xref: /openbmc/linux/include/linux/mtd/mtd.h (revision fa7f32422ea1ac276b45b96a540ed5981caaa61f)
1 /*
2  * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  *
18  */
19 
20 #ifndef __MTD_MTD_H__
21 #define __MTD_MTD_H__
22 
23 #include <linux/types.h>
24 #include <linux/uio.h>
25 #include <linux/notifier.h>
26 #include <linux/device.h>
27 
28 #include <mtd/mtd-abi.h>
29 
30 #include <asm/div64.h>
31 
32 #define MTD_ERASE_PENDING	0x01
33 #define MTD_ERASING		0x02
34 #define MTD_ERASE_SUSPEND	0x04
35 #define MTD_ERASE_DONE		0x08
36 #define MTD_ERASE_FAILED	0x10
37 
38 #define MTD_FAIL_ADDR_UNKNOWN -1LL
39 
40 /*
41  * If the erase fails, fail_addr might indicate exactly which block failed. If
42  * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level
43  * or was not specific to any particular block.
44  */
45 struct erase_info {
46 	struct mtd_info *mtd;
47 	uint64_t addr;
48 	uint64_t len;
49 	uint64_t fail_addr;
50 	u_long time;
51 	u_long retries;
52 	unsigned dev;
53 	unsigned cell;
54 	void (*callback) (struct erase_info *self);
55 	u_long priv;
56 	u_char state;
57 	struct erase_info *next;
58 };
59 
60 struct mtd_erase_region_info {
61 	uint64_t offset;		/* At which this region starts, from the beginning of the MTD */
62 	uint32_t erasesize;		/* For this region */
63 	uint32_t numblocks;		/* Number of blocks of erasesize in this region */
64 	unsigned long *lockmap;		/* If keeping bitmap of locks */
65 };
66 
67 /**
68  * struct mtd_oob_ops - oob operation operands
69  * @mode:	operation mode
70  *
71  * @len:	number of data bytes to write/read
72  *
73  * @retlen:	number of data bytes written/read
74  *
75  * @ooblen:	number of oob bytes to write/read
76  * @oobretlen:	number of oob bytes written/read
77  * @ooboffs:	offset of oob data in the oob area (only relevant when
78  *		mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)
79  * @datbuf:	data buffer - if NULL only oob data are read/written
80  * @oobbuf:	oob data buffer
81  *
82  * Note, it is allowed to read more than one OOB area at one go, but not write.
83  * The interface assumes that the OOB write requests program only one page's
84  * OOB area.
85  */
86 struct mtd_oob_ops {
87 	unsigned int	mode;
88 	size_t		len;
89 	size_t		retlen;
90 	size_t		ooblen;
91 	size_t		oobretlen;
92 	uint32_t	ooboffs;
93 	uint8_t		*datbuf;
94 	uint8_t		*oobbuf;
95 };
96 
97 #define MTD_MAX_OOBFREE_ENTRIES_LARGE	32
98 #define MTD_MAX_ECCPOS_ENTRIES_LARGE	640
99 /**
100  * struct mtd_oob_region - oob region definition
101  * @offset: region offset
102  * @length: region length
103  *
104  * This structure describes a region of the OOB area, and is used
105  * to retrieve ECC or free bytes sections.
106  * Each section is defined by an offset within the OOB area and a
107  * length.
108  */
109 struct mtd_oob_region {
110 	u32 offset;
111 	u32 length;
112 };
113 
114 /*
115  * struct mtd_ooblayout_ops - NAND OOB layout operations
116  * @ecc: function returning an ECC region in the OOB area.
117  *	 Should return -ERANGE if %section exceeds the total number of
118  *	 ECC sections.
119  * @free: function returning a free region in the OOB area.
120  *	  Should return -ERANGE if %section exceeds the total number of
121  *	  free sections.
