Only if there's no operation suspended... */
333 		if (mode == FL_READY && chip->oldstate == FL_READY)
334 			return 0;
335 
336 	default:
337 sleep:
338 		set_current_state(TASK_UNINTERRUPTIBLE);
339 		add_wait_queue(&chip->wq, &wait);
340 		spin_unlock(chip->mutex);
341 		schedule();
342 		remove_wait_queue(&chip->wq, &wait);
343 		spin_lock(chip->mutex);
344 		return -EAGAIN;
345 	}
346 }
347 
348 static void put_chip(struct map_info *map, struct flchip *chip)
349 {
350 	if (chip->priv) {
351 		struct flchip_shared *shared = chip->priv;
352 		spin_lock(&shared->lock);
353 		if (shared->writing == chip && chip->oldstate == FL_READY) {
354 			/* We own the ability to write, but we're done */
355 			shared->writing = shared->erasing;
356 			if (shared->writing && shared->writing != chip) {
357 				/* give back the ownership */
358 				struct flchip *loaner = shared->writing;
359 				spin_lock(loaner->mutex);
360 				spin_unlock(&shared->lock);
361 				spin_unlock(chip->mutex);
362 				put_chip(map, loaner);
363 				spin_lock(chip->mutex);
364 				spin_unlock(loaner->mutex);
365 				wake_up(&chip->wq);
366 				return;
367 			}
368 			shared->erasing = NULL;
369 			shared->writing = NULL;
370 		} else if (shared->erasing == chip && shared->writing != chip) {
371 			/*
372 			 * We own the ability to erase without the ability
373 			 * to write, which means the erase was suspended
374 			 * and some other partition is currently writing.
375 			 * Don't let the switch below mess things up since
376 			 * we don't have ownership to resume anything.
377 			 */
378 			spin_unlock(&shared->lock);
379 			wake_up(&chip->wq);
380 			return;
381 		}
382 		spin_unlock(&shared->lock);
383 	}
384 
385 	switch (chip->oldstate) {
386 	case FL_ERASING:
387 		chip->state = chip->oldstate;
388 		map_write(map, CMD(LPDDR_RESUME),
389 				map->pfow_base + PFOW_COMMAND_CODE);
390 		map_write(map, CMD(LPDDR_START_EXECUTION),
391 				map->pfow_base + PFOW_COMMAND_EXECUTE);
392 		chip->oldstate = FL_READY;
393 		chip->state = FL_ERASING;
394 		break;
395 	case FL_READY:
396 		break;
397 	default:
398 		printk(KERN_ERR "%s: put_chip() called with oldstate %d!\n",
399 				map->name, chip->oldstate);
400 	}
401 	wake_up(&chip->wq);
402 }
403 
404 int do_write_buffer(struct map_info *map, struct flchip *chip,
405 			unsigned long adr, const struct kvec **pvec,
406 			unsigned long *pvec_seek, int len)
407 {
408 	struct lpddr_private *lpddr = map->fldrv_priv;
409 	map_word datum;
410 	int ret, wbufsize, word_gap, words;
411 	const struct kvec *vec;
412 	unsigned long vec_seek;
413 	unsigned long prog_buf_ofs;
414 
415 	wbufsize = 1 << lpddr->qinfo->BufSizeShift;
416 
417 	spin_lock(chip->mutex);
418 	ret = get_chip(map, chip, FL_WRITING);
419 	if (ret) {
420 		spin_unlock(chip->mutex);
421 		return ret;
422 	}
423 	/* Figure out the number of words to write */
424 	word_gap = (-adr & (map_bankwidth(map)-1));
425 	words = (len - word_gap + map_bankwidth(map) - 1) / map_bankwidth(map);
426 	if (!word_gap) {
427 		words--;
428 	} else {
429 		word_gap = map_bankwidth(map) - word_gap;
430 		adr -= word_gap;
431 		datum = map_word_ff(map);
432 	}
433 	/* Write data */
434 	/* Get the program buffer offset from PFOW register data first*/
