xref: /openbmc/u-boot/drivers/mtd/mtd_uboot.c (revision fd0bc623)
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 <dm/device.h>
8 #include <dm/uclass-internal.h>
9 #include <jffs2/jffs2.h> /* LEGACY */
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 
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  */
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_MTD)
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
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 
121 static const char *get_mtdparts(void)
122 {
123 	__maybe_unused const char *mtdids = NULL;
124 	static char tmp_parts[MTDPARTS_MAXLEN];
125 	static bool use_defaults = true;
126 	const char *mtdparts = NULL;
127 
128 	if (gd->flags & GD_FLG_ENV_READY)
129 		mtdparts = env_get("mtdparts");
130 	else if (env_get_f("mtdparts", tmp_parts, sizeof(tmp_parts)) != -1)
131 		mtdparts = tmp_parts;
132 
133 	if (mtdparts || !use_defaults)
134 		return mtdparts;
135 
136 #if defined(CONFIG_SYS_MTDPARTS_RUNTIME)
137 	board_mtdparts_default(&mtdids, &mtdparts);
138 #elif defined(MTDPARTS_DEFAULT)
139 	mtdparts = MTDPARTS_DEFAULT;
140 #elif defined(CONFIG_MTDPARTS_DEFAULT)
141 	mtdparts = CONFIG_MTDPARTS_DEFAULT;
142 #endif
143 
144 	if (mtdparts)
145 		env_set("mtdparts", mtdparts);
146 
147 	use_defaults = false;
148 
149 	return mtdparts;
150 }
151 
152 static int mtd_del_parts(struct mtd_info *mtd, bool quiet)
153 {
154 	int ret;
155 
156 	if (!mtd_has_partitions(mtd))
157 		return 0;
158 
159 	/* do not delete partitions if they are in use. */
160 	if (mtd_partitions_used(mtd)) {
161 		if (!quiet)
162 			printf("\"%s\" partitions still in use, can't delete them\n",
163 			       mtd->name);
164 		return -EACCES;
165 	}
166 
167 	ret = del_mtd_partitions(mtd);
168 	if (ret)
169 		return ret;
170 
171 	return 1;
172 }
173 
174 static bool mtd_del_all_parts_failed;
175 
176 static void mtd_del_all_parts(void)
177 {
178 	struct mtd_info *mtd;
179 	int ret = 0;
180 
181 	mtd_del_all_parts_failed = false;
182 
183 	/*
184 	 * It is not safe to remove entries from the mtd_for_each_device loop
185 	 * as it uses idr indexes and the partitions removal is done in bulk
186 	 * (all partitions of one device at the same time), so break and
187 	 * iterate from start each time a new partition is found and deleted.
188 	 */
189 	do {
190 		mtd_for_each_device(mtd) {
191 			ret = mtd_del_parts(mtd, false);
192 			if (ret > 0)
193 				break;
194 			else if (ret < 0)
195 				mtd_del_all_parts_failed = true;
196 		}
197 	} while (ret > 0);
198 }
199 
200 int mtd_probe_devices(void)
201 {
202 	static char *old_mtdparts;
203 	static char *old_mtdids;
204 	const char *mtdparts = get_mtdparts();
205 	const char *mtdids = get_mtdids();
206 	const char *mtdparts_next = mtdparts;
207 	struct mtd_info *mtd;
208 
209 	mtd_probe_uclass_mtd_devs();
210 
211 	/*
212 	 * Check if mtdparts/mtdids changed, if the MTD dev list was updated
213 	 * or if our previous attempt to delete existing partititions failed.
214 	 * In any of these cases we want to update the partitions, otherwise,
215 	 * everything is up-to-date and we can return 0 directly.
