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/module.h>
25 #include <linux/uio.h>
26 #include <linux/notifier.h>
27 #include <linux/device.h>
28
29 #include <mtd/mtd-abi.h>
30
31 #include <asm/div64.h>
32
33 #define MTD_CHAR_MAJOR 90
34 #define MTD_BLOCK_MAJOR 31
35
36 #define MTD_ERASE_PENDING 0x01
37 #define MTD_ERASING 0x02
38 #define MTD_ERASE_SUSPEND 0x04
39 #define MTD_ERASE_DONE 0x08
40 #define MTD_ERASE_FAILED 0x10
41
42 #define MTD_FAIL_ADDR_UNKNOWN -1LL
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 or was not
46 specific to any particular block. */
47 struct erase_info {
48 struct mtd_info *mtd;
49 uint64_t addr;
50 uint64_t len;
51 uint64_t fail_addr;
52 u_long time;
53 u_long retries;
54 unsigned dev;
55 unsigned cell;
56 void (*callback) (struct erase_info *self);
57 u_long priv;
58 u_char state;
59 struct erase_info *next;
60 };
61
62 struct mtd_erase_region_info {
63 uint64_t offset; /* At which this region starts, from the beginning of the MTD */
64 uint32_t erasesize; /* For this region */
65 uint32_t numblocks; /* Number of blocks of erasesize in this region */
66 unsigned long *lockmap; /* If keeping bitmap of locks */
67 };
68
69 /*
70 * oob operation modes
71 *
72 * MTD_OOB_PLACE: oob data are placed at the given offset
73 * MTD_OOB_AUTO: oob data are automatically placed at the free areas
74 * which are defined by the ecclayout
75 * MTD_OOB_RAW: mode to read oob and data without doing ECC checking
76 */
77 typedef enum {
78 MTD_OOB_PLACE,
79 MTD_OOB_AUTO,
80 MTD_OOB_RAW,
81 } mtd_oob_mode_t;
82
83 /**
84 * struct mtd_oob_ops - oob operation operands
85 * @mode: operation mode
86 *
87 * @len: number of data bytes to write/read
88 *
89 * @retlen: number of data bytes written/read
90 *
91 * @ooblen: number of oob bytes to write/read
92 * @oobretlen: number of oob bytes written/read
93 * @ooboffs: offset of oob data in the oob area (only relevant when
94 * mode = MTD_OOB_PLACE)
95 * @datbuf: data buffer - if NULL only oob data are read/written
96 * @oobbuf: oob data buffer
97 *
98 * Note, it is allowed to read more than one OOB area at one go, but not write.
99 * The interface assumes that the OOB write requests program only one page's
100 * OOB area.
101 */
102 struct mtd_oob_ops {
103 mtd_oob_mode_t mode;
104 size_t len;
105 size_t retlen;
106 size_t ooblen;
107 size_t oobretlen;
108 uint32_t ooboffs;
109 uint8_t *datbuf;
110 uint8_t *oobbuf;
111 };
112
113 #define MTD_MAX_OOBFREE_ENTRIES_LARGE 32
114 #define MTD_MAX_ECCPOS_ENTRIES_LARGE 448
115 /*
116 * Internal ECC layout control structure. For historical reasons, there is a
117 * similar, smaller struct nand_ecclayout_user (in mtd-abi.h) that is retained
118 * for export to user-space via the ECCGETLAYOUT ioctl.
119 * nand_ecclayout should be expandable in the future simply by the above macros.
120 */
121 struct nand_ecclayout {
122 __u32 eccbytes;
123 __u32 eccpos[MTD_MAX_ECCPOS_ENTRIES_LARGE];
124 __u32 oobavail;
125 struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
126 };
127
128 struct mtd_info {
129 u_char type;
130 uint32_t flags;
131 uint64_t size; // Total size of the MTD
132
133 /* "Major" erase size for the device. Naïve users may take this
134 * to be the only erase size available, or may use the more detailed
135 * information below if they desire
136 */
137 uint32_t erasesize;
138 /* Minimal writable flash unit size. In case of NOR flash it is 1 (even
139 * though individual bits can be cleared), in case of NAND flash it is
140 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
141 * it is of ECC block size, etc. It is illegal to have writesize = 0.
