Merge tag 'for-linus-20130301' of git://git.infradead.org/linux-mtd
[linux-3.10.git] / drivers / mtd / nand / nand_base.c
1 /*
2  *  drivers/mtd/nand.c
3  *
4  *  Overview:
5  *   This is the generic MTD driver for NAND flash devices. It should be
6  *   capable of working with almost all NAND chips currently available.
7  *   Basic support for AG-AND chips is provided.
8  *
9  *      Additional technical information is available on
10  *      http://www.linux-mtd.infradead.org/doc/nand.html
11  *
12  *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
13  *                2002-2006 Thomas Gleixner (tglx@linutronix.de)
14  *
15  *  Credits:
16  *      David Woodhouse for adding multichip support
17  *
18  *      Aleph One Ltd. and Toby Churchill Ltd. for supporting the
19  *      rework for 2K page size chips
20  *
21  *  TODO:
22  *      Enable cached programming for 2k page size chips
23  *      Check, if mtd->ecctype should be set to MTD_ECC_HW
24  *      if we have HW ECC support.
25  *      The AG-AND chips have nice features for speed improvement,
26  *      which are not supported yet. Read / program 4 pages in one go.
27  *      BBT table is not serialized, has to be fixed
28  *
29  * This program is free software; you can redistribute it and/or modify
30  * it under the terms of the GNU General Public License version 2 as
31  * published by the Free Software Foundation.
32  *
33  */
34
35 #include <linux/module.h>
36 #include <linux/delay.h>
37 #include <linux/errno.h>
38 #include <linux/err.h>
39 #include <linux/sched.h>
40 #include <linux/slab.h>
41 #include <linux/types.h>
42 #include <linux/mtd/mtd.h>
43 #include <linux/mtd/nand.h>
44 #include <linux/mtd/nand_ecc.h>
45 #include <linux/mtd/nand_bch.h>
46 #include <linux/interrupt.h>
47 #include <linux/bitops.h>
48 #include <linux/leds.h>
49 #include <linux/io.h>
50 #include <linux/mtd/partitions.h>
51
52 /* Define default oob placement schemes for large and small page devices */
53 static struct nand_ecclayout nand_oob_8 = {
54         .eccbytes = 3,
55         .eccpos = {0, 1, 2},
56         .oobfree = {
57                 {.offset = 3,
58                  .length = 2},
59                 {.offset = 6,
60                  .length = 2} }
61 };
62
63 static struct nand_ecclayout nand_oob_16 = {
64         .eccbytes = 6,
65         .eccpos = {0, 1, 2, 3, 6, 7},
66         .oobfree = {
67                 {.offset = 8,
68                  . length = 8} }
69 };
70
71 static struct nand_ecclayout nand_oob_64 = {
72         .eccbytes = 24,
73         .eccpos = {
74                    40, 41, 42, 43, 44, 45, 46, 47,
75                    48, 49, 50, 51, 52, 53, 54, 55,
76                    56, 57, 58, 59, 60, 61, 62, 63},
77         .oobfree = {
78                 {.offset = 2,
79                  .length = 38} }
80 };
81
82 static struct nand_ecclayout nand_oob_128 = {
83         .eccbytes = 48,
84         .eccpos = {
85                    80, 81, 82, 83, 84, 85, 86, 87,
86                    88, 89, 90, 91, 92, 93, 94, 95,
87                    96, 97, 98, 99, 100, 101, 102, 103,
88                    104, 105, 106, 107, 108, 109, 110, 111,
89                    112, 113, 114, 115, 116, 117, 118, 119,
90                    120, 121, 122, 123, 124, 125, 126, 127},
91         .oobfree = {
92                 {.offset = 2,
93                  .length = 78} }
94 };
95
96 static int nand_get_device(struct mtd_info *mtd, int new_state);
97
98 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
99                              struct mtd_oob_ops *ops);
100
101 /*
102  * For devices which display every fart in the system on a separate LED. Is
103  * compiled away when LED support is disabled.
104  */
105 DEFINE_LED_TRIGGER(nand_led_trigger);
106
107 static int check_offs_len(struct mtd_info *mtd,
108                                         loff_t ofs, uint64_t len)
109 {
110         struct nand_chip *chip = mtd->priv;
111         int ret = 0;
112
113         /* Start address must align on block boundary */
114         if (ofs & ((1 << chip->phys_erase_shift) - 1)) {
115                 pr_debug("%s: unaligned address\n", __func__);
116                 ret = -EINVAL;
117         }
118
119         /* Length must align on block boundary */
120         if (len & ((1 << chip->phys_erase_shift) - 1)) {
121                 pr_debug("%s: length not block aligned\n", __func__);
122                 ret = -EINVAL;
123         }
124
125         return ret;
126 }
127
128 /**
129  * nand_release_device - [GENERIC] release chip
130  * @mtd: MTD device structure
131  *
132  * Release chip lock and wake up anyone waiting on the device.
133  */
134 static void nand_release_device(struct mtd_info *mtd)
135 {
136         struct nand_chip *chip = mtd->priv;
137
138         /* Release the controller and the chip */
139         spin_lock(&chip->controller->lock);
140         chip->controller->active = NULL;
141         chip->state = FL_READY;
142         wake_up(&chip->controller->wq);
143         spin_unlock(&chip->controller->lock);
144 }
145
146 /**
147  * nand_read_byte - [DEFAULT] read one byte from the chip
148  * @mtd: MTD device structure
149  *
150  * Default read function for 8bit buswidth
151  */
152 static uint8_t nand_read_byte(struct mtd_info *mtd)
153 {
154         struct nand_chip *chip = mtd->priv;
155         return readb(chip->IO_ADDR_R);
156 }
157
158 /**
159  * nand_read_byte16 - [DEFAULT] read one byte endianness aware from the chip
160  * nand_read_byte16 - [DEFAULT] read one byte endianness aware from the chip
161  * @mtd: MTD device structure
162  *
163  * Default read function for 16bit buswidth with endianness conversion.
164  *
165  */
166 static uint8_t nand_read_byte16(struct mtd_info *mtd)
167 {
168         struct nand_chip *chip = mtd->priv;
169         return (uint8_t) cpu_to_le16(readw(chip->IO_ADDR_R));
170 }
171
172 /**
173  * nand_read_word - [DEFAULT] read one word from the chip
174  * @mtd: MTD device structure
175  *
176  * Default read function for 16bit buswidth without endianness conversion.
177  */
178 static u16 nand_read_word(struct mtd_info *mtd)
179 {
180         struct nand_chip *chip = mtd->priv;
181         return readw(chip->IO_ADDR_R);
182 }
183
184 /**
185  * nand_select_chip - [DEFAULT] control CE line
186  * @mtd: MTD device structure
187  * @chipnr: chipnumber to select, -1 for deselect
188  *
189  * Default select function for 1 chip devices.
190  */
191 static void nand_select_chip(struct mtd_info *mtd, int chipnr)
192 {
193         struct nand_chip *chip = mtd->priv;
194
195         switch (chipnr) {
196         case -1:
197                 chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
198                 break;
199         case 0:
200                 break;
201
202         default:
203                 BUG();
204         }
205 }
206
207 /**
208  * nand_write_buf - [DEFAULT] write buffer to chip
209  * @mtd: MTD device structure
210  * @buf: data buffer
211  * @len: number of bytes to write
212  *
213  * Default write function for 8bit buswidth.
214  */
215 static void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
216 {
217         int i;
218         struct nand_chip *chip = mtd->priv;
219
220         for (i = 0; i < len; i++)
221                 writeb(buf[i], chip->IO_ADDR_W);
222 }
223
224 /**
225  * nand_read_buf - [DEFAULT] read chip data into buffer
226  * @mtd: MTD device structure
227  * @buf: buffer to store date
228  * @len: number of bytes to read
229  *
230  * Default read function for 8bit buswidth.
231  */
232 static void nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
233 {
234         int i;
235         struct nand_chip *chip = mtd->priv;
236
237         for (i = 0; i < len; i++)
238                 buf[i] = readb(chip->IO_ADDR_R);
239 }
240
241 /**
242  * nand_write_buf16 - [DEFAULT] write buffer to chip
243  * @mtd: MTD device structure
244  * @buf: data buffer
245  * @len: number of bytes to write
246  *
247  * Default write function for 16bit buswidth.
248  */
249 static void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
250 {
251         int i;
252         struct nand_chip *chip = mtd->priv;
253         u16 *p = (u16 *) buf;
254         len >>= 1;
255
256         for (i = 0; i < len; i++)
257                 writew(p[i], chip->IO_ADDR_W);
258
259 }
260
261 /**
262  * nand_read_buf16 - [DEFAULT] read chip data into buffer
263  * @mtd: MTD device structure
264  * @buf: buffer to store date
265  * @len: number of bytes to read
266  *
267  * Default read function for 16bit buswidth.
268  */
269 static void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
270 {
271         int i;
272         struct nand_chip *chip = mtd->priv;
273         u16 *p = (u16 *) buf;
274         len >>= 1;
275
276         for (i = 0; i < len; i++)
277                 p[i] = readw(chip->IO_ADDR_R);
278 }
279
280 /**
281  * nand_block_bad - [DEFAULT] Read bad block marker from the chip
282  * @mtd: MTD device structure
283  * @ofs: offset from device start
284  * @getchip: 0, if the chip is already selected
285  *
286  * Check, if the block is bad.
287  */
288 static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
289 {
290         int page, chipnr, res = 0, i = 0;
291         struct nand_chip *chip = mtd->priv;
292         u16 bad;
293
294         if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
295                 ofs += mtd->erasesize - mtd->writesize;
296
297         page = (int)(ofs >> chip->page_shift) & chip->pagemask;
298
299         if (getchip) {
300                 chipnr = (int)(ofs >> chip->chip_shift);
301
302                 nand_get_device(mtd, FL_READING);
303
304                 /* Select the NAND device */
305                 chip->select_chip(mtd, chipnr);
306         }
307
308         do {
309                 if (chip->options & NAND_BUSWIDTH_16) {
310                         chip->cmdfunc(mtd, NAND_CMD_READOOB,
311                                         chip->badblockpos & 0xFE, page);
312                         bad = cpu_to_le16(chip->read_word(mtd));
313                         if (chip->badblockpos & 0x1)
314                                 bad >>= 8;
315                         else
316                                 bad &= 0xFF;
317                 } else {
318                         chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos,
319                                         page);
320                         bad = chip->read_byte(mtd);
321                 }
322
323                 if (likely(chip->badblockbits == 8))
324                         res = bad != 0xFF;
325                 else
326                         res = hweight8(bad) < chip->badblockbits;
327                 ofs += mtd->writesize;
328                 page = (int)(ofs >> chip->page_shift) & chip->pagemask;
329                 i++;
330         } while (!res && i < 2 && (chip->bbt_options & NAND_BBT_SCAN2NDPAGE));
331
332         if (getchip) {
333                 chip->select_chip(mtd, -1);
334                 nand_release_device(mtd);
335         }
336
337         return res;
338 }
339
340 /**
341  * nand_default_block_markbad - [DEFAULT] mark a block bad
342  * @mtd: MTD device structure
343  * @ofs: offset from device start
344  *
345  * This is the default implementation, which can be overridden by a hardware
346  * specific driver. We try operations in the following order, according to our
347  * bbt_options (NAND_BBT_NO_OOB_BBM and NAND_BBT_USE_FLASH):
348  *  (1) erase the affected block, to allow OOB marker to be written cleanly
349  *  (2) update in-memory BBT
350  *  (3) write bad block marker to OOB area of affected block
351  *  (4) update flash-based BBT
352  * Note that we retain the first error encountered in (3) or (4), finish the
353  * procedures, and dump the error in the end.
354 */
355 static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
356 {
357         struct nand_chip *chip = mtd->priv;
358         uint8_t buf[2] = { 0, 0 };
359         int block, res, ret = 0, i = 0;
360         int write_oob = !(chip->bbt_options & NAND_BBT_NO_OOB_BBM);
361
362         if (write_oob) {
363                 struct erase_info einfo;
364
365                 /* Attempt erase before marking OOB */
366                 memset(&einfo, 0, sizeof(einfo));
367                 einfo.mtd = mtd;
368                 einfo.addr = ofs;
369                 einfo.len = 1 << chip->phys_erase_shift;
370                 nand_erase_nand(mtd, &einfo, 0);
371         }
372
373         /* Get block number */
374         block = (int)(ofs >> chip->bbt_erase_shift);
375         /* Mark block bad in memory-based BBT */
376         if (chip->bbt)
377                 chip->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
378
379         /* Write bad block marker to OOB */
380         if (write_oob) {
381                 struct mtd_oob_ops ops;
382                 loff_t wr_ofs = ofs;
383
384                 nand_get_device(mtd, FL_WRITING);
385
386                 ops.datbuf = NULL;
387                 ops.oobbuf = buf;
388                 ops.ooboffs = chip->badblockpos;
389                 if (chip->options & NAND_BUSWIDTH_16) {
390                         ops.ooboffs &= ~0x01;
391                         ops.len = ops.ooblen = 2;
392                 } else {
393                         ops.len = ops.ooblen = 1;
394                 }
395                 ops.mode = MTD_OPS_PLACE_OOB;
396
397                 /* Write to first/last page(s) if necessary */
398                 if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
399                         wr_ofs += mtd->erasesize - mtd->writesize;
400                 do {
401                         res = nand_do_write_oob(mtd, wr_ofs, &ops);
402                         if (!ret)
403                                 ret = res;
404
405                         i++;
406                         wr_ofs += mtd->writesize;
407                 } while ((chip->bbt_options & NAND_BBT_SCAN2NDPAGE) && i < 2);
408
409                 nand_release_device(mtd);
410         }
411
412         /* Update flash-based bad block table */
413         if (chip->bbt_options & NAND_BBT_USE_FLASH) {
414                 res = nand_update_bbt(mtd, ofs);
415                 if (!ret)
416                         ret = res;
417         }
418
419         if (!ret)
420                 mtd->ecc_stats.badblocks++;
421
422         return ret;
423 }
424
425 /**
426  * nand_check_wp - [GENERIC] check if the chip is write protected
427  * @mtd: MTD device structure
428  *
429  * Check, if the device is write protected. The function expects, that the
430  * device is already selected.
431  */
432 static int nand_check_wp(struct mtd_info *mtd)
433 {
434         struct nand_chip *chip = mtd->priv;
435
436         /* Broken xD cards report WP despite being writable */
437         if (chip->options & NAND_BROKEN_XD)
438                 return 0;
439
440         /* Check the WP bit */
441         chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
442         return (chip->read_byte(mtd) & NAND_STATUS_WP) ? 0 : 1;
443 }
444
445 /**
446  * nand_block_checkbad - [GENERIC] Check if a block is marked bad
447  * @mtd: MTD device structure
448  * @ofs: offset from device start
449  * @getchip: 0, if the chip is already selected
450  * @allowbbt: 1, if its allowed to access the bbt area
451  *
452  * Check, if the block is bad. Either by reading the bad block table or
453  * calling of the scan function.
454  */
455 static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int getchip,
456                                int allowbbt)
457 {
458         struct nand_chip *chip = mtd->priv;
459
460         if (!chip->bbt)
461                 return chip->block_bad(mtd, ofs, getchip);
462
463         /* Return info from the table */
464         return nand_isbad_bbt(mtd, ofs, allowbbt);
465 }
466
467 /**
468  * panic_nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
469  * @mtd: MTD device structure
470  * @timeo: Timeout
471  *
472  * Helper function for nand_wait_ready used when needing to wait in interrupt
473  * context.
474  */
475 static void panic_nand_wait_ready(struct mtd_info *mtd, unsigned long timeo)
476 {
477         struct nand_chip *chip = mtd->priv;
478         int i;
479
480         /* Wait for the device to get ready */
481         for (i = 0; i < timeo; i++) {
482                 if (chip->dev_ready(mtd))
483                         break;
484                 touch_softlockup_watchdog();
485                 mdelay(1);
486         }
487 }
488
489 /* Wait for the ready pin, after a command. The timeout is caught later. */
490 void nand_wait_ready(struct mtd_info *mtd)
491 {
492         struct nand_chip *chip = mtd->priv;
493         unsigned long timeo = jiffies + msecs_to_jiffies(20);
494
495         /* 400ms timeout */
496         if (in_interrupt() || oops_in_progress)
497                 return panic_nand_wait_ready(mtd, 400);
498
499         led_trigger_event(nand_led_trigger, LED_FULL);
500         /* Wait until command is processed or timeout occurs */
501         do {
502                 if (chip->dev_ready(mtd))
503                         break;
504                 touch_softlockup_watchdog();
505         } while (time_before(jiffies, timeo));
506         led_trigger_event(nand_led_trigger, LED_OFF);
507 }
508 EXPORT_SYMBOL_GPL(nand_wait_ready);
509
510 /**
511  * nand_command - [DEFAULT] Send command to NAND device
512  * @mtd: MTD device structure
513  * @command: the command to be sent
514  * @column: the column address for this command, -1 if none
515  * @page_addr: the page address for this command, -1 if none
516  *
517  * Send command to NAND device. This function is used for small page devices
518  * (256/512 Bytes per page).
