xref: /openbmc/u-boot/include/linux/mtd/nand.h (revision 08ab4e17)
1 /*
2  *  linux/include/linux/mtd/nand.h
3  *
4  *  Copyright (c) 2000 David Woodhouse <dwmw2@mvhi.com>
5  *                     Steven J. Hill <sjhill@realitydiluted.com>
6  *		       Thomas Gleixner <tglx@linutronix.de>
7  *
8  * $Id: nand.h,v 1.74 2005/09/15 13:58:50 vwool Exp $
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  *
14  * Info:
15  *	Contains standard defines and IDs for NAND flash devices
16  *
17  * Changelog:
18  *	See git changelog.
19  */
20 #ifndef __LINUX_MTD_NAND_H
21 #define __LINUX_MTD_NAND_H
22 
23 /* XXX U-BOOT XXX */
24 #if 0
25 #include <linux/wait.h>
26 #include <linux/spinlock.h>
27 #include <linux/mtd/mtd.h>
28 #endif
29 
30 #include "config.h"
31 
32 #include "linux/mtd/compat.h"
33 #include "linux/mtd/mtd.h"
34 
35 
36 struct mtd_info;
37 /* Scan and identify a NAND device */
38 extern int nand_scan (struct mtd_info *mtd, int max_chips);
39 /* Separate phases of nand_scan(), allowing board driver to intervene
40  * and override command or ECC setup according to flash type */
41 extern int nand_scan_ident(struct mtd_info *mtd, int max_chips);
42 extern int nand_scan_tail(struct mtd_info *mtd);
43 
44 /* Free resources held by the NAND device */
45 extern void nand_release (struct mtd_info *mtd);
46 
47 /* Internal helper for board drivers which need to override command function */
48 extern void nand_wait_ready(struct mtd_info *mtd);
49 
50 /* The maximum number of NAND chips in an array */
51 #ifndef NAND_MAX_CHIPS
52 #define NAND_MAX_CHIPS		8
53 #endif
54 
55 /* This constant declares the max. oobsize / page, which
56  * is supported now. If you add a chip with bigger oobsize/page
57  * adjust this accordingly.
58  */
59 #define NAND_MAX_OOBSIZE	128
60 #define NAND_MAX_PAGESIZE	4096
61 
62 /*
63  * Constants for hardware specific CLE/ALE/NCE function
64  *
65  * These are bits which can be or'ed to set/clear multiple
66  * bits in one go.
67  */
68 /* Select the chip by setting nCE to low */
69 #define NAND_NCE		0x01
70 /* Select the command latch by setting CLE to high */
71 #define NAND_CLE		0x02
72 /* Select the address latch by setting ALE to high */
73 #define NAND_ALE		0x04
74 
75 #define NAND_CTRL_CLE		(NAND_NCE | NAND_CLE)
76 #define NAND_CTRL_ALE		(NAND_NCE | NAND_ALE)
77 #define NAND_CTRL_CHANGE	0x80
78 
79 /*
80  * Standard NAND flash commands
81  */
82 #define NAND_CMD_READ0		0
83 #define NAND_CMD_READ1		1
84 #define NAND_CMD_RNDOUT		5
85 #define NAND_CMD_PAGEPROG	0x10
86 #define NAND_CMD_READOOB	0x50
87 #define NAND_CMD_ERASE1		0x60
88 #define NAND_CMD_STATUS		0x70
89 #define NAND_CMD_STATUS_MULTI	0x71
90 #define NAND_CMD_SEQIN		0x80
91 #define NAND_CMD_RNDIN		0x85
92 #define NAND_CMD_READID		0x90
93 #define NAND_CMD_ERASE2		0xd0
94 #define NAND_CMD_RESET		0xff
95 
96 /* Extended commands for large page devices */
97 #define NAND_CMD_READSTART	0x30
98 #define NAND_CMD_RNDOUTSTART	0xE0
99 #define NAND_CMD_CACHEDPROG	0x15
100 
101 /* Extended commands for AG-AND device */
102 /*
103  * Note: the command for NAND_CMD_DEPLETE1 is really 0x00 but
104  *       there is no way to distinguish that from NAND_CMD_READ0
105  *       until the remaining sequence of commands has been completed
106  *       so add a high order bit and mask it off in the command.
