1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2017 Free Electrons
4 *
5 * Authors:
6 * Boris Brezillon <boris.brezillon@free-electrons.com>
7 * Peter Pan <peterpandong@micron.com>
8 */
9
10 #define pr_fmt(fmt) "nand: " fmt
11
12 #include <linux/module.h>
13 #include <linux/mtd/nand.h>
14
15 /**
16 * nanddev_isbad() - Check if a block is bad
17 * @nand: NAND device
18 * @pos: position pointing to the block we want to check
19 *
20 * Return: true if the block is bad, false otherwise.
21 */
nanddev_isbad(struct nand_device * nand,const struct nand_pos * pos)22 bool nanddev_isbad(struct nand_device *nand, const struct nand_pos *pos)
23 {
24 if (mtd_check_expert_analysis_mode())
25 return false;
26
27 if (nanddev_bbt_is_initialized(nand)) {
28 unsigned int entry;
29 int status;
30
31 entry = nanddev_bbt_pos_to_entry(nand, pos);
32 status = nanddev_bbt_get_block_status(nand, entry);
33 /* Lazy block status retrieval */
34 if (status == NAND_BBT_BLOCK_STATUS_UNKNOWN) {
35 if (nand->ops->isbad(nand, pos))
36 status = NAND_BBT_BLOCK_FACTORY_BAD;
37 else
38 status = NAND_BBT_BLOCK_GOOD;
39
40 nanddev_bbt_set_block_status(nand, entry, status);
41 }
42
43 if (status == NAND_BBT_BLOCK_WORN ||
44 status == NAND_BBT_BLOCK_FACTORY_BAD)
45 return true;
46
47 return false;
48 }
49
50 return nand->ops->isbad(nand, pos);
51 }
52 EXPORT_SYMBOL_GPL(nanddev_isbad);
53
54 /**
55 * nanddev_markbad() - Mark a block as bad
56 * @nand: NAND device
57 * @pos: position of the block to mark bad
58 *
59 * Mark a block bad. This function is updating the BBT if available and
60 * calls the low-level markbad hook (nand->ops->markbad()).
61 *
62 * Return: 0 in case of success, a negative error code otherwise.
63 */
nanddev_markbad(struct nand_device * nand,const struct nand_pos * pos)64 int nanddev_markbad(struct nand_device *nand, const struct nand_pos *pos)
65 {
66 struct mtd_info *mtd = nanddev_to_mtd(nand);
67 unsigned int entry;
68 int ret = 0;
69
70 if (nanddev_isbad(nand, pos))
71 return 0;
72
73 ret = nand->ops->markbad(nand, pos);
74 if (ret)
75 pr_warn("failed to write BBM to block @%llx (err = %d)\n",
76 nanddev_pos_to_offs(nand, pos), ret);
77
78 if (!nanddev_bbt_is_initialized(nand))
79 goto out;
80
81 entry = nanddev_bbt_pos_to_entry(nand, pos);
82 ret = nanddev_bbt_set_block_status(nand, entry, NAND_BBT_BLOCK_WORN);
83 if (ret)
84 goto out;
85
86 ret = nanddev_bbt_update(nand);
87
88 out:
89 if (!ret)
90 mtd->ecc_stats.badblocks++;
91
92 return ret;
93 }
94 EXPORT_SYMBOL_GPL(nanddev_markbad);
95
96 /**
97 * nanddev_isreserved() - Check whether an eraseblock is reserved or not
98 * @nand: NAND device
99 * @pos: NAND position to test
100 *
101 * Checks whether the eraseblock pointed by @pos is reserved or not.
102 *
103 * Return: true if the eraseblock is reserved, false otherwise.
