xref: /openbmc/linux/include/linux/mtd/mtd.h (revision f7777dcc)
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_CHAR_MAJOR 90
33 #define MTD_BLOCK_MAJOR 31
34 
35 #define MTD_ERASE_PENDING	0x01
36 #define MTD_ERASING		0x02
37 #define MTD_ERASE_SUSPEND	0x04
38 #define MTD_ERASE_DONE		0x08
39 #define MTD_ERASE_FAILED	0x10
40 
41 #define MTD_FAIL_ADDR_UNKNOWN -1LL
42 
43 /*
44  * If the erase fails, fail_addr might indicate exactly which block failed. If
45  * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level
46  * or was not specific to any particular block.
47  */
48 struct erase_info {
49 	struct mtd_info *mtd;
50 	uint64_t addr;
51 	uint64_t len;
52 	uint64_t fail_addr;
53 	u_long time;
54 	u_long retries;
55 	unsigned dev;
56 	unsigned cell;
57 	void (*callback) (struct erase_info *self);
58 	u_long priv;
59 	u_char state;
60 	struct erase_info *next;
61 };
62 
63 struct mtd_erase_region_info {
64 	uint64_t offset;		/* At which this region starts, from the beginning of the MTD */
65 	uint32_t erasesize;		/* For this region */
66 	uint32_t numblocks;		/* Number of blocks of erasesize in this region */
67 	unsigned long *lockmap;		/* If keeping bitmap of locks */
68 };
69 
70 /**
71  * struct mtd_oob_ops - oob operation operands
72  * @mode:	operation mode
73  *
74  * @len:	number of data bytes to write/read
75  *
76  * @retlen:	number of data bytes written/read
77  *
78  * @ooblen:	number of oob bytes to write/read
79  * @oobretlen:	number of oob bytes written/read
80  * @ooboffs:	offset of oob data in the oob area (only relevant when
81  *		mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)
82  * @datbuf:	data buffer - if NULL only oob data are read/written
83  * @oobbuf:	oob data buffer
84  *
85  * Note, it is allowed to read more than one OOB area at one go, but not write.
86  * The interface assumes that the OOB write requests program only one page's
87  * OOB area.
88  */
89 struct mtd_oob_ops {
90 	unsigned int	mode;
91 	size_t		len;
92 	size_t		retlen;
93 	size_t		ooblen;
94 	size_t		oobretlen;
95 	uint32_t	ooboffs;
96 	uint8_t		*datbuf;
97 	uint8_t		*oobbuf;
98 };
99 
100 #define MTD_MAX_OOBFREE_ENTRIES_LARGE	32
101 #define MTD_MAX_ECCPOS_ENTRIES_LARGE	640
102 /*
103  * Internal ECC layout control structure. For historical reasons, there is a
104  * similar, smaller struct nand_ecclayout_user (in mtd-abi.h) that is retained
105  * for export to user-space via the ECCGETLAYOUT ioctl.
106  * nand_ecclayout should be expandable in the future simply by the above macros.
107  */
108 struct nand_ecclayout {
109 	__u32 eccbytes;
110 	__u32 eccpos[MTD_MAX_ECCPOS_ENTRIES_LARGE];
111 	__u32 oobavail;
112 	struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
113 };
114 
115 struct module;	/* only needed for owner field in mtd_info */
116 
117 struct mtd_info {
118 	u_char type;
119 	uint32_t flags;
120 	uint64_t size;	 // Total size of the MTD
121 
122 	/* "Major" erase size for the device. Naïve users may take this
123 	 * to be the only erase size available, or may use the more detailed
124 	 * information below if they desire
125 	 */
126 	uint32_t erasesize;
127 	/* Minimal writable flash unit size. In case of NOR flash it is 1 (even
128 	 * though individual bits can be cleared), in case of NAND flash it is
129 	 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
130 	 * it is of ECC block size, etc. It is illegal to have writesize = 0.
131 	 * Any driver registering a struct mtd_info must ensure a writesize of
132 	 * 1 or larger.
