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