xref: /openbmc/linux/include/linux/mtd/mtd.h (revision fa0a497b)
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  * Internal ECC layout control structure. For historical reasons, there is a
101  * similar, smaller struct nand_ecclayout_user (in mtd-abi.h) that is retained
102  * for export to user-space via the ECCGETLAYOUT ioctl.
103  * nand_ecclayout should be expandable in the future simply by the above macros.
104  */
105 struct nand_ecclayout {
106 	__u32 eccbytes;
107 	__u32 eccpos[MTD_MAX_ECCPOS_ENTRIES_LARGE];
108 	struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
109 };
110 
111 struct module;	/* only needed for owner field in mtd_info */
112 
113 struct mtd_info {
114 	u_char type;
115 	uint32_t flags;
116 	uint64_t size;	 // Total size of the MTD
117 
118 	/* "Major" erase size for the device. Naïve users may take this
119 	 * to be the only erase size available, or may use the more detailed
120 	 * information below if they desire
121 	 */
122 	uint32_t erasesize;
123 	/* Minimal writable flash unit size. In case of NOR flash it is 1 (even
124 	 * though individual bits can be cleared), in case of NAND flash it is
125 	 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
126 	 * it is of ECC block size, etc. It is illegal to have writesize = 0.
127 	 * Any driver registering a struct mtd_info must ensure a writesize of
128 	 * 1 or larger.
129 	 */
130 	uint32_t writesize;
131 
132 	/*
133 	 * Size of the write buffer used by the MTD. MTD devices having a write
134 	 * buffer can write multiple writesize chunks at a time. E.g. while
135 	 * writing 4 * writesize bytes to a device with 2 * writesize bytes
136 	 * buffer the MTD driver can (but doesn't have to) do 2 writesize
137 	 * operations, but not 4. Currently, all NANDs have writebufsize
138 	 * equivalent to writesize (NAND page size). Some NOR flashes do have
139 	 * writebufsize greater than writesize.
140 	 */
141 	uint32_t writebufsize;
142 
143 	uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
144 	uint32_t oobavail;  // Available OOB bytes per block
145 
146 	/*
147 	 * If erasesize is a power of 2 then the shift is stored in
148 	 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
149 	 */
150 	unsigned int erasesize_shift;
151 	unsigned int writesize_shift;
152 	/* Masks based on erasesize_shift and writesize_shift */
153 	unsigned int erasesize_mask;
154 	unsigned int writesize_mask;
155 
156 	/*
157 	 * read ops return -EUCLEAN if max number of bitflips corrected on any
158 	 * one region comprising an ecc step equals or exceeds this value.
159 	 * Settable by driver, else defaults to ecc_strength.  User can override
160 	 * in sysfs.  N.B. The meaning of the -EUCLEAN return code has changed;
161 	 * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
162 	 */
163 	unsigned int bitflip_threshold;
164 
165 	// Kernel-only stuff starts here.
166 	const char *name;
167 	int index;
168 
169 	/* ECC layout structure pointer - read only! */
170 	struct nand_ecclayout *ecclayout;
171 
172 	/* the ecc step size. */
173 	unsigned int ecc_step_size;
174 
175 	/* max number of correctible bit errors per ecc step */
176 	unsigned int ecc_strength;
177 
178 	/* Data for variable erase regions. If numeraseregions is zero,
179 	 * it means that the whole device has erasesize as given above.
180 	 */
181 	int numeraseregions;
182 	struct mtd_erase_region_info *eraseregions;
183 
184 	/*
185 	 * Do not call via these pointers, use corresponding mtd_*()
186 	 * wrappers instead.
187 	 */
188 	int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
189 	int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
190 		       size_t *retlen, void **virt, resource_size_t *phys);
191 	int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
192 	unsigned long (*_get_unmapped_area) (struct mtd_info *mtd,
193 					     unsigned long len,
194 					     unsigned long offset,
195 					     unsigned long flags);
196 	int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
197 		      size_t *retlen, u_char *buf);
198 	int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
199 		       size_t *retlen, const u_char *buf);
200 	int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
201 			     size_t *retlen, const u_char *buf);
202 	int (*_read_oob) (struct mtd_info *mtd, loff_t from,
203 			  struct mtd_oob_ops *ops);
204 	int (*_write_oob) (struct mtd_info *mtd, loff_t to,
205 			   struct mtd_oob_ops *ops);
206 	int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,
207 				    size_t *retlen, struct otp_info *buf);
208 	int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
209 				    size_t len, size_t *retlen, u_char *buf);
210 	int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,
211 				    size_t *retlen, struct otp_info *buf);
212 	int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
213 				    size_t len, size_t *retlen, u_char *buf);
214 	int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
215 				     size_t len, size_t *retlen, u_char *buf);
216 	int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
217 				    size_t len);
218 	int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
219 			unsigned long count, loff_t to, size_t *retlen);
220 	void (*_sync) (struct mtd_info *mtd);
221 	int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
222 	int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
223 	int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
224 	int (*_block_isreserved) (struct mtd_info *mtd, loff_t ofs);
225 	int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
226 	int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
227 	int (*_suspend) (struct mtd_info *mtd);
228 	void (*_resume) (struct mtd_info *mtd);
229 	void (*_reboot) (struct mtd_info *mtd);
230 	/*
231 	 * If the driver is something smart, like UBI, it may need to maintain
232 	 * its own reference counting. The below functions are only for driver.
