xref: /linux/include/uapi/mtd/mtd-abi.h (revision 3d0fe49454652117522f60bfbefb978ba0e5300b)
1 /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2 /*
3  * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
18  *
19  */
20 
21 #ifndef __MTD_ABI_H__
22 #define __MTD_ABI_H__
23 
24 #include <linux/types.h>
25 
26 struct erase_info_user {
27 	__u32 start;
28 	__u32 length;
29 };
30 
31 struct erase_info_user64 {
32 	__u64 start;
33 	__u64 length;
34 };
35 
36 struct mtd_oob_buf {
37 	__u32 start;
38 	__u32 length;
39 	unsigned char __user *ptr;
40 };
41 
42 struct mtd_oob_buf64 {
43 	__u64 start;
44 	__u32 pad;
45 	__u32 length;
46 	__u64 usr_ptr;
47 };
48 
49 /**
50  * MTD operation modes
51  *
52  * @MTD_OPS_PLACE_OOB:	OOB data are placed at the given offset (default)
53  * @MTD_OPS_AUTO_OOB:	OOB data are automatically placed at the free areas
54  *			which are defined by the internal ecclayout
55  * @MTD_OPS_RAW:	data are transferred as-is, with no error correction;
56  *			this mode implies %MTD_OPS_PLACE_OOB
57  *
58  * These modes can be passed to ioctl(MEMWRITE) and ioctl(MEMREAD); they are
59  * also used internally. See notes on "MTD file modes" for discussion on
60  * %MTD_OPS_RAW vs. %MTD_FILE_MODE_RAW.
61  */
62 enum {
63 	MTD_OPS_PLACE_OOB = 0,
64 	MTD_OPS_AUTO_OOB = 1,
65 	MTD_OPS_RAW = 2,
66 };
67 
68 /**
69  * struct mtd_write_req - data structure for requesting a write operation
70  *
71  * @start:	start address
72  * @len:	length of data buffer (only lower 32 bits are used)
73  * @ooblen:	length of OOB buffer (only lower 32 bits are used)
74  * @usr_data:	user-provided data buffer
75  * @usr_oob:	user-provided OOB buffer
76  * @mode:	MTD mode (see "MTD operation modes")
77  * @padding:	reserved, must be set to 0
78  *
79  * This structure supports ioctl(MEMWRITE) operations, allowing data and/or OOB
80  * writes in various modes. To write to OOB-only, set @usr_data == NULL, and to
81  * write data-only, set @usr_oob == NULL. However, setting both @usr_data and
82  * @usr_oob to NULL is not allowed.
83  */
84 struct mtd_write_req {
85 	__u64 start;
86 	__u64 len;
87 	__u64 ooblen;
88 	__u64 usr_data;
89 	__u64 usr_oob;
90 	__u8 mode;
91 	__u8 padding[7];
92 };
93 
94 /**
95  * struct mtd_read_req_ecc_stats - ECC statistics for a read operation
96  *
97  * @uncorrectable_errors: the number of uncorrectable errors that happened
98  *			  during the read operation
99  * @corrected_bitflips: the number of bitflips corrected during the read
100  *			operation
101  * @max_bitflips: the maximum number of bitflips detected in any single ECC
102  *		  step for the data read during the operation; this information
103  *		  can be used to decide whether the data stored in a specific
104  *		  region of the MTD device should be moved somewhere else to
105  *		  avoid data loss.
106  */
107 struct mtd_read_req_ecc_stats {
108 	__u32 uncorrectable_errors;
109 	__u32 corrected_bitflips;
110 	__u32 max_bitflips;
111 };
112 
113 /**
114  * struct mtd_read_req - data structure for requesting a read operation
115  *
116  * @start:	start address
117  * @len:	length of data buffer (only lower 32 bits are used)
118  * @ooblen:	length of OOB buffer (only lower 32 bits are used)
119  * @usr_data:	user-provided data buffer
120  * @usr_oob:	user-provided OOB buffer
121  * @mode:	MTD mode (see "MTD operation modes")
122  * @padding:	reserved, must be set to 0
123  * @ecc_stats:	ECC statistics for the read operation
124  *
125  * This structure supports ioctl(MEMREAD) operations, allowing data and/or OOB
126  * reads in various modes. To read from OOB-only, set @usr_data == NULL, and to
127  * read data-only, set @usr_oob == NULL. However, setting both @usr_data and
128  * @usr_oob to NULL is not allowed.