107  */
108 #define NAND_CMD_DEPLETE1	0x100
109 #define NAND_CMD_DEPLETE2	0x38
110 #define NAND_CMD_STATUS_MULTI	0x71
111 #define NAND_CMD_STATUS_ERROR	0x72
112 /* multi-bank error status (banks 0-3) */
113 #define NAND_CMD_STATUS_ERROR0	0x73
114 #define NAND_CMD_STATUS_ERROR1	0x74
115 #define NAND_CMD_STATUS_ERROR2	0x75
116 #define NAND_CMD_STATUS_ERROR3	0x76
117 #define NAND_CMD_STATUS_RESET	0x7f
118 #define NAND_CMD_STATUS_CLEAR	0xff
119 
120 #define NAND_CMD_NONE		-1
121 
122 /* Status bits */
123 #define NAND_STATUS_FAIL	0x01
124 #define NAND_STATUS_FAIL_N1	0x02
125 #define NAND_STATUS_TRUE_READY	0x20
126 #define NAND_STATUS_READY	0x40
127 #define NAND_STATUS_WP		0x80
128 
129 /*
130  * Constants for ECC_MODES
131  */
132 typedef enum {
133 	NAND_ECC_NONE,
134 	NAND_ECC_SOFT,
135 	NAND_ECC_HW,
136 	NAND_ECC_HW_SYNDROME,
137 } nand_ecc_modes_t;
138 
139 /*
140  * Constants for Hardware ECC
141  */
142 /* Reset Hardware ECC for read */
143 #define NAND_ECC_READ		0
144 /* Reset Hardware ECC for write */
145 #define NAND_ECC_WRITE		1
146 /* Enable Hardware ECC before syndrom is read back from flash */
147 #define NAND_ECC_READSYN	2
148 
149 /* Bit mask for flags passed to do_nand_read_ecc */
150 #define NAND_GET_DEVICE		0x80
151 
152 
153 /* Option constants for bizarre disfunctionality and real
154 *  features
155 */
156 /* Chip can not auto increment pages */
157 #define NAND_NO_AUTOINCR	0x00000001
158 /* Buswitdh is 16 bit */
159 #define NAND_BUSWIDTH_16	0x00000002
160 /* Device supports partial programming without padding */
161 #define NAND_NO_PADDING		0x00000004
162 /* Chip has cache program function */
163 #define NAND_CACHEPRG		0x00000008
164 /* Chip has copy back function */
165 #define NAND_COPYBACK		0x00000010
166 /* AND Chip which has 4 banks and a confusing page / block
167  * assignment. See Renesas datasheet for further information */
168 #define NAND_IS_AND		0x00000020
169 /* Chip has a array of 4 pages which can be read without
170  * additional ready /busy waits */
171 #define NAND_4PAGE_ARRAY	0x00000040
172 /* Chip requires that BBT is periodically rewritten to prevent
173  * bits from adjacent blocks from 'leaking' in altering data.