519  */
520 static void nand_command(struct mtd_info *mtd, unsigned int command,
521                          int column, int page_addr)
522 {
523         register struct nand_chip *chip = mtd->priv;
524         int ctrl = NAND_CTRL_CLE | NAND_CTRL_CHANGE;
525
526         /* Write out the command to the device */
527         if (command == NAND_CMD_SEQIN) {
528                 int readcmd;
529
530                 if (column >= mtd->writesize) {
531                         /* OOB area */
532                         column -= mtd->writesize;
533                         readcmd = NAND_CMD_READOOB;
534                 } else if (column < 256) {
535                         /* First 256 bytes --> READ0 */
536                         readcmd = NAND_CMD_READ0;
537                 } else {
538                         column -= 256;
539                         readcmd = NAND_CMD_READ1;
540                 }
541                 chip->cmd_ctrl(mtd, readcmd, ctrl);
542                 ctrl &= ~NAND_CTRL_CHANGE;
543         }
544         chip->cmd_ctrl(mtd, command, ctrl);
545
546         /* Address cycle, when necessary */
547         ctrl = NAND_CTRL_ALE | NAND_CTRL_CHANGE;
548         /* Serially input address */
549         if (column != -1) {
550                 /* Adjust columns for 16 bit buswidth */
551                 if (chip->options & NAND_BUSWIDTH_16)
552                         column >>= 1;
553                 chip->cmd_ctrl(mtd, column, ctrl);
554                 ctrl &= ~NAND_CTRL_CHANGE;
555         }
556         if (page_addr != -1) {
557                 chip->cmd_ctrl(mtd, page_addr, ctrl);
558                 ctrl &= ~NAND_CTRL_CHANGE;
559                 chip->cmd_ctrl(mtd, page_addr >> 8, ctrl);
560                 /* One more address cycle for devices > 32MiB */
561                 if (chip->chipsize > (32 << 20))
562                         chip->cmd_ctrl(mtd, page_addr >> 16, ctrl);
563         }
564         chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
565
566         /*
567          * Program and erase have their own busy handlers status and sequential
568          * in needs no delay
569          */
570         switch (command) {
571
572         case NAND_CMD_PAGEPROG:
573         case NAND_CMD_ERASE1:
574         case NAND_CMD_ERASE2:
575         case NAND_CMD_SEQIN:
576         case NAND_CMD_STATUS:
577                 return;
578
579         case NAND_CMD_RESET:
580                 if (chip->dev_ready)
581                         break;
582                 udelay(chip->chip_delay);
583                 chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
584                                NAND_CTRL_CLE | NAND_CTRL_CHANGE);
585                 chip->cmd_ctrl(mtd,
586                                NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
587                 while (!(chip->read_byte(mtd) & NAND_STATUS_READY))
588                                 ;
589                 return;
590
591                 /* This applies to read commands */
592         default:
593                 /*
594                  * If we don't have access to the busy pin, we apply the given
595                  * command delay
596                  */
597                 if (!chip->dev_ready) {
598                         udelay(chip->chip_delay);
599                         return;
600                 }
601         }
602         /*
603          * Apply this short delay always to ensure that we do wait tWB in
604          * any case on any machine.
605          */
606         ndelay(100);
607
608         nand_wait_ready(mtd);
609 }
610
611 /**
612  * nand_command_lp - [DEFAULT] Send command to NAND large page device
613  * @mtd: MTD device structure
614  * @command: the command to be sent
615  * @column: the column address for this command, -1 if none
616  * @page_addr: the page address for this command, -1 if none
617  *
618  * Send command to NAND device. This is the version for the new large page
619  * devices. We don't have the separate regions as we have in the small page
620  * devices. We must emulate NAND_CMD_READOOB to keep the code compatible.
621  */
622 static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
623                             int column, int page_addr)
624 {
625         register struct nand_chip *chip = mtd->priv;
626
627         /* Emulate NAND_CMD_READOOB */
628         if (command == NAND_CMD_READOOB) {
629                 column += mtd->writesize;
630                 command = NAND_CMD_READ0;
631         }
632
633         /* Command latch cycle */
634         chip->cmd_ctrl(mtd, command & 0xff,
635                        NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
636
637         if (column != -1 || page_addr != -1) {
638                 int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE;
639
640                 /* Serially input address */
641                 if (column != -1) {
642                         /* Adjust columns for 16 bit buswidth */
643                         if (chip->options & NAND_BUSWIDTH_16)
644                                 column >>= 1;
645                         chip->cmd_ctrl(mtd, column, ctrl);
646                         ctrl &= ~NAND_CTRL_CHANGE;
647                         chip->cmd_ctrl(mtd, column >> 8, ctrl);
648                 }
649                 if (page_addr != -1) {
650                         chip->cmd_ctrl(mtd, page_addr, ctrl);
651                         chip->cmd_ctrl(mtd, page_addr >> 8,
652                                        NAND_NCE | NAND_ALE);
653                         /* One more address cycle for devices > 128MiB */
654                         if (chip->chipsize > (128 << 20))
655                                 chip->cmd_ctrl(mtd, page_addr >> 16,
656                                                NAND_NCE | NAND_ALE);
657                 }
658         }
659         chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
660
661         /*
662          * Program and erase have their own busy handlers status, sequential
663          * in, and deplete1 need no delay.
664          */
665         switch (command) {
666
667         case NAND_CMD_CACHEDPROG:
668         case NAND_CMD_PAGEPROG:
669         case NAND_CMD_ERASE1:
670         case NAND_CMD_ERASE2:
671         case NAND_CMD_SEQIN:
672         case NAND_CMD_RNDIN:
673         case NAND_CMD_STATUS:
674         case NAND_CMD_DEPLETE1:
675                 return;
676
677         case NAND_CMD_STATUS_ERROR:
678         case NAND_CMD_STATUS_ERROR0:
679         case NAND_CMD_STATUS_ERROR1:
680         case NAND_CMD_STATUS_ERROR2:
681         case NAND_CMD_STATUS_ERROR3:
682                 /* Read error status commands require only a short delay */
683                 udelay(chip->chip_delay);
684                 return;
685
686         case NAND_CMD_RESET:
687                 if (chip->dev_ready)
688                         break;
689                 udelay(chip->chip_delay);
690                 chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
691                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
692                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
693                                NAND_NCE | NAND_CTRL_CHANGE);
694                 while (!(chip->read_byte(mtd) & NAND_STATUS_READY))
695                                 ;
696                 return;
697
698         case NAND_CMD_RNDOUT:
699                 /* No ready / busy check necessary */
700                 chip->cmd_ctrl(mtd, NAND_CMD_RNDOUTSTART,
701                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
702                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
703                                NAND_NCE | NAND_CTRL_CHANGE);
704                 return;
705
706         case NAND_CMD_READ0:
707                 chip->cmd_ctrl(mtd, NAND_CMD_READSTART,
708                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
709                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
710                                NAND_NCE | NAND_CTRL_CHANGE);
711
712                 /* This applies to read commands */
713         default:
714                 /*
715                  * If we don't have access to the busy pin, we apply the given
716                  * command delay.
717                  */
718                 if (!chip->dev_ready) {
719                         udelay(chip->chip_delay);
720                         return;
721                 }
722         }
723
724         /*
725          * Apply this short delay always to ensure that we do wait tWB in
726          * any case on any machine.
727          */
728         ndelay(100);
729
730         nand_wait_ready(mtd);
731 }
732
733 /**
734  * panic_nand_get_device - [GENERIC] Get chip for selected access
735  * @chip: the nand chip descriptor
736  * @mtd: MTD device structure
737  * @new_state: the state which is requested
738  *
739  * Used when in panic, no locks are taken.
740  */
741 static void panic_nand_get_device(struct nand_chip *chip,
742                       struct mtd_info *mtd, int new_state)
743 {
744         /* Hardware controller shared among independent devices */
745         chip->controller->active = chip;
746         chip->state = new_state;
747 }
748
749 /**
750  * nand_get_device - [GENERIC] Get chip for selected access
751  * @mtd: MTD device structure
752  * @new_state: the state which is requested
753  *
754  * Get the device and lock it for exclusive access
755  */
756 static int
757 nand_get_device(struct mtd_info *mtd, int new_state)
758 {
759         struct nand_chip *chip = mtd->priv;
760         spinlock_t *lock = &chip->controller->lock;
761         wait_queue_head_t *wq = &chip->controller->wq;
762         DECLARE_WAITQUEUE(wait, current);
763 retry:
764         spin_lock(lock);
765
766         /* Hardware controller shared among independent devices */
767         if (!chip->controller->active)
768                 chip->controller->active = chip;
769
770         if (chip->controller->active == chip && chip->state == FL_READY) {
771                 chip->state = new_state;
772                 spin_unlock(lock);
773                 return 0;
774         }
775         if (new_state == FL_PM_SUSPENDED) {
776                 if (chip->controller->active->state == FL_PM_SUSPENDED) {
777                         chip->state = FL_PM_SUSPENDED;
778                         spin_unlock(lock);
779                         return 0;
780                 }
781         }
782         set_current_state(TASK_UNINTERRUPTIBLE);
783         add_wait_queue(wq, &wait);
784         spin_unlock(lock);
785         schedule();
786         remove_wait_queue(wq, &wait);
787         goto retry;
788 }
789
790 /**
791  * panic_nand_wait - [GENERIC] wait until the command is done
792  * @mtd: MTD device structure
793  * @chip: NAND chip structure
794  * @timeo: timeout
795  *
796  * Wait for command done. This is a helper function for nand_wait used when
797  * we are in interrupt context. May happen when in panic and trying to write
798  * an oops through mtdoops.
799  */
800 static void panic_nand_wait(struct mtd_info *mtd, struct nand_chip *chip,
801                             unsigned long timeo)
802 {
803         int i;
804         for (i = 0; i < timeo; i++) {
805                 if (chip->dev_ready) {
806                         if (chip->dev_ready(mtd))
807                                 break;
808                 } else {
809                         if (chip->read_byte(mtd) & NAND_STATUS_READY)
810                                 break;
811                 }
812                 mdelay(1);
813         }
814 }
815
816 /**
817  * nand_wait - [DEFAULT] wait until the command is done
818  * @mtd: MTD device structure
819  * @chip: NAND chip structure
820  *
821  * Wait for command done. This applies to erase and program only. Erase can
822  * take up to 400ms and program up to 20ms according to general NAND and
823  * SmartMedia specs.
824  */
825 static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
826 {
827
828         int status, state = chip->state;
829         unsigned long timeo = (state == FL_ERASING ? 400 : 20);
830
831         led_trigger_event(nand_led_trigger, LED_FULL);
832
833         /*
834          * Apply this short delay always to ensure that we do wait tWB in any
835          * case on any machine.
836          */
837         ndelay(100);
838
839         if ((state == FL_ERASING) && (chip->options & NAND_IS_AND))
840                 chip->cmdfunc(mtd, NAND_CMD_STATUS_MULTI, -1, -1);
841         else
842                 chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
843
844         if (in_interrupt() || oops_in_progress)
845                 panic_nand_wait(mtd, chip, timeo);
846         else {
847                 timeo = jiffies + msecs_to_jiffies(timeo);
848                 while (time_before(jiffies, timeo)) {
849                         if (chip->dev_ready) {
850                                 if (chip->dev_ready(mtd))
851                                         break;
852                         } else {
853                                 if (chip->read_byte(mtd) & NAND_STATUS_READY)
854                                         break;
855                         }
856                         cond_resched();
857                 }
858         }
859         led_trigger_event(nand_led_trigger, LED_OFF);
860
861         status = (int)chip->read_byte(mtd);
862         /* This can happen if in case of timeout or buggy dev_ready */
863         WARN_ON(!(status & NAND_STATUS_READY));
864         return status;
865 }
866
867 /**
868  * __nand_unlock - [REPLACEABLE] unlocks specified locked blocks
869  * @mtd: mtd info
870  * @ofs: offset to start unlock from
871  * @len: length to unlock
872  * @invert: when = 0, unlock the range of blocks within the lower and
873  *                    upper boundary address
874  *          when = 1, unlock the range of blocks outside the boundaries
875  *                    of the lower and upper boundary address
876  *
877  * Returs unlock status.
878  */
879 static int __nand_unlock(struct mtd_info *mtd, loff_t ofs,
880                                         uint64_t len, int invert)
881 {
882         int ret = 0;
883         int status, page;
884         struct nand_chip *chip = mtd->priv;
885
886         /* Submit address of first page to unlock */
887         page = ofs >> chip->page_shift;
888         chip->cmdfunc(mtd, NAND_CMD_UNLOCK1, -1, page & chip->pagemask);
889
890         /* Submit address of last page to unlock */
891         page = (ofs + len) >> chip->page_shift;
892         chip->cmdfunc(mtd, NAND_CMD_UNLOCK2, -1,
893                                 (page | invert) & chip->pagemask);
894
895         /* Call wait ready function */
896         status = chip->waitfunc(mtd, chip);
897         /* See if device thinks it succeeded */
898         if (status & NAND_STATUS_FAIL) {
899                 pr_debug("%s: error status = 0x%08x\n",
900                                         __func__, status);
901                 ret = -EIO;
902         }
903
904         return ret;
905 }
906
907 /**
908  * nand_unlock - [REPLACEABLE] unlocks specified locked blocks
909  * @mtd: mtd info
910  * @ofs: offset to start unlock from
911  * @len: length to unlock
912  *
913  * Returns unlock status.
914  */
915 int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
916 {
917         int ret = 0;
918         int chipnr;
919         struct nand_chip *chip = mtd->priv;
920
921         pr_debug("%s: start = 0x%012llx, len = %llu\n",
922                         __func__, (unsigned long long)ofs, len);
923
924         if (check_offs_len(mtd, ofs, len))
925                 ret = -EINVAL;
926
927         /* Align to last block address if size addresses end of the device */
928         if (ofs + len == mtd->size)
929                 len -= mtd->erasesize;
930
931         nand_get_device(mtd, FL_UNLOCKING);
932
933         /* Shift to get chip number */
934         chipnr = ofs >> chip->chip_shift;
935
936         chip->select_chip(mtd, chipnr);
937
938         /* Check, if it is write protected */
939         if (nand_check_wp(mtd)) {
940                 pr_debug("%s: device is write protected!\n",
941                                         __func__);
942                 ret = -EIO;
943                 goto out;
944         }
945
946         ret = __nand_unlock(mtd, ofs, len, 0);
947
948 out:
949         chip->select_chip(mtd, -1);
950         nand_release_device(mtd);
951
952         return ret;
953 }
954 EXPORT_SYMBOL(nand_unlock);
955
956 /**
957  * nand_lock - [REPLACEABLE] locks all blocks present in the device
958  * @mtd: mtd info
959  * @ofs: offset to start unlock from
960  * @len: length to unlock
961  *
962  * This feature is not supported in many NAND parts. 'Micron' NAND parts do
963  * have this feature, but it allows only to lock all blocks, not for specified
964  * range for block. Implementing 'lock' feature by making use of 'unlock', for
965  * now.
966  *
967  * Returns lock status.
968  */
969 int nand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
970 {
971         int ret = 0;
972         int chipnr, status, page;
973         struct nand_chip *chip = mtd->priv;
974
975         pr_debug("%s: start = 0x%012llx, len = %llu\n",
976                         __func__, (unsigned long long)ofs, len);
977
978         if (check_offs_len(mtd, ofs, len))
979                 ret = -EINVAL;
980
981         nand_get_device(mtd, FL_LOCKING);
982
983         /* Shift to get chip number */
984         chipnr = ofs >> chip->chip_shift;
985
986         chip->select_chip(mtd, chipnr);
987
988         /* Check, if it is write protected */
989         if (nand_check_wp(mtd)) {
990                 pr_debug("%s: device is write protected!\n",
991                                         __func__);
992                 status = MTD_ERASE_FAILED;
993                 ret = -EIO;
994                 goto out;
995         }
996
997         /* Submit address of first page to lock */
998         page = ofs >> chip->page_shift;
999         chip->cmdfunc(mtd, NAND_CMD_LOCK, -1, page & chip->pagemask);
1000
1001         /* Call wait ready function */
1002         status = chip->waitfunc(mtd, chip);
1003         /* See if device thinks it succeeded */
1004         if (status & NAND_STATUS_FAIL) {
1005                 pr_debug("%s: error status = 0x%08x\n",
1006                                         __func__, status);
1007                 ret = -EIO;
1008                 goto out;
1009         }
1010
1011         ret = __nand_unlock(mtd, ofs, len, 0x1);
1012
1013 out:
1014         chip->select_chip(mtd, -1);
1015         nand_release_device(mtd);
1016
1017         return ret;
1018 }
1019 EXPORT_SYMBOL(nand_lock);
1020
1021 /**
1022  * nand_read_page_raw - [INTERN] read raw page data without ecc
1023  * @mtd: mtd info structure
1024  * @chip: nand chip info structure
1025  * @buf: buffer to store read data
1026  * @oob_required: caller requires OOB data read to chip->oob_poi
1027  * @page: page number to read
1028  *
1029  * Not for syndrome calculating ECC controllers, which use a special oob layout.