129  */
130 struct mtd_read_req {
131 	__u64 start;
132 	__u64 len;
133 	__u64 ooblen;
134 	__u64 usr_data;
135 	__u64 usr_oob;
136 	__u8 mode;
137 	__u8 padding[7];
138 	struct mtd_read_req_ecc_stats ecc_stats;
139 };
140 
141 #define MTD_ABSENT		0
142 #define MTD_RAM			1
143 #define MTD_ROM			2
144 #define MTD_NORFLASH		3
145 #define MTD_NANDFLASH		4	/* SLC NAND */
146 #define MTD_DATAFLASH		6
147 #define MTD_UBIVOLUME		7
148 #define MTD_MLCNANDFLASH	8	/* MLC NAND (including TLC) */
149 
150 #define MTD_WRITEABLE		0x400	/* Device is writeable */
151 #define MTD_BIT_WRITEABLE	0x800	/* Single bits can be flipped */
152 #define MTD_NO_ERASE		0x1000	/* No erase necessary */
153 #define MTD_POWERUP_LOCK	0x2000	/* Always locked after reset */
154 #define MTD_SLC_ON_MLC_EMULATION 0x4000	/* Emulate SLC behavior on MLC NANDs */
155 
156 /* Some common devices / combinations of capabilities */
157 #define MTD_CAP_ROM		0
158 #define MTD_CAP_RAM		(MTD_WRITEABLE | MTD_BIT_WRITEABLE | MTD_NO_ERASE)
159 #define MTD_CAP_NORFLASH	(MTD_WRITEABLE | MTD_BIT_WRITEABLE)
160 #define MTD_CAP_NANDFLASH	(MTD_WRITEABLE)
161 #define MTD_CAP_NVRAM		(MTD_WRITEABLE | MTD_BIT_WRITEABLE | MTD_NO_ERASE)
162 
163 /* Obsolete ECC byte placement modes (used with obsolete MEMGETOOBSEL) */
164 #define MTD_NANDECC_OFF		0	/* Switch off ECC (Not recommended) */
165 #define MTD_NANDECC_PLACE	1	/* Use the given placement in the structure (YAFFS1 legacy mode) */
166 #define MTD_NANDECC_AUTOPLACE	2	/* Use the default placement scheme */
167 #define MTD_NANDECC_PLACEONLY	3	/* Use the given placement in the structure (Do not store ecc result on read) */
168 #define MTD_NANDECC_AUTOPL_USR 	4	/* Use the given autoplacement scheme rather than using the default */
169 
170 /* OTP mode selection */
171 #define MTD_OTP_OFF		0
172 #define MTD_OTP_FACTORY		1
173 #define MTD_OTP_USER		2
174 
175 struct mtd_info_user {
176 	__u8 type;
177 	__u32 flags;
178 	__u32 size;	/* Total size of the MTD */
179 	__u32 erasesize;
180 	__u32 writesize;
181 	__u32 oobsize;	/* Amount of OOB data per block (e.g. 16) */
182 	__u64 padding;	/* Old obsolete field; do not use */
183 };
184 
185 struct region_info_user {
186 	__u32 offset;		/* At which this region starts,
187 				 * from the beginning of the MTD */
188 	__u32 erasesize;	/* For this region */
189 	__u32 numblocks;	/* Number of blocks in this region */
190 	__u32 regionindex;
191 };
192 
193 struct otp_info {
194 	__u32 start;
195 	__u32 length;
196 	__u32 locked;
197 };
198 
199 /*
200  * Note, the following ioctl existed in the past and was removed:
201  * #define MEMSETOOBSEL           _IOW('M', 9, struct nand_oobinfo)
202  * Try to avoid adding a new ioctl with the same ioctl number.
