Merge tag '6.10-rc-smb-fix' of git://git.samba.org/sfrench/cifs-2.6
[sfrench/cifs-2.6.git] / drivers / mtd / lpddr / lpddr_cmds.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * LPDDR flash memory device operations. This module provides read, write,
4  * erase, lock/unlock support for LPDDR flash memories
5  * (C) 2008 Korolev Alexey <akorolev@infradead.org>
6  * (C) 2008 Vasiliy Leonenko <vasiliy.leonenko@gmail.com>
7  * Many thanks to Roman Borisov for initial enabling
8  *
9  * TODO:
10  * Implement VPP management
11  * Implement XIP support
12  * Implement OTP support
13  */
14 #include <linux/mtd/pfow.h>
15 #include <linux/mtd/qinfo.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18
19 static int lpddr_read(struct mtd_info *mtd, loff_t adr, size_t len,
20                                         size_t *retlen, u_char *buf);
21 static int lpddr_write_buffers(struct mtd_info *mtd, loff_t to,
22                                 size_t len, size_t *retlen, const u_char *buf);
23 static int lpddr_writev(struct mtd_info *mtd, const struct kvec *vecs,
24                                 unsigned long count, loff_t to, size_t *retlen);
25 static int lpddr_erase(struct mtd_info *mtd, struct erase_info *instr);
26 static int lpddr_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
27 static int lpddr_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
28 static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
29                         size_t *retlen, void **mtdbuf, resource_size_t *phys);
30 static int lpddr_unpoint(struct mtd_info *mtd, loff_t adr, size_t len);
31 static int get_chip(struct map_info *map, struct flchip *chip, int mode);
32 static int chip_ready(struct map_info *map, struct flchip *chip, int mode);
33 static void put_chip(struct map_info *map, struct flchip *chip);
34
35 struct mtd_info *lpddr_cmdset(struct map_info *map)
36 {
37         struct lpddr_private *lpddr = map->fldrv_priv;
38         struct flchip_shared *shared;
39         struct flchip *chip;
40         struct mtd_info *mtd;
41         int numchips;
42         int i, j;
43
44         mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
45         if (!mtd)
46                 return NULL;
47         mtd->priv = map;
48         mtd->type = MTD_NORFLASH;
49
50         /* Fill in the default mtd operations */
51         mtd->_read = lpddr_read;
52         mtd->type = MTD_NORFLASH;
53         mtd->flags = MTD_CAP_NORFLASH;
54         mtd->flags &= ~MTD_BIT_WRITEABLE;
55         mtd->_erase = lpddr_erase;
56         mtd->_write = lpddr_write_buffers;
57         mtd->_writev = lpddr_writev;
58         mtd->_lock = lpddr_lock;
59         mtd->_unlock = lpddr_unlock;
60         if (map_is_linear(map)) {
61                 mtd->_point = lpddr_point;
62                 mtd->_unpoint = lpddr_unpoint;
63         }
64         mtd->size = 1ULL << lpddr->qinfo->DevSizeShift;
65         mtd->erasesize = 1 << lpddr->qinfo->UniformBlockSizeShift;
66         mtd->writesize = 1 << lpddr->qinfo->BufSizeShift;
67
68         shared = kmalloc_array(lpddr->numchips, sizeof(struct flchip_shared),
69                                                 GFP_KERNEL);
70         if (!shared) {
71                 kfree(mtd);
72                 return NULL;
73         }
74
75         chip = &lpddr->chips[0];
76         numchips = lpddr->numchips / lpddr->qinfo->HWPartsNum;
77         for (i = 0; i < numchips; i++) {
78                 shared[i].writing = shared[i].erasing = NULL;
79                 mutex_init(&shared[i].lock);
