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1/*
2 * NAND family Bad Block Management (BBM) header file
3 * - Bad Block Table (BBT) implementation
4 *
5 * Copyright © 2005 Samsung Electronics
6 * Kyungmin Park <kyungmin.park@samsung.com>
7 *
8 * Copyright © 2000-2005
9 * Thomas Gleixner <tglx@linuxtronix.de>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
24 *
25 */
26#ifndef __LINUX_MTD_BBM_H
27#define __LINUX_MTD_BBM_H
28
29/* The maximum number of NAND chips in an array */
30#define NAND_MAX_CHIPS 8
31
32/**
33 * struct nand_bbt_descr - bad block table descriptor
34 * @options: options for this descriptor
35 * @pages: the page(s) where we find the bbt, used with option BBT_ABSPAGE
36 * when bbt is searched, then we store the found bbts pages here.
37 * Its an array and supports up to 8 chips now
38 * @offs: offset of the pattern in the oob area of the page
39 * @veroffs: offset of the bbt version counter in the oob are of the page
40 * @version: version read from the bbt page during scan
41 * @len: length of the pattern, if 0 no pattern check is performed
42 * @maxblocks: maximum number of blocks to search for a bbt. This number of
43 * blocks is reserved at the end of the device where the tables are
44 * written.
45 * @reserved_block_code: if non-0, this pattern denotes a reserved (rather than
46 * bad) block in the stored bbt
47 * @pattern: pattern to identify bad block table or factory marked good /
48 * bad blocks, can be NULL, if len = 0
49 *
50 * Descriptor for the bad block table marker and the descriptor for the
51 * pattern which identifies good and bad blocks. The assumption is made
52 * that the pattern and the version count are always located in the oob area
53 * of the first block.
54 */
55struct nand_bbt_descr {
56 int options;
57 int pages[NAND_MAX_CHIPS];
58 int offs;
59 int veroffs;
60 uint8_t version[NAND_MAX_CHIPS];
61 int len;
62 int maxblocks;
63 int reserved_block_code;
64 uint8_t *pattern;
65};
66
67/* Options for the bad block table descriptors */
68
69/* The number of bits used per block in the bbt on the device */
70#define NAND_BBT_NRBITS_MSK 0x0000000F
71#define NAND_BBT_1BIT 0x00000001
72#define NAND_BBT_2BIT 0x00000002
73#define NAND_BBT_4BIT 0x00000004
74#define NAND_BBT_8BIT 0x00000008
75/* The bad block table is in the last good block of the device */
76#define NAND_BBT_LASTBLOCK 0x00000010
77/* The bbt is at the given page, else we must scan for the bbt */
78#define NAND_BBT_ABSPAGE 0x00000020
79/* bbt is stored per chip on multichip devices */
80#define NAND_BBT_PERCHIP 0x00000080
81/* bbt has a version counter at offset veroffs */
82#define NAND_BBT_VERSION 0x00000100
83/* Create a bbt if none exists */
84#define NAND_BBT_CREATE 0x00000200
85/*
86 * Create an empty BBT with no vendor information. Vendor's information may be
87 * unavailable, for example, if the NAND controller has a different data and OOB
88 * layout or if this information is already purged. Must be used in conjunction
89 * with NAND_BBT_CREATE.
90 */
91#define NAND_BBT_CREATE_EMPTY 0x00000400
92/* Write bbt if neccecary */
93#define NAND_BBT_WRITE 0x00002000
94/* Read and write back block contents when writing bbt */
95#define NAND_BBT_SAVECONTENT 0x00004000
96/* Search good / bad pattern on the first and the second page */
97#define NAND_BBT_SCAN2NDPAGE 0x00008000
98/* Search good / bad pattern on the last page of the eraseblock */
99#define NAND_BBT_SCANLASTPAGE 0x00010000
100/*
101 * Use a flash based bad block table. By default, OOB identifier is saved in
102 * OOB area. This option is passed to the default bad block table function.
103 */
104#define NAND_BBT_USE_FLASH 0x00020000
105/*
106 * Do not store flash based bad block table marker in the OOB area; store it
107 * in-band.
108 */
109#define NAND_BBT_NO_OOB 0x00040000
110/*
111 * Do not write new bad block markers to OOB; useful, e.g., when ECC covers
112 * entire spare area. Must be used with NAND_BBT_USE_FLASH.
113 */
114#define NAND_BBT_NO_OOB_BBM 0x00080000
115
116/*
117 * Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr
118 * was allocated dynamicaly and must be freed in nand_release(). Has no meaning
119 * in nand_chip.bbt_options.
120 */
121#define NAND_BBT_DYNAMICSTRUCT 0x80000000
122
123/* The maximum number of blocks to scan for a bbt */
124#define NAND_BBT_SCAN_MAXBLOCKS 4
125
126/*
127 * Constants for oob configuration
128 */
129#define NAND_SMALL_BADBLOCK_POS 5
130#define NAND_LARGE_BADBLOCK_POS 0
131#define ONENAND_BADBLOCK_POS 0
132
133/*
134 * Bad block scanning errors
135 */
136#define ONENAND_BBT_READ_ERROR 1
137#define ONENAND_BBT_READ_ECC_ERROR 2
138#define ONENAND_BBT_READ_FATAL_ERROR 4
139
140/**
141 * struct bbm_info - [GENERIC] Bad Block Table data structure
142 * @bbt_erase_shift: [INTERN] number of address bits in a bbt entry
143 * @badblockpos: [INTERN] position of the bad block marker in the oob area
144 * @options: options for this descriptor
145 * @bbt: [INTERN] bad block table pointer
146 * @isbad_bbt: function to determine if a block is bad
147 * @badblock_pattern: [REPLACEABLE] bad block scan pattern used for
148 * initial bad block scan
149 * @priv: [OPTIONAL] pointer to private bbm date
150 */
151struct bbm_info {
152 int bbt_erase_shift;
153 int badblockpos;
154 int options;
155
156 uint8_t *bbt;
157
158 int (*isbad_bbt)(struct mtd_info *mtd, loff_t ofs, int allowbbt);
159
160 /* TODO Add more NAND specific fileds */
161 struct nand_bbt_descr *badblock_pattern;
162
163 void *priv;
164};
165
166/* OneNAND BBT interface */
167extern int onenand_default_bbt(struct mtd_info *mtd);
168
169#endif /* __LINUX_MTD_BBM_H */