xref: /openbmc/u-boot/lib/fdtdec.c (revision 8a00061e)
1 /*
2  * Copyright (c) 2011 The Chromium OS Authors.
3  * See file CREDITS for list of people who contributed to this
4  * project.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation; either version 2 of
9  * the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
19  * MA 02111-1307 USA
20  */
21 
22 #include <common.h>
23 #include <serial.h>
24 #include <libfdt.h>
25 #include <fdtdec.h>
26 
27 #include <asm/gpio.h>
28 
29 DECLARE_GLOBAL_DATA_PTR;
30 
31 /*
32  * Here are the type we know about. One day we might allow drivers to
33  * register. For now we just put them here. The COMPAT macro allows us to
34  * turn this into a sparse list later, and keeps the ID with the name.
35  */
36 #define COMPAT(id, name) name
37 static const char * const compat_names[COMPAT_COUNT] = {
38 	COMPAT(UNKNOWN, "<none>"),
39 	COMPAT(NVIDIA_TEGRA20_USB, "nvidia,tegra20-ehci"),
40 	COMPAT(NVIDIA_TEGRA114_I2C, "nvidia,tegra114-i2c"),
41 	COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"),
42 	COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"),
43 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
44 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
45 	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
46 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
47 	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
48 	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
49 	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
50 	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
51 	COMPAT(NVIDIA_TEGRA20_SFLASH, "nvidia,tegra20-sflash"),
52 	COMPAT(NVIDIA_TEGRA20_SLINK, "nvidia,tegra20-slink"),
53 	COMPAT(NVIDIA_TEGRA114_SPI, "nvidia,tegra114-spi"),
54 	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
55 	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
56 	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
57 	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
58 	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
59 	COMPAT(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"),
60 	COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
61 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
62 	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
63 	COMPAT(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
64 	COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
65 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
66 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
67 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
68 	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
69 };
70 
71 const char *fdtdec_get_compatible(enum fdt_compat_id id)
72 {
73 	/* We allow reading of the 'unknown' ID for testing purposes */
74 	assert(id >= 0 && id < COMPAT_COUNT);
75 	return compat_names[id];
76 }
77 
78 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
79 		const char *prop_name, fdt_size_t *sizep)
80 {
81 	const fdt_addr_t *cell;
82 	int len;
83 
84 	debug("%s: %s: ", __func__, prop_name);
85 	cell = fdt_getprop(blob, node, prop_name, &len);
86 	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
87 		     len == sizeof(fdt_addr_t) * 2)) {
88 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
89 		if (sizep) {
90 			const fdt_size_t *size;
91 
92 			size = (fdt_size_t *)((char *)cell +
93 					sizeof(fdt_addr_t));
94 			*sizep = fdt_size_to_cpu(*size);
95 			debug("addr=%p, size=%p\n", (void *)addr,
96 			      (void *)*sizep);
97 		} else {
98 			debug("%p\n", (void *)addr);
99 		}
100 		return addr;
101 	}
102 	debug("(not found)\n");
103 	return FDT_ADDR_T_NONE;
104 }
105 
106 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
107 		const char *prop_name)
108 {
109 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
110 }
111 
112 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
113 		s32 default_val)
114 {
115 	const s32 *cell;
116 	int len;
117 
118 	debug("%s: %s: ", __func__, prop_name);
119 	cell = fdt_getprop(blob, node, prop_name, &len);
120 	if (cell && len >= sizeof(s32)) {
121 		s32 val = fdt32_to_cpu(cell[0]);
122 
123 		debug("%#x (%d)\n", val, val);
124 		return val;
125 	}
126 	debug("(not found)\n");
127 	return default_val;
128 }
129 
130 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
131 		uint64_t default_val)
132 {
133 	const uint64_t *cell64;
134 	int length;
135 
136 	cell64 = fdt_getprop(blob, node, prop_name, &length);
137 	if (!cell64 || length < sizeof(*cell64))
138 		return default_val;
139 
140 	return fdt64_to_cpu(*cell64);