80                 for (j = 0; j < lpddr->qinfo->HWPartsNum; j++) {
81                         *chip = lpddr->chips[i];
82                         chip->start += j << lpddr->chipshift;
83                         chip->oldstate = chip->state = FL_READY;
84                         chip->priv = &shared[i];
85                         /* those should be reset too since
86                            they create memory references. */
87                         init_waitqueue_head(&chip->wq);
88                         mutex_init(&chip->mutex);
89                         chip++;
90                 }
91         }
92
93         return mtd;
94 }
95 EXPORT_SYMBOL(lpddr_cmdset);
96
97 static void print_drs_error(unsigned int dsr)
98 {
99         int prog_status = (dsr & DSR_RPS) >> 8;
100
101         if (!(dsr & DSR_AVAILABLE))
102                 pr_notice("DSR.15: (0) Device not Available\n");
103         if ((prog_status & 0x03) == 0x03)
104                 pr_notice("DSR.9,8: (11) Attempt to program invalid half with 41h command\n");
105         else if (prog_status & 0x02)
106                 pr_notice("DSR.9,8: (10) Object Mode Program attempt in region with Control Mode data\n");
107         else if (prog_status &  0x01)
108                 pr_notice("DSR.9,8: (01) Program attempt in region with Object Mode data\n");
109         if (!(dsr & DSR_READY_STATUS))
110                 pr_notice("DSR.7: (0) Device is Busy\n");
111         if (dsr & DSR_ESS)
112                 pr_notice("DSR.6: (1) Erase Suspended\n");
113         if (dsr & DSR_ERASE_STATUS)
114                 pr_notice("DSR.5: (1) Erase/Blank check error\n");
115         if (dsr & DSR_PROGRAM_STATUS)
116                 pr_notice("DSR.4: (1) Program Error\n");
117         if (dsr & DSR_VPPS)
118                 pr_notice("DSR.3: (1) Vpp low detect, operation aborted\n");
119         if (dsr & DSR_PSS)
120                 pr_notice("DSR.2: (1) Program suspended\n");
121         if (dsr & DSR_DPS)
122                 pr_notice("DSR.1: (1) Aborted Erase/Program attempt on locked block\n");
123 }
124
125 static int wait_for_ready(struct map_info *map, struct flchip *chip,
126                 unsigned int chip_op_time)
127 {
128         unsigned int timeo, reset_timeo, sleep_time;
129         unsigned int dsr;
130         flstate_t chip_state = chip->state;
131         int ret = 0;
132
133         /* set our timeout to 8 times the expected delay */
134         timeo = chip_op_time * 8;
135         if (!timeo)
136                 timeo = 500000;
137         reset_timeo = timeo;
138         sleep_time = chip_op_time / 2;
139
140         for (;;) {
141                 dsr = CMDVAL(map_read(map, map->pfow_base + PFOW_DSR));
142                 if (dsr & DSR_READY_STATUS)
143                         break;
144                 if (!timeo) {
145                         printk(KERN_ERR "%s: Flash timeout error state %d \n",
146                                                         map->name, chip_state);
147                         ret = -ETIME;
148                         break;
149                 }
150
151                 /* OK Still waiting. Drop the lock, wait a while and retry. */
152                 mutex_unlock(&chip->mutex);
153                 if (sleep_time >= 1000000/HZ) {
154                         /*
155                          * Half of the normal delay still remaining
156                          * can be performed with a sleeping delay instead
157                          * of busy waiting.