1030  */
1031 static int nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1032                               uint8_t *buf, int oob_required, int page)
1033 {
1034         chip->read_buf(mtd, buf, mtd->writesize);
1035         if (oob_required)
1036                 chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1037         return 0;
1038 }
1039
1040 /**
1041  * nand_read_page_raw_syndrome - [INTERN] read raw page data without ecc
1042  * @mtd: mtd info structure
1043  * @chip: nand chip info structure
1044  * @buf: buffer to store read data
1045  * @oob_required: caller requires OOB data read to chip->oob_poi
1046  * @page: page number to read
1047  *
1048  * We need a special oob layout and handling even when OOB isn't used.
1049  */
1050 static int nand_read_page_raw_syndrome(struct mtd_info *mtd,
1051                                        struct nand_chip *chip, uint8_t *buf,
1052                                        int oob_required, int page)
1053 {
1054         int eccsize = chip->ecc.size;
1055         int eccbytes = chip->ecc.bytes;
1056         uint8_t *oob = chip->oob_poi;
1057         int steps, size;
1058
1059         for (steps = chip->ecc.steps; steps > 0; steps--) {
1060                 chip->read_buf(mtd, buf, eccsize);
1061                 buf += eccsize;
1062
1063                 if (chip->ecc.prepad) {
1064                         chip->read_buf(mtd, oob, chip->ecc.prepad);
1065                         oob += chip->ecc.prepad;
1066                 }
1067
1068                 chip->read_buf(mtd, oob, eccbytes);
1069                 oob += eccbytes;
1070
1071                 if (chip->ecc.postpad) {
1072                         chip->read_buf(mtd, oob, chip->ecc.postpad);
1073                         oob += chip->ecc.postpad;
1074                 }
1075         }
1076
1077         size = mtd->oobsize - (oob - chip->oob_poi);
1078         if (size)
1079                 chip->read_buf(mtd, oob, size);
1080
1081         return 0;
1082 }
1083
1084 /**
1085  * nand_read_page_swecc - [REPLACEABLE] software ECC based page read function
1086  * @mtd: mtd info structure
1087  * @chip: nand chip info structure
1088  * @buf: buffer to store read data
1089  * @oob_required: caller requires OOB data read to chip->oob_poi
1090  * @page: page number to read
1091  */
1092 static int nand_read_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
1093                                 uint8_t *buf, int oob_required, int page)
1094 {
1095         int i, eccsize = chip->ecc.size;
1096         int eccbytes = chip->ecc.bytes;
1097         int eccsteps = chip->ecc.steps;
1098         uint8_t *p = buf;
1099         uint8_t *ecc_calc = chip->buffers->ecccalc;
1100         uint8_t *ecc_code = chip->buffers->ecccode;
1101         uint32_t *eccpos = chip->ecc.layout->eccpos;
1102         unsigned int max_bitflips = 0;
1103
1104         chip->ecc.read_page_raw(mtd, chip, buf, 1, page);
1105
1106         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
1107                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1108
1109         for (i = 0; i < chip->ecc.total; i++)
1110                 ecc_code[i] = chip->oob_poi[eccpos[i]];
1111
1112         eccsteps = chip->ecc.steps;
1113         p = buf;
1114
1115         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1116                 int stat;
1117
1118                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
1119                 if (stat < 0) {
1120                         mtd->ecc_stats.failed++;
1121                 } else {
1122                         mtd->ecc_stats.corrected += stat;
1123                         max_bitflips = max_t(unsigned int, max_bitflips, stat);
1124                 }
1125         }
1126         return max_bitflips;
1127 }
1128
1129 /**
1130  * nand_read_subpage - [REPLACEABLE] software ECC based sub-page read function
1131  * @mtd: mtd info structure
1132  * @chip: nand chip info structure
1133  * @data_offs: offset of requested data within the page
1134  * @readlen: data length
1135  * @bufpoi: buffer to store read data
1136  */
1137 static int nand_read_subpage(struct mtd_info *mtd, struct nand_chip *chip,
1138                         uint32_t data_offs, uint32_t readlen, uint8_t *bufpoi)
1139 {
1140         int start_step, end_step, num_steps;
1141         uint32_t *eccpos = chip->ecc.layout->eccpos;
1142         uint8_t *p;
1143         int data_col_addr, i, gaps = 0;
1144         int datafrag_len, eccfrag_len, aligned_len, aligned_pos;
1145         int busw = (chip->options & NAND_BUSWIDTH_16) ? 2 : 1;
1146         int index = 0;
1147         unsigned int max_bitflips = 0;
1148
1149         /* Column address within the page aligned to ECC size (256bytes) */
1150         start_step = data_offs / chip->ecc.size;
1151         end_step = (data_offs + readlen - 1) / chip->ecc.size;
1152         num_steps = end_step - start_step + 1;
1153
1154         /* Data size aligned to ECC ecc.size */
1155         datafrag_len = num_steps * chip->ecc.size;
1156         eccfrag_len = num_steps * chip->ecc.bytes;
1157
1158         data_col_addr = start_step * chip->ecc.size;
1159         /* If we read not a page aligned data */
1160         if (data_col_addr != 0)
1161                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_col_addr, -1);
1162
1163         p = bufpoi + data_col_addr;
1164         chip->read_buf(mtd, p, datafrag_len);
1165
1166         /* Calculate ECC */
1167         for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size)
1168                 chip->ecc.calculate(mtd, p, &chip->buffers->ecccalc[i]);
1169
1170         /*
1171          * The performance is faster if we position offsets according to
1172          * ecc.pos. Let's make sure that there are no gaps in ECC positions.
1173          */
1174         for (i = 0; i < eccfrag_len - 1; i++) {
1175                 if (eccpos[i + start_step * chip->ecc.bytes] + 1 !=
1176                         eccpos[i + start_step * chip->ecc.bytes + 1]) {
1177                         gaps = 1;
1178                         break;
1179                 }
1180         }
1181         if (gaps) {
1182                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
1183                 chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1184         } else {
1185                 /*
1186                  * Send the command to read the particular ECC bytes take care
1187                  * about buswidth alignment in read_buf.
1188                  */
1189                 index = start_step * chip->ecc.bytes;
1190
1191                 aligned_pos = eccpos[index] & ~(busw - 1);
1192                 aligned_len = eccfrag_len;
1193                 if (eccpos[index] & (busw - 1))
1194                         aligned_len++;
1195                 if (eccpos[index + (num_steps * chip->ecc.bytes)] & (busw - 1))
1196                         aligned_len++;
1197
1198                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
1199                                         mtd->writesize + aligned_pos, -1);
1200                 chip->read_buf(mtd, &chip->oob_poi[aligned_pos], aligned_len);
1201         }
1202
1203         for (i = 0; i < eccfrag_len; i++)
1204                 chip->buffers->ecccode[i] = chip->oob_poi[eccpos[i + index]];
1205
1206         p = bufpoi + data_col_addr;
1207         for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size) {
1208                 int stat;
1209
1210                 stat = chip->ecc.correct(mtd, p,
1211                         &chip->buffers->ecccode[i], &chip->buffers->ecccalc[i]);
1212                 if (stat < 0) {
1213                         mtd->ecc_stats.failed++;
1214                 } else {
1215                         mtd->ecc_stats.corrected += stat;
1216                         max_bitflips = max_t(unsigned int, max_bitflips, stat);
1217                 }
1218         }
1219         return max_bitflips;
1220 }
1221
1222 /**
1223  * nand_read_page_hwecc - [REPLACEABLE] hardware ECC based page read function
1224  * @mtd: mtd info structure
1225  * @chip: nand chip info structure
1226  * @buf: buffer to store read data
1227  * @oob_required: caller requires OOB data read to chip->oob_poi
1228  * @page: page number to read
1229  *
1230  * Not for syndrome calculating ECC controllers which need a special oob layout.
1231  */
1232 static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
1233                                 uint8_t *buf, int oob_required, int page)
1234 {
1235         int i, eccsize = chip->ecc.size;
1236         int eccbytes = chip->ecc.bytes;
1237         int eccsteps = chip->ecc.steps;
1238         uint8_t *p = buf;
1239         uint8_t *ecc_calc = chip->buffers->ecccalc;
1240         uint8_t *ecc_code = chip->buffers->ecccode;
1241         uint32_t *eccpos = chip->ecc.layout->eccpos;
1242         unsigned int max_bitflips = 0;
1243
1244         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1245                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
1246                 chip->read_buf(mtd, p, eccsize);
1247                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1248         }
1249         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1250
1251         for (i = 0; i < chip->ecc.total; i++)
1252                 ecc_code[i] = chip->oob_poi[eccpos[i]];
1253
1254         eccsteps = chip->ecc.steps;
1255         p = buf;
1256
1257         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1258                 int stat;
1259
1260                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
1261                 if (stat < 0) {
1262                         mtd->ecc_stats.failed++;
1263                 } else {
1264                         mtd->ecc_stats.corrected += stat;
1265                         max_bitflips = max_t(unsigned int, max_bitflips, stat);
1266                 }
1267         }
1268         return max_bitflips;
1269 }
1270
1271 /**
1272  * nand_read_page_hwecc_oob_first - [REPLACEABLE] hw ecc, read oob first
1273  * @mtd: mtd info structure
1274  * @chip: nand chip info structure
1275  * @buf: buffer to store read data
1276  * @oob_required: caller requires OOB data read to chip->oob_poi
1277  * @page: page number to read
1278  *
1279  * Hardware ECC for large page chips, require OOB to be read first. For this
1280  * ECC mode, the write_page method is re-used from ECC_HW. These methods
1281  * read/write ECC from the OOB area, unlike the ECC_HW_SYNDROME support with
1282  * multiple ECC steps, follows the "infix ECC" scheme and reads/writes ECC from
1283  * the data area, by overwriting the NAND manufacturer bad block markings.
1284  */
1285 static int nand_read_page_hwecc_oob_first(struct mtd_info *mtd,
1286         struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
1287 {
1288         int i, eccsize = chip->ecc.size;
1289         int eccbytes = chip->ecc.bytes;
1290         int eccsteps = chip->ecc.steps;
1291         uint8_t *p = buf;
1292         uint8_t *ecc_code = chip->buffers->ecccode;
1293         uint32_t *eccpos = chip->ecc.layout->eccpos;
1294         uint8_t *ecc_calc = chip->buffers->ecccalc;
1295         unsigned int max_bitflips = 0;
1296
1297         /* Read the OOB area first */
1298         chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
1299         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1300         chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
1301
1302         for (i = 0; i < chip->ecc.total; i++)
1303                 ecc_code[i] = chip->oob_poi[eccpos[i]];
1304
1305         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1306                 int stat;
1307
1308                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
1309                 chip->read_buf(mtd, p, eccsize);
1310                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1311
1312                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], NULL);
1313                 if (stat < 0) {
1314                         mtd->ecc_stats.failed++;
1315                 } else {
1316                         mtd->ecc_stats.corrected += stat;
1317                         max_bitflips = max_t(unsigned int, max_bitflips, stat);
1318                 }
1319         }
1320         return max_bitflips;
1321 }
1322
1323 /**
1324  * nand_read_page_syndrome - [REPLACEABLE] hardware ECC syndrome based page read
1325  * @mtd: mtd info structure
1326  * @chip: nand chip info structure
1327  * @buf: buffer to store read data
1328  * @oob_required: caller requires OOB data read to chip->oob_poi
1329  * @page: page number to read
1330  *
1331  * The hw generator calculates the error syndrome automatically. Therefore we
1332  * need a special oob layout and handling.
1333  */
1334 static int nand_read_page_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
1335                                    uint8_t *buf, int oob_required, int page)
1336 {
1337         int i, eccsize = chip->ecc.size;
1338         int eccbytes = chip->ecc.bytes;
1339         int eccsteps = chip->ecc.steps;
1340         uint8_t *p = buf;
1341         uint8_t *oob = chip->oob_poi;
1342         unsigned int max_bitflips = 0;
1343
1344         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1345                 int stat;
1346
1347                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
1348                 chip->read_buf(mtd, p, eccsize);
1349
1350                 if (chip->ecc.prepad) {
1351                         chip->read_buf(mtd, oob, chip->ecc.prepad);
1352                         oob += chip->ecc.prepad;
1353                 }
1354
1355                 chip->ecc.hwctl(mtd, NAND_ECC_READSYN);
1356                 chip->read_buf(mtd, oob, eccbytes);
1357                 stat = chip->ecc.correct(mtd, p, oob, NULL);
1358
1359                 if (stat < 0) {
1360                         mtd->ecc_stats.failed++;
1361                 } else {
1362                         mtd->ecc_stats.corrected += stat;
1363                         max_bitflips = max_t(unsigned int, max_bitflips, stat);
1364                 }
1365
1366                 oob += eccbytes;
1367
1368                 if (chip->ecc.postpad) {
1369                         chip->read_buf(mtd, oob, chip->ecc.postpad);
1370                         oob += chip->ecc.postpad;
1371                 }
1372         }
1373
1374         /* Calculate remaining oob bytes */
1375         i = mtd->oobsize - (oob - chip->oob_poi);
1376         if (i)
1377                 chip->read_buf(mtd, oob, i);
1378
1379         return max_bitflips;
1380 }
1381
1382 /**
1383  * nand_transfer_oob - [INTERN] Transfer oob to client buffer
1384  * @chip: nand chip structure
1385  * @oob: oob destination address
1386  * @ops: oob ops structure
1387  * @len: size of oob to transfer
1388  */
1389 static uint8_t *nand_transfer_oob(struct nand_chip *chip, uint8_t *oob,
1390                                   struct mtd_oob_ops *ops, size_t len)
1391 {
1392         switch (ops->mode) {
1393
1394         case MTD_OPS_PLACE_OOB:
1395         case MTD_OPS_RAW:
1396                 memcpy(oob, chip->oob_poi + ops->ooboffs, len);
1397                 return oob + len;
1398
1399         case MTD_OPS_AUTO_OOB: {
1400                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
1401                 uint32_t boffs = 0, roffs = ops->ooboffs;
1402                 size_t bytes = 0;
1403
1404                 for (; free->length && len; free++, len -= bytes) {
1405                         /* Read request not from offset 0? */
1406                         if (unlikely(roffs)) {
1407                                 if (roffs >= free->length) {
1408                                         roffs -= free->length;
1409                                         continue;
1410                                 }
1411                                 boffs = free->offset + roffs;
1412                                 bytes = min_t(size_t, len,
1413                                               (free->length - roffs));
1414                                 roffs = 0;
1415                         } else {
1416                                 bytes = min_t(size_t, len, free->length);
1417                                 boffs = free->offset;
1418                         }
1419                         memcpy(oob, chip->oob_poi + boffs, bytes);
1420                         oob += bytes;
1421                 }
1422                 return oob;
1423         }
1424         default:
1425                 BUG();
1426         }
1427         return NULL;
1428 }
1429
1430 /**
1431  * nand_do_read_ops - [INTERN] Read data with ECC
1432  * @mtd: MTD device structure
1433  * @from: offset to read from
1434  * @ops: oob ops structure
1435  *
1436  * Internal function. Called with chip held.
1437  */
1438 static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
1439                             struct mtd_oob_ops *ops)
1440 {
1441         int chipnr, page, realpage, col, bytes, aligned, oob_required;
1442         struct nand_chip *chip = mtd->priv;
1443         struct mtd_ecc_stats stats;
1444         int ret = 0;
1445         uint32_t readlen = ops->len;
1446         uint32_t oobreadlen = ops->ooblen;
1447         uint32_t max_oobsize = ops->mode == MTD_OPS_AUTO_OOB ?
1448                 mtd->oobavail : mtd->oobsize;
1449
1450         uint8_t *bufpoi, *oob, *buf;
1451         unsigned int max_bitflips = 0;
1452
1453         stats = mtd->ecc_stats;
1454
1455         chipnr = (int)(from >> chip->chip_shift);
1456         chip->select_chip(mtd, chipnr);
1457
1458         realpage = (int)(from >> chip->page_shift);
1459         page = realpage & chip->pagemask;
1460
1461         col = (int)(from & (mtd->writesize - 1));
1462
1463         buf = ops->datbuf;
1464         oob = ops->oobbuf;
1465         oob_required = oob ? 1 : 0;
1466
1467         while (1) {
1468                 bytes = min(mtd->writesize - col, readlen);
1469                 aligned = (bytes == mtd->writesize);
1470
1471                 /* Is the current page in the buffer? */
1472                 if (realpage != chip->pagebuf || oob) {
1473                         bufpoi = aligned ? buf : chip->buffers->databuf;
1474
1475                         chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
1476
1477                         /*
1478                          * Now read the page into the buffer.  Absent an error,
1479                          * the read methods return max bitflips per ecc step.
