3 * Bad block table support for the NAND driver
5 * Copyright © 2004 Thomas Gleixner (tglx@linutronix.de)
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
13 * When nand_scan_bbt is called, then it tries to find the bad block table
14 * depending on the options in the BBT descriptor(s). If no flash based BBT
15 * (NAND_BBT_USE_FLASH) is specified then the device is scanned for factory
16 * marked good / bad blocks. This information is used to create a memory BBT.
17 * Once a new bad block is discovered then the "factory" information is updated
19 * If a flash based BBT is specified then the function first tries to find the
20 * BBT on flash. If a BBT is found then the contents are read and the memory
21 * based BBT is created. If a mirrored BBT is selected then the mirror is
22 * searched too and the versions are compared. If the mirror has a greater
23 * version number, then the mirror BBT is used to build the memory based BBT.
24 * If the tables are not versioned, then we "or" the bad block information.
25 * If one of the BBTs is out of date or does not exist it is (re)created.
26 * If no BBT exists at all then the device is scanned for factory marked
27 * good / bad blocks and the bad block tables are created.
29 * For manufacturer created BBTs like the one found on M-SYS DOC devices
30 * the BBT is searched and read but never created
32 * The auto generated bad block table is located in the last good blocks
33 * of the device. The table is mirrored, so it can be updated eventually.
34 * The table is marked in the OOB area with an ident pattern and a version
35 * number which indicates which of both tables is more up to date. If the NAND
36 * controller needs the complete OOB area for the ECC information then the
37 * option NAND_BBT_NO_OOB should be used (along with NAND_BBT_USE_FLASH, of
38 * course): it moves the ident pattern and the version byte into the data area
39 * and the OOB area will remain untouched.
41 * The table uses 2 bits per block
43 * 00b: block is factory marked bad
44 * 01b, 10b: block is marked bad due to wear
46 * The memory bad block table uses the following scheme:
48 * 01b: block is marked bad due to wear
49 * 10b: block is reserved (to protect the bbt area)
50 * 11b: block is factory marked bad
52 * Multichip devices like DOC store the bad block info per floor.
54 * Following assumptions are made:
55 * - bbts start at a page boundary, if autolocated on a block boundary
56 * - the space necessary for a bbt in FLASH does not exceed a block boundary
63 #include <dm/devres.h>
64 #include <linux/bug.h>
65 #include <linux/compat.h>
66 #include <linux/mtd/mtd.h>
67 #include <linux/mtd/bbm.h>
68 #include <linux/mtd/rawnand.h>
69 #include <linux/bitops.h>
70 #include <linux/string.h>
72 #define BBT_BLOCK_GOOD 0x00
73 #define BBT_BLOCK_WORN 0x01
74 #define BBT_BLOCK_RESERVED 0x02
75 #define BBT_BLOCK_FACTORY_BAD 0x03
77 #define BBT_ENTRY_MASK 0x03
78 #define BBT_ENTRY_SHIFT 2
80 static int nand_update_bbt(struct mtd_info
*mtd
, loff_t offs
);
82 static inline uint8_t bbt_get_entry(struct nand_chip
*chip
, int block
)
84 uint8_t entry
= chip
->bbt
[block
>> BBT_ENTRY_SHIFT
];
85 entry
>>= (block
& BBT_ENTRY_MASK
) * 2;
86 return entry
& BBT_ENTRY_MASK
;
89 static inline void bbt_mark_entry(struct nand_chip
*chip
, int block
,
92 uint8_t msk
= (mark
& BBT_ENTRY_MASK
) << ((block
& BBT_ENTRY_MASK
) * 2);
93 chip
->bbt
[block
>> BBT_ENTRY_SHIFT
] |= msk
;
96 static int check_pattern_no_oob(uint8_t *buf
, struct nand_bbt_descr
*td
)
98 if (memcmp(buf
, td
->pattern
, td
->len
))
104 * check_pattern - [GENERIC] check if a pattern is in the buffer
105 * @buf: the buffer to search
106 * @len: the length of buffer to search
107 * @paglen: the pagelength
108 * @td: search pattern descriptor
110 * Check for a pattern at the given place. Used to search bad block tables and
111 * good / bad block identifiers.
113 static int check_pattern(uint8_t *buf
, int len
, int paglen
, struct nand_bbt_descr
*td
)
115 if (td
->options
& NAND_BBT_NO_OOB
)
116 return check_pattern_no_oob(buf
, td
);
118 /* Compare the pattern */
119 if (memcmp(buf
+ paglen
+ td
->offs
, td
->pattern
, td
->len
))
126 * check_short_pattern - [GENERIC] check if a pattern is in the buffer
127 * @buf: the buffer to search
128 * @td: search pattern descriptor
130 * Check for a pattern at the given place. Used to search bad block tables and
131 * good / bad block identifiers. Same as check_pattern, but no optional empty
134 static int check_short_pattern(uint8_t *buf
, struct nand_bbt_descr
*td
)
136 /* Compare the pattern */
137 if (memcmp(buf
+ td
->offs
, td
->pattern
, td
->len
))
143 * add_marker_len - compute the length of the marker in data area
144 * @td: BBT descriptor used for computation
146 * The length will be 0 if the marker is located in OOB area.
148 static u32
add_marker_len(struct nand_bbt_descr
*td
)
152 if (!(td
->options
& NAND_BBT_NO_OOB
))
156 if (td
->options
& NAND_BBT_VERSION
)
162 * read_bbt - [GENERIC] Read the bad block table starting from page
163 * @mtd: MTD device structure
164 * @buf: temporary buffer
165 * @page: the starting page
166 * @num: the number of bbt descriptors to read
167 * @td: the bbt describtion table
168 * @offs: block number offset in the table
170 * Read the bad block table starting from page.