141 }
142 
143 int fdtdec_get_is_enabled(const void *blob, int node)
144 {
145 	const char *cell;
146 
147 	/*
148 	 * It should say "okay", so only allow that. Some fdts use "ok" but
149 	 * this is a bug. Please fix your device tree source file. See here
150 	 * for discussion:
151 	 *
152 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
153 	 */
154 	cell = fdt_getprop(blob, node, "status", NULL);
155 	if (cell)
156 		return 0 == strcmp(cell, "okay");
157 	return 1;
158 }
159 
160 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
161 {
162 	enum fdt_compat_id id;
163 
164 	/* Search our drivers */
165 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
166 		if (0 == fdt_node_check_compatible(blob, node,
167 				compat_names[id]))
168 			return id;
169 	return COMPAT_UNKNOWN;
170 }
171 
172 int fdtdec_next_compatible(const void *blob, int node,
173 		enum fdt_compat_id id)
174 {
175 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
176 }
177 
178 int fdtdec_next_compatible_subnode(const void *blob, int node,
179 		enum fdt_compat_id id, int *depthp)
180 {
181 	do {
182 		node = fdt_next_node(blob, node, depthp);
183 	} while (*depthp > 1);
184 
185 	/* If this is a direct subnode, and compatible, return it */
186 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
187 						blob, node, compat_names[id]))
188 		return node;
189 
190 	return -FDT_ERR_NOTFOUND;
191 }
192 
193 int fdtdec_next_alias(const void *blob, const char *name,
194 		enum fdt_compat_id id, int *upto)
195 {
196 #define MAX_STR_LEN 20
197 	char str[MAX_STR_LEN + 20];
198 	int node, err;
199 
200 	/* snprintf() is not available */
201 	assert(strlen(name) < MAX_STR_LEN);
202 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
203 	node = fdt_path_offset(blob, str);
204 	if (node < 0)
205 		return node;
206 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
207 	if (err < 0)
208 		return err;
209 	if (err)
210 		return -FDT_ERR_NOTFOUND;
211 	(*upto)++;
212 	return node;
213 }
214 
215 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
216 			enum fdt_compat_id id, int *node_list, int maxcount)
217 {
218 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
219 
220 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
221 }
222 
223 /* TODO: Can we tighten this code up a little? */
224 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
225 			enum fdt_compat_id id, int *node_list, int maxcount)
226 {
227 	int name_len = strlen(name);
228 	int nodes[maxcount];
229 	int num_found = 0;
230 	int offset, node;
231 	int alias_node;
232 	int count;
233 	int i, j;
234 
235 	/* find the alias node if present */
236 	alias_node = fdt_path_offset(blob, "/aliases");
237 
238 	/*
239 	 * start with nothing, and we can assume that the root node can't
240 	 * match
241 	 */
242 	memset(nodes, '\0', sizeof(nodes));
243 
244 	/* First find all the compatible nodes */
245 	for (node = count = 0; node >= 0 && count < maxcount;) {
246 		node = fdtdec_next_compatible(blob, node, id);
247 		if (node >= 0)
248 			nodes[count++] = node;
249 	}
250 	if (node >= 0)
251 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
252 		       __func__, name);
253 
254 	/* Now find all the aliases */
255 	for (offset = fdt_first_property_offset(blob, alias_node);
256 			offset > 0;
257 			offset = fdt_next_property_offset(blob, offset)) {
258 		const struct fdt_property *prop;
259 		const char *path;
260 		int number;
261 		int found;
262 
263 		node = 0;
264 		prop = fdt_get_property_by_offset(blob, offset, NULL);
265 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
266 		if (prop->len && 0 == strncmp(path, name, name_len))
267 			node = fdt_path_offset(blob, prop->data);
268 		if (node <= 0)
269 			continue;
270 
271 		/* Get the alias number */
272 		number = simple_strtoul(path + name_len, NULL, 10);
273 		if (number < 0 || number >= maxcount) {
274 			debug("%s: warning: alias '%s' is out of range\n",
275 			       __func__, path);
276 			continue;
277 		}
278 
279 		/* Make sure the node we found is actually in our list! */
280 		found = -1;
281 		for (j = 0; j < count; j++)
282 			if (nodes[j] == node) {
283 				found = j;
284 				break;
285 			}
286 
287 		if (found == -1) {
288 			debug("%s: warning: alias '%s' points to a node "
289 				"'%s' that is missing or is not compatible "
290 				" with '%s'\n", __func__, path,
291 				fdt_get_name(blob, node, NULL),
292 			       compat_names[id]);
293 			continue;
294 		}
295 
296 		/*
297 		 * Add this node to our list in the right place, and mark
298 		 * it as done.
