xref: /openbmc/u-boot/lib/fdtdec.c (revision 04735e9c5578dd4f3584be5454b9779e8e5c2af9)
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_TEGRA30_USB, "nvidia,tegra30-ehci"),
41 	COMPAT(NVIDIA_TEGRA114_USB, "nvidia,tegra114-ehci"),
42 	COMPAT(NVIDIA_TEGRA114_I2C, "nvidia,tegra114-i2c"),
43 	COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"),
44 	COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"),
45 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
46 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
47 	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
48 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
49 	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
50 	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
51 	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
52 	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
53 	COMPAT(NVIDIA_TEGRA20_SFLASH, "nvidia,tegra20-sflash"),
54 	COMPAT(NVIDIA_TEGRA20_SLINK, "nvidia,tegra20-slink"),
55 	COMPAT(NVIDIA_TEGRA114_SPI, "nvidia,tegra114-spi"),
56 	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
57 	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
58 	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
59 	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
60 	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
61 	COMPAT(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"),
62 	COMPAT(GOOGLE_CROS_EC, "google,cros-ec"),
63 	COMPAT(GOOGLE_CROS_EC_KEYB, "google,cros-ec-keyb"),
64 	COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
65 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
66 	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
67 	COMPAT(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
68 	COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
69 	COMPAT(SAMSUNG_EXYNOS5_DWMMC, "samsung,exynos5250-dwmmc"),
70 	COMPAT(SAMSUNG_EXYNOS_SERIAL, "samsung,exynos4210-uart"),
71 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
72 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
73 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
74 	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
75 	COMPAT(INFINEON_SLB9645_TPM, "infineon,slb9645-tpm"),
76 };
77 
78 const char *fdtdec_get_compatible(enum fdt_compat_id id)
79 {
80 	/* We allow reading of the 'unknown' ID for testing purposes */
81 	assert(id >= 0 && id < COMPAT_COUNT);
82 	return compat_names[id];
83 }
84 
85 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
86 		const char *prop_name, fdt_size_t *sizep)
87 {
88 	const fdt_addr_t *cell;
89 	int len;
90 
91 	debug("%s: %s: ", __func__, prop_name);
92 	cell = fdt_getprop(blob, node, prop_name, &len);
93 	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
94 		     len == sizeof(fdt_addr_t) * 2)) {
95 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
96 		if (sizep) {
97 			const fdt_size_t *size;
98 
99 			size = (fdt_size_t *)((char *)cell +
100 					sizeof(fdt_addr_t));
101 			*sizep = fdt_size_to_cpu(*size);
102 			debug("addr=%p, size=%p\n", (void *)addr,
103 			      (void *)*sizep);
104 		} else {
105 			debug("%p\n", (void *)addr);
106 		}
107 		return addr;
108 	}
109 	debug("(not found)\n");
110 	return FDT_ADDR_T_NONE;
111 }
112 
113 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
114 		const char *prop_name)
115 {
116 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
117 }
118 
119 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
120 		s32 default_val)
121 {
122 	const s32 *cell;
123 	int len;
124 
125 	debug("%s: %s: ", __func__, prop_name);
126 	cell = fdt_getprop(blob, node, prop_name, &len);
127 	if (cell && len >= sizeof(s32)) {
128 		s32 val = fdt32_to_cpu(cell[0]);
129 
130 		debug("%#x (%d)\n", val, val);
131 		return val;
132 	}
133 	debug("(not found)\n");
134 	return default_val;
135 }
136 
137 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
138 		uint64_t default_val)
139 {
140 	const uint64_t *cell64;
141 	int length;
142 
143 	cell64 = fdt_getprop(blob, node, prop_name, &length);
144 	if (!cell64 || length < sizeof(*cell64))
145 		return default_val;
146 
147 	return fdt64_to_cpu(*cell64);
148 }
149 
150 int fdtdec_get_is_enabled(const void *blob, int node)
151 {
152 	const char *cell;
153 
154 	/*
155 	 * It should say "okay", so only allow that. Some fdts use "ok" but
156 	 * this is a bug. Please fix your device tree source file. See here
157 	 * for discussion:
158 	 *
159 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
160 	 */
161 	cell = fdt_getprop(blob, node, "status", NULL);
162 	if (cell)
163 		return 0 == strcmp(cell, "okay");
164 	return 1;
165 }
166 
167 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
168 {
169 	enum fdt_compat_id id;
170 
171 	/* Search our drivers */
172 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
173 		if (0 == fdt_node_check_compatible(blob, node,
174 				compat_names[id]))
175 			return id;
176 	return COMPAT_UNKNOWN;
177 }
178 
179 int fdtdec_next_compatible(const void *blob, int node,