435 	prog_buf_ofs = map->pfow_base + CMDVAL(map_read(map,
436 				map->pfow_base + PFOW_PROGRAM_BUFFER_OFFSET));
437 	vec = *pvec;
438 	vec_seek = *pvec_seek;
439 	do {
440 		int n = map_bankwidth(map) - word_gap;
441 
442 		if (n > vec->iov_len - vec_seek)
443 			n = vec->iov_len - vec_seek;
444 		if (n > len)
445 			n = len;
446 
447 		if (!word_gap && (len < map_bankwidth(map)))
448 			datum = map_word_ff(map);
449 
450 		datum = map_word_load_partial(map, datum,
451 				vec->iov_base + vec_seek, word_gap, n);
452 
453 		len -= n;
454 		word_gap += n;
455 		if (!len || word_gap == map_bankwidth(map)) {
456 			map_write(map, datum, prog_buf_ofs);
457 			prog_buf_ofs += map_bankwidth(map);
458 			word_gap = 0;
459 		}
460 
461 		vec_seek += n;
462 		if (vec_seek == vec->iov_len) {
463 			vec++;
464 			vec_seek = 0;
465 		}
466 	} while (len);
467 	*pvec = vec;
468 	*pvec_seek = vec_seek;
469 
470 	/* GO GO GO */
471 	send_pfow_command(map, LPDDR_BUFF_PROGRAM, adr, wbufsize, NULL);
472 	chip->state = FL_WRITING;
473 	ret = wait_for_ready(map, chip, (1<<lpddr->qinfo->ProgBufferTime));
474 	if (ret)	{
475 		printk(KERN_WARNING"%s Buffer program error: %d at %lx; \n",
476 			map->name, ret, adr);
477 		goto out;
478 	}
479 
480  out:	put_chip(map, chip);
481 	spin_unlock(chip->mutex);
482 	return ret;
483 }
484 
485 int do_erase_oneblock(struct mtd_info *mtd, loff_t adr)
486 {
487 	struct map_info *map = mtd->priv;
488 	struct lpddr_private *lpddr = map->fldrv_priv;
489 	int chipnum = adr >> lpddr->chipshift;
490 	struct flchip *chip = &lpddr->chips[chipnum];
491 	int ret;
492 
493 	spin_lock(chip->mutex);
494 	ret = get_chip(map, chip, FL_ERASING);
495 	if (ret) {
496 		spin_unlock(chip->mutex);
497 		return ret;
498 	}
499 	send_pfow_command(map, LPDDR_BLOCK_ERASE, adr, 0, NULL);
500 	chip->state = FL_ERASING;
501 	ret = wait_for_ready(map, chip, (1<<lpddr->qinfo->BlockEraseTime)*1000);
502 	if (ret) {
503 		printk(KERN_WARNING"%s Erase block error %d at : %llx\n",
504 			map->name, ret, adr);
505 		goto out;
506 	}
507  out:	put_chip(map, chip);
508 	spin_unlock(chip->mutex);
509 	return ret;
510 }
511 
512 static int lpddr_read(struct mtd_info *mtd, loff_t adr, size_t len,
513 			size_t *retlen, u_char *buf)
514 {
515 	struct map_info *map = mtd->priv;
516 	struct lpddr_private *lpddr = map->fldrv_priv;
517 	int chipnum = adr >> lpddr->chipshift;
518 	struct flchip *chip = &lpddr->chips[chipnum];
519 	int ret = 0;
520 
521 	spin_lock(chip->mutex);
522 	ret = get_chip(map, chip, FL_READY);
523 	if (ret) {
524 		spin_unlock(chip->mutex);
525 		return ret;
526 	}
527 
528 	map_copy_from(map, buf, adr, len);
529 	*retlen = len;
530 
531 	put_chip(map, chip);
532 	spin_unlock(chip->mutex);
533 	return ret;
534 }
535 
536 static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
537 			size_t *retlen, void **mtdbuf, resource_size_t *phys)
538 {
539 	struct map_info *map = mtd->priv;
540 	struct lpddr_private *lpddr = map->fldrv_priv;
541 	int chipnum = adr >> lpddr->chipshift;
542 	unsigned long ofs, last_end = 0;
543 	struct flchip *chip = &lpddr->chips[chipnum];
544 	int ret = 0;
545 
546 	if (!map->virt || (adr + len > mtd->size))
547 		return -EINVAL;
548 