174  * This happens with the Renesas AG-AND chips, possibly others.  */
175 #define BBT_AUTO_REFRESH	0x00000080
176 /* Chip does not require ready check on read. True
177  * for all large page devices, as they do not support
178  * autoincrement.*/
179 #define NAND_NO_READRDY		0x00000100
180 /* Chip does not allow subpage writes */
181 #define NAND_NO_SUBPAGE_WRITE	0x00000200
182 
183 
184 /* Options valid for Samsung large page devices */
185 #define NAND_SAMSUNG_LP_OPTIONS \
186 	(NAND_NO_PADDING | NAND_CACHEPRG | NAND_COPYBACK)
187 
188 /* Macros to identify the above */
189 #define NAND_CANAUTOINCR(chip) (!(chip->options & NAND_NO_AUTOINCR))
190 #define NAND_MUST_PAD(chip) (!(chip->options & NAND_NO_PADDING))
191 #define NAND_HAS_CACHEPROG(chip) ((chip->options & NAND_CACHEPRG))
192 #define NAND_HAS_COPYBACK(chip) ((chip->options & NAND_COPYBACK))
193 
194 /* Mask to zero out the chip options, which come from the id table */
195 #define NAND_CHIPOPTIONS_MSK	(0x0000ffff & ~NAND_NO_AUTOINCR)
196 
197 /* Non chip related options */
198 /* Use a flash based bad block table. This option is passed to the
199  * default bad block table function. */
200 #define NAND_USE_FLASH_BBT	0x00010000
201 /* This option skips the bbt scan during initialization. */
202 #define NAND_SKIP_BBTSCAN	0x00020000
203 /* This option is defined if the board driver allocates its own buffers
204    (e.g. because it needs them DMA-coherent */
205 #define NAND_OWN_BUFFERS	0x00040000
206 /* Options set by nand scan */
207 /* bbt has already been read */
208 #define NAND_BBT_SCANNED	0x40000000
209 /* Nand scan has allocated controller struct */
210 #define NAND_CONTROLLER_ALLOC	0x80000000
211 
212 /* Cell info constants */
213 #define NAND_CI_CHIPNR_MSK	0x03
214 #define NAND_CI_CELLTYPE_MSK	0x0C
215 
216 /* Keep gcc happy */
217 struct nand_chip;
218 
219 /**
220  * struct nand_hw_control - Control structure for hardware controller (e.g ECC generator) shared among independent devices
221  * @lock:               protection lock
222  * @active:		the mtd device which holds the controller currently
223  * @wq:			wait queue to sleep on if a NAND operation is in progress
224  *                      used instead of the per chip wait queue when a hw controller is available
225  */
226 struct nand_hw_control {
227 /* XXX U-BOOT XXX */
228 #if 0
229 	spinlock_t	 lock;
230 	wait_queue_head_t wq;
231 #endif
232 	struct nand_chip *active;
233 };
234 
235 /**
236  * struct nand_ecc_ctrl - Control structure for ecc
237  * @mode:	ecc mode
238  * @steps:	number of ecc steps per page
239  * @size:	data bytes per ecc step
240  * @bytes:	ecc bytes per step
241  * @total:	total number of ecc bytes per page
242  * @prepad:	padding information for syndrome based ecc generators
243  * @postpad:	padding information for syndrome based ecc generators
244  * @layout:	ECC layout control struct pointer
245  * @hwctl:	function to control hardware ecc generator. Must only
246  *		be provided if an hardware ECC is available
247  * @calculate:	function for ecc calculation or readback from ecc hardware
248  * @correct:	function for ecc correction, matching to ecc generator (sw/hw)
249  * @read_page_raw:	function to read a raw page without ECC
250  * @write_page_raw:	function to write a raw page without ECC
251  * @read_page:	function to read a page according to the ecc generator requirements
252  * @write_page:	function to write a page according to the ecc generator requirements
253  * @read_oob:	function to read chip OOB data
254  * @write_oob:	function to write chip OOB data
255  */
256 struct nand_ecc_ctrl {
257 	nand_ecc_modes_t	mode;
258 	int			steps;
259 	int			size;
260 	int			bytes;
261 	int			total;
262 	int			prepad;
263 	int			postpad;
264 	struct nand_ecclayout	*layout;
265 	void			(*hwctl)(struct mtd_info *mtd, int mode);
266 	int			(*calculate)(struct mtd_info *mtd,
267 					     const uint8_t *dat,
268 					     uint8_t *ecc_code);
269 	int			(*correct)(struct mtd_info *mtd, uint8_t *dat,
270 					   uint8_t *read_ecc,
271 					   uint8_t *calc_ecc);
272 	int			(*read_page_raw)(struct mtd_info *mtd,
273 						 struct nand_chip *chip,
274 						 uint8_t *buf);
275 	void			(*write_page_raw)(struct mtd_info *mtd,
276 						  struct nand_chip *chip,
277 						  const uint8_t *buf);
278 	int			(*read_page)(struct mtd_info *mtd,
279 					     struct nand_chip *chip,
280 					     uint8_t *buf);
281 	void			(*write_page)(struct mtd_info *mtd,
282 					      struct nand_chip *chip,
283 					      const uint8_t *buf);
284 	int			(*read_oob)(struct mtd_info *mtd,
285 					    struct nand_chip *chip,
286 					    int page,
287 					    int sndcmd);
288 	int			(*write_oob)(struct mtd_info *mtd,
289 					     struct nand_chip *chip,
290 					     int page);
291 };
292 
293 /**
294  * struct nand_buffers - buffer structure for read/write
295  * @ecccalc:	buffer for calculated ecc
296  * @ecccode:	buffer for ecc read from flash
297  * @databuf:	buffer for data - dynamically sized
298  *
299  * Do not change the order of buffers. databuf and oobrbuf must be in
300  * consecutive order.
