1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2014
4 * Heiko Schocher, DENX Software Engineering, hs@denx.de.
5 */
6 #include <common.h>
7 #include <env.h>
8 #include <log.h>
9 #include <malloc.h>
10 #include <dm/device.h>
11 #include <dm/uclass-internal.h>
12 #include <dm/uclass.h>
13 #include <linux/err.h>
14 #include <linux/mtd/mtd.h>
15 #include <linux/mtd/partitions.h>
16 #include <asm/global_data.h>
17 #include <mtd.h>
18
19 #define MTD_NAME_MAX_LEN 20
20
21 void board_mtdparts_default(const char **mtdids, const char **mtdparts);
22
get_mtdids(void)23 static const char *get_mtdids(void)
24 {
25 __maybe_unused const char *mtdparts = NULL;
26 const char *mtdids = env_get("mtdids");
27
28 if (mtdids)
29 return mtdids;
30
31 #if defined(CONFIG_SYS_MTDPARTS_RUNTIME)
32 board_mtdparts_default(&mtdids, &mtdparts);
33 #elif defined(MTDIDS_DEFAULT)
34 mtdids = MTDIDS_DEFAULT;
35 #elif defined(CONFIG_MTDIDS_DEFAULT)
36 mtdids = CONFIG_MTDIDS_DEFAULT;
37 #endif
38
39 if (mtdids)
40 env_set("mtdids", mtdids);
41
42 return mtdids;
43 }
44
45 /**
46 * mtd_search_alternate_name - Search an alternate name for @mtdname thanks to
47 * the mtdids legacy environment variable.
48 *
49 * The mtdids string is a list of comma-separated 'dev_id=mtd_id' tupples.
50 * Check if one of the mtd_id matches mtdname, in this case save dev_id in
51 * altname.
52 *
53 * @mtdname: Current MTD device name
54 * @altname: Alternate name to return
55 * @max_len: Length of the alternate name buffer
56 *
57 * @return 0 on success, an error otherwise.
58 */
mtd_search_alternate_name(const char * mtdname,char * altname,unsigned int max_len)59 int mtd_search_alternate_name(const char *mtdname, char *altname,
60 unsigned int max_len)
61 {
62 const char *mtdids, *equal, *comma, *dev_id, *mtd_id;
63 int dev_id_len, mtd_id_len;
64
65 mtdids = get_mtdids();
66 if (!mtdids)
67 return -EINVAL;
68
69 do {
70 /* Find the '=' sign */
71 dev_id = mtdids;
72 equal = strchr(dev_id, '=');
73 if (!equal)
74 break;
75 dev_id_len = equal - mtdids;
76 mtd_id = equal + 1;
77
78 /* Find the end of the tupple */
79 comma = strchr(mtdids, ',');
80 if (comma)
81 mtd_id_len = comma - mtd_id;
82 else
83 mtd_id_len = &mtdids[strlen(mtdids)] - mtd_id + 1;
84
85 if (!dev_id_len || !mtd_id_len)
86 return -EINVAL;
87
88 if (dev_id_len + 1 > max_len)
89 continue;
90
91 /* Compare the name we search with the current mtd_id */
92 if (!strncmp(mtdname, mtd_id, mtd_id_len)) {
93 strncpy(altname, dev_id, dev_id_len);
94 altname[dev_id_len] = 0;
95
96 return 0;
97 }
98
99 /* Go to the next tupple */
100 mtdids = comma + 1;
101 } while (comma);
102
103 return -EINVAL;
104 }
105
106 #if IS_ENABLED(CONFIG_DM_MTD)
mtd_probe_uclass_mtd_devs(void)107 static void mtd_probe_uclass_mtd_devs(void)
108 {
109 struct udevice *dev;
110
111 uclass_foreach_dev_probe(UCLASS_MTD, dev)
112 ;
113 }
114 #else
mtd_probe_uclass_mtd_devs(void)115 static void mtd_probe_uclass_mtd_devs(void) { }
116 #endif
117
118 #if IS_ENABLED(CONFIG_DM_SPI_FLASH) && IS_ENABLED(CONFIG_SPI_FLASH_MTD)
mtd_probe_uclass_spi_nor_devs(void)119 static void mtd_probe_uclass_spi_nor_devs(void)
120 {
121 struct udevice *dev;
122
123 uclass_foreach_dev_probe(UCLASS_SPI_FLASH, dev)
124 ;
125 }
126 #else
mtd_probe_uclass_spi_nor_devs(void)127 static void mtd_probe_uclass_spi_nor_devs(void) { }
128 #endif
129
130 #if defined(CONFIG_MTD_PARTITIONS)
131
132 #define MTDPARTS_MAXLEN 512
133
get_mtdparts(void)134 static const char *get_mtdparts(void)