158                          */
159                         msleep(sleep_time/1000);
160                         timeo -= sleep_time;
161                         sleep_time = 1000000/HZ;
162                 } else {
163                         udelay(1);
164                         cond_resched();
165                         timeo--;
166                 }
167                 mutex_lock(&chip->mutex);
168
169                 while (chip->state != chip_state) {
170                         /* Someone's suspended the operation: sleep */
171                         DECLARE_WAITQUEUE(wait, current);
172                         set_current_state(TASK_UNINTERRUPTIBLE);
173                         add_wait_queue(&chip->wq, &wait);
174                         mutex_unlock(&chip->mutex);
175                         schedule();
176                         remove_wait_queue(&chip->wq, &wait);
177                         mutex_lock(&chip->mutex);
178                 }
179                 if (chip->erase_suspended || chip->write_suspended)  {
180                         /* Suspend has occurred while sleep: reset timeout */
181                         timeo = reset_timeo;
182                         chip->erase_suspended = chip->write_suspended = 0;
183                 }
184         }
185         /* check status for errors */
186         if (dsr & DSR_ERR) {
187                 /* Clear DSR*/
188                 map_write(map, CMD(~(DSR_ERR)), map->pfow_base + PFOW_DSR);
189                 printk(KERN_WARNING"%s: Bad status on wait: 0x%x \n",
190                                 map->name, dsr);
191                 print_drs_error(dsr);
192                 ret = -EIO;
193         }
194         chip->state = FL_READY;
195         return ret;
196 }
197
198 static int get_chip(struct map_info *map, struct flchip *chip, int mode)
199 {
200         int ret;
201         DECLARE_WAITQUEUE(wait, current);
202
203  retry:
204         if (chip->priv && (mode == FL_WRITING || mode == FL_ERASING)
205                 && chip->state != FL_SYNCING) {
206                 /*
207                  * OK. We have possibility for contension on the write/erase
208                  * operations which are global to the real chip and not per
209                  * partition.  So let's fight it over in the partition which
210                  * currently has authority on the operation.
211                  *
212                  * The rules are as follows:
213                  *
214                  * - any write operation must own shared->writing.
215                  *
216                  * - any erase operation must own _both_ shared->writing and
217                  *   shared->erasing.
218                  *
219                  * - contension arbitration is handled in the owner's context.
220                  *
221                  * The 'shared' struct can be read and/or written only when
222                  * its lock is taken.
223                  */
224                 struct flchip_shared *shared = chip->priv;
225                 struct flchip *contender;
226                 mutex_lock(&shared->lock);
227                 contender = shared->writing;
228                 if (contender && contender != chip) {
229                         /*
230                          * The engine to perform desired operation on this
231                          * partition is already in use by someone else.
232                          * Let's fight over it in the context of the chip
233                          * currently using it.  If it is possible to suspend,
234                          * that other partition will do just that, otherwise
235                          * it'll happily send us to sleep.  In any case, when
236                          * get_chip returns success we're clear to go ahead.
237                          */
238                         ret = mutex_trylock(&contender->mutex);
239                         mutex_unlock(&shared->lock);
240                         if (!ret)
241                                 goto retry;
242                         mutex_unlock(&chip->mutex);
243                         ret = chip_ready(map, contender, mode);
244                         mutex_lock(&chip->mutex);
245
246                         if (ret == -EAGAIN) {
247                                 mutex_unlock(&contender->mutex);
248                                 goto retry;
249                         }
250                         if (ret) {
251                                 mutex_unlock(&contender->mutex);
252                                 return ret;
253                         }
254                         mutex_lock(&shared->lock);
255
256                         /* We should not own chip if it is already in FL_SYNCING
257                          * state. Put contender and retry. */
258                         if (chip->state == FL_SYNCING) {
259                                 put_chip(map, contender);
260                                 mutex_unlock(&contender->mutex);
261                                 goto retry;
262                         }
263                         mutex_unlock(&contender->mutex);
264                 }
265
266                 /* Check if we have suspended erase on this chip.