301  */
302 struct nand_buffers {
303 	uint8_t	ecccalc[NAND_MAX_OOBSIZE];
304 	uint8_t	ecccode[NAND_MAX_OOBSIZE];
305 	uint8_t databuf[NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE];
306 };
307 
308 /**
309  * struct nand_chip - NAND Private Flash Chip Data
310  * @IO_ADDR_R:		[BOARDSPECIFIC] address to read the 8 I/O lines of the flash device
311  * @IO_ADDR_W:		[BOARDSPECIFIC] address to write the 8 I/O lines of the flash device
312  * @read_byte:		[REPLACEABLE] read one byte from the chip
313  * @read_word:		[REPLACEABLE] read one word from the chip
314  * @write_buf:		[REPLACEABLE] write data from the buffer to the chip
315  * @read_buf:		[REPLACEABLE] read data from the chip into the buffer
316  * @verify_buf:		[REPLACEABLE] verify buffer contents against the chip data
317  * @select_chip:	[REPLACEABLE] select chip nr
318  * @block_bad:		[REPLACEABLE] check, if the block is bad
319  * @block_markbad:	[REPLACEABLE] mark the block bad
320  * @cmd_ctrl:		[BOARDSPECIFIC] hardwarespecific funtion for controlling
321  *			ALE/CLE/nCE. Also used to write command and address
322  * @dev_ready:		[BOARDSPECIFIC] hardwarespecific function for accesing device ready/busy line
323  *			If set to NULL no access to ready/busy is available and the ready/busy information
324  *			is read from the chip status register
325  * @cmdfunc:		[REPLACEABLE] hardwarespecific function for writing commands to the chip
326  * @waitfunc:		[REPLACEABLE] hardwarespecific function for wait on ready
327  * @ecc:		[BOARDSPECIFIC] ecc control ctructure
328  * @buffers:		buffer structure for read/write
329  * @hwcontrol:		platform-specific hardware control structure
330  * @ops:		oob operation operands
331  * @erase_cmd:		[INTERN] erase command write function, selectable due to AND support
332  * @scan_bbt:		[REPLACEABLE] function to scan bad block table
333  * @chip_delay:		[BOARDSPECIFIC] chip dependent delay for transfering data from array to read regs (tR)
334  * @wq:			[INTERN] wait queue to sleep on if a NAND operation is in progress
335  * @state:		[INTERN] the current state of the NAND device
336  * @oob_poi:		poison value buffer
337  * @page_shift:		[INTERN] number of address bits in a page (column address bits)
338  * @phys_erase_shift:	[INTERN] number of address bits in a physical eraseblock
339  * @bbt_erase_shift:	[INTERN] number of address bits in a bbt entry
340  * @chip_shift:		[INTERN] number of address bits in one chip
341  * @datbuf:		[INTERN] internal buffer for one page + oob
342  * @oobbuf:		[INTERN] oob buffer for one eraseblock
343  * @oobdirty:		[INTERN] indicates that oob_buf must be reinitialized
344  * @data_poi:		[INTERN] pointer to a data buffer
345  * @options:		[BOARDSPECIFIC] various chip options. They can partly be set to inform nand_scan about
346  *			special functionality. See the defines for further explanation
347  * @badblockpos:	[INTERN] position of the bad block marker in the oob area
348  * @cellinfo:		[INTERN] MLC/multichip data from chip ident
349  * @numchips:		[INTERN] number of physical chips
350  * @chipsize:		[INTERN] the size of one chip for multichip arrays
351  * @pagemask:		[INTERN] page number mask = number of (pages / chip) - 1
352  * @pagebuf:		[INTERN] holds the pagenumber which is currently in data_buf
353  * @subpagesize:	[INTERN] holds the subpagesize
354  * @ecclayout:		[REPLACEABLE] the default ecc placement scheme