135 {
136 __maybe_unused const char *mtdids = NULL;
137 static char tmp_parts[MTDPARTS_MAXLEN];
138 const char *mtdparts = NULL;
139
140 if (gd->flags & GD_FLG_ENV_READY)
141 mtdparts = env_get("mtdparts");
142 else if (env_get_f("mtdparts", tmp_parts, sizeof(tmp_parts)) != -1)
143 mtdparts = tmp_parts;
144
145 if (mtdparts)
146 return mtdparts;
147
148 #if defined(CONFIG_SYS_MTDPARTS_RUNTIME)
149 board_mtdparts_default(&mtdids, &mtdparts);
150 #elif defined(MTDPARTS_DEFAULT)
151 mtdparts = MTDPARTS_DEFAULT;
152 #elif defined(CONFIG_MTDPARTS_DEFAULT)
153 mtdparts = CONFIG_MTDPARTS_DEFAULT;
154 #endif
155
156 if (mtdparts)
157 env_set("mtdparts", mtdparts);
158
159 return mtdparts;
160 }
161
mtd_del_parts(struct mtd_info * mtd,bool quiet)162 static int mtd_del_parts(struct mtd_info *mtd, bool quiet)
163 {
164 int ret;
165
166 if (!mtd_has_partitions(mtd))
167 return 0;
168
169 /* do not delete partitions if they are in use. */
170 if (mtd_partitions_used(mtd)) {
171 if (!quiet)
172 printf("\"%s\" partitions still in use, can't delete them\n",
173 mtd->name);
174 return -EACCES;
175 }
176
177 ret = del_mtd_partitions(mtd);
178 if (ret)
179 return ret;
180
181 return 1;
182 }
183
184 static bool mtd_del_all_parts_failed;
185
mtd_del_all_parts(void)186 static void mtd_del_all_parts(void)
187 {
188 struct mtd_info *mtd;
189 int ret = 0;
190
191 mtd_del_all_parts_failed = false;
192
193 /*
194 * It is not safe to remove entries from the mtd_for_each_device loop
195 * as it uses idr indexes and the partitions removal is done in bulk
196 * (all partitions of one device at the same time), so break and
197 * iterate from start each time a new partition is found and deleted.
198 */
199 do {
200 mtd_for_each_device(mtd) {
201 ret = mtd_del_parts(mtd, false);
202 if (ret > 0)
203 break;
204 else if (ret < 0)
205 mtd_del_all_parts_failed = true;
206 }
207 } while (ret > 0);
208 }
209
parse_mtdparts(const char * mtdparts,const char * mtdids)210 static int parse_mtdparts(const char *mtdparts, const char *mtdids)
211 {
212 const char *mtdparts_next;
213 struct mtd_info *mtd;
214
215 /* Start the parsing by ignoring the extra 'mtdparts=' prefix, if any */
216 if (!strncmp(mtdparts, "mtdparts=", sizeof("mtdparts=") - 1))
217 mtdparts += 9;
218
219 /* For each MTD device in mtdparts */
220 for (; mtdparts[0] != '\0'; mtdparts = mtdparts_next) {
221 char mtd_name[MTD_NAME_MAX_LEN], *colon;
222 struct mtd_partition *parts;
223 unsigned int mtd_name_len;
224 int nparts, ret;
225
226 mtdparts_next = strchr(mtdparts, ';');
227 if (!mtdparts_next)
228 mtdparts_next = mtdparts + strlen(mtdparts);
229 else
230 mtdparts_next++;
231
232 colon = strchr(mtdparts, ':');
233 if (colon > mtdparts_next)
234 colon = NULL;
235
236 if (!colon) {
237 printf("Wrong mtdparts: %s\n", mtdparts);
238 return -EINVAL;
239 }
240
241 mtd_name_len = (unsigned int)(colon - mtdparts);
242 if (mtd_name_len + 1 > sizeof(mtd_name)) {
243 printf("MTD name too long: %s\n", mtdparts);
244 return -EINVAL;
245 }
246
247 strncpy(mtd_name, mtdparts, mtd_name_len);
248 mtd_name[mtd_name_len] = '\0';
249 /* Move the pointer forward (including the ':') */
250 mtdparts += mtd_name_len + 1;
251 mtd = get_mtd_device_nm(mtd_name);
252 if (IS_ERR_OR_NULL(mtd)) {
253 char linux_name[MTD_NAME_MAX_LEN];
254
255 /*
256 * The MTD device named "mtd_name" does not exist. Try
257 * to find a correspondance with an MTD device having
258 * the same type and number as defined in the mtdids.