172 static int read_bbt(struct mtd_info
*mtd
, uint8_t *buf
, int page
, int num
,
173 struct nand_bbt_descr
*td
, int offs
)
175 int res
, ret
= 0, i
, j
, act
= 0;
176 struct nand_chip
*this = mtd_to_nand(mtd
);
177 size_t retlen
, len
, totlen
;
179 int bits
= td
->options
& NAND_BBT_NRBITS_MSK
;
180 uint8_t msk
= (uint8_t)((1 << bits
) - 1);
182 int reserved_block_code
= td
->reserved_block_code
;
184 totlen
= (num
* bits
) >> 3;
185 marker_len
= add_marker_len(td
);
186 from
= ((loff_t
)page
) << this->page_shift
;
189 len
= min(totlen
, (size_t)(1 << this->bbt_erase_shift
));
192 * In case the BBT marker is not in the OOB area it
193 * will be just in the first page.
199 res
= mtd_read(mtd
, from
, len
, &retlen
, buf
);
201 if (mtd_is_eccerr(res
)) {
202 pr_info("nand_bbt: ECC error in BBT at 0x%012llx\n",
203 from
& ~mtd
->writesize
);
205 } else if (mtd_is_bitflip(res
)) {
206 pr_info("nand_bbt: corrected error in BBT at 0x%012llx\n",
207 from
& ~mtd
->writesize
);
210 pr_info("nand_bbt: error reading BBT\n");
216 for (i
= 0; i
< len
; i
++) {
217 uint8_t dat
= buf
[i
];
218 for (j
= 0; j
< 8; j
+= bits
, act
++) {
219 uint8_t tmp
= (dat
>> j
) & msk
;
222 if (reserved_block_code
&& (tmp
== reserved_block_code
)) {
223 pr_info("nand_read_bbt: reserved block at 0x%012llx\n",
224 (loff_t
)(offs
+ act
) <<
225 this->bbt_erase_shift
);
226 bbt_mark_entry(this, offs
+ act
,
228 mtd
->ecc_stats
.bbtblocks
++;
232 * Leave it for now, if it's matured we can
233 * move this message to pr_debug.
235 pr_info("nand_read_bbt: bad block at 0x%012llx\n",
236 (loff_t
)(offs
+ act
) <<
237 this->bbt_erase_shift
);
238 /* Factory marked bad or worn out? */
240 bbt_mark_entry(this, offs
+ act
,
241 BBT_BLOCK_FACTORY_BAD
);
243 bbt_mark_entry(this, offs
+ act
,
245 mtd
->ecc_stats
.badblocks
++;
255 * read_abs_bbt - [GENERIC] Read the bad block table starting at a given page
256 * @mtd: MTD device structure
257 * @buf: temporary buffer
258 * @td: descriptor for the bad block table
259 * @chip: read the table for a specific chip, -1 read all chips; applies only if
260 * NAND_BBT_PERCHIP option is set
262 * Read the bad block table for all chips starting at a given page. We assume
263 * that the bbt bits are in consecutive order.
265 static int read_abs_bbt(struct mtd_info
*mtd
, uint8_t *buf
, struct nand_bbt_descr
*td
, int chip
)
267 struct nand_chip
*this = mtd_to_nand(mtd
);
270 if (td
->options
& NAND_BBT_PERCHIP
) {
272 for (i
= 0; i
< this->numchips
; i
++) {
273 if (chip
== -1 || chip
== i
)
274 res
= read_bbt(mtd
, buf
, td
->pages
[i
],
275 this->chipsize
>> this->bbt_erase_shift
,
279 offs
+= this->chipsize
>> this->bbt_erase_shift
;
282 res
= read_bbt(mtd
, buf
, td
->pages
[0],
283 mtd
->size
>> this->bbt_erase_shift
, td
, 0);
290 /* BBT marker is in the first page, no OOB */
291 static int scan_read_data(struct mtd_info
*mtd
, uint8_t *buf
, loff_t offs
,
292 struct nand_bbt_descr
*td
)
298 if (td
->options
& NAND_BBT_VERSION
)
301 return mtd_read(mtd
, offs
, len
, &retlen
, buf
);
305 * scan_read_oob - [GENERIC] Scan data+OOB region to buffer
306 * @mtd: MTD device structure
307 * @buf: temporary buffer
308 * @offs: offset at which to scan
309 * @len: length of data region to read
311 * Scan read data from data+OOB. May traverse multiple pages, interleaving
312 * page,OOB,page,OOB,... in buf. Completes transfer and returns the "strongest"
313 * ECC condition (error or bitflip). May quit on the first (non-ECC) error.