355  * @bbt:		[INTERN] bad block table pointer
356  * @bbt_td:		[REPLACEABLE] bad block table descriptor for flash lookup
357  * @bbt_md:		[REPLACEABLE] bad block table mirror descriptor
358  * @badblock_pattern:	[REPLACEABLE] bad block scan pattern used for initial bad block scan
359  * @controller:		[REPLACEABLE] a pointer to a hardware controller structure
360  *			which is shared among multiple independend devices
361  * @priv:		[OPTIONAL] pointer to private chip date
362  * @errstat:		[OPTIONAL] hardware specific function to perform additional error status checks
363  *			(determine if errors are correctable)
364  * @write_page:		[REPLACEABLE] High-level page write function
365  */
366 
367 struct nand_chip {
368 	void  __iomem	*IO_ADDR_R;
369 	void  __iomem	*IO_ADDR_W;
370 
371 	uint8_t		(*read_byte)(struct mtd_info *mtd);
372 	u16		(*read_word)(struct mtd_info *mtd);
373 	void		(*write_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
374 	void		(*read_buf)(struct mtd_info *mtd, uint8_t *buf, int len);
375 	int		(*verify_buf)(struct mtd_info *mtd, const uint8_t *buf, int len);
376 	void		(*select_chip)(struct mtd_info *mtd, int chip);
377 	int		(*block_bad)(struct mtd_info *mtd, loff_t ofs, int getchip);
378 	int		(*block_markbad)(struct mtd_info *mtd, loff_t ofs);
379 	void		(*cmd_ctrl)(struct mtd_info *mtd, int dat,
380 				    unsigned int ctrl);
381 	int		(*dev_ready)(struct mtd_info *mtd);
382 	void		(*cmdfunc)(struct mtd_info *mtd, unsigned command, int column, int page_addr);
383 	int		(*waitfunc)(struct mtd_info *mtd, struct nand_chip *this);
384 	void		(*erase_cmd)(struct mtd_info *mtd, int page);
385 	int		(*scan_bbt)(struct mtd_info *mtd);
386 	int		(*errstat)(struct mtd_info *mtd, struct nand_chip *this, int state, int status, int page);
387 	int		(*write_page)(struct mtd_info *mtd, struct nand_chip *chip,
388 				      const uint8_t *buf, int page, int cached, int raw);
389 
390 	int		chip_delay;
391 	unsigned int	options;
392 
393 	int		page_shift;
394 	int		phys_erase_shift;
395 	int		bbt_erase_shift;
396 	int		chip_shift;
397 	int		numchips;
398 	unsigned long	chipsize;
399 	int		pagemask;
400 	int		pagebuf;
401 	int		subpagesize;
402 	uint8_t		cellinfo;
403 	int		badblockpos;
404 
405 	int 		state;
406 
407 	uint8_t		*oob_poi;
408 	struct nand_hw_control  *controller;
409 	struct nand_ecclayout	*ecclayout;
410 
411 	struct nand_ecc_ctrl ecc;
412 	struct nand_buffers *buffers;
413 
414 	struct nand_hw_control hwcontrol;
415 
416 	struct mtd_oob_ops ops;
417 
418 	uint8_t		*bbt;
419 	struct nand_bbt_descr	*bbt_td;
420 	struct nand_bbt_descr	*bbt_md;
421 
422 	struct nand_bbt_descr	*badblock_pattern;
423 
424 	void		*priv;
425 };
426 
427 /*
428  * NAND Flash Manufacturer ID Codes
429  */
430 #define NAND_MFR_TOSHIBA	0x98
431 #define NAND_MFR_SAMSUNG	0xec
432 #define NAND_MFR_FUJITSU	0x04
433 #define NAND_MFR_NATIONAL	0x8f
434 #define NAND_MFR_RENESAS	0x07
435 #define NAND_MFR_STMICRO	0x20
436 #define NAND_MFR_HYNIX		0xad
437 #define NAND_MFR_MICRON		0x2c
438 
439 /**
440  * struct nand_flash_dev - NAND Flash Device ID Structure
441  * @name:	Identify the device type
442  * @id:		device ID code
443  * @pagesize:	Pagesize in bytes. Either 256 or 512 or 0
444  *		If the pagesize is 0, then the real pagesize
445  *		and the eraseize are determined from the
446  *		extended id bytes in the chip
447  * @erasesize:	Size of an erase block in the flash device.