259 */
260 debug("No device named %s\n", mtd_name);
261 ret = mtd_search_alternate_name(mtd_name, linux_name,
262 MTD_NAME_MAX_LEN);
263 if (!ret)
264 mtd = get_mtd_device_nm(linux_name);
265
266 /*
267 * If no device could be found, move the mtdparts
268 * pointer forward until the next set of partitions.
269 */
270 if (ret || IS_ERR_OR_NULL(mtd)) {
271 printf("Could not find a valid device for %s\n",
272 mtd_name);
273 mtdparts = mtdparts_next;
274 continue;
275 }
276 }
277
278 /*
279 * Call mtd_del_parts() again, even if it's already been called
280 * in mtd_del_all_parts(). We need to know if old partitions are
281 * still around (because they are still being used by someone),
282 * and if they are, we shouldn't create new partitions, so just
283 * skip this MTD device and try the next one.
284 */
285 ret = mtd_del_parts(mtd, true);
286 if (ret < 0)
287 continue;
288
289 /*
290 * Parse the MTD device partitions. It will update the mtdparts
291 * pointer, create an array of parts (that must be freed), and
292 * return the number of partition structures in the array.
293 */
294 ret = mtd_parse_partitions(mtd, &mtdparts, &parts, &nparts);
295 if (ret) {
296 printf("Could not parse device %s\n", mtd->name);
297 put_mtd_device(mtd);
298 return -EINVAL;
299 }
300
301 if (!nparts)
302 continue;
303
304 /* Create the new MTD partitions */
305 add_mtd_partitions(mtd, parts, nparts);
306
307 /* Free the structures allocated during the parsing */
308 mtd_free_parsed_partitions(parts, nparts);
309
310 put_mtd_device(mtd);
311 }
312
313 return 0;
314 }
315
mtd_probe_devices(void)316 int mtd_probe_devices(void)
317 {
318 static char *old_mtdparts;
319 static char *old_mtdids;
320 const char *mtdparts = get_mtdparts();
321 const char *mtdids = get_mtdids();
322 struct mtd_info *mtd;
323
324 mtd_probe_uclass_mtd_devs();
325 mtd_probe_uclass_spi_nor_devs();
326
327 /*
328 * Check if mtdparts/mtdids changed, if the MTD dev list was updated
329 * or if our previous attempt to delete existing partititions failed.
330 * In any of these cases we want to update the partitions, otherwise,
331 * everything is up-to-date and we can return 0 directly.
332 */
333 if ((!mtdparts && !old_mtdparts && !mtdids && !old_mtdids) ||
334 (mtdparts && old_mtdparts && mtdids && old_mtdids &&
335 !mtd_dev_list_updated() && !mtd_del_all_parts_failed &&
336 !strcmp(mtdparts, old_mtdparts) &&
337 !strcmp(mtdids, old_mtdids)))
338 return 0;
339
340 /* Update the local copy of mtdparts */
341 free(old_mtdparts);
342 free(old_mtdids);
343 old_mtdparts = strdup(mtdparts);
344 old_mtdids = strdup(mtdids);
345
346 /*
347 * Remove all old parts. Note that partition removal can fail in case
348 * one of the partition is still being used by an MTD user, so this
349 * does not guarantee that all old partitions are gone.
350 */
351 mtd_del_all_parts();
352
353 /*
354 * Call mtd_dev_list_updated() to clear updates generated by our own
355 * parts removal loop.
356 */
357 mtd_dev_list_updated();
358
359 /* If both mtdparts and mtdids are non-empty, parse */
360 if (mtdparts && mtdids) {
361 if (parse_mtdparts(mtdparts, mtdids) < 0)
362 printf("Failed parsing MTD partitions from mtdparts!\n");
363 }
364
365 /* Fallback to OF partitions */
366 mtd_for_each_device(mtd) {
367 if (list_empty(&mtd->partitions)) {
368 if (add_mtd_partitions_of(mtd) < 0)
369 printf("Failed parsing MTD %s OF partitions!\n",
370 mtd->name);
371 }
372 }
373
374 /*
375 * Call mtd_dev_list_updated() to clear updates generated by our own
376 * parts registration loop.
377 */
378 mtd_dev_list_updated();
379
380 return 0;
381 }
382 #else
mtd_probe_devices(void)383 int mtd_probe_devices(void)
384 {
385 mtd_probe_uclass_mtd_devs();
386 mtd_probe_uclass_spi_nor_devs();
387
388 return 0;
389 }
390 #endif /* defined(CONFIG_MTD_PARTITIONS) */
391