267                    Must sleep in such a case. */
268                 if (mode == FL_ERASING && shared->erasing
269                     && shared->erasing->oldstate == FL_ERASING) {
270                         mutex_unlock(&shared->lock);
271                         set_current_state(TASK_UNINTERRUPTIBLE);
272                         add_wait_queue(&chip->wq, &wait);
273                         mutex_unlock(&chip->mutex);
274                         schedule();
275                         remove_wait_queue(&chip->wq, &wait);
276                         mutex_lock(&chip->mutex);
277                         goto retry;
278                 }
279
280                 /* We now own it */
281                 shared->writing = chip;
282                 if (mode == FL_ERASING)
283                         shared->erasing = chip;
284                 mutex_unlock(&shared->lock);
285         }
286
287         ret = chip_ready(map, chip, mode);
288         if (ret == -EAGAIN)
289                 goto retry;
290
291         return ret;
292 }
293
294 static int chip_ready(struct map_info *map, struct flchip *chip, int mode)
295 {
296         struct lpddr_private *lpddr = map->fldrv_priv;
297         int ret = 0;
298         DECLARE_WAITQUEUE(wait, current);
299
300         /* Prevent setting state FL_SYNCING for chip in suspended state. */
301         if (FL_SYNCING == mode && FL_READY != chip->oldstate)
302                 goto sleep;
303
304         switch (chip->state) {
305         case FL_READY:
306         case FL_JEDEC_QUERY:
307                 return 0;
308
309         case FL_ERASING:
310                 if (!lpddr->qinfo->SuspEraseSupp ||
311                         !(mode == FL_READY || mode == FL_POINT))
312                         goto sleep;
313
314                 map_write(map, CMD(LPDDR_SUSPEND),
315                         map->pfow_base + PFOW_PROGRAM_ERASE_SUSPEND);
316                 chip->oldstate = FL_ERASING;
317                 chip->state = FL_ERASE_SUSPENDING;
318                 ret = wait_for_ready(map, chip, 0);
319                 if (ret) {
320                         /* Oops. something got wrong. */
321                         /* Resume and pretend we weren't here.  */
322                         put_chip(map, chip);
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                 fallthrough;
336         default:
337 sleep:
338                 set_current_state(TASK_UNINTERRUPTIBLE);
339                 add_wait_queue(&chip->wq, &wait);
340                 mutex_unlock(&chip->mutex);
341                 schedule();
342                 remove_wait_queue(&chip->wq, &wait);
343                 mutex_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                 mutex_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                                 mutex_lock(&loaner->mutex);
360                                 mutex_unlock(&shared->lock);
361                                 mutex_unlock(&chip->mutex);
362                                 put_chip(map, loaner);
363                                 mutex_lock(&chip->mutex);
364                                 mutex_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                         mutex_unlock(&shared->lock);
379                         wake_up(&chip->wq);
380                         return;
381                 }
382                 mutex_unlock(&shared->lock);
383         }
384
385         switch (chip->oldstate) {
386         case FL_ERASING:
387                 map_write(map, CMD(LPDDR_RESUME),
388                                 map->pfow_base + PFOW_COMMAND_CODE);
389                 map_write(map, CMD(LPDDR_START_EXECUTION),
390                                 map->pfow_base + PFOW_COMMAND_EXECUTE);
391                 chip->oldstate = FL_READY;
392                 chip->state = FL_ERASING;
393                 break;
394         case FL_READY:
395                 break;
396         default:
397                 printk(KERN_ERR "%s: put_chip() called with oldstate %d!\n",
398                                 map->name, chip->oldstate);
399         }
400         wake_up(&chip->wq);
401 }
402
403 static int do_write_buffer(struct map_info *map, struct flchip *chip,