1480                          */
1481                         if (unlikely(ops->mode == MTD_OPS_RAW))
1482                                 ret = chip->ecc.read_page_raw(mtd, chip, bufpoi,
1483                                                               oob_required,
1484                                                               page);
1485                         else if (!aligned && NAND_HAS_SUBPAGE_READ(chip) &&
1486                                  !oob)
1487                                 ret = chip->ecc.read_subpage(mtd, chip,
1488                                                         col, bytes, bufpoi);
1489                         else
1490                                 ret = chip->ecc.read_page(mtd, chip, bufpoi,
1491                                                           oob_required, page);
1492                         if (ret < 0) {
1493                                 if (!aligned)
1494                                         /* Invalidate page cache */
1495                                         chip->pagebuf = -1;
1496                                 break;
1497                         }
1498
1499                         max_bitflips = max_t(unsigned int, max_bitflips, ret);
1500
1501                         /* Transfer not aligned data */
1502                         if (!aligned) {
1503                                 if (!NAND_HAS_SUBPAGE_READ(chip) && !oob &&
1504                                     !(mtd->ecc_stats.failed - stats.failed) &&
1505                                     (ops->mode != MTD_OPS_RAW)) {
1506                                         chip->pagebuf = realpage;
1507                                         chip->pagebuf_bitflips = ret;
1508                                 } else {
1509                                         /* Invalidate page cache */
1510                                         chip->pagebuf = -1;
1511                                 }
1512                                 memcpy(buf, chip->buffers->databuf + col, bytes);
1513                         }
1514
1515                         buf += bytes;
1516
1517                         if (unlikely(oob)) {
1518                                 int toread = min(oobreadlen, max_oobsize);
1519
1520                                 if (toread) {
1521                                         oob = nand_transfer_oob(chip,
1522                                                 oob, ops, toread);
1523                                         oobreadlen -= toread;
1524                                 }
1525                         }
1526                 } else {
1527                         memcpy(buf, chip->buffers->databuf + col, bytes);
1528                         buf += bytes;
1529                         max_bitflips = max_t(unsigned int, max_bitflips,
1530                                              chip->pagebuf_bitflips);
1531                 }
1532
1533                 readlen -= bytes;
1534
1535                 if (!readlen)
1536                         break;
1537
1538                 /* For subsequent reads align to page boundary */
1539                 col = 0;
1540                 /* Increment page address */
1541                 realpage++;
1542
1543                 page = realpage & chip->pagemask;
1544                 /* Check, if we cross a chip boundary */
1545                 if (!page) {
1546                         chipnr++;
1547                         chip->select_chip(mtd, -1);
1548                         chip->select_chip(mtd, chipnr);
1549                 }
1550         }
1551         chip->select_chip(mtd, -1);
1552
1553         ops->retlen = ops->len - (size_t) readlen;
1554         if (oob)
1555                 ops->oobretlen = ops->ooblen - oobreadlen;
1556
1557         if (ret < 0)
1558                 return ret;
1559
1560         if (mtd->ecc_stats.failed - stats.failed)
1561                 return -EBADMSG;
1562
1563         return max_bitflips;
1564 }
1565
1566 /**
1567  * nand_read - [MTD Interface] MTD compatibility function for nand_do_read_ecc
1568  * @mtd: MTD device structure
1569  * @from: offset to read from
1570  * @len: number of bytes to read
1571  * @retlen: pointer to variable to store the number of read bytes
1572  * @buf: the databuffer to put data
1573  *
1574  * Get hold of the chip and call nand_do_read.
1575  */
1576 static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
1577                      size_t *retlen, uint8_t *buf)
1578 {
1579         struct mtd_oob_ops ops;
1580         int ret;
1581
1582         nand_get_device(mtd, FL_READING);
1583         ops.len = len;
1584         ops.datbuf = buf;
1585         ops.oobbuf = NULL;
1586         ops.mode = MTD_OPS_PLACE_OOB;
1587         ret = nand_do_read_ops(mtd, from, &ops);
1588         *retlen = ops.retlen;
1589         nand_release_device(mtd);
1590         return ret;
1591 }
1592
1593 /**
1594  * nand_read_oob_std - [REPLACEABLE] the most common OOB data read function
1595  * @mtd: mtd info structure
1596  * @chip: nand chip info structure
1597  * @page: page number to read
1598  */
1599 static int nand_read_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1600                              int page)
1601 {
1602         chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
1603         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1604         return 0;
1605 }
1606
1607 /**
1608  * nand_read_oob_syndrome - [REPLACEABLE] OOB data read function for HW ECC
1609  *                          with syndromes
1610  * @mtd: mtd info structure
1611  * @chip: nand chip info structure
1612  * @page: page number to read
1613  */
1614 static int nand_read_oob_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
1615                                   int page)
1616 {
1617         uint8_t *buf = chip->oob_poi;
1618         int length = mtd->oobsize;
1619         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1620         int eccsize = chip->ecc.size;
1621         uint8_t *bufpoi = buf;
1622         int i, toread, sndrnd = 0, pos;
1623
1624         chip->cmdfunc(mtd, NAND_CMD_READ0, chip->ecc.size, page);
1625         for (i = 0; i < chip->ecc.steps; i++) {
1626                 if (sndrnd) {
1627                         pos = eccsize + i * (eccsize + chunk);
1628                         if (mtd->writesize > 512)
1629                                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, pos, -1);
1630                         else
1631                                 chip->cmdfunc(mtd, NAND_CMD_READ0, pos, page);
1632                 } else
1633                         sndrnd = 1;
1634                 toread = min_t(int, length, chunk);
1635                 chip->read_buf(mtd, bufpoi, toread);
1636                 bufpoi += toread;
1637                 length -= toread;
1638         }
1639         if (length > 0)
1640                 chip->read_buf(mtd, bufpoi, length);
1641
1642         return 0;
1643 }
1644
1645 /**
1646  * nand_write_oob_std - [REPLACEABLE] the most common OOB data write function
1647  * @mtd: mtd info structure
1648  * @chip: nand chip info structure
1649  * @page: page number to write
1650  */
1651 static int nand_write_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1652                               int page)
1653 {
1654         int status = 0;
1655         const uint8_t *buf = chip->oob_poi;
1656         int length = mtd->oobsize;
1657
1658         chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
1659         chip->write_buf(mtd, buf, length);
1660         /* Send command to program the OOB data */
1661         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1662
1663         status = chip->waitfunc(mtd, chip);
1664
1665         return status & NAND_STATUS_FAIL ? -EIO : 0;
1666 }
1667
1668 /**
1669  * nand_write_oob_syndrome - [REPLACEABLE] OOB data write function for HW ECC
1670  *                           with syndrome - only for large page flash
1671  * @mtd: mtd info structure
1672  * @chip: nand chip info structure
1673  * @page: page number to write
1674  */
1675 static int nand_write_oob_syndrome(struct mtd_info *mtd,
1676                                    struct nand_chip *chip, int page)
1677 {
1678         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1679         int eccsize = chip->ecc.size, length = mtd->oobsize;
1680         int i, len, pos, status = 0, sndcmd = 0, steps = chip->ecc.steps;
1681         const uint8_t *bufpoi = chip->oob_poi;
1682
1683         /*
1684          * data-ecc-data-ecc ... ecc-oob
1685          * or
1686          * data-pad-ecc-pad-data-pad .... ecc-pad-oob
1687          */
1688         if (!chip->ecc.prepad && !chip->ecc.postpad) {
1689                 pos = steps * (eccsize + chunk);
1690                 steps = 0;
1691         } else
1692                 pos = eccsize;
1693
1694         chip->cmdfunc(mtd, NAND_CMD_SEQIN, pos, page);
1695         for (i = 0; i < steps; i++) {
1696                 if (sndcmd) {
1697                         if (mtd->writesize <= 512) {
1698                                 uint32_t fill = 0xFFFFFFFF;
1699
1700                                 len = eccsize;
1701                                 while (len > 0) {
1702                                         int num = min_t(int, len, 4);
1703                                         chip->write_buf(mtd, (uint8_t *)&fill,
1704                                                         num);
1705                                         len -= num;
1706                                 }
1707                         } else {
1708                                 pos = eccsize + i * (eccsize + chunk);
1709                                 chip->cmdfunc(mtd, NAND_CMD_RNDIN, pos, -1);
1710                         }
1711                 } else
1712                         sndcmd = 1;
1713                 len = min_t(int, length, chunk);
1714                 chip->write_buf(mtd, bufpoi, len);
1715                 bufpoi += len;
1716                 length -= len;
1717         }
1718         if (length > 0)
1719                 chip->write_buf(mtd, bufpoi, length);
1720
1721         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1722         status = chip->waitfunc(mtd, chip);
1723
1724         return status & NAND_STATUS_FAIL ? -EIO : 0;
1725 }
1726
1727 /**
1728  * nand_do_read_oob - [INTERN] NAND read out-of-band
1729  * @mtd: MTD device structure
1730  * @from: offset to read from
1731  * @ops: oob operations description structure
1732  *
1733  * NAND read out-of-band data from the spare area.
1734  */
1735 static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
1736                             struct mtd_oob_ops *ops)
1737 {
1738         int page, realpage, chipnr;
1739         struct nand_chip *chip = mtd->priv;
1740         struct mtd_ecc_stats stats;
1741         int readlen = ops->ooblen;
1742         int len;
1743         uint8_t *buf = ops->oobbuf;
1744         int ret = 0;
1745
1746         pr_debug("%s: from = 0x%08Lx, len = %i\n",
1747                         __func__, (unsigned long long)from, readlen);
1748
1749         stats = mtd->ecc_stats;
1750
1751         if (ops->mode == MTD_OPS_AUTO_OOB)
1752                 len = chip->ecc.layout->oobavail;
1753         else
1754                 len = mtd->oobsize;
1755
1756         if (unlikely(ops->ooboffs >= len)) {
1757                 pr_debug("%s: attempt to start read outside oob\n",
1758                                 __func__);
1759                 return -EINVAL;
1760         }
1761
1762         /* Do not allow reads past end of device */
1763         if (unlikely(from >= mtd->size ||
1764                      ops->ooboffs + readlen > ((mtd->size >> chip->page_shift) -
1765                                         (from >> chip->page_shift)) * len)) {
1766                 pr_debug("%s: attempt to read beyond end of device\n",
1767                                 __func__);
1768                 return -EINVAL;
1769         }
1770
1771         chipnr = (int)(from >> chip->chip_shift);
1772         chip->select_chip(mtd, chipnr);
1773
1774         /* Shift to get page */
1775         realpage = (int)(from >> chip->page_shift);
1776         page = realpage & chip->pagemask;
1777
1778         while (1) {
1779                 if (ops->mode == MTD_OPS_RAW)
1780                         ret = chip->ecc.read_oob_raw(mtd, chip, page);
1781                 else
1782                         ret = chip->ecc.read_oob(mtd, chip, page);
1783
1784                 if (ret < 0)
1785                         break;
1786
1787                 len = min(len, readlen);
1788                 buf = nand_transfer_oob(chip, buf, ops, len);
1789
1790                 readlen -= len;
1791                 if (!readlen)
1792                         break;
1793
1794                 /* Increment page address */
1795                 realpage++;
1796
1797                 page = realpage & chip->pagemask;
1798                 /* Check, if we cross a chip boundary */
1799                 if (!page) {
1800                         chipnr++;
1801                         chip->select_chip(mtd, -1);
1802                         chip->select_chip(mtd, chipnr);
1803                 }
1804         }
1805         chip->select_chip(mtd, -1);
1806
1807         ops->oobretlen = ops->ooblen - readlen;
1808
1809         if (ret < 0)
1810                 return ret;
1811
1812         if (mtd->ecc_stats.failed - stats.failed)
1813                 return -EBADMSG;
1814
1815         return  mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
1816 }
1817
1818 /**
1819  * nand_read_oob - [MTD Interface] NAND read data and/or out-of-band
1820  * @mtd: MTD device structure
1821  * @from: offset to read from
1822  * @ops: oob operation description structure
1823  *
1824  * NAND read data and/or out-of-band data.
1825  */
1826 static int nand_read_oob(struct mtd_info *mtd, loff_t from,
1827                          struct mtd_oob_ops *ops)
1828 {
1829         int ret = -ENOTSUPP;
1830
1831         ops->retlen = 0;
1832
1833         /* Do not allow reads past end of device */
1834         if (ops->datbuf && (from + ops->len) > mtd->size) {
1835                 pr_debug("%s: attempt to read beyond end of device\n",
1836                                 __func__);
1837                 return -EINVAL;
1838         }
1839
1840         nand_get_device(mtd, FL_READING);
1841
1842         switch (ops->mode) {
1843         case MTD_OPS_PLACE_OOB:
1844         case MTD_OPS_AUTO_OOB:
1845         case MTD_OPS_RAW:
1846                 break;
1847
1848         default:
1849                 goto out;
1850         }
1851
1852         if (!ops->datbuf)
1853                 ret = nand_do_read_oob(mtd, from, ops);
1854         else
1855                 ret = nand_do_read_ops(mtd, from, ops);
1856
1857 out:
1858         nand_release_device(mtd);
1859         return ret;
1860 }
1861
1862
1863 /**
1864  * nand_write_page_raw - [INTERN] raw page write function
1865  * @mtd: mtd info structure
1866  * @chip: nand chip info structure
1867  * @buf: data buffer
1868  * @oob_required: must write chip->oob_poi to OOB
1869  *
1870  * Not for syndrome calculating ECC controllers, which use a special oob layout.
1871  */
1872 static int nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1873                                 const uint8_t *buf, int oob_required)
1874 {
1875         chip->write_buf(mtd, buf, mtd->writesize);
1876         if (oob_required)
1877                 chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1878
1879         return 0;
1880 }
1881
1882 /**
1883  * nand_write_page_raw_syndrome - [INTERN] raw page write function
1884  * @mtd: mtd info structure
1885  * @chip: nand chip info structure
1886  * @buf: data buffer
1887  * @oob_required: must write chip->oob_poi to OOB
1888  *
1889  * We need a special oob layout and handling even when ECC isn't checked.
1890  */
1891 static int nand_write_page_raw_syndrome(struct mtd_info *mtd,
1892                                         struct nand_chip *chip,
1893                                         const uint8_t *buf, int oob_required)
1894 {
1895         int eccsize = chip->ecc.size;
1896         int eccbytes = chip->ecc.bytes;
1897         uint8_t *oob = chip->oob_poi;
1898         int steps, size;
1899
1900         for (steps = chip->ecc.steps; steps > 0; steps--) {
1901                 chip->write_buf(mtd, buf, eccsize);
1902                 buf += eccsize;
1903
1904                 if (chip->ecc.prepad) {
1905                         chip->write_buf(mtd, oob, chip->ecc.prepad);
1906                         oob += chip->ecc.prepad;
1907                 }
1908
1909                 chip->read_buf(mtd, oob, eccbytes);
1910                 oob += eccbytes;
1911
1912                 if (chip->ecc.postpad) {
1913                         chip->write_buf(mtd, oob, chip->ecc.postpad);
1914                         oob += chip->ecc.postpad;
1915                 }
1916         }
1917
1918         size = mtd->oobsize - (oob - chip->oob_poi);
1919         if (size)
1920                 chip->write_buf(mtd, oob, size);
1921
1922         return 0;
1923 }
1924 /**
1925  * nand_write_page_swecc - [REPLACEABLE] software ECC based page write function
1926  * @mtd: mtd info structure
1927  * @chip: nand chip info structure
1928  * @buf: data buffer
1929  * @oob_required: must write chip->oob_poi to OOB
1930  */
1931 static int nand_write_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
1932                                   const uint8_t *buf, int oob_required)
1933 {
1934         int i, eccsize = chip->ecc.size;
1935         int eccbytes = chip->ecc.bytes;
1936         int eccsteps = chip->ecc.steps;
1937         uint8_t *ecc_calc = chip->buffers->ecccalc;
1938         const uint8_t *p = buf;
1939         uint32_t *eccpos = chip->ecc.layout->eccpos;
1940
1941         /* Software ECC calculation */
1942         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
1943                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1944
1945         for (i = 0; i < chip->ecc.total; i++)
1946                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1947
1948         return chip->ecc.write_page_raw(mtd, chip, buf, 1);
1949 }
1950
1951 /**
1952  * nand_write_page_hwecc - [REPLACEABLE] hardware ECC based page write function
1953  * @mtd: mtd info structure
1954  * @chip: nand chip info structure
1955  * @buf: data buffer
1956  * @oob_required: must write chip->oob_poi to OOB
1957  */
1958 static int nand_write_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
1959                                   const uint8_t *buf, int oob_required)
1960 {
1961         int i, eccsize = chip->ecc.size;
1962         int eccbytes = chip->ecc.bytes;
1963         int eccsteps = chip->ecc.steps;
1964         uint8_t *ecc_calc = chip->buffers->ecccalc;
1965         const uint8_t *p = buf;
1966         uint32_t *eccpos = chip->ecc.layout->eccpos;
1967
1968         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1969                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1970                 chip->write_buf(mtd, p, eccsize);
1971                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1972         }
1973
1974         for (i = 0; i < chip->ecc.total; i++)
1975                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1976
1977         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1978
1979         return 0;
1980 }
1981
1982 /**
1983  * nand_write_page_syndrome - [REPLACEABLE] hardware ECC syndrome based page write
1984  * @mtd: mtd info structure
1985  * @chip: nand chip info structure
1986  * @buf: data buffer
1987  * @oob_required: must write chip->oob_poi to OOB
1988  *
1989  * The hw generator calculates the error syndrome automatically. Therefore we
1990  * need a special oob layout and handling.