315 static int scan_read_oob(struct mtd_info
*mtd
, uint8_t *buf
, loff_t offs
,
318 struct mtd_oob_ops ops
;
321 ops
.mode
= MTD_OPS_PLACE_OOB
;
323 ops
.ooblen
= mtd
->oobsize
;
327 ops
.len
= min(len
, (size_t)mtd
->writesize
);
328 ops
.oobbuf
= buf
+ ops
.len
;
330 res
= mtd_read_oob(mtd
, offs
, &ops
);
332 if (!mtd_is_bitflip_or_eccerr(res
))
334 else if (mtd_is_eccerr(res
) || !ret
)
338 buf
+= mtd
->oobsize
+ mtd
->writesize
;
339 len
-= mtd
->writesize
;
340 offs
+= mtd
->writesize
;
345 static int scan_read(struct mtd_info
*mtd
, uint8_t *buf
, loff_t offs
,
346 size_t len
, struct nand_bbt_descr
*td
)
348 if (td
->options
& NAND_BBT_NO_OOB
)
349 return scan_read_data(mtd
, buf
, offs
, td
);
351 return scan_read_oob(mtd
, buf
, offs
, len
);
354 /* Scan write data with oob to flash */
355 static int scan_write_bbt(struct mtd_info
*mtd
, loff_t offs
, size_t len
,
356 uint8_t *buf
, uint8_t *oob
)
358 struct mtd_oob_ops ops
;
360 ops
.mode
= MTD_OPS_PLACE_OOB
;
362 ops
.ooblen
= mtd
->oobsize
;
367 return mtd_write_oob(mtd
, offs
, &ops
);
370 static u32
bbt_get_ver_offs(struct mtd_info
*mtd
, struct nand_bbt_descr
*td
)
372 u32 ver_offs
= td
->veroffs
;
374 if (!(td
->options
& NAND_BBT_NO_OOB
))
375 ver_offs
+= mtd
->writesize
;
380 * read_abs_bbts - [GENERIC] Read the bad block table(s) for all chips starting at a given page
381 * @mtd: MTD device structure
382 * @buf: temporary buffer
383 * @td: descriptor for the bad block table
384 * @md: descriptor for the bad block table mirror
386 * Read the bad block table(s) for all chips starting at a given page. We
387 * assume that the bbt bits are in consecutive order.
389 static void read_abs_bbts(struct mtd_info
*mtd
, uint8_t *buf
,
390 struct nand_bbt_descr
*td
, struct nand_bbt_descr
*md
)
392 struct nand_chip
*this = mtd_to_nand(mtd
);
394 /* Read the primary version, if available */
395 if (td
->options
& NAND_BBT_VERSION
) {
396 scan_read(mtd
, buf
, (loff_t
)td
->pages
[0] << this->page_shift
,
398 td
->version
[0] = buf
[bbt_get_ver_offs(mtd
, td
)];
399 pr_info("Bad block table at page %d, version 0x%02X\n",
400 td
->pages
[0], td
->version
[0]);
403 /* Read the mirror version, if available */
404 if (md
&& (md
->options
& NAND_BBT_VERSION
)) {
405 scan_read(mtd
, buf
, (loff_t
)md
->pages
[0] << this->page_shift
,
407 md
->version
[0] = buf
[bbt_get_ver_offs(mtd
, md
)];
408 pr_info("Bad block table at page %d, version 0x%02X\n",
409 md
->pages
[0], md
->version
[0]);
413 /* Scan a given block partially */
414 static int scan_block_fast(struct mtd_info
*mtd
, struct nand_bbt_descr
*bd
,
415 loff_t offs
, uint8_t *buf
, int numpages
)
417 struct mtd_oob_ops ops
;
420 ops
.ooblen
= mtd
->oobsize
;
424 ops
.mode
= MTD_OPS_PLACE_OOB
;
426 for (j
= 0; j
< numpages
; j
++) {
428 * Read the full oob until read_oob is fixed to handle single
429 * byte reads for 16 bit buswidth.
431 ret
= mtd_read_oob(mtd
, offs
, &ops
);
432 /* Ignore ECC errors when checking for BBM */
433 if (ret
&& !mtd_is_bitflip_or_eccerr(ret
))
436 if (check_short_pattern(buf
, bd
))
439 offs
+= mtd
->writesize
;
445 * create_bbt - [GENERIC] Create a bad block table by scanning the device
446 * @mtd: MTD device structure
447 * @buf: temporary buffer
448 * @bd: descriptor for the good/bad block search pattern
449 * @chip: create the table for a specific chip, -1 read all chips; applies only
450 * if NAND_BBT_PERCHIP option is set
452 * Create a bad block table by scanning the device for the given good/bad block
455 static int create_bbt(struct mtd_info
*mtd
, uint8_t *buf
,
456 struct nand_bbt_descr
*bd
, int chip
)
458 struct nand_chip
*this = mtd_to_nand(mtd
);
459 int i
, numblocks
, numpages
;
463 pr_info("Scanning device for bad blocks\n");
465 if (bd
->options
& NAND_BBT_SCAN2NDPAGE
)
471 numblocks
= mtd
->size
>> this->bbt_erase_shift
;
475 if (chip
>= this->numchips
) {
476 pr_warn("create_bbt(): chipnr (%d) > available chips (%d)\n",
477 chip
+ 1, this->numchips
);
480 numblocks
= this->chipsize
>> this->bbt_erase_shift
;
481 startblock
= chip
* numblocks
;
482 numblocks
+= startblock
;
483 from
= (loff_t
)startblock
<< this->bbt_erase_shift
;
486 if (this->bbt_options
& NAND_BBT_SCANLASTPAGE
)
487 from
+= mtd
->erasesize
- (mtd
->writesize
* numpages
);
489 for (i
= startblock
; i
< numblocks
; i
++) {
492 BUG_ON(bd
->options
& NAND_BBT_NO_OOB
);
494 ret
= scan_block_fast(mtd
, bd
, from
, buf
, numpages
);
499 bbt_mark_entry(this, i
, BBT_BLOCK_FACTORY_BAD
);
500 pr_warn("Bad eraseblock %d at 0x%012llx\n",
501 i
, (unsigned long long)from
);
502 mtd
->ecc_stats
.badblocks
++;
505 from
+= (1 << this->bbt_erase_shift
);
511 * search_bbt - [GENERIC] scan the device for a specific bad block table
512 * @mtd: MTD device structure
513 * @buf: temporary buffer
514 * @td: descriptor for the bad block table
516 * Read the bad block table by searching for a given ident pattern. Search is
517 * preformed either from the beginning up or from the end of the device
518 * downwards. The search starts always at the start of a block. If the option
519 * NAND_BBT_PERCHIP is given, each chip is searched for a bbt, which contains
520 * the bad block information of this chip. This is necessary to provide support
521 * for certain DOC devices.