404                         unsigned long adr, const struct kvec **pvec,
405                         unsigned long *pvec_seek, int len)
406 {
407         struct lpddr_private *lpddr = map->fldrv_priv;
408         map_word datum;
409         int ret, wbufsize, word_gap;
410         const struct kvec *vec;
411         unsigned long vec_seek;
412         unsigned long prog_buf_ofs;
413
414         wbufsize = 1 << lpddr->qinfo->BufSizeShift;
415
416         mutex_lock(&chip->mutex);
417         ret = get_chip(map, chip, FL_WRITING);
418         if (ret) {
419                 mutex_unlock(&chip->mutex);
420                 return ret;
421         }
422         /* Figure out the number of words to write */
423         word_gap = (-adr & (map_bankwidth(map)-1));
424         if (word_gap) {
425                 word_gap = map_bankwidth(map) - word_gap;
426                 adr -= word_gap;
427                 datum = map_word_ff(map);
428         }
429         /* Write data */
430         /* Get the program buffer offset from PFOW register data first*/
431         prog_buf_ofs = map->pfow_base + CMDVAL(map_read(map,
432                                 map->pfow_base + PFOW_PROGRAM_BUFFER_OFFSET));
433         vec = *pvec;
434         vec_seek = *pvec_seek;
435         do {
436                 int n = map_bankwidth(map) - word_gap;
437
438                 if (n > vec->iov_len - vec_seek)
439                         n = vec->iov_len - vec_seek;
440                 if (n > len)
441                         n = len;
442
443                 if (!word_gap && (len < map_bankwidth(map)))
444                         datum = map_word_ff(map);
445
446                 datum = map_word_load_partial(map, datum,
447                                 vec->iov_base + vec_seek, word_gap, n);
448
449                 len -= n;
450                 word_gap += n;
451                 if (!len || word_gap == map_bankwidth(map)) {
452                         map_write(map, datum, prog_buf_ofs);
453                         prog_buf_ofs += map_bankwidth(map);
454                         word_gap = 0;
455                 }
456
457                 vec_seek += n;
458                 if (vec_seek == vec->iov_len) {
459                         vec++;
460                         vec_seek = 0;
461                 }
462         } while (len);
463         *pvec = vec;
464         *pvec_seek = vec_seek;
465
466         /* GO GO GO */
467         send_pfow_command(map, LPDDR_BUFF_PROGRAM, adr, wbufsize, NULL);
468         chip->state = FL_WRITING;
469         ret = wait_for_ready(map, chip, (1<<lpddr->qinfo->ProgBufferTime));
470         if (ret)        {
471                 printk(KERN_WARNING"%s Buffer program error: %d at %lx; \n",
472                         map->name, ret, adr);
473                 goto out;
474         }
475
476  out:   put_chip(map, chip);
477         mutex_unlock(&chip->mutex);
478         return ret;
479 }
480
481 static int do_erase_oneblock(struct mtd_info *mtd, loff_t adr)
482 {
483         struct map_info *map = mtd->priv;
484         struct lpddr_private *lpddr = map->fldrv_priv;
485         int chipnum = adr >> lpddr->chipshift;
486         struct flchip *chip = &lpddr->chips[chipnum];
487         int ret;
488
489         mutex_lock(&chip->mutex);
490         ret = get_chip(map, chip, FL_ERASING);
491         if (ret) {
492                 mutex_unlock(&chip->mutex);
493                 return ret;
494         }
495         send_pfow_command(map, LPDDR_BLOCK_ERASE, adr, 0, NULL);
496         chip->state = FL_ERASING;
497         ret = wait_for_ready(map, chip, (1<<lpddr->qinfo->BlockEraseTime)*1000);
498         if (ret) {
499                 printk(KERN_WARNING"%s Erase block error %d at : %llx\n",
500                         map->name, ret, adr);
501                 goto out;
502         }
503  out:   put_chip(map, chip);
504         mutex_unlock(&chip->mutex);
505         return ret;
506 }
507
508 static int lpddr_read(struct mtd_info *mtd, loff_t adr, size_t len,
509                         size_t *retlen, u_char *buf)
510 {
511         struct map_info *map = mtd->priv;
512         struct lpddr_private *lpddr = map->fldrv_priv;
513         int chipnum = adr >> lpddr->chipshift;