1991  */
1992 static int nand_write_page_syndrome(struct mtd_info *mtd,
1993                                     struct nand_chip *chip,
1994                                     const uint8_t *buf, int oob_required)
1995 {
1996         int i, eccsize = chip->ecc.size;
1997         int eccbytes = chip->ecc.bytes;
1998         int eccsteps = chip->ecc.steps;
1999         const uint8_t *p = buf;
2000         uint8_t *oob = chip->oob_poi;
2001
2002         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
2003
2004                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
2005                 chip->write_buf(mtd, p, eccsize);
2006
2007                 if (chip->ecc.prepad) {
2008                         chip->write_buf(mtd, oob, chip->ecc.prepad);
2009                         oob += chip->ecc.prepad;
2010                 }
2011
2012                 chip->ecc.calculate(mtd, p, oob);
2013                 chip->write_buf(mtd, oob, eccbytes);
2014                 oob += eccbytes;
2015
2016                 if (chip->ecc.postpad) {
2017                         chip->write_buf(mtd, oob, chip->ecc.postpad);
2018                         oob += chip->ecc.postpad;
2019                 }
2020         }
2021
2022         /* Calculate remaining oob bytes */
2023         i = mtd->oobsize - (oob - chip->oob_poi);
2024         if (i)
2025                 chip->write_buf(mtd, oob, i);
2026
2027         return 0;
2028 }
2029
2030 /**
2031  * nand_write_page - [REPLACEABLE] write one page
2032  * @mtd: MTD device structure
2033  * @chip: NAND chip descriptor
2034  * @buf: the data to write
2035  * @oob_required: must write chip->oob_poi to OOB
2036  * @page: page number to write
2037  * @cached: cached programming
2038  * @raw: use _raw version of write_page
2039  */
2040 static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
2041                            const uint8_t *buf, int oob_required, int page,
2042                            int cached, int raw)
2043 {
2044         int status;
2045
2046         chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
2047
2048         if (unlikely(raw))
2049                 status = chip->ecc.write_page_raw(mtd, chip, buf, oob_required);
2050         else
2051                 status = chip->ecc.write_page(mtd, chip, buf, oob_required);
2052
2053         if (status < 0)
2054                 return status;
2055
2056         /*
2057          * Cached progamming disabled for now. Not sure if it's worth the
2058          * trouble. The speed gain is not very impressive. (2.3->2.6Mib/s).
2059          */
2060         cached = 0;
2061
2062         if (!cached || !(chip->options & NAND_CACHEPRG)) {
2063
2064                 chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
2065                 status = chip->waitfunc(mtd, chip);
2066                 /*
2067                  * See if operation failed and additional status checks are
2068                  * available.
2069                  */
2070                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2071                         status = chip->errstat(mtd, chip, FL_WRITING, status,
2072                                                page);
2073
2074                 if (status & NAND_STATUS_FAIL)
2075                         return -EIO;
2076         } else {
2077                 chip->cmdfunc(mtd, NAND_CMD_CACHEDPROG, -1, -1);
2078                 status = chip->waitfunc(mtd, chip);
2079         }
2080
2081         return 0;
2082 }
2083
2084 /**
2085  * nand_fill_oob - [INTERN] Transfer client buffer to oob
2086  * @mtd: MTD device structure
2087  * @oob: oob data buffer
2088  * @len: oob data write length
2089  * @ops: oob ops structure
2090  */
2091 static uint8_t *nand_fill_oob(struct mtd_info *mtd, uint8_t *oob, size_t len,
2092                               struct mtd_oob_ops *ops)
2093 {
2094         struct nand_chip *chip = mtd->priv;
2095
2096         /*
2097          * Initialise to all 0xFF, to avoid the possibility of left over OOB
2098          * data from a previous OOB read.
2099          */
2100         memset(chip->oob_poi, 0xff, mtd->oobsize);
2101
2102         switch (ops->mode) {
2103
2104         case MTD_OPS_PLACE_OOB:
2105         case MTD_OPS_RAW:
2106                 memcpy(chip->oob_poi + ops->ooboffs, oob, len);
2107                 return oob + len;
2108
2109         case MTD_OPS_AUTO_OOB: {
2110                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
2111                 uint32_t boffs = 0, woffs = ops->ooboffs;
2112                 size_t bytes = 0;
2113
2114                 for (; free->length && len; free++, len -= bytes) {
2115                         /* Write request not from offset 0? */
2116                         if (unlikely(woffs)) {
2117                                 if (woffs >= free->length) {
2118                                         woffs -= free->length;
2119                                         continue;
2120                                 }
2121                                 boffs = free->offset + woffs;
2122                                 bytes = min_t(size_t, len,
2123                                               (free->length - woffs));
2124                                 woffs = 0;
2125                         } else {
2126                                 bytes = min_t(size_t, len, free->length);
2127                                 boffs = free->offset;
2128                         }
2129                         memcpy(chip->oob_poi + boffs, oob, bytes);
2130                         oob += bytes;
2131                 }
2132                 return oob;
2133         }
2134         default:
2135                 BUG();
2136         }
2137         return NULL;
2138 }
2139
2140 #define NOTALIGNED(x)   ((x & (chip->subpagesize - 1)) != 0)
2141
2142 /**
2143  * nand_do_write_ops - [INTERN] NAND write with ECC
2144  * @mtd: MTD device structure
2145  * @to: offset to write to
2146  * @ops: oob operations description structure
2147  *
2148  * NAND write with ECC.
2149  */
2150 static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
2151                              struct mtd_oob_ops *ops)
2152 {
2153         int chipnr, realpage, page, blockmask, column;
2154         struct nand_chip *chip = mtd->priv;
2155         uint32_t writelen = ops->len;
2156
2157         uint32_t oobwritelen = ops->ooblen;
2158         uint32_t oobmaxlen = ops->mode == MTD_OPS_AUTO_OOB ?
2159                                 mtd->oobavail : mtd->oobsize;
2160
2161         uint8_t *oob = ops->oobbuf;
2162         uint8_t *buf = ops->datbuf;
2163         int ret, subpage;
2164         int oob_required = oob ? 1 : 0;
2165
2166         ops->retlen = 0;
2167         if (!writelen)
2168                 return 0;
2169
2170         /* Reject writes, which are not page aligned */
2171         if (NOTALIGNED(to) || NOTALIGNED(ops->len)) {
2172                 pr_notice("%s: attempt to write non page aligned data\n",
2173                            __func__);
2174                 return -EINVAL;
2175         }
2176
2177         column = to & (mtd->writesize - 1);
2178         subpage = column || (writelen & (mtd->writesize - 1));
2179
2180         if (subpage && oob)
2181                 return -EINVAL;
2182
2183         chipnr = (int)(to >> chip->chip_shift);
2184         chip->select_chip(mtd, chipnr);
2185
2186         /* Check, if it is write protected */
2187         if (nand_check_wp(mtd)) {
2188                 ret = -EIO;
2189                 goto err_out;
2190         }
2191
2192         realpage = (int)(to >> chip->page_shift);
2193         page = realpage & chip->pagemask;
2194         blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
2195
2196         /* Invalidate the page cache, when we write to the cached page */
2197         if (to <= (chip->pagebuf << chip->page_shift) &&
2198             (chip->pagebuf << chip->page_shift) < (to + ops->len))
2199                 chip->pagebuf = -1;
2200
2201         /* Don't allow multipage oob writes with offset */
2202         if (oob && ops->ooboffs && (ops->ooboffs + ops->ooblen > oobmaxlen)) {
2203                 ret = -EINVAL;
2204                 goto err_out;
2205         }
2206
2207         while (1) {
2208                 int bytes = mtd->writesize;
2209                 int cached = writelen > bytes && page != blockmask;
2210                 uint8_t *wbuf = buf;
2211
2212                 /* Partial page write? */
2213                 if (unlikely(column || writelen < (mtd->writesize - 1))) {
2214                         cached = 0;
2215                         bytes = min_t(int, bytes - column, (int) writelen);
2216                         chip->pagebuf = -1;
2217                         memset(chip->buffers->databuf, 0xff, mtd->writesize);
2218                         memcpy(&chip->buffers->databuf[column], buf, bytes);
2219                         wbuf = chip->buffers->databuf;
2220                 }
2221
2222                 if (unlikely(oob)) {
2223                         size_t len = min(oobwritelen, oobmaxlen);
2224                         oob = nand_fill_oob(mtd, oob, len, ops);
2225                         oobwritelen -= len;
2226                 } else {
2227                         /* We still need to erase leftover OOB data */
2228                         memset(chip->oob_poi, 0xff, mtd->oobsize);
2229                 }
2230
2231                 ret = chip->write_page(mtd, chip, wbuf, oob_required, page,
2232                                        cached, (ops->mode == MTD_OPS_RAW));
2233                 if (ret)
2234                         break;
2235
2236                 writelen -= bytes;
2237                 if (!writelen)
2238                         break;
2239
2240                 column = 0;
2241                 buf += bytes;
2242                 realpage++;
2243
2244                 page = realpage & chip->pagemask;
2245                 /* Check, if we cross a chip boundary */
2246                 if (!page) {
2247                         chipnr++;
2248                         chip->select_chip(mtd, -1);
2249                         chip->select_chip(mtd, chipnr);
2250                 }
2251         }
2252
2253         ops->retlen = ops->len - writelen;
2254         if (unlikely(oob))
2255                 ops->oobretlen = ops->ooblen;
2256
2257 err_out:
2258         chip->select_chip(mtd, -1);
2259         return ret;
2260 }
2261
2262 /**
2263  * panic_nand_write - [MTD Interface] NAND write with ECC
2264  * @mtd: MTD device structure
2265  * @to: offset to write to
2266  * @len: number of bytes to write
2267  * @retlen: pointer to variable to store the number of written bytes
2268  * @buf: the data to write
2269  *
2270  * NAND write with ECC. Used when performing writes in interrupt context, this
2271  * may for example be called by mtdoops when writing an oops while in panic.
2272  */
2273 static int panic_nand_write(struct mtd_info *mtd, loff_t to, size_t len,
2274                             size_t *retlen, const uint8_t *buf)
2275 {
2276         struct nand_chip *chip = mtd->priv;
2277         struct mtd_oob_ops ops;
2278         int ret;
2279
2280         /* Wait for the device to get ready */
2281         panic_nand_wait(mtd, chip, 400);
2282
2283         /* Grab the device */
2284         panic_nand_get_device(chip, mtd, FL_WRITING);
2285
2286         ops.len = len;
2287         ops.datbuf = (uint8_t *)buf;
2288         ops.oobbuf = NULL;
2289         ops.mode = MTD_OPS_PLACE_OOB;
2290
2291         ret = nand_do_write_ops(mtd, to, &ops);
2292
2293         *retlen = ops.retlen;
2294         return ret;
2295 }
2296
2297 /**
2298  * nand_write - [MTD Interface] NAND write with ECC
2299  * @mtd: MTD device structure
2300  * @to: offset to write to
2301  * @len: number of bytes to write
2302  * @retlen: pointer to variable to store the number of written bytes
2303  * @buf: the data to write
2304  *
2305  * NAND write with ECC.
2306  */
2307 static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
2308                           size_t *retlen, const uint8_t *buf)
2309 {
2310         struct mtd_oob_ops ops;
2311         int ret;
2312
2313         nand_get_device(mtd, FL_WRITING);
2314         ops.len = len;
2315         ops.datbuf = (uint8_t *)buf;
2316         ops.oobbuf = NULL;
2317         ops.mode = MTD_OPS_PLACE_OOB;
2318         ret = nand_do_write_ops(mtd, to, &ops);
2319         *retlen = ops.retlen;
2320         nand_release_device(mtd);
2321         return ret;
2322 }
2323
2324 /**
2325  * nand_do_write_oob - [MTD Interface] NAND write out-of-band
2326  * @mtd: MTD device structure
2327  * @to: offset to write to
2328  * @ops: oob operation description structure
2329  *
2330  * NAND write out-of-band.
2331  */
2332 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
2333                              struct mtd_oob_ops *ops)
2334 {
2335         int chipnr, page, status, len;
2336         struct nand_chip *chip = mtd->priv;
2337
2338         pr_debug("%s: to = 0x%08x, len = %i\n",
2339                          __func__, (unsigned int)to, (int)ops->ooblen);
2340
2341         if (ops->mode == MTD_OPS_AUTO_OOB)
2342                 len = chip->ecc.layout->oobavail;
2343         else
2344                 len = mtd->oobsize;
2345
2346         /* Do not allow write past end of page */
2347         if ((ops->ooboffs + ops->ooblen) > len) {
2348                 pr_debug("%s: attempt to write past end of page\n",
2349                                 __func__);
2350                 return -EINVAL;
2351         }
2352
2353         if (unlikely(ops->ooboffs >= len)) {
2354                 pr_debug("%s: attempt to start write outside oob\n",
2355                                 __func__);
2356                 return -EINVAL;
2357         }
2358
2359         /* Do not allow write past end of device */
2360         if (unlikely(to >= mtd->size ||
2361                      ops->ooboffs + ops->ooblen >
2362                         ((mtd->size >> chip->page_shift) -
2363                          (to >> chip->page_shift)) * len)) {
2364                 pr_debug("%s: attempt to write beyond end of device\n",
2365                                 __func__);
2366                 return -EINVAL;
2367         }
2368
2369         chipnr = (int)(to >> chip->chip_shift);
2370         chip->select_chip(mtd, chipnr);
2371
2372         /* Shift to get page */
2373         page = (int)(to >> chip->page_shift);
2374
2375         /*
2376          * Reset the chip. Some chips (like the Toshiba TC5832DC found in one
2377          * of my DiskOnChip 2000 test units) will clear the whole data page too
2378          * if we don't do this. I have no clue why, but I seem to have 'fixed'
2379          * it in the doc2000 driver in August 1999.  dwmw2.
2380          */
2381         chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
2382
2383         /* Check, if it is write protected */
2384         if (nand_check_wp(mtd)) {
2385                 chip->select_chip(mtd, -1);
2386                 return -EROFS;
2387         }
2388
2389         /* Invalidate the page cache, if we write to the cached page */
2390         if (page == chip->pagebuf)
2391                 chip->pagebuf = -1;
2392
2393         nand_fill_oob(mtd, ops->oobbuf, ops->ooblen, ops);
2394
2395         if (ops->mode == MTD_OPS_RAW)
2396                 status = chip->ecc.write_oob_raw(mtd, chip, page & chip->pagemask);
2397         else
2398                 status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
2399
2400         chip->select_chip(mtd, -1);
2401
2402         if (status)
2403                 return status;
2404
2405         ops->oobretlen = ops->ooblen;
2406
2407         return 0;
2408 }
2409
2410 /**
2411  * nand_write_oob - [MTD Interface] NAND write data and/or out-of-band
2412  * @mtd: MTD device structure
2413  * @to: offset to write to
2414  * @ops: oob operation description structure
2415  */
2416 static int nand_write_oob(struct mtd_info *mtd, loff_t to,
2417                           struct mtd_oob_ops *ops)
2418 {
2419         int ret = -ENOTSUPP;
2420
2421         ops->retlen = 0;
2422
2423         /* Do not allow writes past end of device */
2424         if (ops->datbuf && (to + ops->len) > mtd->size) {
2425                 pr_debug("%s: attempt to write beyond end of device\n",
2426                                 __func__);
2427                 return -EINVAL;
2428         }
2429
2430         nand_get_device(mtd, FL_WRITING);
2431
2432         switch (ops->mode) {
2433         case MTD_OPS_PLACE_OOB:
2434         case MTD_OPS_AUTO_OOB:
2435         case MTD_OPS_RAW:
2436                 break;
2437
2438         default:
2439                 goto out;
2440         }
2441
2442         if (!ops->datbuf)
2443                 ret = nand_do_write_oob(mtd, to, ops);
2444         else
2445                 ret = nand_do_write_ops(mtd, to, ops);
2446
2447 out:
2448         nand_release_device(mtd);
2449         return ret;
2450 }
2451
2452 /**
2453  * single_erase_cmd - [GENERIC] NAND standard block erase command function
2454  * @mtd: MTD device structure
2455  * @page: the page address of the block which will be erased
2456  *
2457  * Standard erase command for NAND chips.