122  */
123 struct mtd_ooblayout_ops {
124 	int (*ecc)(struct mtd_info *mtd, int section,
125 		   struct mtd_oob_region *oobecc);
126 	int (*free)(struct mtd_info *mtd, int section,
127 		    struct mtd_oob_region *oobfree);
128 };
129 
130 /**
131  * struct mtd_pairing_info - page pairing information
132  *
133  * @pair: pair id
134  * @group: group id
135  *
136  * The term "pair" is used here, even though TLC NANDs might group pages by 3
137  * (3 bits in a single cell). A pair should regroup all pages that are sharing
138  * the same cell. Pairs are then indexed in ascending order.
139  *
140  * @group is defining the position of a page in a given pair. It can also be
141  * seen as the bit position in the cell: page attached to bit 0 belongs to
142  * group 0, page attached to bit 1 belongs to group 1, etc.
143  *
144  * Example:
145  * The H27UCG8T2BTR-BC datasheet describes the following pairing scheme:
146  *
147  *		group-0		group-1
148  *
149  *  pair-0	page-0		page-4
150  *  pair-1	page-1		page-5
151  *  pair-2	page-2		page-8
152  *  ...
153  *  pair-127	page-251	page-255
154  *
155  *
156  * Note that the "group" and "pair" terms were extracted from Samsung and
157  * Hynix datasheets, and might be referenced under other names in other
158  * datasheets (Micron is describing this concept as "shared pages").
159  */
160 struct mtd_pairing_info {
161 	int pair;
162 	int group;
163 };
164 
165 /**
166  * struct mtd_pairing_scheme - page pairing scheme description
167  *
168  * @ngroups: number of groups. Should be related to the number of bits
169  *	     per cell.
170  * @get_info: converts a write-unit (page number within an erase block) into
171  *	      mtd_pairing information (pair + group). This function should
172  *	      fill the info parameter based on the wunit index or return
173  *	      -EINVAL if the wunit parameter is invalid.
174  * @get_wunit: converts pairing information into a write-unit (page) number.
175  *	       This function should return the wunit index pointed by the
176  *	       pairing information described in the info argument. It should
177  *	       return -EINVAL, if there's no wunit corresponding to the
178  *	       passed pairing information.
179  *
180  * See mtd_pairing_info documentation for a detailed explanation of the
181  * pair and group concepts.
182  *
183  * The mtd_pairing_scheme structure provides a generic solution to represent
184  * NAND page pairing scheme. Instead of exposing two big tables to do the
185  * write-unit <-> (pair + group) conversions, we ask the MTD drivers to
186  * implement the ->get_info() and ->get_wunit() functions.
187  *
188  * MTD users will then be able to query these information by using the
189  * mtd_pairing_info_to_wunit() and mtd_wunit_to_pairing_info() helpers.
190  *
191  * @ngroups is here to help MTD users iterating over all the pages in a
192  * given pair. This value can be retrieved by MTD users using the
193  * mtd_pairing_groups() helper.
194  *
195  * Examples are given in the mtd_pairing_info_to_wunit() and
196  * mtd_wunit_to_pairing_info() documentation.
197  */
198 struct mtd_pairing_scheme {
199 	int ngroups;
200 	int (*get_info)(struct mtd_info *mtd, int wunit,
201 			struct mtd_pairing_info *info);
202 	int (*get_wunit)(struct mtd_info *mtd,
203 			 const struct mtd_pairing_info *info);
204 };
205 
206 struct module;	/* only needed for owner field in mtd_info */
207 
208 struct mtd_info {
209 	u_char type;
210 	uint32_t flags;
211 	uint64_t size;	 // Total size of the MTD
212 
213 	/* "Major" erase size for the device. Naïve users may take this
214 	 * to be the only erase size available, or may use the more detailed
215 	 * information below if they desire
216 	 */
217 	uint32_t erasesize;
218 	/* Minimal writable flash unit size. In case of NOR flash it is 1 (even
219 	 * though individual bits can be cleared), in case of NAND flash it is
220 	 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
221 	 * it is of ECC block size, etc. It is illegal to have writesize = 0.