216 	 */
217 	if ((!mtdparts && !old_mtdparts && !mtdids && !old_mtdids) ||
218 	    (mtdparts && old_mtdparts && mtdids && old_mtdids &&
219 	     !mtd_dev_list_updated() && !mtd_del_all_parts_failed &&
220 	     !strcmp(mtdparts, old_mtdparts) &&
221 	     !strcmp(mtdids, old_mtdids)))
222 		return 0;
223 
224 	/* Update the local copy of mtdparts */
225 	free(old_mtdparts);
226 	free(old_mtdids);
227 	old_mtdparts = strdup(mtdparts);
228 	old_mtdids = strdup(mtdids);
229 
230 	/*
231 	 * Remove all old parts. Note that partition removal can fail in case
232 	 * one of the partition is still being used by an MTD user, so this
233 	 * does not guarantee that all old partitions are gone.
234 	 */
235 	mtd_del_all_parts();
236 
237 	/*
238 	 * Call mtd_dev_list_updated() to clear updates generated by our own
239 	 * parts removal loop.
240 	 */
241 	mtd_dev_list_updated();
242 
243 	/* If either mtdparts or mtdids is empty, then exit */
244 	if (!mtdparts || !mtdids)
245 		return 0;
246 
247 	/* Start the parsing by ignoring the extra 'mtdparts=' prefix, if any */
248 	if (!strncmp(mtdparts, "mtdparts=", sizeof("mtdparts=") - 1))
249 		mtdparts += 9;
250 
251 	/* For each MTD device in mtdparts */
252 	for (; mtdparts[0] != '\0'; mtdparts = mtdparts_next) {
253 		char mtd_name[MTD_NAME_MAX_LEN], *colon;
254 		struct mtd_partition *parts;
255 		unsigned int mtd_name_len;
256 		int nparts, ret;
257 
258 		mtdparts_next = strchr(mtdparts, ';');
259 		if (!mtdparts_next)
260 			mtdparts_next = mtdparts + strlen(mtdparts);
261 		else
262 			mtdparts_next++;
263 
264 		colon = strchr(mtdparts, ':');
265 		if (colon > mtdparts_next)
266 			colon = NULL;
267 
268 		if (!colon) {
269 			printf("Wrong mtdparts: %s\n", mtdparts);
270 			return -EINVAL;
271 		}
272 
273 		mtd_name_len = (unsigned int)(colon - mtdparts);
274 		if (mtd_name_len + 1 > sizeof(mtd_name)) {
275 			printf("MTD name too long: %s\n", mtdparts);
276 			return -EINVAL;
277 		}
278 
279 		strncpy(mtd_name, mtdparts, mtd_name_len);
280 		mtd_name[mtd_name_len] = '\0';
281 		/* Move the pointer forward (including the ':') */
282 		mtdparts += mtd_name_len + 1;
283 		mtd = get_mtd_device_nm(mtd_name);
284 		if (IS_ERR_OR_NULL(mtd)) {
285 			char linux_name[MTD_NAME_MAX_LEN];
286 
287 			/*
288 			 * The MTD device named "mtd_name" does not exist. Try
289 			 * to find a correspondance with an MTD device having
290 			 * the same type and number as defined in the mtdids.
291 			 */
292 			debug("No device named %s\n", mtd_name);
293 			ret = mtd_search_alternate_name(mtd_name, linux_name,
294 							MTD_NAME_MAX_LEN);
295 			if (!ret)
296 				mtd = get_mtd_device_nm(linux_name);
297 
298 			/*
299 			 * If no device could be found, move the mtdparts
300 			 * pointer forward until the next set of partitions.
301 			 */
302 			if (ret || IS_ERR_OR_NULL(mtd)) {
303 				printf("Could not find a valid device for %s\n",
304 				       mtd_name);
305 				mtdparts = mtdparts_next;
306 				continue;
307 			}
308 		}
309 
310 		/*
311 		 * Call mtd_del_parts() again, even if it's already been called
312 		 * in mtd_del_all_parts(). We need to know if old partitions are
313 		 * still around (because they are still being used by someone),
314 		 * and if they are, we shouldn't create new partitions, so just
315 		 * skip this MTD device and try the next one.
316 		 */
317 		ret = mtd_del_parts(mtd, true);
318 		if (ret < 0)
319 			continue;
320 
321 		/*
322 		 * Parse the MTD device partitions. It will update the mtdparts
323 		 * pointer, create an array of parts (that must be freed), and
324 		 * return the number of partition structures in the array.