104 */
nanddev_isreserved(struct nand_device * nand,const struct nand_pos * pos)105 bool nanddev_isreserved(struct nand_device *nand, const struct nand_pos *pos)
106 {
107 unsigned int entry;
108 int status;
109
110 if (!nanddev_bbt_is_initialized(nand))
111 return false;
112
113 /* Return info from the table */
114 entry = nanddev_bbt_pos_to_entry(nand, pos);
115 status = nanddev_bbt_get_block_status(nand, entry);
116 return status == NAND_BBT_BLOCK_RESERVED;
117 }
118 EXPORT_SYMBOL_GPL(nanddev_isreserved);
119
120 /**
121 * nanddev_erase() - Erase a NAND portion
122 * @nand: NAND device
123 * @pos: position of the block to erase
124 *
125 * Erases the block if it's not bad.
126 *
127 * Return: 0 in case of success, a negative error code otherwise.
128 */
nanddev_erase(struct nand_device * nand,const struct nand_pos * pos)129 static int nanddev_erase(struct nand_device *nand, const struct nand_pos *pos)
130 {
131 if (nanddev_isbad(nand, pos) || nanddev_isreserved(nand, pos)) {
132 pr_warn("attempt to erase a bad/reserved block @%llx\n",
133 nanddev_pos_to_offs(nand, pos));
134 return -EIO;
135 }
136
137 return nand->ops->erase(nand, pos);
138 }
139
140 /**
141 * nanddev_mtd_erase() - Generic mtd->_erase() implementation for NAND devices
142 * @mtd: MTD device
143 * @einfo: erase request
144 *
145 * This is a simple mtd->_erase() implementation iterating over all blocks
146 * concerned by @einfo and calling nand->ops->erase() on each of them.
147 *
148 * Note that mtd->_erase should not be directly assigned to this helper,
149 * because there's no locking here. NAND specialized layers should instead
150 * implement there own wrapper around nanddev_mtd_erase() taking the
151 * appropriate lock before calling nanddev_mtd_erase().
152 *
153 * Return: 0 in case of success, a negative error code otherwise.
154 */
nanddev_mtd_erase(struct mtd_info * mtd,struct erase_info * einfo)155 int nanddev_mtd_erase(struct mtd_info *mtd, struct erase_info *einfo)
156 {
157 struct nand_device *nand = mtd_to_nanddev(mtd);
158 struct nand_pos pos, last;
159 int ret;
160
161 nanddev_offs_to_pos(nand, einfo->addr, &pos);
162 nanddev_offs_to_pos(nand, einfo->addr + einfo->len - 1, &last);
163 while (nanddev_pos_cmp(&pos, &last) <= 0) {
164 ret = nanddev_erase(nand, &pos);
165 if (ret) {
166 einfo->fail_addr = nanddev_pos_to_offs(nand, &pos);
167
168 return ret;
169 }
170
171 nanddev_pos_next_eraseblock(nand, &pos);
172 }
173
174 return 0;
175 }
176 EXPORT_SYMBOL_GPL(nanddev_mtd_erase);
177
178 /**
179 * nanddev_mtd_max_bad_blocks() - Get the maximum number of bad eraseblock on
180 * a specific region of the NAND device
181 * @mtd: MTD device
182 * @offs: offset of the NAND region
183 * @len: length of the NAND region
184 *
185 * Default implementation for mtd->_max_bad_blocks(). Only works if
186 * nand->memorg.max_bad_eraseblocks_per_lun is > 0.
187 *
188 * Return: a positive number encoding the maximum number of eraseblocks on a
189 * portion of memory, a negative error code otherwise.