222 	 * Any driver registering a struct mtd_info must ensure a writesize of
223 	 * 1 or larger.
224 	 */
225 	uint32_t writesize;
226 
227 	/*
228 	 * Size of the write buffer used by the MTD. MTD devices having a write
229 	 * buffer can write multiple writesize chunks at a time. E.g. while
230 	 * writing 4 * writesize bytes to a device with 2 * writesize bytes
231 	 * buffer the MTD driver can (but doesn't have to) do 2 writesize
232 	 * operations, but not 4. Currently, all NANDs have writebufsize
233 	 * equivalent to writesize (NAND page size). Some NOR flashes do have
234 	 * writebufsize greater than writesize.
235 	 */
236 	uint32_t writebufsize;
237 
238 	uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
239 	uint32_t oobavail;  // Available OOB bytes per block
240 
241 	/*
242 	 * If erasesize is a power of 2 then the shift is stored in
243 	 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
244 	 */
245 	unsigned int erasesize_shift;
246 	unsigned int writesize_shift;
247 	/* Masks based on erasesize_shift and writesize_shift */
248 	unsigned int erasesize_mask;
249 	unsigned int writesize_mask;
250 
251 	/*
252 	 * read ops return -EUCLEAN if max number of bitflips corrected on any
253 	 * one region comprising an ecc step equals or exceeds this value.
254 	 * Settable by driver, else defaults to ecc_strength.  User can override
255 	 * in sysfs.  N.B. The meaning of the -EUCLEAN return code has changed;
256 	 * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
257 	 */
258 	unsigned int bitflip_threshold;
259 
260 	// Kernel-only stuff starts here.
261 	const char *name;
262 	int index;
263 
264 	/* OOB layout description */
265 	const struct mtd_ooblayout_ops *ooblayout;
266 
267 	/* NAND pairing scheme, only provided for MLC/TLC NANDs */
268 	const struct mtd_pairing_scheme *pairing;
269 
270 	/* the ecc step size. */
271 	unsigned int ecc_step_size;
272 
273 	/* max number of correctible bit errors per ecc step */
274 	unsigned int ecc_strength;
275 
276 	/* Data for variable erase regions. If numeraseregions is zero,
277 	 * it means that the whole device has erasesize as given above.
278 	 */
279 	int numeraseregions;
280 	struct mtd_erase_region_info *eraseregions;
281 
282 	/*
283 	 * Do not call via these pointers, use corresponding mtd_*()
284 	 * wrappers instead.
285 	 */
286 	int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
287 	int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
288 		       size_t *retlen, void **virt, resource_size_t *phys);
289 	int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
290 	unsigned long (*_get_unmapped_area) (struct mtd_info *mtd,
291 					     unsigned long len,
292 					     unsigned long offset,
293 					     unsigned long flags);
294 	int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
295 		      size_t *retlen, u_char *buf);
296 	int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
297 		       size_t *retlen, const u_char *buf);
298 	int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
299 			     size_t *retlen, const u_char *buf);
300 	int (*_read_oob) (struct mtd_info *mtd, loff_t from,
301 			  struct mtd_oob_ops *ops);
302 	int (*_write_oob) (struct mtd_info *mtd, loff_t to,
303 			   struct mtd_oob_ops *ops);
304 	int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,
305 				    size_t *retlen, struct otp_info *buf);
306 	int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
307 				    size_t len, size_t *retlen, u_char *buf);
308 	int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,
309 				    size_t *retlen, struct otp_info *buf);
310 	int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
311 				    size_t len, size_t *retlen, u_char *buf);
312 	int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
313 				     size_t len, size_t *retlen, u_char *buf);
314 	int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
315 				    size_t len);
316 	int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
317 			unsigned long count, loff_t to, size_t *retlen);
318 	void (*_sync) (struct mtd_info *mtd);
319 	int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
320 	int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
321 	int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
322 	int (*_block_isreserved) (struct mtd_info *mtd, loff_t ofs);
323 	int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
324 	int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
325 	int (*_suspend) (struct mtd_info *mtd);
326 	void (*_resume) (struct mtd_info *mtd);
327 	void (*_reboot) (struct mtd_info *mtd);
328 	/*
329 	 * If the driver is something smart, like UBI, it may need to maintain
330 	 * its own reference counting. The below functions are only for driver.