233 	 */
234 	int (*_get_device) (struct mtd_info *mtd);
235 	void (*_put_device) (struct mtd_info *mtd);
236 
237 	/* Backing device capabilities for this device
238 	 * - provides mmap capabilities
239 	 */
240 	struct backing_dev_info *backing_dev_info;
241 
242 	struct notifier_block reboot_notifier;  /* default mode before reboot */
243 
244 	/* ECC status information */
245 	struct mtd_ecc_stats ecc_stats;
246 	/* Subpage shift (NAND) */
247 	int subpage_sft;
248 
249 	void *priv;
250 
251 	struct module *owner;
252 	struct device dev;
253 	int usecount;
254 };
255 
256 static inline void mtd_set_of_node(struct mtd_info *mtd,
257 				   struct device_node *np)
258 {
259 	mtd->dev.of_node = np;
260 }
261 
262 static inline struct device_node *mtd_get_of_node(struct mtd_info *mtd)
263 {
264 	return mtd->dev.of_node;
265 }
266 
267 static inline int mtd_oobavail(struct mtd_info *mtd, struct mtd_oob_ops *ops)
268 {
269 	return ops->mode == MTD_OPS_AUTO_OOB ? mtd->oobavail : mtd->oobsize;
270 }
271 
272 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
273 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
274 	      void **virt, resource_size_t *phys);
275 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
276 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
277 				    unsigned long offset, unsigned long flags);
278 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
279 	     u_char *buf);
280 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
281 	      const u_char *buf);
282 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
283 		    const u_char *buf);
284 
285 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
286 
287 static inline int mtd_write_oob(struct mtd_info *mtd, loff_t to,
288 				struct mtd_oob_ops *ops)
289 {
290 	ops->retlen = ops->oobretlen = 0;
291 	if (!mtd->_write_oob)
292 		return -EOPNOTSUPP;
293 	if (!(mtd->flags & MTD_WRITEABLE))
294 		return -EROFS;
295 	return mtd->_write_oob(mtd, to, ops);
296 }
297 
298 int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
299 			   struct otp_info *buf);
300 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
301 			   size_t *retlen, u_char *buf);
302 int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
303 			   struct otp_info *buf);
304 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
305 			   size_t *retlen, u_char *buf);
306 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
307 			    size_t *retlen, u_char *buf);
308 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
309 
310 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
311 	       unsigned long count, loff_t to, size_t *retlen);
312 
313 static inline void mtd_sync(struct mtd_info *mtd)
314 {
315 	if (mtd->_sync)
316 		mtd->_sync(mtd);
317 }
318 
319 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
320 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
321 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
322 int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs);
323 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs);
324 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs);
325 
326 static inline int mtd_suspend(struct mtd_info *mtd)
327 {
328 	return mtd->_suspend ? mtd->_suspend(mtd) : 0;
329 }
330 
331 static inline void mtd_resume(struct mtd_info *mtd)
332 {
333 	if (mtd->_resume)
334 		mtd->_resume(mtd);
335 }
336 
337 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
338 {
339 	if (mtd->erasesize_shift)
340 		return sz >> mtd->erasesize_shift;
341 	do_div(sz, mtd->erasesize);
342 	return sz;
343 }
344 
345 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
346 {
347 	if (mtd->erasesize_shift)
348 		return sz & mtd->erasesize_mask;
349 	return do_div(sz, mtd->erasesize);
350 }
351 
352 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
353 {
354 	if (mtd->writesize_shift)
355 		return sz >> mtd->writesize_shift;
356 	do_div(sz, mtd->writesize);
357 	return sz;
358 }
359 
360 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
361 {
362 	if (mtd->writesize_shift)
363 		return sz & mtd->writesize_mask;
364 	return do_div(sz, mtd->writesize);
365 }
366 
367 static inline int mtd_has_oob(const struct mtd_info *mtd)
368 {
369 	return mtd->_read_oob && mtd->_write_oob;
370 }
371 
372 static inline int mtd_type_is_nand(const struct mtd_info *mtd)
373 {
374 	return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;
375 }
376 
377 static inline int mtd_can_have_bb(const struct mtd_info *mtd)
378 {
379 	return !!mtd->_block_isbad;
380 }
381 
382 	/* Kernel-side ioctl definitions */
383 
384 struct mtd_partition;
385 struct mtd_part_parser_data;
386 
387 extern int mtd_device_parse_register(struct mtd_info *mtd,
388 				     const char * const *part_probe_types,
389 				     struct mtd_part_parser_data *parser_data,
390 				     const struct mtd_partition *defparts,
391 				     int defnr_parts);
392 #define mtd_device_register(master, parts, nr_parts)	\
393 	mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
394 extern int mtd_device_unregister(struct mtd_info *master);
395 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
396 extern int __get_mtd_device(struct mtd_info *mtd);
397 extern void __put_mtd_device(struct mtd_info *mtd);
398 extern struct mtd_info *get_mtd_device_nm(const char *name);
399 extern void put_mtd_device(struct mtd_info *mtd);
400 
401 
402 struct mtd_notifier {
403 	void (*add)(struct mtd_info *mtd);
404 	void (*remove)(struct mtd_info *mtd);
405 	struct list_head list;
406 };
407 
408 
409 extern void register_mtd_user (struct mtd_notifier *new);
410 extern int unregister_mtd_user (struct mtd_notifier *old);
411 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
412 
413 void mtd_erase_callback(struct erase_info *instr);
414 
415 static inline int mtd_is_bitflip(int err) {
416 	return err == -EUCLEAN;
417 }
418 
419 static inline int mtd_is_eccerr(int err) {
420 	return err == -EBADMSG;
421 }
422 
423 static inline int mtd_is_bitflip_or_eccerr(int err) {
424 	return mtd_is_bitflip(err) || mtd_is_eccerr(err);
425 }
426 
427 unsigned mtd_mmap_capabilities(struct mtd_info *mtd);
428 
429 #endif /* __MTD_MTD_H__ */
430