523 * The bbt ident pattern resides in the oob area of the first page in a block.
525 static int search_bbt(struct mtd_info
*mtd
, uint8_t *buf
, struct nand_bbt_descr
*td
)
527 struct nand_chip
*this = mtd_to_nand(mtd
);
529 int startblock
, block
, dir
;
530 int scanlen
= mtd
->writesize
+ mtd
->oobsize
;
532 int blocktopage
= this->bbt_erase_shift
- this->page_shift
;
534 /* Search direction top -> down? */
535 if (td
->options
& NAND_BBT_LASTBLOCK
) {
536 startblock
= (mtd
->size
>> this->bbt_erase_shift
) - 1;
543 /* Do we have a bbt per chip? */
544 if (td
->options
& NAND_BBT_PERCHIP
) {
545 chips
= this->numchips
;
546 bbtblocks
= this->chipsize
>> this->bbt_erase_shift
;
547 startblock
&= bbtblocks
- 1;
550 bbtblocks
= mtd
->size
>> this->bbt_erase_shift
;
553 for (i
= 0; i
< chips
; i
++) {
554 /* Reset version information */
557 /* Scan the maximum number of blocks */
558 for (block
= 0; block
< td
->maxblocks
; block
++) {
560 int actblock
= startblock
+ dir
* block
;
561 loff_t offs
= (loff_t
)actblock
<< this->bbt_erase_shift
;
563 /* Read first page */
564 scan_read(mtd
, buf
, offs
, mtd
->writesize
, td
);
565 if (!check_pattern(buf
, scanlen
, mtd
->writesize
, td
)) {
566 td
->pages
[i
] = actblock
<< blocktopage
;
567 if (td
->options
& NAND_BBT_VERSION
) {
568 offs
= bbt_get_ver_offs(mtd
, td
);
569 td
->version
[i
] = buf
[offs
];
574 startblock
+= this->chipsize
>> this->bbt_erase_shift
;
576 /* Check, if we found a bbt for each requested chip */
577 for (i
= 0; i
< chips
; i
++) {
578 if (td
->pages
[i
] == -1)
579 pr_warn("Bad block table not found for chip %d\n", i
);
581 pr_info("Bad block table found at page %d, version 0x%02X\n",
582 td
->pages
[i
], td
->version
[i
]);
588 * search_read_bbts - [GENERIC] scan the device for bad block table(s)
589 * @mtd: MTD device structure
590 * @buf: temporary buffer
591 * @td: descriptor for the bad block table
592 * @md: descriptor for the bad block table mirror
594 * Search and read the bad block table(s).
596 static void search_read_bbts(struct mtd_info
*mtd
, uint8_t *buf
,
597 struct nand_bbt_descr
*td
,
598 struct nand_bbt_descr
*md
)
600 /* Search the primary table */
601 search_bbt(mtd
, buf
, td
);
603 /* Search the mirror table */
605 search_bbt(mtd
, buf
, md
);
609 * write_bbt - [GENERIC] (Re)write the bad block table
610 * @mtd: MTD device structure
611 * @buf: temporary buffer
612 * @td: descriptor for the bad block table
613 * @md: descriptor for the bad block table mirror
614 * @chipsel: selector for a specific chip, -1 for all
616 * (Re)write the bad block table.
618 static int write_bbt(struct mtd_info
*mtd
, uint8_t *buf
,
619 struct nand_bbt_descr
*td
, struct nand_bbt_descr
*md
,
622 struct nand_chip
*this = mtd_to_nand(mtd
);
623 struct erase_info einfo
;
624 int i
, res
, chip
= 0;
625 int bits
, startblock
, dir
, page
, offs
, numblocks
, sft
, sftmsk
;
626 int nrchips
, pageoffs
, ooboffs
;
628 uint8_t rcode
= td
->reserved_block_code
;
629 size_t retlen
, len
= 0;
631 struct mtd_oob_ops ops
;
633 ops
.ooblen
= mtd
->oobsize
;
636 ops
.mode
= MTD_OPS_PLACE_OOB
;
640 /* Write bad block table per chip rather than per device? */
641 if (td
->options
& NAND_BBT_PERCHIP
) {
642 numblocks
= (int)(this->chipsize
>> this->bbt_erase_shift
);
643 /* Full device write or specific chip? */
645 nrchips
= this->numchips
;
647 nrchips
= chipsel
+ 1;
651 numblocks
= (int)(mtd
->size
>> this->bbt_erase_shift
);
655 /* Loop through the chips */
656 for (; chip
< nrchips
; chip
++) {
658 * There was already a version of the table, reuse the page
659 * This applies for absolute placement too, as we have the
660 * page nr. in td->pages.