325 		 */
326 		ret = mtd_parse_partitions(mtd, &mtdparts, &parts, &nparts);
327 		if (ret) {
328 			printf("Could not parse device %s\n", mtd->name);
329 			put_mtd_device(mtd);
330 			return -EINVAL;
331 		}
332 
333 		if (!nparts)
334 			continue;
335 
336 		/* Create the new MTD partitions */
337 		add_mtd_partitions(mtd, parts, nparts);
338 
339 		/* Free the structures allocated during the parsing */
340 		mtd_free_parsed_partitions(parts, nparts);
341 
342 		put_mtd_device(mtd);
343 	}
344 
345 	/*
346 	 * Call mtd_dev_list_updated() to clear updates generated by our own
347 	 * parts registration loop.
348 	 */
349 	mtd_dev_list_updated();
350 
351 	return 0;
352 }
353 #else
354 int mtd_probe_devices(void)
355 {
356 	mtd_probe_uclass_mtd_devs();
357 
358 	return 0;
359 }
360 #endif /* defined(CONFIG_MTD_PARTITIONS) */
361 
362 /* Legacy */
363 
364 static int get_part(const char *partname, int *idx, loff_t *off, loff_t *size,
365 		loff_t *maxsize, int devtype)
366 {
367 #ifdef CONFIG_CMD_MTDPARTS
368 	struct mtd_device *dev;
369 	struct part_info *part;
370 	u8 pnum;
371 	int ret;
372 
373 	ret = mtdparts_init();
374 	if (ret)
375 		return ret;
376 
377 	ret = find_dev_and_part(partname, &dev, &pnum, &part);
378 	if (ret)
379 		return ret;
380 
381 	if (dev->id->type != devtype) {
382 		printf("not same typ %d != %d\n", dev->id->type, devtype);
383 		return -1;
384 	}
385 
386 	*off = part->offset;
387 	*size = part->size;
388 	*maxsize = part->size;
389 	*idx = dev->id->num;
390 
391 	return 0;
392 #else
393 	puts("mtdparts support missing.\n");
394 	return -1;
395 #endif
396 }
397 
398 int mtd_arg_off(const char *arg, int *idx, loff_t *off, loff_t *size,
399 		loff_t *maxsize, int devtype, uint64_t chipsize)
400 {
401 	if (!str2off(arg, off))
402 		return get_part(arg, idx, off, size, maxsize, devtype);
403 
404 	if (*off >= chipsize) {
405 		puts("Offset exceeds device limit\n");
406 		return -1;
407 	}
408 
409 	*maxsize = chipsize - *off;
410 	*size = *maxsize;
411 	return 0;
412 }
413 
414 int mtd_arg_off_size(int argc, char *const argv[], int *idx, loff_t *off,
415 		     loff_t *size, loff_t *maxsize, int devtype,
416 		     uint64_t chipsize)
417 {
418 	int ret;
419 
420 	if (argc == 0) {
421 		*off = 0;
422 		*size = chipsize;
423 		*maxsize = *size;
424 		goto print;
425 	}
426 
427 	ret = mtd_arg_off(argv[0], idx, off, size, maxsize, devtype,
428 			  chipsize);
429 	if (ret)
430 		return ret;
431 
432 	if (argc == 1)
433 		goto print;
434 
435 	if (!str2off(argv[1], size)) {
436 		printf("'%s' is not a number\n", argv[1]);
437 		return -1;
438 	}
439 
440 	if (*size > *maxsize) {
441 		puts("Size exceeds partition or device limit\n");
442 		return -1;
443 	}
444 
445 print:
446 	printf("device %d ", *idx);
447 	if (*size == chipsize)
448 		puts("whole chip\n");
449 	else
450 		printf("offset 0x%llx, size 0x%llx\n",
451 		       (unsigned long long)*off, (unsigned long long)*size);
452 	return 0;
453 }
454