2458  */
2459 static void single_erase_cmd(struct mtd_info *mtd, int page)
2460 {
2461         struct nand_chip *chip = mtd->priv;
2462         /* Send commands to erase a block */
2463         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
2464         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
2465 }
2466
2467 /**
2468  * multi_erase_cmd - [GENERIC] AND specific block erase command function
2469  * @mtd: MTD device structure
2470  * @page: the page address of the block which will be erased
2471  *
2472  * AND multi block erase command function. Erase 4 consecutive blocks.
2473  */
2474 static void multi_erase_cmd(struct mtd_info *mtd, int page)
2475 {
2476         struct nand_chip *chip = mtd->priv;
2477         /* Send commands to erase a block */
2478         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
2479         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
2480         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
2481         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
2482         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
2483 }
2484
2485 /**
2486  * nand_erase - [MTD Interface] erase block(s)
2487  * @mtd: MTD device structure
2488  * @instr: erase instruction
2489  *
2490  * Erase one ore more blocks.
2491  */
2492 static int nand_erase(struct mtd_info *mtd, struct erase_info *instr)
2493 {
2494         return nand_erase_nand(mtd, instr, 0);
2495 }
2496
2497 #define BBT_PAGE_MASK   0xffffff3f
2498 /**
2499  * nand_erase_nand - [INTERN] erase block(s)
2500  * @mtd: MTD device structure
2501  * @instr: erase instruction
2502  * @allowbbt: allow erasing the bbt area
2503  *
2504  * Erase one ore more blocks.
2505  */
2506 int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
2507                     int allowbbt)
2508 {
2509         int page, status, pages_per_block, ret, chipnr;
2510         struct nand_chip *chip = mtd->priv;
2511         loff_t rewrite_bbt[NAND_MAX_CHIPS] = {0};
2512         unsigned int bbt_masked_page = 0xffffffff;
2513         loff_t len;
2514
2515         pr_debug("%s: start = 0x%012llx, len = %llu\n",
2516                         __func__, (unsigned long long)instr->addr,
2517                         (unsigned long long)instr->len);
2518
2519         if (check_offs_len(mtd, instr->addr, instr->len))
2520                 return -EINVAL;
2521
2522         /* Grab the lock and see if the device is available */
2523         nand_get_device(mtd, FL_ERASING);
2524
2525         /* Shift to get first page */
2526         page = (int)(instr->addr >> chip->page_shift);
2527         chipnr = (int)(instr->addr >> chip->chip_shift);
2528
2529         /* Calculate pages in each block */
2530         pages_per_block = 1 << (chip->phys_erase_shift - chip->page_shift);
2531
2532         /* Select the NAND device */
2533         chip->select_chip(mtd, chipnr);
2534
2535         /* Check, if it is write protected */
2536         if (nand_check_wp(mtd)) {
2537                 pr_debug("%s: device is write protected!\n",
2538                                 __func__);
2539                 instr->state = MTD_ERASE_FAILED;
2540                 goto erase_exit;
2541         }
2542
2543         /*
2544          * If BBT requires refresh, set the BBT page mask to see if the BBT
2545          * should be rewritten. Otherwise the mask is set to 0xffffffff which
2546          * can not be matched. This is also done when the bbt is actually
2547          * erased to avoid recursive updates.
2548          */
2549         if (chip->options & BBT_AUTO_REFRESH && !allowbbt)
2550                 bbt_masked_page = chip->bbt_td->pages[chipnr] & BBT_PAGE_MASK;
2551
2552         /* Loop through the pages */
2553         len = instr->len;
2554
2555         instr->state = MTD_ERASING;
2556
2557         while (len) {
2558                 /* Check if we have a bad block, we do not erase bad blocks! */
2559                 if (nand_block_checkbad(mtd, ((loff_t) page) <<
2560                                         chip->page_shift, 0, allowbbt)) {
2561                         pr_warn("%s: attempt to erase a bad block at page 0x%08x\n",
2562                                     __func__, page);
2563                         instr->state = MTD_ERASE_FAILED;
2564                         goto erase_exit;
2565                 }
2566
2567                 /*
2568                  * Invalidate the page cache, if we erase the block which
2569                  * contains the current cached page.
2570                  */
2571                 if (page <= chip->pagebuf && chip->pagebuf <
2572                     (page + pages_per_block))
2573                         chip->pagebuf = -1;
2574
2575                 chip->erase_cmd(mtd, page & chip->pagemask);
2576
2577                 status = chip->waitfunc(mtd, chip);
2578
2579                 /*
2580                  * See if operation failed and additional status checks are
2581                  * available
2582                  */
2583                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2584                         status = chip->errstat(mtd, chip, FL_ERASING,
2585                                                status, page);
2586
2587                 /* See if block erase succeeded */
2588                 if (status & NAND_STATUS_FAIL) {
2589                         pr_debug("%s: failed erase, page 0x%08x\n",
2590                                         __func__, page);
2591                         instr->state = MTD_ERASE_FAILED;
2592                         instr->fail_addr =
2593                                 ((loff_t)page << chip->page_shift);
2594                         goto erase_exit;
2595                 }
2596
2597                 /*
2598                  * If BBT requires refresh, set the BBT rewrite flag to the
2599                  * page being erased.
2600                  */
2601                 if (bbt_masked_page != 0xffffffff &&
2602                     (page & BBT_PAGE_MASK) == bbt_masked_page)
2603                             rewrite_bbt[chipnr] =
2604                                         ((loff_t)page << chip->page_shift);
2605
2606                 /* Increment page address and decrement length */
2607                 len -= (1 << chip->phys_erase_shift);
2608                 page += pages_per_block;
2609
2610                 /* Check, if we cross a chip boundary */
2611                 if (len && !(page & chip->pagemask)) {
2612                         chipnr++;
2613                         chip->select_chip(mtd, -1);
2614                         chip->select_chip(mtd, chipnr);
2615
2616                         /*
2617                          * If BBT requires refresh and BBT-PERCHIP, set the BBT
2618                          * page mask to see if this BBT should be rewritten.
2619                          */
2620                         if (bbt_masked_page != 0xffffffff &&
2621                             (chip->bbt_td->options & NAND_BBT_PERCHIP))
2622                                 bbt_masked_page = chip->bbt_td->pages[chipnr] &
2623                                         BBT_PAGE_MASK;
2624                 }
2625         }
2626         instr->state = MTD_ERASE_DONE;
2627
2628 erase_exit:
2629
2630         ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
2631
2632         /* Deselect and wake up anyone waiting on the device */
2633         chip->select_chip(mtd, -1);
2634         nand_release_device(mtd);
2635
2636         /* Do call back function */
2637         if (!ret)
2638                 mtd_erase_callback(instr);
2639
2640         /*
2641          * If BBT requires refresh and erase was successful, rewrite any
2642          * selected bad block tables.
2643          */
2644         if (bbt_masked_page == 0xffffffff || ret)
2645                 return ret;
2646
2647         for (chipnr = 0; chipnr < chip->numchips; chipnr++) {
2648                 if (!rewrite_bbt[chipnr])
2649                         continue;
2650                 /* Update the BBT for chip */
2651                 pr_debug("%s: nand_update_bbt (%d:0x%0llx 0x%0x)\n",
2652                                 __func__, chipnr, rewrite_bbt[chipnr],
2653                                 chip->bbt_td->pages[chipnr]);
2654                 nand_update_bbt(mtd, rewrite_bbt[chipnr]);
2655         }
2656
2657         /* Return more or less happy */
2658         return ret;
2659 }
2660
2661 /**
2662  * nand_sync - [MTD Interface] sync
2663  * @mtd: MTD device structure
2664  *
2665  * Sync is actually a wait for chip ready function.
2666  */
2667 static void nand_sync(struct mtd_info *mtd)
2668 {
2669         pr_debug("%s: called\n", __func__);
2670
2671         /* Grab the lock and see if the device is available */
2672         nand_get_device(mtd, FL_SYNCING);
2673         /* Release it and go back */
2674         nand_release_device(mtd);
2675 }
2676
2677 /**
2678  * nand_block_isbad - [MTD Interface] Check if block at offset is bad
2679  * @mtd: MTD device structure
2680  * @offs: offset relative to mtd start
2681  */
2682 static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
2683 {
2684         return nand_block_checkbad(mtd, offs, 1, 0);
2685 }
2686
2687 /**
2688  * nand_block_markbad - [MTD Interface] Mark block at the given offset as bad
2689  * @mtd: MTD device structure
2690  * @ofs: offset relative to mtd start
2691  */
2692 static int nand_block_markbad(struct mtd_info *mtd, loff_t ofs)
2693 {
2694         struct nand_chip *chip = mtd->priv;
2695         int ret;
2696
2697         ret = nand_block_isbad(mtd, ofs);
2698         if (ret) {
2699                 /* If it was bad already, return success and do nothing */
2700                 if (ret > 0)
2701                         return 0;
2702                 return ret;
2703         }
2704
2705         return chip->block_markbad(mtd, ofs);
2706 }
2707
2708 /**
2709  * nand_onfi_set_features- [REPLACEABLE] set features for ONFI nand
2710  * @mtd: MTD device structure
2711  * @chip: nand chip info structure
2712  * @addr: feature address.
2713  * @subfeature_param: the subfeature parameters, a four bytes array.
2714  */
2715 static int nand_onfi_set_features(struct mtd_info *mtd, struct nand_chip *chip,
2716                         int addr, uint8_t *subfeature_param)
2717 {
2718         int status;
2719
2720         if (!chip->onfi_version)
2721                 return -EINVAL;
2722
2723         chip->cmdfunc(mtd, NAND_CMD_SET_FEATURES, addr, -1);
2724         chip->write_buf(mtd, subfeature_param, ONFI_SUBFEATURE_PARAM_LEN);
2725         status = chip->waitfunc(mtd, chip);
2726         if (status & NAND_STATUS_FAIL)
2727                 return -EIO;
2728         return 0;
2729 }
2730
2731 /**
2732  * nand_onfi_get_features- [REPLACEABLE] get features for ONFI nand
2733  * @mtd: MTD device structure
2734  * @chip: nand chip info structure
2735  * @addr: feature address.
2736  * @subfeature_param: the subfeature parameters, a four bytes array.
2737  */
2738 static int nand_onfi_get_features(struct mtd_info *mtd, struct nand_chip *chip,
2739                         int addr, uint8_t *subfeature_param)
2740 {
2741         if (!chip->onfi_version)
2742                 return -EINVAL;
2743
2744         /* clear the sub feature parameters */
2745         memset(subfeature_param, 0, ONFI_SUBFEATURE_PARAM_LEN);
2746
2747         chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES, addr, -1);
2748         chip->read_buf(mtd, subfeature_param, ONFI_SUBFEATURE_PARAM_LEN);
2749         return 0;
2750 }
2751
2752 /**
2753  * nand_suspend - [MTD Interface] Suspend the NAND flash
2754  * @mtd: MTD device structure
2755  */
2756 static int nand_suspend(struct mtd_info *mtd)
2757 {
2758         return nand_get_device(mtd, FL_PM_SUSPENDED);
2759 }
2760
2761 /**
2762  * nand_resume - [MTD Interface] Resume the NAND flash
2763  * @mtd: MTD device structure
2764  */
2765 static void nand_resume(struct mtd_info *mtd)
2766 {
2767         struct nand_chip *chip = mtd->priv;
2768
2769         if (chip->state == FL_PM_SUSPENDED)
2770                 nand_release_device(mtd);
2771         else
2772                 pr_err("%s called for a chip which is not in suspended state\n",
2773                         __func__);
2774 }
2775
2776 /* Set default functions */
2777 static void nand_set_defaults(struct nand_chip *chip, int busw)
2778 {
2779         /* check for proper chip_delay setup, set 20us if not */
2780         if (!chip->chip_delay)
2781                 chip->chip_delay = 20;
2782
2783         /* check, if a user supplied command function given */
2784         if (chip->cmdfunc == NULL)
2785                 chip->cmdfunc = nand_command;
2786
2787         /* check, if a user supplied wait function given */
2788         if (chip->waitfunc == NULL)
2789                 chip->waitfunc = nand_wait;
2790
2791         if (!chip->select_chip)
2792                 chip->select_chip = nand_select_chip;
2793         if (!chip->read_byte)
2794                 chip->read_byte = busw ? nand_read_byte16 : nand_read_byte;
2795         if (!chip->read_word)
2796                 chip->read_word = nand_read_word;
2797         if (!chip->block_bad)
2798                 chip->block_bad = nand_block_bad;
2799         if (!chip->block_markbad)
2800                 chip->block_markbad = nand_default_block_markbad;
2801         if (!chip->write_buf)
2802                 chip->write_buf = busw ? nand_write_buf16 : nand_write_buf;
2803         if (!chip->read_buf)
2804                 chip->read_buf = busw ? nand_read_buf16 : nand_read_buf;
2805         if (!chip->scan_bbt)
2806                 chip->scan_bbt = nand_default_bbt;
2807
2808         if (!chip->controller) {
2809                 chip->controller = &chip->hwcontrol;
2810                 spin_lock_init(&chip->controller->lock);
2811                 init_waitqueue_head(&chip->controller->wq);
2812         }
2813
2814 }
2815
2816 /* Sanitize ONFI strings so we can safely print them */
2817 static void sanitize_string(uint8_t *s, size_t len)
2818 {
2819         ssize_t i;
2820
2821         /* Null terminate */
2822         s[len - 1] = 0;
2823
2824         /* Remove non printable chars */
2825         for (i = 0; i < len - 1; i++) {
2826                 if (s[i] < ' ' || s[i] > 127)
2827                         s[i] = '?';
2828         }
2829
2830         /* Remove trailing spaces */
2831         strim(s);
2832 }
2833
2834 static u16 onfi_crc16(u16 crc, u8 const *p, size_t len)
2835 {
2836         int i;
2837         while (len--) {
2838                 crc ^= *p++ << 8;
2839                 for (i = 0; i < 8; i++)
2840                         crc = (crc << 1) ^ ((crc & 0x8000) ? 0x8005 : 0);
2841         }
2842
2843         return crc;
2844 }
2845
2846 /*
2847  * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
2848  */
2849 static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip,
2850                                         int *busw)
2851 {
2852         struct nand_onfi_params *p = &chip->onfi_params;
2853         int i;
2854         int val;
2855
2856         /* ONFI need to be probed in 8 bits mode, and 16 bits should be selected with NAND_BUSWIDTH_AUTO */
2857         if (chip->options & NAND_BUSWIDTH_16) {
2858                 pr_err("Trying ONFI probe in 16 bits mode, aborting !\n");
2859                 return 0;
2860         }
2861         /* Try ONFI for unknown chip or LP */
2862         chip->cmdfunc(mtd, NAND_CMD_READID, 0x20, -1);
2863         if (chip->read_byte(mtd) != 'O' || chip->read_byte(mtd) != 'N' ||
2864                 chip->read_byte(mtd) != 'F' || chip->read_byte(mtd) != 'I')
2865                 return 0;
2866
2867         chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);
2868         for (i = 0; i < 3; i++) {
2869                 chip->read_buf(mtd, (uint8_t *)p, sizeof(*p));
2870                 if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 254) ==
2871                                 le16_to_cpu(p->crc)) {
2872                         pr_info("ONFI param page %d valid\n", i);
2873                         break;
2874                 }
2875         }
2876
2877         if (i == 3)
2878                 return 0;
2879
2880         /* Check version */
2881         val = le16_to_cpu(p->revision);
2882         if (val & (1 << 5))
2883                 chip->onfi_version = 23;
2884         else if (val & (1 << 4))
2885                 chip->onfi_version = 22;
2886         else if (val & (1 << 3))
2887                 chip->onfi_version = 21;
2888         else if (val & (1 << 2))
2889                 chip->onfi_version = 20;
2890         else if (val & (1 << 1))
2891                 chip->onfi_version = 10;
2892         else
2893                 chip->onfi_version = 0;
2894
2895         if (!chip->onfi_version) {
2896                 pr_info("%s: unsupported ONFI version: %d\n", __func__, val);
2897                 return 0;
2898         }
2899
2900         sanitize_string(p->manufacturer, sizeof(p->manufacturer));
2901         sanitize_string(p->model, sizeof(p->model));
2902         if (!mtd->name)
2903                 mtd->name = p->model;
2904         mtd->writesize = le32_to_cpu(p->byte_per_page);
2905         mtd->erasesize = le32_to_cpu(p->pages_per_block) * mtd->writesize;
2906         mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
2907         chip->chipsize = le32_to_cpu(p->blocks_per_lun);
2908         chip->chipsize *= (uint64_t)mtd->erasesize * p->lun_count;
2909         *busw = 0;
2910         if (le16_to_cpu(p->features) & 1)
2911                 *busw = NAND_BUSWIDTH_16;
2912
2913         pr_info("ONFI flash detected\n");
2914         return 1;
2915 }
2916
2917 /*
2918  * nand_id_has_period - Check if an ID string has a given wraparound period
2919  * @id_data: the ID string
2920  * @arrlen: the length of the @id_data array
2921  * @period: the period of repitition
2922  *
2923  * Check if an ID string is repeated within a given sequence of bytes at
2924  * specific repetition interval period (e.g., {0x20,0x01,0x7F,0x20} has a
2925  * period of 3). This is a helper function for nand_id_len(). Returns non-zero
2926  * if the repetition has a period of @period; otherwise, returns zero.