662 if (td
->pages
[chip
] != -1) {
663 page
= td
->pages
[chip
];
668 * Automatic placement of the bad block table. Search direction
671 if (td
->options
& NAND_BBT_LASTBLOCK
) {
672 startblock
= numblocks
* (chip
+ 1) - 1;
675 startblock
= chip
* numblocks
;
679 for (i
= 0; i
< td
->maxblocks
; i
++) {
680 int block
= startblock
+ dir
* i
;
681 /* Check, if the block is bad */
682 switch (bbt_get_entry(this, block
)) {
684 case BBT_BLOCK_FACTORY_BAD
:
688 (this->bbt_erase_shift
- this->page_shift
);
689 /* Check, if the block is used by the mirror table */
690 if (!md
|| md
->pages
[chip
] != page
)
693 pr_err("No space left to write bad block table\n");
697 /* Set up shift count and masks for the flash table */
698 bits
= td
->options
& NAND_BBT_NRBITS_MSK
;
701 case 1: sft
= 3; sftmsk
= 0x07; msk
[0] = 0x00; msk
[1] = 0x01;
704 case 2: sft
= 2; sftmsk
= 0x06; msk
[0] = 0x00; msk
[1] = 0x01;
707 case 4: sft
= 1; sftmsk
= 0x04; msk
[0] = 0x00; msk
[1] = 0x0C;
710 case 8: sft
= 0; sftmsk
= 0x00; msk
[0] = 0x00; msk
[1] = 0x0F;
713 default: return -EINVAL
;
716 to
= ((loff_t
)page
) << this->page_shift
;
718 /* Must we save the block contents? */
719 if (td
->options
& NAND_BBT_SAVECONTENT
) {
720 /* Make it block aligned */
721 to
&= ~(((loff_t
)1 << this->bbt_erase_shift
) - 1);
722 len
= 1 << this->bbt_erase_shift
;
723 res
= mtd_read(mtd
, to
, len
, &retlen
, buf
);
726 pr_info("nand_bbt: error reading block for writing the bad block table\n");
729 pr_warn("nand_bbt: ECC error while reading block for writing bad block table\n");
732 ops
.ooblen
= (len
>> this->page_shift
) * mtd
->oobsize
;
733 ops
.oobbuf
= &buf
[len
];
734 res
= mtd_read_oob(mtd
, to
+ mtd
->writesize
, &ops
);
735 if (res
< 0 || ops
.oobretlen
!= ops
.ooblen
)
738 /* Calc the byte offset in the buffer */
739 pageoffs
= page
- (int)(to
>> this->page_shift
);
740 offs
= pageoffs
<< this->page_shift
;
741 /* Preset the bbt area with 0xff */
742 memset(&buf
[offs
], 0xff, (size_t)(numblocks
>> sft
));
743 ooboffs
= len
+ (pageoffs
* mtd
->oobsize
);
745 } else if (td
->options
& NAND_BBT_NO_OOB
) {
748 /* The version byte */
749 if (td
->options
& NAND_BBT_VERSION
)
752 len
= (size_t)(numblocks
>> sft
);
754 /* Make it page aligned! */
755 len
= ALIGN(len
, mtd
->writesize
);
756 /* Preset the buffer with 0xff */
757 memset(buf
, 0xff, len
);
758 /* Pattern is located at the begin of first page */
759 memcpy(buf
, td
->pattern
, td
->len
);
762 len
= (size_t)(numblocks
>> sft
);
763 /* Make it page aligned! */
764 len
= ALIGN(len
, mtd
->writesize
);
765 /* Preset the buffer with 0xff */
766 memset(buf
, 0xff, len
+
767 (len
>> this->page_shift
)* mtd
->oobsize
);
770 /* Pattern is located in oob area of first page */
771 memcpy(&buf
[ooboffs
+ td
->offs
], td
->pattern
, td
->len
);
774 if (td
->options
& NAND_BBT_VERSION
)
775 buf
[ooboffs
+ td
->veroffs
] = td
->version
[chip
];
777 /* Walk through the memory table */
778 for (i
= 0; i
< numblocks
; i
++) {
780 int sftcnt
= (i
<< (3 - sft
)) & sftmsk
;
781 dat
= bbt_get_entry(this, chip
* numblocks
+ i
);
782 /* Do not store the reserved bbt blocks! */
783 buf
[offs
+ (i
>> sft
)] &= ~(msk
[dat
] << sftcnt
);
786 memset(&einfo
, 0, sizeof(einfo
));
789 einfo
.len
= 1 << this->bbt_erase_shift
;
790 res
= nand_erase_nand(mtd
, &einfo
, 1);
794 res
= scan_write_bbt(mtd
, to
, len
, buf
,
795 td
->options
& NAND_BBT_NO_OOB
? NULL
:
800 pr_info("Bad block table written to 0x%012llx, version 0x%02X\n",
801 (unsigned long long)to
, td
->version
[chip
]);
803 /* Mark it as used */
804 td
->pages
[chip
] = page
;
809 pr_warn("nand_bbt: error while writing bad block table %d\n", res
);
814 * nand_memory_bbt - [GENERIC] create a memory based bad block table
815 * @mtd: MTD device structure
816 * @bd: descriptor for the good/bad block search pattern
818 * The function creates a memory based bbt by scanning the device for
819 * manufacturer / software marked good / bad blocks.
821 static inline int nand_memory_bbt(struct mtd_info
*mtd
, struct nand_bbt_descr
*bd
)
823 struct nand_chip
*this = mtd_to_nand(mtd
);
825 return create_bbt(mtd
, this->buffers
->databuf
, bd
, -1);
829 * check_create - [GENERIC] create and write bbt(s) if necessary
830 * @mtd: MTD device structure
831 * @buf: temporary buffer
832 * @bd: descriptor for the good/bad block search pattern
834 * The function checks the results of the previous call to read_bbt and creates
835 * / updates the bbt(s) if necessary. Creation is necessary if no bbt was found
836 * for the chip/device. Update is necessary if one of the tables is missing or
837 * the version nr. of one table is less than the other.