331 	 */
332 	int (*_get_device) (struct mtd_info *mtd);
333 	void (*_put_device) (struct mtd_info *mtd);
334 
335 	/* Backing device capabilities for this device
336 	 * - provides mmap capabilities
337 	 */
338 	struct backing_dev_info *backing_dev_info;
339 
340 	struct notifier_block reboot_notifier;  /* default mode before reboot */
341 
342 	/* ECC status information */
343 	struct mtd_ecc_stats ecc_stats;
344 	/* Subpage shift (NAND) */
345 	int subpage_sft;
346 
347 	void *priv;
348 
349 	struct module *owner;
350 	struct device dev;
351 	int usecount;
352 };
353 
354 int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
355 		      struct mtd_oob_region *oobecc);
356 int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
357 				 int *section,
358 				 struct mtd_oob_region *oobregion);
359 int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
360 			       const u8 *oobbuf, int start, int nbytes);
361 int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
362 			       u8 *oobbuf, int start, int nbytes);
363 int mtd_ooblayout_free(struct mtd_info *mtd, int section,
364 		       struct mtd_oob_region *oobfree);
365 int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
366 				const u8 *oobbuf, int start, int nbytes);
367 int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
368 				u8 *oobbuf, int start, int nbytes);
369 int mtd_ooblayout_count_freebytes(struct mtd_info *mtd);
370 int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd);
371 
372 static inline void mtd_set_ooblayout(struct mtd_info *mtd,
373 				     const struct mtd_ooblayout_ops *ooblayout)
374 {
375 	mtd->ooblayout = ooblayout;
376 }
377 
378 static inline void mtd_set_pairing_scheme(struct mtd_info *mtd,
379 				const struct mtd_pairing_scheme *pairing)
380 {
381 	mtd->pairing = pairing;
382 }
383 
384 static inline void mtd_set_of_node(struct mtd_info *mtd,
385 				   struct device_node *np)
386 {
387 	mtd->dev.of_node = np;
388 }
389 
390 static inline struct device_node *mtd_get_of_node(struct mtd_info *mtd)
391 {
392 	return mtd->dev.of_node;
393 }
394 
395 static inline int mtd_oobavail(struct mtd_info *mtd, struct mtd_oob_ops *ops)
396 {
397 	return ops->mode == MTD_OPS_AUTO_OOB ? mtd->oobavail : mtd->oobsize;
398 }
399 
400 int mtd_wunit_to_pairing_info(struct mtd_info *mtd, int wunit,
401 			      struct mtd_pairing_info *info);
402 int mtd_pairing_info_to_wunit(struct mtd_info *mtd,
403 			      const struct mtd_pairing_info *info);
404 int mtd_pairing_groups(struct mtd_info *mtd);
405 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
406 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
407 	      void **virt, resource_size_t *phys);
408 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
409 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
410 				    unsigned long offset, unsigned long flags);
411 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
412 	     u_char *buf);
413 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
414 	      const u_char *buf);
415 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
416 		    const u_char *buf);
417 
418 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
419 int mtd_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops);
420 
421 int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
422 			   struct otp_info *buf);
423 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
424 			   size_t *retlen, u_char *buf);
425 int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
426 			   struct otp_info *buf);
427 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
428 			   size_t *retlen, u_char *buf);
429 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
430 			    size_t *retlen, u_char *buf);
431 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
432 
433 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
434 	       unsigned long count, loff_t to, size_t *retlen);
435 