180 		enum fdt_compat_id id)
181 {
182 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
183 }
184 
185 int fdtdec_next_compatible_subnode(const void *blob, int node,
186 		enum fdt_compat_id id, int *depthp)
187 {
188 	do {
189 		node = fdt_next_node(blob, node, depthp);
190 	} while (*depthp > 1);
191 
192 	/* If this is a direct subnode, and compatible, return it */
193 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
194 						blob, node, compat_names[id]))
195 		return node;
196 
197 	return -FDT_ERR_NOTFOUND;
198 }
199 
200 int fdtdec_next_alias(const void *blob, const char *name,
201 		enum fdt_compat_id id, int *upto)
202 {
203 #define MAX_STR_LEN 20
204 	char str[MAX_STR_LEN + 20];
205 	int node, err;
206 
207 	/* snprintf() is not available */
208 	assert(strlen(name) < MAX_STR_LEN);
209 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
210 	node = fdt_path_offset(blob, str);
211 	if (node < 0)
212 		return node;
213 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
214 	if (err < 0)
215 		return err;
216 	if (err)
217 		return -FDT_ERR_NOTFOUND;
218 	(*upto)++;
219 	return node;
220 }
221 
222 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
223 			enum fdt_compat_id id, int *node_list, int maxcount)
224 {
225 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
226 
227 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
228 }
229 
230 /* TODO: Can we tighten this code up a little? */
231 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
232 			enum fdt_compat_id id, int *node_list, int maxcount)
233 {
234 	int name_len = strlen(name);
235 	int nodes[maxcount];
236 	int num_found = 0;
237 	int offset, node;
238 	int alias_node;
239 	int count;
240 	int i, j;
241 
242 	/* find the alias node if present */
243 	alias_node = fdt_path_offset(blob, "/aliases");
244 
245 	/*
246 	 * start with nothing, and we can assume that the root node can't
247 	 * match
248 	 */
249 	memset(nodes, '\0', sizeof(nodes));
250 
251 	/* First find all the compatible nodes */
252 	for (node = count = 0; node >= 0 && count < maxcount;) {
253 		node = fdtdec_next_compatible(blob, node, id);
254 		if (node >= 0)
255 			nodes[count++] = node;
256 	}
257 	if (node >= 0)
258 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
259 		       __func__, name);
260 
261 	/* Now find all the aliases */
262 	for (offset = fdt_first_property_offset(blob, alias_node);
263 			offset > 0;
264 			offset = fdt_next_property_offset(blob, offset)) {
265 		const struct fdt_property *prop;
266 		const char *path;
267 		int number;
268 		int found;
269 
270 		node = 0;
271 		prop = fdt_get_property_by_offset(blob, offset, NULL);
272 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
273 		if (prop->len && 0 == strncmp(path, name, name_len))
274 			node = fdt_path_offset(blob, prop->data);
275 		if (node <= 0)
276 			continue;
277 
278 		/* Get the alias number */
279 		number = simple_strtoul(path + name_len, NULL, 10);
280 		if (number < 0 || number >= maxcount) {
281 			debug("%s: warning: alias '%s' is out of range\n",
282 			       __func__, path);
283 			continue;
284 		}
285 
286 		/* Make sure the node we found is actually in our list! */
287 		found = -1;
288 		for (j = 0; j < count; j++)
289 			if (nodes[j] == node) {
290 				found = j;
291 				break;
292 			}
293 
294 		if (found == -1) {
295 			debug("%s: warning: alias '%s' points to a node "
296 				"'%s' that is missing or is not compatible "
297 				" with '%s'\n", __func__, path,
298 				fdt_get_name(blob, node, NULL),
299 			       compat_names[id]);
300 			continue;
301 		}
302 
303 		/*
304 		 * Add this node to our list in the right place, and mark
305 		 * it as done.
306 		 */
307 		if (fdtdec_get_is_enabled(blob, node)) {
308 			if (node_list[number]) {
309 				debug("%s: warning: alias '%s' requires that "
310 				      "a node be placed in the list in a "
311 				      "position which is already filled by "
312 				      "node '%s'\n", __func__, path,
313 				      fdt_get_name(blob, node, NULL));
314 				continue;
315 			}
316 			node_list[number] = node;
317 			if (number >= num_found)
318 				num_found = number + 1;
319 		}
320 		nodes[found] = 0;
321 	}
322 
323 	/* Add any nodes not mentioned by an alias */
324 	for (i = j = 0; i < maxcount; i++) {
325 		if (!node_list[i]) {
326 			for (; j < maxcount; j++)
327 				if (nodes[j] &&
328 					fdtdec_get_is_enabled(blob, nodes[j]))
329 					break;
330 
331 			/* Have we run out of nodes to add? */
332 			if (j == maxcount)
333 				break;
334 
335 			assert(!node_list[i]);
336 			node_list[i] = nodes[j++];
337 			if (i >= num_found)
338 				num_found = i + 1;
339 		}
340 	}
341 
342 	return num_found;
343 }
344 
345 int fdtdec_check_fdt(void)
346 {
347 	/*
348 	 * We must have an FDT, but we cannot panic() yet since the console
349 	 * is not ready. So for now, just assert(). Boards which need an early
350 	 * FDT (prior to console ready) will need to make their own
351 	 * arrangements and do their own checks.