839 static int check_create(struct mtd_info
*mtd
, uint8_t *buf
, struct nand_bbt_descr
*bd
)
841 int i
, chips
, writeops
, create
, chipsel
, res
, res2
;
842 struct nand_chip
*this = mtd_to_nand(mtd
);
843 struct nand_bbt_descr
*td
= this->bbt_td
;
844 struct nand_bbt_descr
*md
= this->bbt_md
;
845 struct nand_bbt_descr
*rd
, *rd2
;
847 /* Do we have a bbt per chip? */
848 if (td
->options
& NAND_BBT_PERCHIP
)
849 chips
= this->numchips
;
853 for (i
= 0; i
< chips
; i
++) {
859 /* Per chip or per device? */
860 chipsel
= (td
->options
& NAND_BBT_PERCHIP
) ? i
: -1;
861 /* Mirrored table available? */
863 if (td
->pages
[i
] == -1 && md
->pages
[i
] == -1) {
866 } else if (td
->pages
[i
] == -1) {
869 } else if (md
->pages
[i
] == -1) {
872 } else if (td
->version
[i
] == md
->version
[i
]) {
874 if (!(td
->options
& NAND_BBT_VERSION
))
876 } else if (((int8_t)(td
->version
[i
] - md
->version
[i
])) > 0) {
884 if (td
->pages
[i
] == -1) {
893 /* Create the bad block table by scanning the device? */
894 if (!(td
->options
& NAND_BBT_CREATE
))
897 /* Create the table in memory by scanning the chip(s) */
898 if (!(this->bbt_options
& NAND_BBT_CREATE_EMPTY
))
899 create_bbt(mtd
, buf
, bd
, chipsel
);
906 /* Read back first? */
908 res
= read_abs_bbt(mtd
, buf
, rd
, chipsel
);
909 if (mtd_is_eccerr(res
)) {
910 /* Mark table as invalid */
917 /* If they weren't versioned, read both */
919 res2
= read_abs_bbt(mtd
, buf
, rd2
, chipsel
);
920 if (mtd_is_eccerr(res2
)) {
921 /* Mark table as invalid */
929 /* Scrub the flash table(s)? */
930 if (mtd_is_bitflip(res
) || mtd_is_bitflip(res2
))
933 /* Update version numbers before writing */
935 td
->version
[i
] = max(td
->version
[i
], md
->version
[i
]);
936 md
->version
[i
] = td
->version
[i
];
939 /* Write the bad block table to the device? */
940 if ((writeops
& 0x01) && (td
->options
& NAND_BBT_WRITE
)) {
941 res
= write_bbt(mtd
, buf
, td
, md
, chipsel
);
946 /* Write the mirror bad block table to the device? */
947 if ((writeops
& 0x02) && md
&& (md
->options
& NAND_BBT_WRITE
)) {
948 res
= write_bbt(mtd
, buf
, md
, td
, chipsel
);
957 * mark_bbt_regions - [GENERIC] mark the bad block table regions
958 * @mtd: MTD device structure
959 * @td: bad block table descriptor
961 * The bad block table regions are marked as "bad" to prevent accidental
962 * erasures / writes. The regions are identified by the mark 0x02.
964 static void mark_bbt_region(struct mtd_info
*mtd
, struct nand_bbt_descr
*td
)
966 struct nand_chip
*this = mtd_to_nand(mtd
);
967 int i
, j
, chips
, block
, nrblocks
, update
;
970 /* Do we have a bbt per chip? */
971 if (td
->options
& NAND_BBT_PERCHIP
) {
972 chips
= this->numchips
;
973 nrblocks
= (int)(this->chipsize
>> this->bbt_erase_shift
);
976 nrblocks
= (int)(mtd
->size
>> this->bbt_erase_shift
);
979 for (i
= 0; i
< chips
; i
++) {
980 if ((td
->options
& NAND_BBT_ABSPAGE
) ||
981 !(td
->options
& NAND_BBT_WRITE
)) {
982 if (td
->pages
[i
] == -1)
984 block
= td
->pages
[i
] >> (this->bbt_erase_shift
- this->page_shift
);
985 oldval
= bbt_get_entry(this, block
);
986 bbt_mark_entry(this, block
, BBT_BLOCK_RESERVED
);
987 if ((oldval
!= BBT_BLOCK_RESERVED
) &&
988 td
->reserved_block_code
)
989 nand_update_bbt(mtd
, (loff_t
)block
<<
990 this->bbt_erase_shift
);
994 if (td
->options
& NAND_BBT_LASTBLOCK
)
995 block
= ((i
+ 1) * nrblocks
) - td
->maxblocks
;
997 block
= i
* nrblocks
;
998 for (j
= 0; j
< td
->maxblocks
; j
++) {
999 oldval
= bbt_get_entry(this, block
);
1000 bbt_mark_entry(this, block
, BBT_BLOCK_RESERVED
);
1001 if (oldval
!= BBT_BLOCK_RESERVED
)
1006 * If we want reserved blocks to be recorded to flash, and some
1007 * new ones have been marked, then we need to update the stored
1008 * bbts. This should only happen once.