133 	 */
134 	uint32_t writesize;
135 
136 	/*
137 	 * Size of the write buffer used by the MTD. MTD devices having a write
138 	 * buffer can write multiple writesize chunks at a time. E.g. while
139 	 * writing 4 * writesize bytes to a device with 2 * writesize bytes
140 	 * buffer the MTD driver can (but doesn't have to) do 2 writesize
141 	 * operations, but not 4. Currently, all NANDs have writebufsize
142 	 * equivalent to writesize (NAND page size). Some NOR flashes do have
143 	 * writebufsize greater than writesize.
144 	 */
145 	uint32_t writebufsize;
146 
147 	uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
148 	uint32_t oobavail;  // Available OOB bytes per block
149 
150 	/*
151 	 * If erasesize is a power of 2 then the shift is stored in
152 	 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
153 	 */
154 	unsigned int erasesize_shift;
155 	unsigned int writesize_shift;
156 	/* Masks based on erasesize_shift and writesize_shift */
157 	unsigned int erasesize_mask;
158 	unsigned int writesize_mask;
159 
160 	/*
161 	 * read ops return -EUCLEAN if max number of bitflips corrected on any
162 	 * one region comprising an ecc step equals or exceeds this value.
163 	 * Settable by driver, else defaults to ecc_strength.  User can override
164 	 * in sysfs.  N.B. The meaning of the -EUCLEAN return code has changed;
165 	 * see Documentation/ABI/testing/sysfs-class-mtd for more detail.
166 	 */
167 	unsigned int bitflip_threshold;
168 
169 	// Kernel-only stuff starts here.
170 	const char *name;
171 	int index;
172 
173 	/* ECC layout structure pointer - read only! */
174 	struct nand_ecclayout *ecclayout;
175 
176 	/* the ecc step size. */
177 	unsigned int ecc_step_size;
178 
179 	/* max number of correctible bit errors per ecc step */
180 	unsigned int ecc_strength;
181 
182 	/* Data for variable erase regions. If numeraseregions is zero,
183 	 * it means that the whole device has erasesize as given above.
184 	 */
185 	int numeraseregions;
186 	struct mtd_erase_region_info *eraseregions;
187 
188 	/*
189 	 * Do not call via these pointers, use corresponding mtd_*()
190 	 * wrappers instead.
191 	 */
192 	int (*_erase) (struct mtd_info *mtd, struct erase_info *instr);
193 	int (*_point) (struct mtd_info *mtd, loff_t from, size_t len,
194 		       size_t *retlen, void **virt, resource_size_t *phys);
195 	int (*_unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
196 	unsigned long (*_get_unmapped_area) (struct mtd_info *mtd,
197 					     unsigned long len,
198 					     unsigned long offset,
199 					     unsigned long flags);
200 	int (*_read) (struct mtd_info *mtd, loff_t from, size_t len,
201 		      size_t *retlen, u_char *buf);
202 	int (*_write) (struct mtd_info *mtd, loff_t to, size_t len,
203 		       size_t *retlen, const u_char *buf);
204 	int (*_panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
205 			     size_t *retlen, const u_char *buf);
206 	int (*_read_oob) (struct mtd_info *mtd, loff_t from,
207 			  struct mtd_oob_ops *ops);
208 	int (*_write_oob) (struct mtd_info *mtd, loff_t to,
209 			   struct mtd_oob_ops *ops);
210 	int (*_get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
211 				    size_t len);
212 	int (*_read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
213 				    size_t len, size_t *retlen, u_char *buf);
214 	int (*_get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
215 				    size_t len);
216 	int (*_read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
217 				    size_t len, size_t *retlen, u_char *buf);
218 	int (*_write_user_prot_reg) (struct mtd_info *mtd, loff_t to,
219 				     size_t len, size_t *retlen, u_char *buf);
220 	int (*_lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
221 				    size_t len);
222 	int (*_writev) (struct mtd_info *mtd, const struct kvec *vecs,
223 			unsigned long count, loff_t to, size_t *retlen);
224 	void (*_sync) (struct mtd_info *mtd);
225 	int (*_lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
226 	int (*_unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
227 	int (*_is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
228 	int (*_block_isbad) (struct mtd_info *mtd, loff_t ofs);
229 	int (*_block_markbad) (struct mtd_info *mtd, loff_t ofs);
230 	int (*_suspend) (struct mtd_info *mtd);
231 	void (*_resume) (struct mtd_info *mtd);
232 	/*
233 	 * If the driver is something smart, like UBI, it may need to maintain
234 	 * its own reference counting. The below functions are only for driver.