448  * @chipsize:	Total chipsize in Mega Bytes
449  * @options:	Bitfield to store chip relevant options
450  */
451 struct nand_flash_dev {
452 	char *name;
453 	int id;
454 	unsigned long pagesize;
455 	unsigned long chipsize;
456 	unsigned long erasesize;
457 	unsigned long options;
458 };
459 
460 /**
461  * struct nand_manufacturers - NAND Flash Manufacturer ID Structure
462  * @name:	Manufacturer name
463  * @id:		manufacturer ID code of device.
464 */
465 struct nand_manufacturers {
466 	int id;
467 	char * name;
468 };
469 
470 extern struct nand_flash_dev nand_flash_ids[];
471 extern struct nand_manufacturers nand_manuf_ids[];
472 
473 #ifndef NAND_MAX_CHIPS
474 #define NAND_MAX_CHIPS 8
475 #endif
476 
477 /**
478  * struct nand_bbt_descr - bad block table descriptor
479  * @options:	options for this descriptor
480  * @pages:	the page(s) where we find the bbt, used with option BBT_ABSPAGE
481  *		when bbt is searched, then we store the found bbts pages here.
482  *		Its an array and supports up to 8 chips now
483  * @offs:	offset of the pattern in the oob area of the page
484  * @veroffs:	offset of the bbt version counter in the oob are of the page
485  * @version:	version read from the bbt page during scan
486  * @len:	length of the pattern, if 0 no pattern check is performed
487  * @maxblocks:	maximum number of blocks to search for a bbt. This number of
488  *		blocks is reserved at the end of the device where the tables are
489  *		written.
490  * @reserved_block_code: if non-0, this pattern denotes a reserved (rather than
491  *              bad) block in the stored bbt
492  * @pattern:	pattern to identify bad block table or factory marked good /
493  *		bad blocks, can be NULL, if len = 0
494  *
495  * Descriptor for the bad block table marker and the descriptor for the
496  * pattern which identifies good and bad blocks. The assumption is made
497  * that the pattern and the version count are always located in the oob area
498  * of the first block.
499  */
500 struct nand_bbt_descr {
501 	int	options;
502 	int	pages[NAND_MAX_CHIPS];
503 	int	offs;
504 	int	veroffs;
505 	uint8_t	version[NAND_MAX_CHIPS];
506 	int	len;
507 	int	maxblocks;
508 	int	reserved_block_code;
509 	uint8_t	*pattern;
510 };
511 
512 /* Options for the bad block table descriptors */
513 
514 /* The number of bits used per block in the bbt on the device */
515 #define NAND_BBT_NRBITS_MSK	0x0000000F
516 #define NAND_BBT_1BIT		0x00000001
517 #define NAND_BBT_2BIT		0x00000002
518 #define NAND_BBT_4BIT		0x00000004
519 #define NAND_BBT_8BIT		0x00000008
520 /* The bad block table is in the last good block of the device */
521 #define	NAND_BBT_LASTBLOCK	0x00000010
522 /* The bbt is at the given page, else we must scan for the bbt */
523 #define NAND_BBT_ABSPAGE	0x00000020
524 /* The bbt is at the given page, else we must scan for the bbt */
525 #define NAND_BBT_SEARCH		0x00000040
526 /* bbt is stored per chip on multichip devices */
527 #define NAND_BBT_PERCHIP	0x00000080
528 /* bbt has a version counter at offset veroffs */
529 #define NAND_BBT_VERSION	0x00000100
530 /* Create a bbt if none axists */
531 #define NAND_BBT_CREATE		0x00000200
532 /* Search good / bad pattern through all pages of a block */
533 #define NAND_BBT_SCANALLPAGES	0x00000400
534 /* Scan block empty during good / bad block scan */