1010 if (update
&& td
->reserved_block_code
)
1011 nand_update_bbt(mtd
, (loff_t
)(block
- 1) <<
1012 this->bbt_erase_shift
);
1017 * verify_bbt_descr - verify the bad block description
1018 * @mtd: MTD device structure
1019 * @bd: the table to verify
1021 * This functions performs a few sanity checks on the bad block description
1024 static void verify_bbt_descr(struct mtd_info
*mtd
, struct nand_bbt_descr
*bd
)
1026 struct nand_chip
*this = mtd_to_nand(mtd
);
1034 pattern_len
= bd
->len
;
1035 bits
= bd
->options
& NAND_BBT_NRBITS_MSK
;
1037 BUG_ON((this->bbt_options
& NAND_BBT_NO_OOB
) &&
1038 !(this->bbt_options
& NAND_BBT_USE_FLASH
));
1041 if (bd
->options
& NAND_BBT_VERSION
)
1044 if (bd
->options
& NAND_BBT_NO_OOB
) {
1045 BUG_ON(!(this->bbt_options
& NAND_BBT_USE_FLASH
));
1046 BUG_ON(!(this->bbt_options
& NAND_BBT_NO_OOB
));
1048 if (bd
->options
& NAND_BBT_VERSION
)
1049 BUG_ON(bd
->veroffs
!= bd
->len
);
1050 BUG_ON(bd
->options
& NAND_BBT_SAVECONTENT
);
1053 if (bd
->options
& NAND_BBT_PERCHIP
)
1054 table_size
= this->chipsize
>> this->bbt_erase_shift
;
1056 table_size
= mtd
->size
>> this->bbt_erase_shift
;
1059 if (bd
->options
& NAND_BBT_NO_OOB
)
1060 table_size
+= pattern_len
;
1061 BUG_ON(table_size
> (1 << this->bbt_erase_shift
));
1065 * nand_scan_bbt - [NAND Interface] scan, find, read and maybe create bad block table(s)
1066 * @mtd: MTD device structure
1067 * @bd: descriptor for the good/bad block search pattern
1069 * The function checks, if a bad block table(s) is/are already available. If
1070 * not it scans the device for manufacturer marked good / bad blocks and writes
1071 * the bad block table(s) to the selected place.
1073 * The bad block table memory is allocated here. It must be freed by calling
1074 * the nand_free_bbt function.
1076 static int nand_scan_bbt(struct mtd_info
*mtd
, struct nand_bbt_descr
*bd
)
1078 struct nand_chip
*this = mtd_to_nand(mtd
);
1081 struct nand_bbt_descr
*td
= this->bbt_td
;
1082 struct nand_bbt_descr
*md
= this->bbt_md
;
1084 len
= (mtd
->size
>> (this->bbt_erase_shift
+ 2)) ? : 1;
1086 * Allocate memory (2bit per block) and clear the memory bad block
1089 this->bbt
= kzalloc(len
, GFP_KERNEL
);
1094 * If no primary table decriptor is given, scan the device to build a
1095 * memory based bad block table.
1098 if ((res
= nand_memory_bbt(mtd
, bd
))) {
1099 pr_err("nand_bbt: can't scan flash and build the RAM-based BBT\n");
1104 verify_bbt_descr(mtd
, td
);
1105 verify_bbt_descr(mtd
, md
);
1107 /* Allocate a temporary buffer for one eraseblock incl. oob */
1108 len
= (1 << this->bbt_erase_shift
);
1109 len
+= (len
>> this->page_shift
) * mtd
->oobsize
;
1116 /* Is the bbt at a given page? */
1117 if (td
->options
& NAND_BBT_ABSPAGE
) {
1118 read_abs_bbts(mtd
, buf
, td
, md
);
1120 /* Search the bad block table using a pattern in oob */
1121 search_read_bbts(mtd
, buf
, td
, md
);
1124 res
= check_create(mtd
, buf
, bd
);
1128 /* Prevent the bbt regions from erasing / writing */
1129 mark_bbt_region(mtd
, td
);
1131 mark_bbt_region(mtd
, md
);
1143 * nand_update_bbt - update bad block table(s)
1144 * @mtd: MTD device structure
1145 * @offs: the offset of the newly marked block
1147 * The function updates the bad block table(s).
1149 static int nand_update_bbt(struct mtd_info
*mtd
, loff_t offs
)
1151 struct nand_chip
*this = mtd_to_nand(mtd
);
1155 struct nand_bbt_descr
*td
= this->bbt_td
;
1156 struct nand_bbt_descr
*md
= this->bbt_md
;
1158 if (!this->bbt
|| !td
)
1161 /* Allocate a temporary buffer for one eraseblock incl. oob */
1162 len
= (1 << this->bbt_erase_shift
);
1163 len
+= (len
>> this->page_shift
) * mtd
->oobsize
;
1164 buf
= kmalloc(len
, GFP_KERNEL
);
1168 /* Do we have a bbt per chip? */
1169 if (td
->options
& NAND_BBT_PERCHIP
) {
1170 chip
= (int)(offs
>> this->chip_shift
);
1177 td
->version
[chip
]++;
1179 md
->version
[chip
]++;
1181 /* Write the bad block table to the device? */
1182 if (td
->options
& NAND_BBT_WRITE
) {
1183 res
= write_bbt(mtd
, buf
, td
, md
, chipsel
);
1187 /* Write the mirror bad block table to the device? */
1188 if (md
&& (md
->options
& NAND_BBT_WRITE
)) {
1189 res
= write_bbt(mtd
, buf
, md
, td
, chipsel
);
1198 * Define some generic bad / good block scan pattern which are used
1199 * while scanning a device for factory marked good / bad blocks.
