xref: /openbmc/linux/include/linux/mtd/mtd.h (revision a2cce7a9)
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 	__u32 oobavail;
109 	struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
110 };
111 
112 struct module;	/* only needed for owner field in mtd_info */
113 
114 struct mtd_info {
115 	u_char type;
116 	uint32_t flags;
117 	uint64_t size;	 // Total size of the MTD
118 
119 	/* "Major" erase size for the device. Naïve users may take this
120 	 * to be the only erase size available, or may use the more detailed
121 	 * information below if they desire
122 	 */
123 	uint32_t erasesize;
124 	/* Minimal writable flash unit size. In case of NOR flash it is 1 (even
125 	 * though individual bits can be cleared), in case of NAND flash it is
126 	 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
127 	 * it is of ECC block size, etc. It is illegal to have writesize = 0.
128 	 * Any driver registering a struct mtd_info must ensure a writesize of
129 	 * 1 or larger.
130 	 */
131 	uint32_t writesize;
132 
133 	/*
134 	 * Size of the write buffer used by the MTD. MTD devices having a write
135 	 * buffer can write multiple writesize chunks at a time. E.g. while
136 	 * writing 4 * writesize bytes to a device with 2 * writesize bytes
137 	 * buffer the MTD driver can (but doesn't have to) do 2 writesize
138 	 * operations, but not 4. Currently, all NANDs have writebufsize
139 	 * equivalent to writesize (NAND page size). Some NOR flashes do have
140 	 * writebufsize greater than writesize.
141 	 */
142 	uint32_t writebufsize;
143 
144 	uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
145 	uint32_t oobavail;  // Available OOB bytes per block
146 
147 	/*
148 	 * If erasesize is a power of 2 then the shift is stored in
149 	 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
150 	 */
151 	unsigned int erasesize_shift;
152 	unsigned int writesize_shift;
153 	/* Masks based on erasesize_shift and writesize_shift */
154 	unsigned int erasesize_mask;
155 	unsigned int writesize_mask;
156 
157 	/*
158 	 * read ops return -EUCLEAN if max number of bitflips corrected on any
159 	 * one region comprising an ecc step equals or exceeds this value.
160 	 * Settable by driver, else defaults to ecc_strength.  User can override
161 	 * in sysfs.  N.B. The meaning of the -EUCLEAN return code has changed;
162 	 * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
163 	 */
164 	unsigned int bitflip_threshold;
165 
166 	// Kernel-only stuff starts here.
167 	const char *name;
168 	int index;
169 
170 	/* ECC layout structure pointer - read only! */
171 	struct nand_ecclayout *ecclayout;
172 
173 	/* the ecc step size. */
174 	unsigned int ecc_step_size;
175 
176 	/* max number of correctible bit errors per ecc step */
177 	unsigned int ecc_strength;
178 
179 	/* Data for variable erase regions. If numeraseregions is zero,
180 	 * it means that the whole device has erasesize as given above.
181 	 */
182 	int numeraseregions;
183 	struct mtd_erase_region_info *eraseregions;
184 
185 	/*
186 	 * Do not call via these pointers, use corresponding mtd_*()
187 	 * wrappers instead.
188 	 */
189 	int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
190 	int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
191 		       size_t *retlen, void **virt, resource_size_t *phys);
192 	int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
193 	unsigned long (*_get_unmapped_area) (struct mtd_info *mtd,
194 					     unsigned long len,
195 					     unsigned long offset,
196 					     unsigned long flags);
197 	int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
198 		      size_t *retlen, u_char *buf);
199 	int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
200 		       size_t *retlen, const u_char *buf);
201 	int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
202 			     size_t *retlen, const u_char *buf);
203 	int (*_read_oob) (struct mtd_info *mtd, loff_t from,
204 			  struct mtd_oob_ops *ops);
205 	int (*_write_oob) (struct mtd_info *mtd, loff_t to,
206 			   struct mtd_oob_ops *ops);
207 	int (*_get_fact_prot_info) (struct mtd_info *mtd, size_t len,
208 				    size_t *retlen, struct otp_info *buf);
209 	int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
210 				    size_t len, size_t *retlen, u_char *buf);
211 	int (*_get_user_prot_info) (struct mtd_info *mtd, size_t len,
212 				    size_t *retlen, struct otp_info *buf);
213 	int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
214 				    size_t len, size_t *retlen, u_char *buf);
215 	int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
216 				     size_t len, size_t *retlen, u_char *buf);
217 	int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
218 				    size_t len);
219 	int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
220 			unsigned long count, loff_t to, size_t *retlen);
221 	void (*_sync) (struct mtd_info *mtd);
222 	int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
223 	int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
224 	int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
225 	int (*_block_isreserved) (struct mtd_info *mtd, loff_t ofs);
226 	int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
227 	int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
228 	int (*_suspend) (struct mtd_info *mtd);
229 	void (*_resume) (struct mtd_info *mtd);
230 	void (*_reboot) (struct mtd_info *mtd);
231 	/*
232 	 * If the driver is something smart, like UBI, it may need to maintain
233 	 * its own reference counting. The below functions are only for driver.