299 		 */
300 		if (fdtdec_get_is_enabled(blob, node)) {
301 			if (node_list[number]) {
302 				debug("%s: warning: alias '%s' requires that "
303 				      "a node be placed in the list in a "
304 				      "position which is already filled by "
305 				      "node '%s'\n", __func__, path,
306 				      fdt_get_name(blob, node, NULL));
307 				continue;
308 			}
309 			node_list[number] = node;
310 			if (number >= num_found)
311 				num_found = number + 1;
312 		}
313 		nodes[found] = 0;
314 	}
315 
316 	/* Add any nodes not mentioned by an alias */
317 	for (i = j = 0; i < maxcount; i++) {
318 		if (!node_list[i]) {
319 			for (; j < maxcount; j++)
320 				if (nodes[j] &&
321 					fdtdec_get_is_enabled(blob, nodes[j]))
322 					break;
323 
324 			/* Have we run out of nodes to add? */
325 			if (j == maxcount)
326 				break;
327 
328 			assert(!node_list[i]);
329 			node_list[i] = nodes[j++];
330 			if (i >= num_found)
331 				num_found = i + 1;
332 		}
333 	}
334 
335 	return num_found;
336 }
337 
338 int fdtdec_check_fdt(void)
339 {
340 	/*
341 	 * We must have an FDT, but we cannot panic() yet since the console
342 	 * is not ready. So for now, just assert(). Boards which need an early
343 	 * FDT (prior to console ready) will need to make their own
344 	 * arrangements and do their own checks.
345 	 */
346 	assert(!fdtdec_prepare_fdt());
347 	return 0;
348 }
349 
350 /*
351  * This function is a little odd in that it accesses global data. At some
352  * point if the architecture board.c files merge this will make more sense.
353  * Even now, it is common code.
354  */
355 int fdtdec_prepare_fdt(void)
356 {
357 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
358 	    fdt_check_header(gd->fdt_blob)) {
359 		printf("No valid FDT found - please append one to U-Boot "
360 			"binary, use u-boot-dtb.bin or define "
361 			"CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
362 		return -1;
363 	}
364 	return 0;
365 }
366 
367 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
368 {
369 	const u32 *phandle;
370 	int lookup;
371 
372 	debug("%s: %s\n", __func__, prop_name);
373 	phandle = fdt_getprop(blob, node, prop_name, NULL);
374 	if (!phandle)
375 		return -FDT_ERR_NOTFOUND;
376 
377 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
378 	return lookup;
379 }
380 
381 /**
382  * Look up a property in a node and check that it has a minimum length.
383  *
384  * @param blob		FDT blob
385  * @param node		node to examine
386  * @param prop_name	name of property to find
387  * @param min_len	minimum property length in bytes
388  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
389 			found, or -FDT_ERR_BADLAYOUT if not enough data
390  * @return pointer to cell, which is only valid if err == 0
391  */
392 static const void *get_prop_check_min_len(const void *blob, int node,
393 		const char *prop_name, int min_len, int *err)
394 {
395 	const void *cell;
396 	int len;
397 
398 	debug("%s: %s\n", __func__, prop_name);
399 	cell = fdt_getprop(blob, node, prop_name, &len);
400 	if (!cell)
401 		*err = -FDT_ERR_NOTFOUND;
402 	else if (len < min_len)
403 		*err = -FDT_ERR_BADLAYOUT;
404 	else
405 		*err = 0;
406 	return cell;
407 }
408 
409 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
410 		u32 *array, int count)
411 {
412 	const u32 *cell;
413 	int i, err = 0;
414 
415 	debug("%s: %s\n", __func__, prop_name);
416 	cell = get_prop_check_min_len(blob, node, prop_name,
417 				      sizeof(u32) * count, &err);
418 	if (!err) {
419 		for (i = 0; i < count; i++)
420 			array[i] = fdt32_to_cpu(cell[i]);
421 	}
422 	return err;
423 }
424 
425 const u32 *fdtdec_locate_array(const void *blob, int node,
426 			       const char *prop_name, int count)
427 {
428 	const u32 *cell;
429 	int err;
430 
431 	cell = get_prop_check_min_len(blob, node, prop_name,
432 				      sizeof(u32) * count, &err);
433 	return err ? NULL : cell;
434 }
435 
436 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
437 {
438 	const s32 *cell;
439 	int len;
440 
441 	debug("%s: %s\n", __func__, prop_name);
442 	cell = fdt_getprop(blob, node, prop_name, &len);
443 	return cell != NULL;
444 }
445 
446 /**
447  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
448  * terminating item.