514         struct flchip *chip = &lpddr->chips[chipnum];
515         int ret = 0;
516
517         mutex_lock(&chip->mutex);
518         ret = get_chip(map, chip, FL_READY);
519         if (ret) {
520                 mutex_unlock(&chip->mutex);
521                 return ret;
522         }
523
524         map_copy_from(map, buf, adr, len);
525         *retlen = len;
526
527         put_chip(map, chip);
528         mutex_unlock(&chip->mutex);
529         return ret;
530 }
531
532 static int lpddr_point(struct mtd_info *mtd, loff_t adr, size_t len,
533                         size_t *retlen, void **mtdbuf, resource_size_t *phys)
534 {
535         struct map_info *map = mtd->priv;
536         struct lpddr_private *lpddr = map->fldrv_priv;
537         int chipnum = adr >> lpddr->chipshift;
538         unsigned long ofs, last_end = 0;
539         struct flchip *chip = &lpddr->chips[chipnum];
540         int ret = 0;
541
542         if (!map->virt)
543                 return -EINVAL;
544
545         /* ofs: offset within the first chip that the first read should start */
546         ofs = adr - (chipnum << lpddr->chipshift);
547         *mtdbuf = (void *)map->virt + chip->start + ofs;
548
549         while (len) {
550                 unsigned long thislen;
551
552                 if (chipnum >= lpddr->numchips)
553                         break;
554
555                 /* We cannot point across chips that are virtually disjoint */
556                 if (!last_end)
557                         last_end = chip->start;
558                 else if (chip->start != last_end)
559                         break;
560
561                 if ((len + ofs - 1) >> lpddr->chipshift)
562                         thislen = (1<<lpddr->chipshift) - ofs;
563                 else
564                         thislen = len;
565                 /* get the chip */
566                 mutex_lock(&chip->mutex);
567                 ret = get_chip(map, chip, FL_POINT);
568                 mutex_unlock(&chip->mutex);
569                 if (ret)
570                         break;
571
572                 chip->state = FL_POINT;
573                 chip->ref_point_counter++;
574                 *retlen += thislen;
575                 len -= thislen;
576
577                 ofs = 0;
578                 last_end += 1 << lpddr->chipshift;
579                 chipnum++;
580                 chip = &lpddr->chips[chipnum];
581         }
582         return 0;
583 }
584
585 static int lpddr_unpoint (struct mtd_info *mtd, loff_t adr, size_t len)
586 {
587         struct map_info *map = mtd->priv;
588         struct lpddr_private *lpddr = map->fldrv_priv;
589         int chipnum = adr >> lpddr->chipshift, err = 0;
590         unsigned long ofs;
591
592         /* ofs: offset within the first chip that the first read should start */
593         ofs = adr - (chipnum << lpddr->chipshift);
594
595         while (len) {
596                 unsigned long thislen;
597                 struct flchip *chip;
598
599                 chip = &lpddr->chips[chipnum];
600                 if (chipnum >= lpddr->numchips)
601                         break;
602
603                 if ((len + ofs - 1) >> lpddr->chipshift)
604                         thislen = (1<<lpddr->chipshift) - ofs;
605                 else
606                         thislen = len;
607
608                 mutex_lock(&chip->mutex);
609                 if (chip->state == FL_POINT) {
610                         chip->ref_point_counter--;
611                         if (chip->ref_point_counter == 0)
612                                 chip->state = FL_READY;
613                 } else {
614                         printk(KERN_WARNING "%s: Warning: unpoint called on non"
615                                         "pointed region\n", map->name);
616                         err = -EINVAL;
617                 }
618
619                 put_chip(map, chip);
620                 mutex_unlock(&chip->mutex);
621
622                 len -= thislen;
623                 ofs = 0;
624                 chipnum++;
625         }
626
627         return err;
628 }
629
630 static int lpddr_write_buffers(struct mtd_info *mtd, loff_t to, size_t len,