549 	/* ofs: offset within the first chip that the first read should start */
550 	ofs = adr - (chipnum << lpddr->chipshift);
551 
552 	*mtdbuf = (void *)map->virt + chip->start + ofs;
553 	*retlen = 0;
554 
555 	while (len) {
556 		unsigned long thislen;
557 
558 		if (chipnum >= lpddr->numchips)
559 			break;
560 
561 		/* We cannot point across chips that are virtually disjoint */
562 		if (!last_end)
563 			last_end = chip->start;
564 		else if (chip->start != last_end)
565 			break;
566 
567 		if ((len + ofs - 1) >> lpddr->chipshift)
568 			thislen = (1<<lpddr->chipshift) - ofs;
569 		else
570 			thislen = len;
571 		/* get the chip */
572 		spin_lock(chip->mutex);
573 		ret = get_chip(map, chip, FL_POINT);
574 		spin_unlock(chip->mutex);
575 		if (ret)
576 			break;
577 
578 		chip->state = FL_POINT;
579 		chip->ref_point_counter++;
580 		*retlen += thislen;
581 		len -= thislen;
582 
583 		ofs = 0;
584 		last_end += 1 << lpddr->chipshift;
585 		chipnum++;
586 		chip = &lpddr->chips[chipnum];
587 	}
588 	return 0;
589 }
590 
591 static void lpddr_unpoint (struct mtd_info *mtd, loff_t adr, size_t len)
592 {
593 	struct map_info *map = mtd->priv;
594 	struct lpddr_private *lpddr = map->fldrv_priv;
595 	int chipnum = adr >> lpddr->chipshift;
596 	unsigned long ofs;
597 
598 	/* ofs: offset within the first chip that the first read should start */
599 	ofs = adr - (chipnum << lpddr->chipshift);
600 
601 	while (len) {
602 		unsigned long thislen;
603 		struct flchip *chip;
604 
605 		chip = &lpddr->chips[chipnum];
606 		if (chipnum >= lpddr->numchips)
607 			break;
608 
609 		if ((len + ofs - 1) >> lpddr->chipshift)
610 			thislen = (1<<lpddr->chipshift) - ofs;
611 		else
612 			thislen = len;
613 
614 		spin_lock(chip->mutex);
615 		if (chip->state == FL_POINT) {
616 			chip->ref_point_counter--;
617 			if (chip->ref_point_counter == 0)
618 				chip->state = FL_READY;
619 		} else
620 			printk(KERN_WARNING "%s: Warning: unpoint called on non"
621 					"pointed region\n", map->name);
622 
623 		put_chip(map, chip);
624 		spin_unlock(chip->mutex);
625 
626 		len -= thislen;
627 		ofs = 0;
628 		chipnum++;
629 	}
630 }
631 
632 static int lpddr_write_buffers(struct mtd_info *mtd, loff_t to, size_t len,
633 				size_t *retlen, const u_char *buf)
634 {
635 	struct kvec vec;
636 
637 	vec.iov_base = (void *) buf;
638 	vec.iov_len = len;
639 
640 	return lpddr_writev(mtd, &vec, 1, to, retlen);
641 }
642 
643 
644 static int lpddr_writev(struct mtd_info *mtd, const struct kvec *vecs,
645 				unsigned long count, loff_t to, size_t *retlen)
646 {
647 	struct map_info *map = mtd->priv;
648 	struct lpddr_private *lpddr = map->fldrv_priv;
649 	int ret = 0;
650 	int chipnum;
651 	unsigned long ofs, vec_seek, i;
652 	int wbufsize = 1 << lpddr->qinfo->BufSizeShift;
653 
654 	size_t len = 0;
655 
656 	for (i = 0; i < count; i++)
657 		len += vecs[i].iov_len;
658 
659 	*retlen = 0;
660 	if (!len)
661 		return 0;
662 
663 	chipnum = to >> lpddr->chipshift;
664 
665 	ofs = to;
666 	vec_seek = 0;
667 
668 	do {
669 		/* We must not cross write block boundaries */
670 		int size = wbufsize - (ofs & (wbufsize-1));
671 
672 		if (size > len)
673 			size = len;
674 
675 		ret = do_write_buffer(map, &lpddr->chips[chipnum],
676 					  ofs, &vecs, &vec_seek, size);