234 	 */
235 	int (*_get_device) (struct mtd_info *mtd);
236 	void (*_put_device) (struct mtd_info *mtd);
237 
238 	/* Backing device capabilities for this device
239 	 * - provides mmap capabilities
240 	 */
241 	struct backing_dev_info *backing_dev_info;
242 
243 	struct notifier_block reboot_notifier;  /* default mode before reboot */
244 
245 	/* ECC status information */
246 	struct mtd_ecc_stats ecc_stats;
247 	/* Subpage shift (NAND) */
248 	int subpage_sft;
249 
250 	void *priv;
251 
252 	struct module *owner;
253 	struct device dev;
254 	int usecount;
255 };
256 
257 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
258 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
259 	      void **virt, resource_size_t *phys);
260 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
261 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
262 				    unsigned long offset, unsigned long flags);
263 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
264 	     u_char *buf);
265 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
266 	      const u_char *buf);
267 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
268 		    const u_char *buf);
269 
270 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
271 
272 static inline int mtd_write_oob(struct mtd_info *mtd, loff_t to,
273 				struct mtd_oob_ops *ops)
274 {
275 	ops->retlen = ops->oobretlen = 0;
276 	if (!mtd->_write_oob)
277 		return -EOPNOTSUPP;
278 	if (!(mtd->flags & MTD_WRITEABLE))
279 		return -EROFS;
280 	return mtd->_write_oob(mtd, to, ops);
281 }
282 
283 int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
284 			   struct otp_info *buf);
285 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
286 			   size_t *retlen, u_char *buf);
287 int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
288 			   struct otp_info *buf);
289 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
290 			   size_t *retlen, u_char *buf);
291 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
292 			    size_t *retlen, u_char *buf);
293 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
294 
295 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
296 	       unsigned long count, loff_t to, size_t *retlen);
297 
298 static inline void mtd_sync(struct mtd_info *mtd)
299 {
300 	if (mtd->_sync)
301 		mtd->_sync(mtd);
302 }
303 
304 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
305 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
306 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
307 int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs);
308 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs);
309 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs);
310 
311 static inline int mtd_suspend(struct mtd_info *mtd)
312 {
313 	return mtd->_suspend ? mtd->_suspend(mtd) : 0;
314 }
315 
316 static inline void mtd_resume(struct mtd_info *mtd)
317 {
318 	if (mtd->_resume)
319 		mtd->_resume(mtd);
320 }
321 
322 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
323 {
324 	if (mtd->erasesize_shift)
325 		return sz >> mtd->erasesize_shift;
326 	do_div(sz, mtd->erasesize);
327 	return sz;
328 }
329 
330 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
331 {
332 	if (mtd->erasesize_shift)
333 		return sz & mtd->erasesize_mask;
334 	return do_div(sz, mtd->erasesize);
335 }
336 
337 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
338 {
339 	if (mtd->writesize_shift)
340 		return sz >> mtd->writesize_shift;
341 	do_div(sz, mtd->writesize);
342 	return sz;
343 }
344 
345 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
346 {
347 	if (mtd->writesize_shift)
348 		return sz & mtd->writesize_mask;
349 	return do_div(sz, mtd->writesize);
350 }
351 
352 static inline int mtd_has_oob(const struct mtd_info *mtd)
353 {
354 	return mtd->_read_oob && mtd->_write_oob;
355 }
356 
357 static inline int mtd_type_is_nand(const struct mtd_info *mtd)
358 {
359 	return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;
360 }
361 
362 static inline int mtd_can_have_bb(const struct mtd_info *mtd)
363 {
364 	return !!mtd->_block_isbad;
365 }
366 
367 	/* Kernel-side ioctl definitions */
368 
369 struct mtd_partition;
370 struct mtd_part_parser_data;
371 
372 extern int mtd_device_parse_register(struct mtd_info *mtd,
373 				     const char * const *part_probe_types,
374 				     struct mtd_part_parser_data *parser_data,
375 				     const struct mtd_partition *defparts,
376 				     int defnr_parts);
377 #define mtd_device_register(master, parts, nr_parts)	\
378 	mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
379 extern int mtd_device_unregister(struct mtd_info *master);
380 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
381 extern int __get_mtd_device(struct mtd_info *mtd);
382 extern void __put_mtd_device(struct mtd_info *mtd);
383 extern struct mtd_info *get_mtd_device_nm(const char *name);
384 extern void put_mtd_device(struct mtd_info *mtd);
385 
386 
387 struct mtd_notifier {
388 	void (*add)(struct mtd_info *mtd);
389 	void (*remove)(struct mtd_info *mtd);
390 	struct list_head list;
391 };
392 
393 
394 extern void register_mtd_user (struct mtd_notifier *new);
395 extern int unregister_mtd_user (struct mtd_notifier *old);
396 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
397 
398 void mtd_erase_callback(struct erase_info *instr);
399 
400 static inline int mtd_is_bitflip(int err) {
401 	return err == -EUCLEAN;
402 }
403 
404 static inline int mtd_is_eccerr(int err) {
405 	return err == -EBADMSG;
406 }
407 
408 static inline int mtd_is_bitflip_or_eccerr(int err) {
409 	return mtd_is_bitflip(err) || mtd_is_eccerr(err);
410 }
411 
412 unsigned mtd_mmap_capabilities(struct mtd_info *mtd);
413 
414 #endif /* __MTD_MTD_H__ */
415