631                                 size_t *retlen, const u_char *buf)
632 {
633         struct kvec vec;
634
635         vec.iov_base = (void *) buf;
636         vec.iov_len = len;
637
638         return lpddr_writev(mtd, &vec, 1, to, retlen);
639 }
640
641
642 static int lpddr_writev(struct mtd_info *mtd, const struct kvec *vecs,
643                                 unsigned long count, loff_t to, size_t *retlen)
644 {
645         struct map_info *map = mtd->priv;
646         struct lpddr_private *lpddr = map->fldrv_priv;
647         int ret = 0;
648         int chipnum;
649         unsigned long ofs, vec_seek, i;
650         int wbufsize = 1 << lpddr->qinfo->BufSizeShift;
651         size_t len = 0;
652
653         for (i = 0; i < count; i++)
654                 len += vecs[i].iov_len;
655
656         if (!len)
657                 return 0;
658
659         chipnum = to >> lpddr->chipshift;
660
661         ofs = to;
662         vec_seek = 0;
663
664         do {
665                 /* We must not cross write block boundaries */
666                 int size = wbufsize - (ofs & (wbufsize-1));
667
668                 if (size > len)
669                         size = len;
670
671                 ret = do_write_buffer(map, &lpddr->chips[chipnum],
672                                           ofs, &vecs, &vec_seek, size);
673                 if (ret)
674                         return ret;
675
676                 ofs += size;
677                 (*retlen) += size;
678                 len -= size;
679
680                 /* Be nice and reschedule with the chip in a usable
681                  * state for other processes */
682                 cond_resched();
683
684         } while (len);
685
686         return 0;
687 }
688
689 static int lpddr_erase(struct mtd_info *mtd, struct erase_info *instr)
690 {
691         unsigned long ofs, len;
692         int ret;
693         struct map_info *map = mtd->priv;
694         struct lpddr_private *lpddr = map->fldrv_priv;
695         int size = 1 << lpddr->qinfo->UniformBlockSizeShift;
696
697         ofs = instr->addr;
698         len = instr->len;
699
700         while (len > 0) {
701                 ret = do_erase_oneblock(mtd, ofs);
702                 if (ret)
703                         return ret;
704                 ofs += size;
705                 len -= size;
706         }
707
708         return 0;
709 }
710
711 #define DO_XXLOCK_LOCK          1
712 #define DO_XXLOCK_UNLOCK        2
713 static int do_xxlock(struct mtd_info *mtd, loff_t adr, uint32_t len, int thunk)
714 {
715         int ret = 0;
716         struct map_info *map = mtd->priv;
717         struct lpddr_private *lpddr = map->fldrv_priv;
718         int chipnum = adr >> lpddr->chipshift;
719         struct flchip *chip = &lpddr->chips[chipnum];
720
721         mutex_lock(&chip->mutex);
722         ret = get_chip(map, chip, FL_LOCKING);
723         if (ret) {
724                 mutex_unlock(&chip->mutex);
725                 return ret;
726         }
727
728         if (thunk == DO_XXLOCK_LOCK) {
729                 send_pfow_command(map, LPDDR_LOCK_BLOCK, adr, adr + len, NULL);
730                 chip->state = FL_LOCKING;
731         } else if (thunk == DO_XXLOCK_UNLOCK) {
732                 send_pfow_command(map, LPDDR_UNLOCK_BLOCK, adr, adr + len, NULL);
733                 chip->state = FL_UNLOCKING;
734         } else
735                 BUG();
736
737         ret = wait_for_ready(map, chip, 1);
738         if (ret)        {
739                 printk(KERN_ERR "%s: block unlock error status %d \n",
740                                 map->name, ret);
741                 goto out;
742         }
743 out:    put_chip(map, chip);
744         mutex_unlock(&chip->mutex);
745         return ret;
746 }
747
748 static int lpddr_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
749 {
750         return do_xxlock(mtd, ofs, len, DO_XXLOCK_LOCK);
751 }
752
753 static int lpddr_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
754 {
755         return do_xxlock(mtd, ofs, len, DO_XXLOCK_UNLOCK);
756 }
757
758 MODULE_LICENSE("GPL");
759 MODULE_AUTHOR("Alexey Korolev <akorolev@infradead.org>");
760 MODULE_DESCRIPTION("MTD driver for LPDDR flash chips");