1201 static uint8_t scan_ff_pattern
[] = { 0xff, 0xff };
1203 /* Generic flash bbt descriptors */
1204 static uint8_t bbt_pattern
[] = {'B', 'b', 't', '0' };
1205 static uint8_t mirror_pattern
[] = {'1', 't', 'b', 'B' };
1207 static struct nand_bbt_descr bbt_main_descr
= {
1208 .options
= NAND_BBT_LASTBLOCK
| NAND_BBT_CREATE
| NAND_BBT_WRITE
1209 | NAND_BBT_2BIT
| NAND_BBT_VERSION
| NAND_BBT_PERCHIP
,
1213 .maxblocks
= NAND_BBT_SCAN_MAXBLOCKS
,
1214 .pattern
= bbt_pattern
1217 static struct nand_bbt_descr bbt_mirror_descr
= {
1218 .options
= NAND_BBT_LASTBLOCK
| NAND_BBT_CREATE
| NAND_BBT_WRITE
1219 | NAND_BBT_2BIT
| NAND_BBT_VERSION
| NAND_BBT_PERCHIP
,
1223 .maxblocks
= NAND_BBT_SCAN_MAXBLOCKS
,
1224 .pattern
= mirror_pattern
1227 static struct nand_bbt_descr bbt_main_no_oob_descr
= {
1228 .options
= NAND_BBT_LASTBLOCK
| NAND_BBT_CREATE
| NAND_BBT_WRITE
1229 | NAND_BBT_2BIT
| NAND_BBT_VERSION
| NAND_BBT_PERCHIP
1233 .maxblocks
= NAND_BBT_SCAN_MAXBLOCKS
,
1234 .pattern
= bbt_pattern
1237 static struct nand_bbt_descr bbt_mirror_no_oob_descr
= {
1238 .options
= NAND_BBT_LASTBLOCK
| NAND_BBT_CREATE
| NAND_BBT_WRITE
1239 | NAND_BBT_2BIT
| NAND_BBT_VERSION
| NAND_BBT_PERCHIP
1243 .maxblocks
= NAND_BBT_SCAN_MAXBLOCKS
,
1244 .pattern
= mirror_pattern
1247 #define BADBLOCK_SCAN_MASK (~NAND_BBT_NO_OOB)
1249 * nand_create_badblock_pattern - [INTERN] Creates a BBT descriptor structure
1250 * @this: NAND chip to create descriptor for
1252 * This function allocates and initializes a nand_bbt_descr for BBM detection
1253 * based on the properties of @this. The new descriptor is stored in
1254 * this->badblock_pattern. Thus, this->badblock_pattern should be NULL when
1255 * passed to this function.
1257 static int nand_create_badblock_pattern(struct nand_chip
*this)
1259 struct nand_bbt_descr
*bd
;
1260 if (this->badblock_pattern
) {
1261 pr_warn("Bad block pattern already allocated; not replacing\n");
1264 bd
= kzalloc(sizeof(*bd
), GFP_KERNEL
);
1267 bd
->options
= this->bbt_options
& BADBLOCK_SCAN_MASK
;
1268 bd
->offs
= this->badblockpos
;
1269 bd
->len
= (this->options
& NAND_BUSWIDTH_16
) ? 2 : 1;
1270 bd
->pattern
= scan_ff_pattern
;
1271 bd
->options
|= NAND_BBT_DYNAMICSTRUCT
;
1272 this->badblock_pattern
= bd
;
1277 * nand_default_bbt - [NAND Interface] Select a default bad block table for the device
1278 * @mtd: MTD device structure
1280 * This function selects the default bad block table support for the device and
1281 * calls the nand_scan_bbt function.
1283 int nand_default_bbt(struct mtd_info
*mtd
)
1285 struct nand_chip
*this = mtd_to_nand(mtd
);
1288 /* Is a flash based bad block table requested? */
1289 if (this->bbt_options
& NAND_BBT_USE_FLASH
) {
1290 /* Use the default pattern descriptors */
1291 if (!this->bbt_td
) {
1292 if (this->bbt_options
& NAND_BBT_NO_OOB
) {
1293 this->bbt_td
= &bbt_main_no_oob_descr
;
1294 this->bbt_md
= &bbt_mirror_no_oob_descr
;
1296 this->bbt_td
= &bbt_main_descr
;
1297 this->bbt_md
= &bbt_mirror_descr
;
1301 this->bbt_td
= NULL
;
1302 this->bbt_md
= NULL
;
1305 if (!this->badblock_pattern
) {
1306 ret
= nand_create_badblock_pattern(this);
1311 return nand_scan_bbt(mtd
, this->badblock_pattern
);
1315 * nand_isreserved_bbt - [NAND Interface] Check if a block is reserved
1316 * @mtd: MTD device structure
1317 * @offs: offset in the device
1319 int nand_isreserved_bbt(struct mtd_info
*mtd
, loff_t offs
)
1321 struct nand_chip
*this = mtd_to_nand(mtd
);
1324 block
= (int)(offs
>> this->bbt_erase_shift
);
1325 return bbt_get_entry(this, block
) == BBT_BLOCK_RESERVED
;
1329 * nand_isbad_bbt - [NAND Interface] Check if a block is bad
1330 * @mtd: MTD device structure
1331 * @offs: offset in the device
1332 * @allowbbt: allow access to bad block table region
1334 int nand_isbad_bbt(struct mtd_info
*mtd
, loff_t offs
, int allowbbt
)
1336 struct nand_chip
*this = mtd_to_nand(mtd
);
1339 block
= (int)(offs
>> this->bbt_erase_shift
);
1340 res
= bbt_get_entry(this, block
);
1342 pr_debug("nand_isbad_bbt(): bbt info for offs 0x%08x: (block %d) 0x%02x\n",
1343 (unsigned int)offs
, block
, res
);
1346 case BBT_BLOCK_GOOD
:
1348 case BBT_BLOCK_WORN
:
1350 case BBT_BLOCK_RESERVED
:
1351 return allowbbt
? 0 : 1;
1357 * nand_markbad_bbt - [NAND Interface] Mark a block bad in the BBT
1358 * @mtd: MTD device structure
1359 * @offs: offset of the bad block
1361 int nand_markbad_bbt(struct mtd_info
*mtd
, loff_t offs
)
1363 struct nand_chip
*this = mtd_to_nand(mtd
);
1366 block
= (int)(offs
>> this->bbt_erase_shift
);
1368 /* Mark bad block in memory */
1369 bbt_mark_entry(this, block
, BBT_BLOCK_WORN
);
1371 /* Update flash-based bad block table */
1372 if (this->bbt_options
& NAND_BBT_USE_FLASH
)
1373 ret
= nand_update_bbt(mtd
, offs
);