203  */
204 
205 /* Get basic MTD characteristics info (better to use sysfs) */
206 #define MEMGETINFO		_IOR('M', 1, struct mtd_info_user)
207 /* Erase segment of MTD */
208 #define MEMERASE		_IOW('M', 2, struct erase_info_user)
209 /* Write out-of-band data from MTD */
210 #define MEMWRITEOOB		_IOWR('M', 3, struct mtd_oob_buf)
211 /* Read out-of-band data from MTD */
212 #define MEMREADOOB		_IOWR('M', 4, struct mtd_oob_buf)
213 /* Lock a chip (for MTD that supports it) */
214 #define MEMLOCK			_IOW('M', 5, struct erase_info_user)
215 /* Unlock a chip (for MTD that supports it) */
216 #define MEMUNLOCK		_IOW('M', 6, struct erase_info_user)
217 /* Get the number of different erase regions */
218 #define MEMGETREGIONCOUNT	_IOR('M', 7, int)
219 /* Get information about the erase region for a specific index */
220 #define MEMGETREGIONINFO	_IOWR('M', 8, struct region_info_user)
221 /* Get info about OOB modes (e.g., RAW, PLACE, AUTO) - legacy interface */
222 #define MEMGETOOBSEL		_IOR('M', 10, struct nand_oobinfo)
223 /* Check if an eraseblock is bad */
224 #define MEMGETBADBLOCK		_IOW('M', 11, __kernel_loff_t)
225 /* Mark an eraseblock as bad */
226 #define MEMSETBADBLOCK		_IOW('M', 12, __kernel_loff_t)
227 /* Set OTP (One-Time Programmable) mode (factory vs. user) */
228 #define OTPSELECT		_IOR('M', 13, int)
229 /* Get number of OTP (One-Time Programmable) regions */
230 #define OTPGETREGIONCOUNT	_IOW('M', 14, int)
231 /* Get all OTP (One-Time Programmable) info about MTD */
232 #define OTPGETREGIONINFO	_IOW('M', 15, struct otp_info)
233 /* Lock a given range of user data (must be in mode %MTD_FILE_MODE_OTP_USER) */
234 #define OTPLOCK			_IOR('M', 16, struct otp_info)
235 /* Get ECC layout (deprecated) */
236 #define ECCGETLAYOUT		_IOR('M', 17, struct nand_ecclayout_user)
237 /* Get statistics about corrected/uncorrected errors */
238 #define ECCGETSTATS		_IOR('M', 18, struct mtd_ecc_stats)
239 /* Set MTD mode on a per-file-descriptor basis (see "MTD file modes") */
240 #define MTDFILEMODE		_IO('M', 19)
241 /* Erase segment of MTD (supports 64-bit address) */
242 #define MEMERASE64		_IOW('M', 20, struct erase_info_user64)
243 /* Write data to OOB (64-bit version) */
244 #define MEMWRITEOOB64		_IOWR('M', 21, struct mtd_oob_buf64)
245 /* Read data from OOB (64-bit version) */
246 #define MEMREADOOB64		_IOWR('M', 22, struct mtd_oob_buf64)
247 /* Check if chip is locked (for MTD that supports it) */
248 #define MEMISLOCKED		_IOR('M', 23, struct erase_info_user)
249 /*
250  * Most generic write interface; can write in-band and/or out-of-band in various
251  * modes (see "struct mtd_write_req"). This ioctl is not supported for flashes
252  * without OOB, e.g., NOR flash.