2927  */
2928 static int nand_id_has_period(u8 *id_data, int arrlen, int period)
2929 {
2930         int i, j;
2931         for (i = 0; i < period; i++)
2932                 for (j = i + period; j < arrlen; j += period)
2933                         if (id_data[i] != id_data[j])
2934                                 return 0;
2935         return 1;
2936 }
2937
2938 /*
2939  * nand_id_len - Get the length of an ID string returned by CMD_READID
2940  * @id_data: the ID string
2941  * @arrlen: the length of the @id_data array
2942
2943  * Returns the length of the ID string, according to known wraparound/trailing
2944  * zero patterns. If no pattern exists, returns the length of the array.
2945  */
2946 static int nand_id_len(u8 *id_data, int arrlen)
2947 {
2948         int last_nonzero, period;
2949
2950         /* Find last non-zero byte */
2951         for (last_nonzero = arrlen - 1; last_nonzero >= 0; last_nonzero--)
2952                 if (id_data[last_nonzero])
2953                         break;
2954
2955         /* All zeros */
2956         if (last_nonzero < 0)
2957                 return 0;
2958
2959         /* Calculate wraparound period */
2960         for (period = 1; period < arrlen; period++)
2961                 if (nand_id_has_period(id_data, arrlen, period))
2962                         break;
2963
2964         /* There's a repeated pattern */
2965         if (period < arrlen)
2966                 return period;
2967
2968         /* There are trailing zeros */
2969         if (last_nonzero < arrlen - 1)
2970                 return last_nonzero + 1;
2971
2972         /* No pattern detected */
2973         return arrlen;
2974 }
2975
2976 /*
2977  * Many new NAND share similar device ID codes, which represent the size of the
2978  * chip. The rest of the parameters must be decoded according to generic or
2979  * manufacturer-specific "extended ID" decoding patterns.
2980  */
2981 static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip,
2982                                 u8 id_data[8], int *busw)
2983 {
2984         int extid, id_len;
2985         /* The 3rd id byte holds MLC / multichip data */
2986         chip->cellinfo = id_data[2];
2987         /* The 4th id byte is the important one */
2988         extid = id_data[3];
2989
2990         id_len = nand_id_len(id_data, 8);
2991
2992         /*
2993          * Field definitions are in the following datasheets:
2994          * Old style (4,5 byte ID): Samsung K9GAG08U0M (p.32)
2995          * New Samsung (6 byte ID): Samsung K9GAG08U0F (p.44)
2996          * Hynix MLC   (6 byte ID): Hynix H27UBG8T2B (p.22)
2997          *
2998          * Check for ID length, non-zero 6th byte, cell type, and Hynix/Samsung
2999          * ID to decide what to do.
3000          */
3001         if (id_len == 6 && id_data[0] == NAND_MFR_SAMSUNG &&
3002                         (chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
3003                         id_data[5] != 0x00) {
3004                 /* Calc pagesize */
3005                 mtd->writesize = 2048 << (extid & 0x03);
3006                 extid >>= 2;
3007                 /* Calc oobsize */
3008                 switch (((extid >> 2) & 0x04) | (extid & 0x03)) {
3009                 case 1:
3010                         mtd->oobsize = 128;
3011                         break;
3012                 case 2:
3013                         mtd->oobsize = 218;
3014                         break;
3015                 case 3:
3016                         mtd->oobsize = 400;
3017                         break;
3018                 case 4:
3019                         mtd->oobsize = 436;
3020                         break;
3021                 case 5:
3022                         mtd->oobsize = 512;
3023                         break;
3024                 case 6:
3025                 default: /* Other cases are "reserved" (unknown) */
3026                         mtd->oobsize = 640;
3027                         break;
3028                 }
3029                 extid >>= 2;
3030                 /* Calc blocksize */
3031                 mtd->erasesize = (128 * 1024) <<
3032                         (((extid >> 1) & 0x04) | (extid & 0x03));
3033                 *busw = 0;
3034         } else if (id_len == 6 && id_data[0] == NAND_MFR_HYNIX &&
3035                         (chip->cellinfo & NAND_CI_CELLTYPE_MSK)) {
3036                 unsigned int tmp;
3037
3038                 /* Calc pagesize */
3039                 mtd->writesize = 2048 << (extid & 0x03);
3040                 extid >>= 2;
3041                 /* Calc oobsize */
3042                 switch (((extid >> 2) & 0x04) | (extid & 0x03)) {
3043                 case 0:
3044                         mtd->oobsize = 128;
3045                         break;
3046                 case 1:
3047                         mtd->oobsize = 224;
3048                         break;
3049                 case 2:
3050                         mtd->oobsize = 448;
3051                         break;
3052                 case 3:
3053                         mtd->oobsize = 64;
3054                         break;
3055                 case 4:
3056                         mtd->oobsize = 32;
3057                         break;
3058                 case 5:
3059                         mtd->oobsize = 16;
3060                         break;
3061                 default:
3062                         mtd->oobsize = 640;
3063                         break;
3064                 }
3065                 extid >>= 2;
3066                 /* Calc blocksize */
3067                 tmp = ((extid >> 1) & 0x04) | (extid & 0x03);
3068                 if (tmp < 0x03)
3069                         mtd->erasesize = (128 * 1024) << tmp;
3070                 else if (tmp == 0x03)
3071                         mtd->erasesize = 768 * 1024;
3072                 else
3073                         mtd->erasesize = (64 * 1024) << tmp;
3074                 *busw = 0;
3075         } else {
3076                 /* Calc pagesize */
3077                 mtd->writesize = 1024 << (extid & 0x03);
3078                 extid >>= 2;
3079                 /* Calc oobsize */
3080                 mtd->oobsize = (8 << (extid & 0x01)) *
3081                         (mtd->writesize >> 9);
3082                 extid >>= 2;
3083                 /* Calc blocksize. Blocksize is multiples of 64KiB */
3084                 mtd->erasesize = (64 * 1024) << (extid & 0x03);
3085                 extid >>= 2;
3086                 /* Get buswidth information */
3087                 *busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
3088         }
3089 }
3090
3091 /*
3092  * Old devices have chip data hardcoded in the device ID table. nand_decode_id
3093  * decodes a matching ID table entry and assigns the MTD size parameters for
3094  * the chip.
3095  */
3096 static void nand_decode_id(struct mtd_info *mtd, struct nand_chip *chip,
3097                                 struct nand_flash_dev *type, u8 id_data[8],
3098                                 int *busw)
3099 {
3100         int maf_id = id_data[0];
3101
3102         mtd->erasesize = type->erasesize;
3103         mtd->writesize = type->pagesize;
3104         mtd->oobsize = mtd->writesize / 32;
3105         *busw = type->options & NAND_BUSWIDTH_16;
3106
3107         /*
3108          * Check for Spansion/AMD ID + repeating 5th, 6th byte since
3109          * some Spansion chips have erasesize that conflicts with size
3110          * listed in nand_ids table.
3111          * Data sheet (5 byte ID): Spansion S30ML-P ORNAND (p.39)
3112          */
3113         if (maf_id == NAND_MFR_AMD && id_data[4] != 0x00 && id_data[5] == 0x00
3114                         && id_data[6] == 0x00 && id_data[7] == 0x00
3115                         && mtd->writesize == 512) {
3116                 mtd->erasesize = 128 * 1024;
3117                 mtd->erasesize <<= ((id_data[3] & 0x03) << 1);
3118         }
3119 }
3120
3121 /*
3122  * Set the bad block marker/indicator (BBM/BBI) patterns according to some
3123  * heuristic patterns using various detected parameters (e.g., manufacturer,
3124  * page size, cell-type information).
3125  */
3126 static void nand_decode_bbm_options(struct mtd_info *mtd,
3127                                     struct nand_chip *chip, u8 id_data[8])
3128 {
3129         int maf_id = id_data[0];
3130
3131         /* Set the bad block position */
3132         if (mtd->writesize > 512 || (chip->options & NAND_BUSWIDTH_16))
3133                 chip->badblockpos = NAND_LARGE_BADBLOCK_POS;
3134         else
3135                 chip->badblockpos = NAND_SMALL_BADBLOCK_POS;
3136
3137         /*
3138          * Bad block marker is stored in the last page of each block on Samsung
3139          * and Hynix MLC devices; stored in first two pages of each block on
3140          * Micron devices with 2KiB pages and on SLC Samsung, Hynix, Toshiba,
3141          * AMD/Spansion, and Macronix.  All others scan only the first page.
3142          */
3143         if ((chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
3144                         (maf_id == NAND_MFR_SAMSUNG ||
3145                          maf_id == NAND_MFR_HYNIX))
3146                 chip->bbt_options |= NAND_BBT_SCANLASTPAGE;
3147         else if ((!(chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
3148                                 (maf_id == NAND_MFR_SAMSUNG ||
3149                                  maf_id == NAND_MFR_HYNIX ||
3150                                  maf_id == NAND_MFR_TOSHIBA ||
3151                                  maf_id == NAND_MFR_AMD ||
3152                                  maf_id == NAND_MFR_MACRONIX)) ||
3153                         (mtd->writesize == 2048 &&
3154                          maf_id == NAND_MFR_MICRON))
3155                 chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;
3156 }
3157
3158 /*
3159  * Get the flash and manufacturer id and lookup if the type is supported.
3160  */
3161 static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
3162                                                   struct nand_chip *chip,
3163                                                   int busw,
3164                                                   int *maf_id, int *dev_id,
3165                                                   struct nand_flash_dev *type)
3166 {
3167         int i, maf_idx;
3168         u8 id_data[8];
3169
3170         /* Select the device */
3171         chip->select_chip(mtd, 0);
3172
3173         /*
3174          * Reset the chip, required by some chips (e.g. Micron MT29FxGxxxxx)
3175          * after power-up.
3176          */
3177         chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
3178
3179         /* Send the command for reading device ID */
3180         chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
3181
3182         /* Read manufacturer and device IDs */
3183         *maf_id = chip->read_byte(mtd);
3184         *dev_id = chip->read_byte(mtd);
3185
3186         /*
3187          * Try again to make sure, as some systems the bus-hold or other
3188          * interface concerns can cause random data which looks like a
3189          * possibly credible NAND flash to appear. If the two results do
3190          * not match, ignore the device completely.
3191          */
3192
3193         chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
3194
3195         /* Read entire ID string */
3196         for (i = 0; i < 8; i++)
3197                 id_data[i] = chip->read_byte(mtd);
3198
3199         if (id_data[0] != *maf_id || id_data[1] != *dev_id) {
3200                 pr_info("%s: second ID read did not match "
3201                         "%02x,%02x against %02x,%02x\n", __func__,
3202                         *maf_id, *dev_id, id_data[0], id_data[1]);
3203                 return ERR_PTR(-ENODEV);
3204         }
3205
3206         if (!type)
3207                 type = nand_flash_ids;
3208
3209         for (; type->name != NULL; type++)
3210                 if (*dev_id == type->id)
3211                         break;
3212
3213         chip->onfi_version = 0;
3214         if (!type->name || !type->pagesize) {
3215                 /* Check is chip is ONFI compliant */
3216                 if (nand_flash_detect_onfi(mtd, chip, &busw))
3217                         goto ident_done;
3218         }
3219
3220         if (!type->name)
3221                 return ERR_PTR(-ENODEV);
3222
3223         if (!mtd->name)
3224                 mtd->name = type->name;
3225
3226         chip->chipsize = (uint64_t)type->chipsize << 20;
3227
3228         if (!type->pagesize && chip->init_size) {
3229                 /* Set the pagesize, oobsize, erasesize by the driver */
3230                 busw = chip->init_size(mtd, chip, id_data);
3231         } else if (!type->pagesize) {
3232                 /* Decode parameters from extended ID */
3233                 nand_decode_ext_id(mtd, chip, id_data, &busw);
3234         } else {
3235                 nand_decode_id(mtd, chip, type, id_data, &busw);
3236         }
3237         /* Get chip options */
3238         chip->options |= type->options;
3239
3240         /*
3241          * Check if chip is not a Samsung device. Do not clear the
3242          * options for chips which do not have an extended id.
3243          */
3244         if (*maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
3245                 chip->options &= ~NAND_SAMSUNG_LP_OPTIONS;
3246 ident_done:
3247
3248         /* Try to identify manufacturer */
3249         for (maf_idx = 0; nand_manuf_ids[maf_idx].id != 0x0; maf_idx++) {
3250                 if (nand_manuf_ids[maf_idx].id == *maf_id)
3251                         break;
3252         }
3253
3254         if (chip->options & NAND_BUSWIDTH_AUTO) {
3255                 WARN_ON(chip->options & NAND_BUSWIDTH_16);
3256                 chip->options |= busw;
3257                 nand_set_defaults(chip, busw);
3258         } else if (busw != (chip->options & NAND_BUSWIDTH_16)) {
3259                 /*
3260                  * Check, if buswidth is correct. Hardware drivers should set
3261                  * chip correct!
3262                  */
3263                 pr_info("NAND device: Manufacturer ID:"
3264                         " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id,
3265                         *dev_id, nand_manuf_ids[maf_idx].name, mtd->name);
3266                 pr_warn("NAND bus width %d instead %d bit\n",
3267                            (chip->options & NAND_BUSWIDTH_16) ? 16 : 8,
3268                            busw ? 16 : 8);
3269                 return ERR_PTR(-EINVAL);
3270         }
3271
3272         nand_decode_bbm_options(mtd, chip, id_data);
3273
3274         /* Calculate the address shift from the page size */
3275         chip->page_shift = ffs(mtd->writesize) - 1;
3276         /* Convert chipsize to number of pages per chip -1 */
3277         chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
3278
3279         chip->bbt_erase_shift = chip->phys_erase_shift =
3280                 ffs(mtd->erasesize) - 1;
3281         if (chip->chipsize & 0xffffffff)
3282                 chip->chip_shift = ffs((unsigned)chip->chipsize) - 1;
3283         else {
3284                 chip->chip_shift = ffs((unsigned)(chip->chipsize >> 32));
3285                 chip->chip_shift += 32 - 1;
3286         }
3287
3288         chip->badblockbits = 8;
3289
3290         /* Check for AND chips with 4 page planes */
3291         if (chip->options & NAND_4PAGE_ARRAY)
3292                 chip->erase_cmd = multi_erase_cmd;
3293         else
3294                 chip->erase_cmd = single_erase_cmd;
3295
3296         /* Do not replace user supplied command function! */
3297         if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
3298                 chip->cmdfunc = nand_command_lp;
3299
3300         pr_info("NAND device: Manufacturer ID: 0x%02x, Chip ID: 0x%02x (%s %s),"
3301                 " %dMiB, page size: %d, OOB size: %d\n",
3302                 *maf_id, *dev_id, nand_manuf_ids[maf_idx].name,
3303                 chip->onfi_version ? chip->onfi_params.model : type->name,
3304                 (int)(chip->chipsize >> 20), mtd->writesize, mtd->oobsize);
3305
3306         return type;
3307 }
3308
3309 /**
3310  * nand_scan_ident - [NAND Interface] Scan for the NAND device
3311  * @mtd: MTD device structure
3312  * @maxchips: number of chips to scan for
3313  * @table: alternative NAND ID table
3314  *
3315  * This is the first phase of the normal nand_scan() function. It reads the
3316  * flash ID and sets up MTD fields accordingly.
3317  *
3318  * The mtd->owner field must be set to the module of the caller.
3319  */
3320 int nand_scan_ident(struct mtd_info *mtd, int maxchips,
3321                     struct nand_flash_dev *table)
3322 {
3323         int i, busw, nand_maf_id, nand_dev_id;
3324         struct nand_chip *chip = mtd->priv;
3325         struct nand_flash_dev *type;
3326
3327         /* Get buswidth to select the correct functions */
3328         busw = chip->options & NAND_BUSWIDTH_16;
3329         /* Set the default functions */
3330         nand_set_defaults(chip, busw);
3331
3332         /* Read the flash type */
3333         type = nand_get_flash_type(mtd, chip, busw,
3334                                 &nand_maf_id, &nand_dev_id, table);
3335
3336         if (IS_ERR(type)) {
3337                 if (!(chip->options & NAND_SCAN_SILENT_NODEV))
3338                         pr_warn("No NAND device found\n");
3339                 chip->select_chip(mtd, -1);
3340                 return PTR_ERR(type);
3341         }
3342
3343         chip->select_chip(mtd, -1);
3344
3345         /* Check for a chip array */
3346         for (i = 1; i < maxchips; i++) {
3347                 chip->select_chip(mtd, i);
3348                 /* See comment in nand_get_flash_type for reset */
3349                 chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
3350                 /* Send the command for reading device ID */
3351                 chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
3352                 /* Read manufacturer and device IDs */
3353                 if (nand_maf_id != chip->read_byte(mtd) ||
3354                     nand_dev_id != chip->read_byte(mtd)) {
3355                         chip->select_chip(mtd, -1);
3356                         break;
3357                 }
3358                 chip->select_chip(mtd, -1);
3359         }
3360         if (i > 1)
3361                 pr_info("%d NAND chips detected\n", i);
3362
3363         /* Store the number of chips and calc total size for mtd */
3364         chip->numchips = i;
3365         mtd->size = i * chip->chipsize;
3366
3367         return 0;
3368 }
3369 EXPORT_SYMBOL(nand_scan_ident);
3370
3371
3372 /**
3373  * nand_scan_tail - [NAND Interface] Scan for the NAND device
3374  * @mtd: MTD device structure
3375  *
3376  * This is the second phase of the normal nand_scan() function. It fills out
3377  * all the uninitialized function pointers with the defaults and scans for a
3378  * bad block table if appropriate.