142 * Any driver registering a struct mtd_info must ensure a writesize of
143 * 1 or larger.
144 */
145 uint32_t writesize;
146
147 /*
148 * Size of the write buffer used by the MTD. MTD devices having a write
149 * buffer can write multiple writesize chunks at a time. E.g. while
150 * writing 4 * writesize bytes to a device with 2 * writesize bytes
151 * buffer the MTD driver can (but doesn't have to) do 2 writesize
152 * operations, but not 4. Currently, all NANDs have writebufsize
153 * equivalent to writesize (NAND page size). Some NOR flashes do have
154 * writebufsize greater than writesize.
155 */
156 uint32_t writebufsize;
157
158 uint32_t oobsize; // Amount of OOB data per block (e.g. 16)
159 uint32_t oobavail; // Available OOB bytes per block
160
161 /*
162 * If erasesize is a power of 2 then the shift is stored in
163 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
164 */
165 unsigned int erasesize_shift;
166 unsigned int writesize_shift;
167 /* Masks based on erasesize_shift and writesize_shift */
168 unsigned int erasesize_mask;
169 unsigned int writesize_mask;
170
171 // Kernel-only stuff starts here.
172 const char *name;
173 int index;
174
175 /* ecc layout structure pointer - read only ! */
176 struct nand_ecclayout *ecclayout;
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 * Erase is an asynchronous operation. Device drivers are supposed
186 * to call instr->callback() whenever the operation completes, even
187 * if it completes with a failure.
188 * Callers are supposed to pass a callback function and wait for it
189 * to be called before writing to the block.
190 */
191 int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
192
193 /* This stuff for eXecute-In-Place */
194 /* phys is optional and may be set to NULL */
195 int (*point) (struct mtd_info *mtd, loff_t from, size_t len,
196 size_t *retlen, void **virt, resource_size_t *phys);
197
198 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
199 void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
200
201 /* Allow NOMMU mmap() to directly map the device (if not NULL)
202 * - return the address to which the offset maps
203 * - return -ENOSYS to indicate refusal to do the mapping
204 */
205 unsigned long (*get_unmapped_area) (struct mtd_info *mtd,
206 unsigned long len,
207 unsigned long offset,
208 unsigned long flags);
209
210 /* Backing device capabilities for this device
211 * - provides mmap capabilities
212 */
213 struct backing_dev_info *backing_dev_info;
214
215
216 int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
217 int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
218
219 /* In blackbox flight recorder like scenarios we want to make successful
220 writes in interrupt context. panic_write() is only intended to be
221 called when its known the kernel is about to panic and we need the
222 write to succeed. Since the kernel is not going to be running for much
223 longer, this function can break locks and delay to ensure the write
224 succeeds (but not sleep). */
225
226 int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
227
228 int (*read_oob) (struct mtd_info *mtd, loff_t from,
229 struct mtd_oob_ops *ops);
230 int (*write_oob) (struct mtd_info *mtd, loff_t to,
231 struct mtd_oob_ops *ops);
232
233 /*
234 * Methods to access the protection register area, present in some
235 * flash devices. The user data is one time programmable but the
236 * factory data is read only.
237 */
238 int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
239 int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
240 int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
241 int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
242 int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
243 int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
244
245 /* kvec-based read/write methods.
246 NB: The 'count' parameter is the number of _vectors_, each of
247 which contains an (ofs, len) tuple.
248 */
249 int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
250
251 /* Sync */
252 void (*sync) (struct mtd_info *mtd);
253
254 /* Chip-supported device locking */
255 int (*lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
256 int (*unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
257 int (*is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
258
259 /* Power Management functions */
260 int (*suspend) (struct mtd_info *mtd);
261 void (*resume) (struct mtd_info *mtd);
262
263 /* Bad block management functions */
264 int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
265 int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
266
267 struct notifier_block reboot_notifier; /* default mode before reboot */
268
269 /* ECC status information */
270 struct mtd_ecc_stats ecc_stats;
271 /* Subpage shift (NAND) */
272 int subpage_sft;
273
274 void *priv;
275
276 struct module *owner;
277 struct device dev;
278 int usecount;
279
280 /* If the driver is something smart, like UBI, it may need to maintain
281 * its own reference counting. The below functions are only for driver.