253  */
254 #define MEMWRITE		_IOWR('M', 24, struct mtd_write_req)
255 /* Erase a given range of user data (must be in mode %MTD_FILE_MODE_OTP_USER) */
256 #define OTPERASE		_IOW('M', 25, struct otp_info)
257 /*
258  * Most generic read interface; can read in-band and/or out-of-band in various
259  * modes (see "struct mtd_read_req"). This ioctl is not supported for flashes
260  * without OOB, e.g., NOR flash.
261  */
262 #define MEMREAD			_IOWR('M', 26, struct mtd_read_req)
263 
264 /*
265  * Obsolete legacy interface. Keep it in order not to break userspace
266  * interfaces
267  */
268 struct nand_oobinfo {
269 	__u32 useecc;
270 	__u32 eccbytes;
271 	__u32 oobfree[8][2];
272 	__u32 eccpos[32];
273 };
274 
275 struct nand_oobfree {
276 	__u32 offset;
277 	__u32 length;
278 };
279 
280 #define MTD_MAX_OOBFREE_ENTRIES	8
281 #define MTD_MAX_ECCPOS_ENTRIES	64
282 /*
283  * OBSOLETE: ECC layout control structure. Exported to user-space via ioctl
284  * ECCGETLAYOUT for backwards compatbility and should not be mistaken as a
285  * complete set of ECC information. The ioctl truncates the larger internal
286  * structure to retain binary compatibility with the static declaration of the
287  * ioctl. Note that the "MTD_MAX_..._ENTRIES" macros represent the max size of
288  * the user struct, not the MAX size of the internal OOB layout representation.
289  */
290 struct nand_ecclayout_user {
291 	__u32 eccbytes;
292 	__u32 eccpos[MTD_MAX_ECCPOS_ENTRIES];
293 	__u32 oobavail;
294 	struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES];
295 };
296 
297 /**
298  * struct mtd_ecc_stats - error correction stats
299  *
300  * @corrected:	number of corrected bits
301  * @failed:	number of uncorrectable errors
302  * @badblocks:	number of bad blocks in this partition
303  * @bbtblocks:	number of blocks reserved for bad block tables
304  */
305 struct mtd_ecc_stats {
306 	__u32 corrected;
307 	__u32 failed;
308 	__u32 badblocks;
309 	__u32 bbtblocks;
310 };
311 
312 /*
313  * MTD file modes - for read/write access to MTD
314  *
315  * @MTD_FILE_MODE_NORMAL:	OTP disabled, ECC enabled
316  * @MTD_FILE_MODE_OTP_FACTORY:	OTP enabled in factory mode
317  * @MTD_FILE_MODE_OTP_USER:	OTP enabled in user mode
318  * @MTD_FILE_MODE_RAW:		OTP disabled, ECC disabled
319  *
320  * These modes can be set via ioctl(MTDFILEMODE). The mode will be retained
321  * separately for each open file descriptor.
322  *
323  * Note: %MTD_FILE_MODE_RAW provides the same functionality as %MTD_OPS_RAW -
324  * raw access to the flash, without error correction or autoplacement schemes.
325  * Wherever possible, the MTD_OPS_* mode will override the MTD_FILE_MODE_* mode
326  * (e.g., when using ioctl(MEMWRITE) or ioctl(MEMREAD)), but in some cases, the
327  * MTD_FILE_MODE is used out of necessity (e.g., `write()',
328  * ioctl(MEMWRITEOOB64)).
329  */
330 enum mtd_file_modes {
331 	MTD_FILE_MODE_NORMAL = MTD_OTP_OFF,
332 	MTD_FILE_MODE_OTP_FACTORY = MTD_OTP_FACTORY,
333 	MTD_FILE_MODE_OTP_USER = MTD_OTP_USER,
334 	MTD_FILE_MODE_RAW,
335 };
336 
337 static inline int mtd_type_is_nand_user(const struct mtd_info_user *mtd)
338 {
339 	return mtd->type == MTD_NANDFLASH || mtd->type == MTD_MLCNANDFLASH;
340 }
341 
342 #endif /* __MTD_ABI_H__ */
343