190 */
nanddev_mtd_max_bad_blocks(struct mtd_info * mtd,loff_t offs,size_t len)191 int nanddev_mtd_max_bad_blocks(struct mtd_info *mtd, loff_t offs, size_t len)
192 {
193 struct nand_device *nand = mtd_to_nanddev(mtd);
194 struct nand_pos pos, end;
195 unsigned int max_bb = 0;
196
197 if (!nand->memorg.max_bad_eraseblocks_per_lun)
198 return -ENOTSUPP;
199
200 nanddev_offs_to_pos(nand, offs, &pos);
201 nanddev_offs_to_pos(nand, offs + len, &end);
202
203 for (nanddev_offs_to_pos(nand, offs, &pos);
204 nanddev_pos_cmp(&pos, &end) < 0;
205 nanddev_pos_next_lun(nand, &pos))
206 max_bb += nand->memorg.max_bad_eraseblocks_per_lun;
207
208 return max_bb;
209 }
210 EXPORT_SYMBOL_GPL(nanddev_mtd_max_bad_blocks);
211
212 /**
213 * nanddev_get_ecc_engine() - Find and get a suitable ECC engine
214 * @nand: NAND device
215 */
nanddev_get_ecc_engine(struct nand_device * nand)216 static int nanddev_get_ecc_engine(struct nand_device *nand)
217 {
218 int engine_type;
219
220 /* Read the user desires in terms of ECC engine/configuration */
221 of_get_nand_ecc_user_config(nand);
222
223 engine_type = nand->ecc.user_conf.engine_type;
224 if (engine_type == NAND_ECC_ENGINE_TYPE_INVALID)
225 engine_type = nand->ecc.defaults.engine_type;
226
227 switch (engine_type) {
228 case NAND_ECC_ENGINE_TYPE_NONE:
229 return 0;
230 case NAND_ECC_ENGINE_TYPE_SOFT:
231 nand->ecc.engine = nand_ecc_get_sw_engine(nand);
232 break;
233 case NAND_ECC_ENGINE_TYPE_ON_DIE:
234 nand->ecc.engine = nand_ecc_get_on_die_hw_engine(nand);
235 break;
236 case NAND_ECC_ENGINE_TYPE_ON_HOST:
237 nand->ecc.engine = nand_ecc_get_on_host_hw_engine(nand);
238 if (PTR_ERR(nand->ecc.engine) == -EPROBE_DEFER)
239 return -EPROBE_DEFER;
240 break;
241 default:
242 pr_err("Missing ECC engine type\n");
243 }
244
245 if (!nand->ecc.engine)
246 return -EINVAL;
247
248 return 0;
249 }
250
251 /**
252 * nanddev_put_ecc_engine() - Dettach and put the in-use ECC engine
253 * @nand: NAND device
254 */
nanddev_put_ecc_engine(struct nand_device * nand)255 static int nanddev_put_ecc_engine(struct nand_device *nand)
256 {
257 switch (nand->ecc.ctx.conf.engine_type) {
258 case NAND_ECC_ENGINE_TYPE_ON_HOST:
259 nand_ecc_put_on_host_hw_engine(nand);
260 break;
261 case NAND_ECC_ENGINE_TYPE_NONE:
262 case NAND_ECC_ENGINE_TYPE_SOFT:
263 case NAND_ECC_ENGINE_TYPE_ON_DIE:
264 default:
265 break;
266 }
267
268 return 0;
269 }
270
271 /**
272 * nanddev_find_ecc_configuration() - Find a suitable ECC configuration
273 * @nand: NAND device
274 */
nanddev_find_ecc_configuration(struct nand_device * nand)275 static int nanddev_find_ecc_configuration(struct nand_device *nand)
276 {
277 int ret;
278
279 if (!nand->ecc.engine)
280 return -ENOTSUPP;
281
282 ret = nand_ecc_init_ctx(nand);
283 if (ret)
284 return ret;
285
286 if (!nand_ecc_is_strong_enough(nand))
287 pr_warn("WARNING: %s: the ECC used on your system is too weak compared to the one required by the NAND chip\n",
288 nand->mtd.name);
289
290 return 0;
291 }
292
293 /**
294 * nanddev_ecc_engine_init() - Initialize an ECC engine for the chip
295 * @nand: NAND device
296 */
nanddev_ecc_engine_init(struct nand_device * nand)297 int nanddev_ecc_engine_init(struct nand_device *nand)
298 {
299 int ret;
300