436 static inline void mtd_sync(struct mtd_info *mtd)
437 {
438 	if (mtd->_sync)
439 		mtd->_sync(mtd);
440 }
441 
442 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
443 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
444 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
445 int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs);
446 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs);
447 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs);
448 
449 static inline int mtd_suspend(struct mtd_info *mtd)
450 {
451 	return mtd->_suspend ? mtd->_suspend(mtd) : 0;
452 }
453 
454 static inline void mtd_resume(struct mtd_info *mtd)
455 {
456 	if (mtd->_resume)
457 		mtd->_resume(mtd);
458 }
459 
460 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
461 {
462 	if (mtd->erasesize_shift)
463 		return sz >> mtd->erasesize_shift;
464 	do_div(sz, mtd->erasesize);
465 	return sz;
466 }
467 
468 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
469 {
470 	if (mtd->erasesize_shift)
471 		return sz & mtd->erasesize_mask;
472 	return do_div(sz, mtd->erasesize);
473 }
474 
475 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
476 {
477 	if (mtd->writesize_shift)
478 		return sz >> mtd->writesize_shift;
479 	do_div(sz, mtd->writesize);
480 	return sz;
481 }
482 
483 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
484 {
485 	if (mtd->writesize_shift)
486 		return sz & mtd->writesize_mask;
487 	return do_div(sz, mtd->writesize);
488 }
489 
490 static inline int mtd_wunit_per_eb(struct mtd_info *mtd)
491 {
492 	return mtd->erasesize / mtd->writesize;
493 }
494 
495 static inline int mtd_offset_to_wunit(struct mtd_info *mtd, loff_t offs)
496 {
497 	return mtd_div_by_ws(mtd_mod_by_eb(offs, mtd), mtd);
498 }
499 
500 static inline loff_t mtd_wunit_to_offset(struct mtd_info *mtd, loff_t base,
501 					 int wunit)
502 {
503 	return base + (wunit * mtd->writesize);
504 }
505 
506 
507 static inline int mtd_has_oob(const struct mtd_info *mtd)
508 {
509 	return mtd->_read_oob && mtd->_write_oob;
510 }
511 
512 static inline int mtd_type_is_nand(const struct mtd_info *mtd)
513 {
514 	return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;
515 }
516 
517 static inline int mtd_can_have_bb(const struct mtd_info *mtd)
518 {
519 	return !!mtd->_block_isbad;
520 }
521 
522 	/* Kernel-side ioctl definitions */
523 
524 struct mtd_partition;
525 struct mtd_part_parser_data;
526 
527 extern int mtd_device_parse_register(struct mtd_info *mtd,
528 				     const char * const *part_probe_types,
529 				     struct mtd_part_parser_data *parser_data,
530 				     const struct mtd_partition *defparts,
531 				     int defnr_parts);
532 #define mtd_device_register(master, parts, nr_parts)	\
533 	mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
534 extern int mtd_device_unregister(struct mtd_info *master);
535 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
536 extern int __get_mtd_device(struct mtd_info *mtd);
537 extern void __put_mtd_device(struct mtd_info *mtd);
538 extern struct mtd_info *get_mtd_device_nm(const char *name);
539 extern void put_mtd_device(struct mtd_info *mtd);
540 
541 
542 struct mtd_notifier {
543 	void (*add)(struct mtd_info *mtd);
544 	void (*remove)(struct mtd_info *mtd);
545 	struct list_head list;
546 };
547 
548 
549 extern void register_mtd_user (struct mtd_notifier *new);
550 extern int unregister_mtd_user (struct mtd_notifier *old);
551 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
552 
553 void mtd_erase_callback(struct erase_info *instr);
554 
555 static inline int mtd_is_bitflip(int err) {
556 	return err == -EUCLEAN;
557 }
558 
559 static inline int mtd_is_eccerr(int err) {
560 	return err == -EBADMSG;
561 }
562 
563 static inline int mtd_is_bitflip_or_eccerr(int err) {
564 	return mtd_is_bitflip(err) || mtd_is_eccerr(err);
565 }
566 
567 unsigned mtd_mmap_capabilities(struct mtd_info *mtd);
568 
569 #endif /* __MTD_MTD_H__ */
570