677 		if (ret)
678 			return ret;
679 
680 		ofs += size;
681 		(*retlen) += size;
682 		len -= size;
683 
684 		/* Be nice and reschedule with the chip in a usable
685 		 * state for other processes */
686 		cond_resched();
687 
688 	} while (len);
689 
690 	return 0;
691 }
692 
693 static int lpddr_erase(struct mtd_info *mtd, struct erase_info *instr)
694 {
695 	unsigned long ofs, len;
696 	int ret;
697 	struct map_info *map = mtd->priv;
698 	struct lpddr_private *lpddr = map->fldrv_priv;
699 	int size = 1 << lpddr->qinfo->UniformBlockSizeShift;
700 
701 	ofs = instr->addr;
702 	len = instr->len;
703 
704 	if (ofs > mtd->size || (len + ofs) > mtd->size)
705 		return -EINVAL;
706 
707 	while (len > 0) {
708 		ret = do_erase_oneblock(mtd, ofs);
709 		if (ret)
710 			return ret;
711 		ofs += size;
712 		len -= size;
713 	}
714 	instr->state = MTD_ERASE_DONE;
715 	mtd_erase_callback(instr);
716 
717 	return 0;
718 }
719 
720 #define DO_XXLOCK_LOCK		1
721 #define DO_XXLOCK_UNLOCK	2
722 int do_xxlock(struct mtd_info *mtd, loff_t adr, uint32_t len, int thunk)
723 {
724 	int ret = 0;
725 	struct map_info *map = mtd->priv;
726 	struct lpddr_private *lpddr = map->fldrv_priv;
727 	int chipnum = adr >> lpddr->chipshift;
728 	struct flchip *chip = &lpddr->chips[chipnum];
729 
730 	spin_lock(chip->mutex);
731 	ret = get_chip(map, chip, FL_LOCKING);
732 	if (ret) {
733 		spin_unlock(chip->mutex);
734 		return ret;
735 	}
736 
737 	if (thunk == DO_XXLOCK_LOCK) {
738 		send_pfow_command(map, LPDDR_LOCK_BLOCK, adr, adr + len, NULL);
739 		chip->state = FL_LOCKING;
740 	} else if (thunk == DO_XXLOCK_UNLOCK) {
741 		send_pfow_command(map, LPDDR_UNLOCK_BLOCK, adr, adr + len, NULL);
742 		chip->state = FL_UNLOCKING;
743 	} else
744 		BUG();
745 
746 	ret = wait_for_ready(map, chip, 1);
747 	if (ret)	{
748 		printk(KERN_ERR "%s: block unlock error status %d \n",
749 				map->name, ret);
750 		goto out;
751 	}
752 out:	put_chip(map, chip);
753 	spin_unlock(chip->mutex);
754 	return ret;
755 }
756 
757 static int lpddr_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
758 {
759 	return do_xxlock(mtd, ofs, len, DO_XXLOCK_LOCK);
760 }
761 
762 static int lpddr_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
763 {
764 	return do_xxlock(mtd, ofs, len, DO_XXLOCK_UNLOCK);
765 }
766 
767 int word_program(struct map_info *map, loff_t adr, uint32_t curval)
768 {
769     int ret;
770 	struct lpddr_private *lpddr = map->fldrv_priv;
771 	int chipnum = adr >> lpddr->chipshift;
772 	struct flchip *chip = &lpddr->chips[chipnum];
773 
774 	spin_lock(chip->mutex);
775 	ret = get_chip(map, chip, FL_WRITING);
776 	if (ret) {
777 		spin_unlock(chip->mutex);
778 		return ret;
779 	}
780 
781 	send_pfow_command(map, LPDDR_WORD_PROGRAM, adr, 0x00, (map_word *)&curval);
782 
783 	ret = wait_for_ready(map, chip, (1<<lpddr->qinfo->SingleWordProgTime));
784 	if (ret)	{
785 		printk(KERN_WARNING"%s word_program error at: %llx; val: %x\n",
786 			map->name, adr, curval);
787 		goto out;
788 	}
789 
790 out:	put_chip(map, chip);
791 	spin_unlock(chip->mutex);
792 	return ret;
793 }
794 
795 MODULE_LICENSE("GPL");
796 MODULE_AUTHOR("Alexey Korolev <akorolev@infradead.org>");
797 MODULE_DESCRIPTION("MTD driver for LPDDR flash chips");
798