235 	 */
236 	int (*_get_device) (struct mtd_info *mtd);
237 	void (*_put_device) (struct mtd_info *mtd);
238 
239 	/* Backing device capabilities for this device
240 	 * - provides mmap capabilities
241 	 */
242 	struct backing_dev_info *backing_dev_info;
243 
244 	struct notifier_block reboot_notifier;  /* default mode before reboot */
245 
246 	/* ECC status information */
247 	struct mtd_ecc_stats ecc_stats;
248 	/* Subpage shift (NAND) */
249 	int subpage_sft;
250 
251 	void *priv;
252 
253 	struct module *owner;
254 	struct device dev;
255 	int usecount;
256 };
257 
258 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr);
259 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
260 	      void **virt, resource_size_t *phys);
261 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
262 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
263 				    unsigned long offset, unsigned long flags);
264 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
265 	     u_char *buf);
266 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
267 	      const u_char *buf);
268 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
269 		    const u_char *buf);
270 
271 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops);
272 
273 static inline int mtd_write_oob(struct mtd_info *mtd, loff_t to,
274 				struct mtd_oob_ops *ops)
275 {
276 	ops->retlen = ops->oobretlen = 0;
277 	if (!mtd->_write_oob)
278 		return -EOPNOTSUPP;
279 	if (!(mtd->flags & MTD_WRITEABLE))
280 		return -EROFS;
281 	return mtd->_write_oob(mtd, to, ops);
282 }
283 
284 int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
285 			   size_t len);
286 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
287 			   size_t *retlen, u_char *buf);
288 int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
289 			   size_t len);
290 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
291 			   size_t *retlen, u_char *buf);
292 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
293 			    size_t *retlen, u_char *buf);
294 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len);
295 
296 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
297 	       unsigned long count, loff_t to, size_t *retlen);
298 
299 static inline void mtd_sync(struct mtd_info *mtd)
300 {
301 	if (mtd->_sync)
302 		mtd->_sync(mtd);
303 }
304 
305 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
306 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
307 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
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_can_have_bb(const struct mtd_info *mtd)
358 {
359 	return !!mtd->_block_isbad;
360 }
361 
362 	/* Kernel-side ioctl definitions */
363 
364 struct mtd_partition;
365 struct mtd_part_parser_data;
366 
367 extern int mtd_device_parse_register(struct mtd_info *mtd,
368 				     const char * const *part_probe_types,
369 				     struct mtd_part_parser_data *parser_data,
370 				     const struct mtd_partition *defparts,
371 				     int defnr_parts);
372 #define mtd_device_register(master, parts, nr_parts)	\
373 	mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
374 extern int mtd_device_unregister(struct mtd_info *master);
375 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
376 extern int __get_mtd_device(struct mtd_info *mtd);
377 extern void __put_mtd_device(struct mtd_info *mtd);
378 extern struct mtd_info *get_mtd_device_nm(const char *name);
379 extern void put_mtd_device(struct mtd_info *mtd);
380 
381 
382 struct mtd_notifier {
383 	void (*add)(struct mtd_info *mtd);
384 	void (*remove)(struct mtd_info *mtd);
385 	struct list_head list;
386 };
387 
388 
389 extern void register_mtd_user (struct mtd_notifier *new);
390 extern int unregister_mtd_user (struct mtd_notifier *old);
391 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
392 
393 void mtd_erase_callback(struct erase_info *instr);
394 
395 static inline int mtd_is_bitflip(int err) {
396 	return err == -EUCLEAN;
397 }
398 
399 static inline int mtd_is_eccerr(int err) {
400 	return err == -EBADMSG;
401 }
402 
403 static inline int mtd_is_bitflip_or_eccerr(int err) {
404 	return mtd_is_bitflip(err) || mtd_is_eccerr(err);
405 }
406 
407 #endif /* __MTD_MTD_H__ */
408