449  *
450  * @param blob		FDT blob to use
451  * @param node		Node to look at
452  * @param prop_name	Node property name
453  * @param gpio		Array of gpio elements to fill from FDT. This will be
454  *			untouched if either 0 or an error is returned
455  * @param max_count	Maximum number of elements allowed
456  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
457  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
458  */
459 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
460 		struct fdt_gpio_state *gpio, int max_count)
461 {
462 	const struct fdt_property *prop;
463 	const u32 *cell;
464 	const char *name;
465 	int len, i;
466 
467 	debug("%s: %s\n", __func__, prop_name);
468 	assert(max_count > 0);
469 	prop = fdt_get_property(blob, node, prop_name, &len);
470 	if (!prop) {
471 		debug("%s: property '%s' missing\n", __func__, prop_name);
472 		return -FDT_ERR_NOTFOUND;
473 	}
474 
475 	/* We will use the name to tag the GPIO */
476 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
477 	cell = (u32 *)prop->data;
478 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
479 	if (len > max_count) {
480 		debug(" %s: too many GPIOs / cells for "
481 			"property '%s'\n", __func__, prop_name);
482 		return -FDT_ERR_BADLAYOUT;
483 	}
484 
485 	/* Read out the GPIO data from the cells */
486 	for (i = 0; i < len; i++, cell += 3) {
487 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
488 		gpio[i].flags = fdt32_to_cpu(cell[2]);
489 		gpio[i].name = name;
490 	}
491 
492 	return len;
493 }
494 
495 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
496 		struct fdt_gpio_state *gpio)
497 {
498 	int err;
499 
500 	debug("%s: %s\n", __func__, prop_name);
501 	gpio->gpio = FDT_GPIO_NONE;
502 	gpio->name = NULL;
503 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
504 	return err == 1 ? 0 : err;
505 }
506 
507 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
508 {
509 	int val;
510 
511 	if (!fdt_gpio_isvalid(gpio))
512 		return -1;
513 
514 	val = gpio_get_value(gpio->gpio);
515 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
516 }
517 
518 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
519 {
520 	if (!fdt_gpio_isvalid(gpio))
521 		return -1;
522 
523 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
524 	return gpio_set_value(gpio->gpio, val);
525 }
526 
527 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
528 {
529 	/*
530 	 * Return success if there is no GPIO defined. This is used for
531 	 * optional GPIOs)
532 	 */
533 	if (!fdt_gpio_isvalid(gpio))
534 		return 0;
535 
536 	if (gpio_request(gpio->gpio, gpio->name))
537 		return -1;
538 	return 0;
539 }
540 
541 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
542 		u8 *array, int count)
543 {
544 	const u8 *cell;
545 	int err;
546 
547 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
548 	if (!err)
549 		memcpy(array, cell, count);
550 	return err;
551 }
552 
553 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
554 			     const char *prop_name, int count)
555 {
556 	const u8 *cell;
557 	int err;
558 
559 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
560 	if (err)
561 		return NULL;
562 	return cell;
563 }
564 
565 int fdtdec_get_config_int(const void *blob, const char *prop_name,
566 		int default_val)
567 {
568 	int config_node;
569 
570 	debug("%s: %s\n", __func__, prop_name);
571 	config_node = fdt_path_offset(blob, "/config");
572 	if (config_node < 0)
573 		return default_val;
574 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
575 }
576 
577 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
578 {
579 	int config_node;
580 	const void *prop;
581 
582 	debug("%s: %s\n", __func__, prop_name);
583 	config_node = fdt_path_offset(blob, "/config");
584 	if (config_node < 0)
585 		return 0;
586 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
587 
588 	return prop != NULL;
589 }
590 
591 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
592 {
593 	const char *nodep;
594 	int nodeoffset;
595 	int len;
596 
597 	debug("%s: %s\n", __func__, prop_name);
598 	nodeoffset = fdt_path_offset(blob, "/config");
599 	if (nodeoffset < 0)
600 		return NULL;
601 
602 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
603 	if (!nodep)
604 		return NULL;
605 
606 	return (char *)nodep;
607 }
608 
609 int fdtdec_decode_region(const void *blob, int node,
610 		const char *prop_name, void **ptrp, size_t *size)
611 {
612 	const fdt_addr_t *cell;
613 	int len;
614 
615 	debug("%s: %s\n", __func__, prop_name);
616 	cell = fdt_getprop(blob, node, prop_name, &len);
617 	if (!cell || (len != sizeof(fdt_addr_t) * 2))
618 		return -1;
619 
620 	*ptrp = (void *)fdt_addr_to_cpu(*cell);
621 	*size = fdt_size_to_cpu(cell[1]);
622 	debug("%s: size=%zx\n", __func__, *size);
623 	return 0;
624 }
625