282 * The driver may register its callbacks. These callbacks are not
283 * supposed to be called by MTD users */
284 int (*get_device) (struct mtd_info *mtd);
285 void (*put_device) (struct mtd_info *mtd);
286 };
287
dev_to_mtd(struct device * dev)288 static inline struct mtd_info *dev_to_mtd(struct device *dev)
289 {
290 return dev ? dev_get_drvdata(dev) : NULL;
291 }
292
mtd_div_by_eb(uint64_t sz,struct mtd_info * mtd)293 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
294 {
295 if (mtd->erasesize_shift)
296 return sz >> mtd->erasesize_shift;
297 do_div(sz, mtd->erasesize);
298 return sz;
299 }
300
mtd_mod_by_eb(uint64_t sz,struct mtd_info * mtd)301 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
302 {
303 if (mtd->erasesize_shift)
304 return sz & mtd->erasesize_mask;
305 return do_div(sz, mtd->erasesize);
306 }
307
mtd_div_by_ws(uint64_t sz,struct mtd_info * mtd)308 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
309 {
310 if (mtd->writesize_shift)
311 return sz >> mtd->writesize_shift;
312 do_div(sz, mtd->writesize);
313 return sz;
314 }
315
mtd_mod_by_ws(uint64_t sz,struct mtd_info * mtd)316 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
317 {
318 if (mtd->writesize_shift)
319 return sz & mtd->writesize_mask;
320 return do_div(sz, mtd->writesize);
321 }
322
323 /* Kernel-side ioctl definitions */
324
325 extern int add_mtd_device(struct mtd_info *mtd);
326 extern int del_mtd_device (struct mtd_info *mtd);
327
328 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
329 extern int __get_mtd_device(struct mtd_info *mtd);
330 extern void __put_mtd_device(struct mtd_info *mtd);
331 extern struct mtd_info *get_mtd_device_nm(const char *name);
332 extern void put_mtd_device(struct mtd_info *mtd);
333
334
335 struct mtd_notifier {
336 void (*add)(struct mtd_info *mtd);
337 void (*remove)(struct mtd_info *mtd);
338 struct list_head list;
339 };
340
341
342 extern void register_mtd_user (struct mtd_notifier *new);
343 extern int unregister_mtd_user (struct mtd_notifier *old);
344
345 int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
346 unsigned long count, loff_t to, size_t *retlen);
347
348 int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
349 unsigned long count, loff_t from, size_t *retlen);
350
351 #ifdef CONFIG_MTD_PARTITIONS
352 void mtd_erase_callback(struct erase_info *instr);
353 #else
mtd_erase_callback(struct erase_info * instr)354 static inline void mtd_erase_callback(struct erase_info *instr)
355 {
356 if (instr->callback)
357 instr->callback(instr);
358 }
359 #endif
360
361 /*
362 * Debugging macro and defines
363 */
364 #define MTD_DEBUG_LEVEL0 (0) /* Quiet */
365 #define MTD_DEBUG_LEVEL1 (1) /* Audible */
366 #define MTD_DEBUG_LEVEL2 (2) /* Loud */
367 #define MTD_DEBUG_LEVEL3 (3) /* Noisy */
368
369 #ifdef CONFIG_MTD_DEBUG
370 #define DEBUG(n, args...) \
371 do { \
372 if (n <= CONFIG_MTD_DEBUG_VERBOSE) \
373 printk(KERN_INFO args); \
374 } while(0)
375 #else /* CONFIG_MTD_DEBUG */
376 #define DEBUG(n, args...) \
377 do { \
378 if (0) \
379 printk(KERN_INFO args); \
380 } while(0)
381
382 #endif /* CONFIG_MTD_DEBUG */
383
384 #endif /* __MTD_MTD_H__ */
385