3379  */
3380 int nand_scan_tail(struct mtd_info *mtd)
3381 {
3382         int i;
3383         struct nand_chip *chip = mtd->priv;
3384
3385         /* New bad blocks should be marked in OOB, flash-based BBT, or both */
3386         BUG_ON((chip->bbt_options & NAND_BBT_NO_OOB_BBM) &&
3387                         !(chip->bbt_options & NAND_BBT_USE_FLASH));
3388
3389         if (!(chip->options & NAND_OWN_BUFFERS))
3390                 chip->buffers = kmalloc(sizeof(*chip->buffers), GFP_KERNEL);
3391         if (!chip->buffers)
3392                 return -ENOMEM;
3393
3394         /* Set the internal oob buffer location, just after the page data */
3395         chip->oob_poi = chip->buffers->databuf + mtd->writesize;
3396
3397         /*
3398          * If no default placement scheme is given, select an appropriate one.
3399          */
3400         if (!chip->ecc.layout && (chip->ecc.mode != NAND_ECC_SOFT_BCH)) {
3401                 switch (mtd->oobsize) {
3402                 case 8:
3403                         chip->ecc.layout = &nand_oob_8;
3404                         break;
3405                 case 16:
3406                         chip->ecc.layout = &nand_oob_16;
3407                         break;
3408                 case 64:
3409                         chip->ecc.layout = &nand_oob_64;
3410                         break;
3411                 case 128:
3412                         chip->ecc.layout = &nand_oob_128;
3413                         break;
3414                 default:
3415                         pr_warn("No oob scheme defined for oobsize %d\n",
3416                                    mtd->oobsize);
3417                         BUG();
3418                 }
3419         }
3420
3421         if (!chip->write_page)
3422                 chip->write_page = nand_write_page;
3423
3424         /* set for ONFI nand */
3425         if (!chip->onfi_set_features)
3426                 chip->onfi_set_features = nand_onfi_set_features;
3427         if (!chip->onfi_get_features)
3428                 chip->onfi_get_features = nand_onfi_get_features;
3429
3430         /*
3431          * Check ECC mode, default to software if 3byte/512byte hardware ECC is
3432          * selected and we have 256 byte pagesize fallback to software ECC
3433          */
3434
3435         switch (chip->ecc.mode) {
3436         case NAND_ECC_HW_OOB_FIRST:
3437                 /* Similar to NAND_ECC_HW, but a separate read_page handle */
3438                 if (!chip->ecc.calculate || !chip->ecc.correct ||
3439                      !chip->ecc.hwctl) {
3440                         pr_warn("No ECC functions supplied; "
3441                                    "hardware ECC not possible\n");
3442                         BUG();
3443                 }
3444                 if (!chip->ecc.read_page)
3445                         chip->ecc.read_page = nand_read_page_hwecc_oob_first;
3446
3447         case NAND_ECC_HW:
3448                 /* Use standard hwecc read page function? */
3449                 if (!chip->ecc.read_page)
3450                         chip->ecc.read_page = nand_read_page_hwecc;
3451                 if (!chip->ecc.write_page)
3452                         chip->ecc.write_page = nand_write_page_hwecc;
3453                 if (!chip->ecc.read_page_raw)
3454                         chip->ecc.read_page_raw = nand_read_page_raw;
3455                 if (!chip->ecc.write_page_raw)
3456                         chip->ecc.write_page_raw = nand_write_page_raw;
3457                 if (!chip->ecc.read_oob)
3458                         chip->ecc.read_oob = nand_read_oob_std;
3459                 if (!chip->ecc.write_oob)
3460                         chip->ecc.write_oob = nand_write_oob_std;
3461
3462         case NAND_ECC_HW_SYNDROME:
3463                 if ((!chip->ecc.calculate || !chip->ecc.correct ||
3464                      !chip->ecc.hwctl) &&
3465                     (!chip->ecc.read_page ||
3466                      chip->ecc.read_page == nand_read_page_hwecc ||
3467                      !chip->ecc.write_page ||
3468                      chip->ecc.write_page == nand_write_page_hwecc)) {
3469                         pr_warn("No ECC functions supplied; "
3470                                    "hardware ECC not possible\n");
3471                         BUG();
3472                 }
3473                 /* Use standard syndrome read/write page function? */
3474                 if (!chip->ecc.read_page)
3475                         chip->ecc.read_page = nand_read_page_syndrome;
3476                 if (!chip->ecc.write_page)
3477                         chip->ecc.write_page = nand_write_page_syndrome;
3478                 if (!chip->ecc.read_page_raw)
3479                         chip->ecc.read_page_raw = nand_read_page_raw_syndrome;
3480                 if (!chip->ecc.write_page_raw)
3481                         chip->ecc.write_page_raw = nand_write_page_raw_syndrome;
3482                 if (!chip->ecc.read_oob)
3483                         chip->ecc.read_oob = nand_read_oob_syndrome;
3484                 if (!chip->ecc.write_oob)
3485                         chip->ecc.write_oob = nand_write_oob_syndrome;
3486
3487                 if (mtd->writesize >= chip->ecc.size) {
3488                         if (!chip->ecc.strength) {
3489                                 pr_warn("Driver must set ecc.strength when using hardware ECC\n");
3490                                 BUG();
3491                         }
3492                         break;
3493                 }
3494                 pr_warn("%d byte HW ECC not possible on "
3495                            "%d byte page size, fallback to SW ECC\n",
3496                            chip->ecc.size, mtd->writesize);
3497                 chip->ecc.mode = NAND_ECC_SOFT;
3498
3499         case NAND_ECC_SOFT:
3500                 chip->ecc.calculate = nand_calculate_ecc;
3501                 chip->ecc.correct = nand_correct_data;
3502                 chip->ecc.read_page = nand_read_page_swecc;
3503                 chip->ecc.read_subpage = nand_read_subpage;
3504                 chip->ecc.write_page = nand_write_page_swecc;
3505                 chip->ecc.read_page_raw = nand_read_page_raw;
3506                 chip->ecc.write_page_raw = nand_write_page_raw;
3507                 chip->ecc.read_oob = nand_read_oob_std;
3508                 chip->ecc.write_oob = nand_write_oob_std;
3509                 if (!chip->ecc.size)
3510                         chip->ecc.size = 256;
3511                 chip->ecc.bytes = 3;
3512                 chip->ecc.strength = 1;
3513                 break;
3514
3515         case NAND_ECC_SOFT_BCH:
3516                 if (!mtd_nand_has_bch()) {
3517                         pr_warn("CONFIG_MTD_ECC_BCH not enabled\n");
3518                         BUG();
3519                 }
3520                 chip->ecc.calculate = nand_bch_calculate_ecc;
3521                 chip->ecc.correct = nand_bch_correct_data;
3522                 chip->ecc.read_page = nand_read_page_swecc;
3523                 chip->ecc.read_subpage = nand_read_subpage;
3524                 chip->ecc.write_page = nand_write_page_swecc;
3525                 chip->ecc.read_page_raw = nand_read_page_raw;
3526                 chip->ecc.write_page_raw = nand_write_page_raw;
3527                 chip->ecc.read_oob = nand_read_oob_std;
3528                 chip->ecc.write_oob = nand_write_oob_std;
3529                 /*
3530                  * Board driver should supply ecc.size and ecc.bytes values to
3531                  * select how many bits are correctable; see nand_bch_init()
3532                  * for details. Otherwise, default to 4 bits for large page
3533                  * devices.
3534                  */
3535                 if (!chip->ecc.size && (mtd->oobsize >= 64)) {
3536                         chip->ecc.size = 512;
3537                         chip->ecc.bytes = 7;
3538                 }
3539                 chip->ecc.priv = nand_bch_init(mtd,
3540                                                chip->ecc.size,
3541                                                chip->ecc.bytes,
3542                                                &chip->ecc.layout);
3543                 if (!chip->ecc.priv) {
3544                         pr_warn("BCH ECC initialization failed!\n");
3545                         BUG();
3546                 }
3547                 chip->ecc.strength =
3548                         chip->ecc.bytes * 8 / fls(8 * chip->ecc.size);
3549                 break;
3550
3551         case NAND_ECC_NONE:
3552                 pr_warn("NAND_ECC_NONE selected by board driver. "
3553                            "This is not recommended!\n");
3554                 chip->ecc.read_page = nand_read_page_raw;
3555                 chip->ecc.write_page = nand_write_page_raw;
3556                 chip->ecc.read_oob = nand_read_oob_std;
3557                 chip->ecc.read_page_raw = nand_read_page_raw;
3558                 chip->ecc.write_page_raw = nand_write_page_raw;
3559                 chip->ecc.write_oob = nand_write_oob_std;
3560                 chip->ecc.size = mtd->writesize;
3561                 chip->ecc.bytes = 0;
3562                 chip->ecc.strength = 0;
3563                 break;
3564
3565         default:
3566                 pr_warn("Invalid NAND_ECC_MODE %d\n", chip->ecc.mode);
3567                 BUG();
3568         }
3569
3570         /* For many systems, the standard OOB write also works for raw */
3571         if (!chip->ecc.read_oob_raw)
3572                 chip->ecc.read_oob_raw = chip->ecc.read_oob;
3573         if (!chip->ecc.write_oob_raw)
3574                 chip->ecc.write_oob_raw = chip->ecc.write_oob;
3575
3576         /*
3577          * The number of bytes available for a client to place data into
3578          * the out of band area.
3579          */
3580         chip->ecc.layout->oobavail = 0;
3581         for (i = 0; chip->ecc.layout->oobfree[i].length
3582                         && i < ARRAY_SIZE(chip->ecc.layout->oobfree); i++)
3583                 chip->ecc.layout->oobavail +=
3584                         chip->ecc.layout->oobfree[i].length;
3585         mtd->oobavail = chip->ecc.layout->oobavail;
3586
3587         /*
3588          * Set the number of read / write steps for one page depending on ECC
3589          * mode.
3590          */
3591         chip->ecc.steps = mtd->writesize / chip->ecc.size;
3592         if (chip->ecc.steps * chip->ecc.size != mtd->writesize) {
3593                 pr_warn("Invalid ECC parameters\n");
3594                 BUG();
3595         }
3596         chip->ecc.total = chip->ecc.steps * chip->ecc.bytes;
3597
3598         /* Allow subpage writes up to ecc.steps. Not possible for MLC flash */
3599         if (!(chip->options & NAND_NO_SUBPAGE_WRITE) &&
3600             !(chip->cellinfo & NAND_CI_CELLTYPE_MSK)) {
3601                 switch (chip->ecc.steps) {
3602                 case 2:
3603                         mtd->subpage_sft = 1;
3604                         break;
3605                 case 4:
3606                 case 8:
3607                 case 16:
3608                         mtd->subpage_sft = 2;
3609                         break;
3610                 }
3611         }
3612         chip->subpagesize = mtd->writesize >> mtd->subpage_sft;
3613
3614         /* Initialize state */
3615         chip->state = FL_READY;
3616
3617         /* Invalidate the pagebuffer reference */
3618         chip->pagebuf = -1;
3619
3620         /* Large page NAND with SOFT_ECC should support subpage reads */
3621         if ((chip->ecc.mode == NAND_ECC_SOFT) && (chip->page_shift > 9))
3622                 chip->options |= NAND_SUBPAGE_READ;
3623
3624         /* Fill in remaining MTD driver data */
3625         mtd->type = MTD_NANDFLASH;
3626         mtd->flags = (chip->options & NAND_ROM) ? MTD_CAP_ROM :
3627                                                 MTD_CAP_NANDFLASH;
3628         mtd->_erase = nand_erase;
3629         mtd->_point = NULL;
3630         mtd->_unpoint = NULL;
3631         mtd->_read = nand_read;
3632         mtd->_write = nand_write;
3633         mtd->_panic_write = panic_nand_write;
3634         mtd->_read_oob = nand_read_oob;
3635         mtd->_write_oob = nand_write_oob;
3636         mtd->_sync = nand_sync;
3637         mtd->_lock = NULL;
3638         mtd->_unlock = NULL;
3639         mtd->_suspend = nand_suspend;
3640         mtd->_resume = nand_resume;
3641         mtd->_block_isbad = nand_block_isbad;
3642         mtd->_block_markbad = nand_block_markbad;
3643         mtd->writebufsize = mtd->writesize;
3644
3645         /* propagate ecc info to mtd_info */
3646         mtd->ecclayout = chip->ecc.layout;
3647         mtd->ecc_strength = chip->ecc.strength;
3648         /*
3649          * Initialize bitflip_threshold to its default prior scan_bbt() call.
3650          * scan_bbt() might invoke mtd_read(), thus bitflip_threshold must be
3651          * properly set.
3652          */
3653         if (!mtd->bitflip_threshold)
3654                 mtd->bitflip_threshold = mtd->ecc_strength;
3655
3656         /* Check, if we should skip the bad block table scan */
3657         if (chip->options & NAND_SKIP_BBTSCAN)
3658                 return 0;
3659
3660         /* Build bad block table */
3661         return chip->scan_bbt(mtd);
3662 }
3663 EXPORT_SYMBOL(nand_scan_tail);
3664
3665 /*
3666  * is_module_text_address() isn't exported, and it's mostly a pointless
3667  * test if this is a module _anyway_ -- they'd have to try _really_ hard
3668  * to call us from in-kernel code if the core NAND support is modular.
3669  */
3670 #ifdef MODULE
3671 #define caller_is_module() (1)
3672 #else
3673 #define caller_is_module() \
3674         is_module_text_address((unsigned long)__builtin_return_address(0))
3675 #endif
3676
3677 /**
3678  * nand_scan - [NAND Interface] Scan for the NAND device
3679  * @mtd: MTD device structure
3680  * @maxchips: number of chips to scan for
3681  *
3682  * This fills out all the uninitialized function pointers with the defaults.
3683  * The flash ID is read and the mtd/chip structures are filled with the
3684  * appropriate values. The mtd->owner field must be set to the module of the
3685  * caller.
3686  */
3687 int nand_scan(struct mtd_info *mtd, int maxchips)
3688 {
3689         int ret;
3690
3691         /* Many callers got this wrong, so check for it for a while... */
3692         if (!mtd->owner && caller_is_module()) {
3693                 pr_crit("%s called with NULL mtd->owner!\n", __func__);
3694                 BUG();
3695         }
3696
3697         ret = nand_scan_ident(mtd, maxchips, NULL);
3698         if (!ret)
3699                 ret = nand_scan_tail(mtd);
3700         return ret;
3701 }
3702 EXPORT_SYMBOL(nand_scan);
3703
3704 /**
3705  * nand_release - [NAND Interface] Free resources held by the NAND device
3706  * @mtd: MTD device structure
3707  */
3708 void nand_release(struct mtd_info *mtd)
3709 {
3710         struct nand_chip *chip = mtd->priv;
3711
3712         if (chip->ecc.mode == NAND_ECC_SOFT_BCH)
3713                 nand_bch_free((struct nand_bch_control *)chip->ecc.priv);
3714
3715         mtd_device_unregister(mtd);
3716
3717         /* Free bad block table memory */
3718         kfree(chip->bbt);
3719         if (!(chip->options & NAND_OWN_BUFFERS))
3720                 kfree(chip->buffers);
3721
3722         /* Free bad block descriptor memory */
3723         if (chip->badblock_pattern && chip->badblock_pattern->options
3724                         & NAND_BBT_DYNAMICSTRUCT)
3725                 kfree(chip->badblock_pattern);
3726 }
3727 EXPORT_SYMBOL_GPL(nand_release);
3728
3729 static int __init nand_base_init(void)
3730 {
3731         led_trigger_register_simple("nand-disk", &nand_led_trigger);
3732         return 0;
3733 }
3734
3735 static void __exit nand_base_exit(void)
3736 {
3737         led_trigger_unregister_simple(nand_led_trigger);
3738 }
3739
3740 module_init(nand_base_init);
3741 module_exit(nand_base_exit);
3742
3743 MODULE_LICENSE("GPL");
3744 MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>");
3745 MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>");
3746 MODULE_DESCRIPTION("Generic NAND flash driver code");