301 /* Look for the ECC engine to use */
302 ret = nanddev_get_ecc_engine(nand);
303 if (ret) {
304 if (ret != -EPROBE_DEFER)
305 pr_err("No ECC engine found\n");
306
307 return ret;
308 }
309
310 /* No ECC engine requested */
311 if (!nand->ecc.engine)
312 return 0;
313
314 /* Configure the engine: balance user input and chip requirements */
315 ret = nanddev_find_ecc_configuration(nand);
316 if (ret) {
317 pr_err("No suitable ECC configuration\n");
318 nanddev_put_ecc_engine(nand);
319
320 return ret;
321 }
322
323 return 0;
324 }
325 EXPORT_SYMBOL_GPL(nanddev_ecc_engine_init);
326
327 /**
328 * nanddev_ecc_engine_cleanup() - Cleanup ECC engine initializations
329 * @nand: NAND device
330 */
nanddev_ecc_engine_cleanup(struct nand_device * nand)331 void nanddev_ecc_engine_cleanup(struct nand_device *nand)
332 {
333 if (nand->ecc.engine)
334 nand_ecc_cleanup_ctx(nand);
335
336 nanddev_put_ecc_engine(nand);
337 }
338 EXPORT_SYMBOL_GPL(nanddev_ecc_engine_cleanup);
339
340 /**
341 * nanddev_init() - Initialize a NAND device
342 * @nand: NAND device
343 * @ops: NAND device operations
344 * @owner: NAND device owner
345 *
346 * Initializes a NAND device object. Consistency checks are done on @ops and
347 * @nand->memorg. Also takes care of initializing the BBT.
348 *
349 * Return: 0 in case of success, a negative error code otherwise.
350 */
nanddev_init(struct nand_device * nand,const struct nand_ops * ops,struct module * owner)351 int nanddev_init(struct nand_device *nand, const struct nand_ops *ops,
352 struct module *owner)
353 {
354 struct mtd_info *mtd = nanddev_to_mtd(nand);
355 struct nand_memory_organization *memorg = nanddev_get_memorg(nand);
356
357 if (!nand || !ops)
358 return -EINVAL;
359
360 if (!ops->erase || !ops->markbad || !ops->isbad)
361 return -EINVAL;
362
363 if (!memorg->bits_per_cell || !memorg->pagesize ||
364 !memorg->pages_per_eraseblock || !memorg->eraseblocks_per_lun ||
365 !memorg->planes_per_lun || !memorg->luns_per_target ||
366 !memorg->ntargets)
367 return -EINVAL;
368
369 nand->rowconv.eraseblock_addr_shift =
370 fls(memorg->pages_per_eraseblock - 1);
371 nand->rowconv.lun_addr_shift = fls(memorg->eraseblocks_per_lun - 1) +
372 nand->rowconv.eraseblock_addr_shift;
373
374 nand->ops = ops;
375
376 mtd->type = memorg->bits_per_cell == 1 ?
377 MTD_NANDFLASH : MTD_MLCNANDFLASH;
378 mtd->flags = MTD_CAP_NANDFLASH;
379 mtd->erasesize = memorg->pagesize * memorg->pages_per_eraseblock;
380 mtd->writesize = memorg->pagesize;
381 mtd->writebufsize = memorg->pagesize;
382 mtd->oobsize = memorg->oobsize;
383 mtd->size = nanddev_size(nand);
384 mtd->owner = owner;
385
386 return nanddev_bbt_init(nand);
387 }
388 EXPORT_SYMBOL_GPL(nanddev_init);
389
390 /**
391 * nanddev_cleanup() - Release resources allocated in nanddev_init()
392 * @nand: NAND device
393 *
394 * Basically undoes what has been done in nanddev_init().
395 */
nanddev_cleanup(struct nand_device * nand)396 void nanddev_cleanup(struct nand_device *nand)
397 {
398 if (nanddev_bbt_is_initialized(nand))
399 nanddev_bbt_cleanup(nand);
400 }
401 EXPORT_SYMBOL_GPL(nanddev_cleanup);
402
403 MODULE_DESCRIPTION("Generic NAND framework");
404 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
405 MODULE_LICENSE("GPL v2");
406