535 #define NAND_BBT_SCANEMPTY	0x00000800
536 /* Write bbt if neccecary */
537 #define NAND_BBT_WRITE		0x00001000
538 /* Read and write back block contents when writing bbt */
539 #define NAND_BBT_SAVECONTENT	0x00002000
540 /* Search good / bad pattern on the first and the second page */
541 #define NAND_BBT_SCAN2NDPAGE	0x00004000
542 
543 /* The maximum number of blocks to scan for a bbt */
544 #define NAND_BBT_SCAN_MAXBLOCKS	4
545 
546 extern int nand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd);
547 extern int nand_update_bbt(struct mtd_info *mtd, loff_t offs);
548 extern int nand_default_bbt(struct mtd_info *mtd);
549 extern int nand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt);
550 extern int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
551 			   int allowbbt);
552 extern int nand_do_read(struct mtd_info *mtd, loff_t from, size_t len,
553 			size_t * retlen, uint8_t * buf);
554 
555 /*
556 * Constants for oob configuration
557 */
558 #define NAND_SMALL_BADBLOCK_POS		5
559 #define NAND_LARGE_BADBLOCK_POS		0
560 
561 /**
562  * struct platform_nand_chip - chip level device structure
563  * @nr_chips:		max. number of chips to scan for
564  * @chip_offset:	chip number offset
565  * @nr_partitions:	number of partitions pointed to by partitions (or zero)
566  * @partitions:		mtd partition list
567  * @chip_delay:		R/B delay value in us
568  * @options:		Option flags, e.g. 16bit buswidth
569  * @ecclayout:		ecc layout info structure
570  * @part_probe_types:	NULL-terminated array of probe types
571  * @priv:		hardware controller specific settings
572  */
573 struct platform_nand_chip {
574 	int			nr_chips;
575 	int			chip_offset;
576 	int			nr_partitions;
577 	struct mtd_partition	*partitions;
578 	struct nand_ecclayout	*ecclayout;
579 	int			chip_delay;
580 	unsigned int		options;
581 	const char		**part_probe_types;
582 	void			*priv;
583 };
584 
585 /**
586  * struct platform_nand_ctrl - controller level device structure
587  * @hwcontrol:		platform specific hardware control structure
588  * @dev_ready:		platform specific function to read ready/busy pin
589  * @select_chip:	platform specific chip select function
590  * @cmd_ctrl:		platform specific function for controlling
591  *			ALE/CLE/nCE. Also used to write command and address
592  * @priv:		private data to transport driver specific settings
593  *
594  * All fields are optional and depend on the hardware driver requirements
595  */
596 struct platform_nand_ctrl {
597 	void		(*hwcontrol)(struct mtd_info *mtd, int cmd);
598 	int		(*dev_ready)(struct mtd_info *mtd);
599 	void		(*select_chip)(struct mtd_info *mtd, int chip);
600 	void		(*cmd_ctrl)(struct mtd_info *mtd, int dat,
601 				    unsigned int ctrl);
602 	void		*priv;
603 };
604 
605 /**
606  * struct platform_nand_data - container structure for platform-specific data
607  * @chip:		chip level chip structure
608  * @ctrl:		controller level device structure
609  */
610 struct platform_nand_data {
611 	struct platform_nand_chip	chip;
612 	struct platform_nand_ctrl	ctrl;
613 };
614 
615 /* Some helpers to access the data structures */
616 static inline
617 struct platform_nand_chip *get_platform_nandchip(struct mtd_info *mtd)
618 {
619 	struct nand_chip *chip = mtd->priv;
620 
621 	return chip->priv;
622 }
623 
624 #endif /* __LINUX_MTD_NAND_H */
625