352 	 */
353 	assert(!fdtdec_prepare_fdt());
354 	return 0;
355 }
356 
357 /*
358  * This function is a little odd in that it accesses global data. At some
359  * point if the architecture board.c files merge this will make more sense.
360  * Even now, it is common code.
361  */
362 int fdtdec_prepare_fdt(void)
363 {
364 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
365 	    fdt_check_header(gd->fdt_blob)) {
366 		printf("No valid FDT found - please append one to U-Boot "
367 			"binary, use u-boot-dtb.bin or define "
368 			"CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
369 		return -1;
370 	}
371 	return 0;
372 }
373 
374 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
375 {
376 	const u32 *phandle;
377 	int lookup;
378 
379 	debug("%s: %s\n", __func__, prop_name);
380 	phandle = fdt_getprop(blob, node, prop_name, NULL);
381 	if (!phandle)
382 		return -FDT_ERR_NOTFOUND;
383 
384 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
385 	return lookup;
386 }
387 
388 /**
389  * Look up a property in a node and check that it has a minimum length.
390  *
391  * @param blob		FDT blob
392  * @param node		node to examine
393  * @param prop_name	name of property to find
394  * @param min_len	minimum property length in bytes
395  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
396 			found, or -FDT_ERR_BADLAYOUT if not enough data
397  * @return pointer to cell, which is only valid if err == 0
398  */
399 static const void *get_prop_check_min_len(const void *blob, int node,
400 		const char *prop_name, int min_len, int *err)
401 {
402 	const void *cell;
403 	int len;
404 
405 	debug("%s: %s\n", __func__, prop_name);
406 	cell = fdt_getprop(blob, node, prop_name, &len);
407 	if (!cell)
408 		*err = -FDT_ERR_NOTFOUND;
409 	else if (len < min_len)
410 		*err = -FDT_ERR_BADLAYOUT;
411 	else
412 		*err = 0;
413 	return cell;
414 }
415 
416 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
417 		u32 *array, int count)
418 {
419 	const u32 *cell;
420 	int i, err = 0;
421 
422 	debug("%s: %s\n", __func__, prop_name);
423 	cell = get_prop_check_min_len(blob, node, prop_name,
424 				      sizeof(u32) * count, &err);
425 	if (!err) {
426 		for (i = 0; i < count; i++)
427 			array[i] = fdt32_to_cpu(cell[i]);
428 	}
429 	return err;
430 }
431 
432 const u32 *fdtdec_locate_array(const void *blob, int node,
433 			       const char *prop_name, int count)
434 {
435 	const u32 *cell;
436 	int err;
437 
438 	cell = get_prop_check_min_len(blob, node, prop_name,
439 				      sizeof(u32) * count, &err);
440 	return err ? NULL : cell;
441 }
442 
443 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
444 {
445 	const s32 *cell;
446 	int len;
447 
448 	debug("%s: %s\n", __func__, prop_name);
449 	cell = fdt_getprop(blob, node, prop_name, &len);
450 	return cell != NULL;
451 }
452 
453 /**
454  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
455  * terminating item.
456  *
457  * @param blob		FDT blob to use
458  * @param node		Node to look at
459  * @param prop_name	Node property name
460  * @param gpio		Array of gpio elements to fill from FDT. This will be
461  *			untouched if either 0 or an error is returned
462  * @param max_count	Maximum number of elements allowed
463  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
464  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
465  */
466 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
467 		struct fdt_gpio_state *gpio, int max_count)
468 {
469 	const struct fdt_property *prop;
470 	const u32 *cell;
471 	const char *name;
472 	int len, i;
473 
474 	debug("%s: %s\n", __func__, prop_name);
475 	assert(max_count > 0);
476 	prop = fdt_get_property(blob, node, prop_name, &len);
477 	if (!prop) {
478 		debug("%s: property '%s' missing\n", __func__, prop_name);
479 		return -FDT_ERR_NOTFOUND;
480 	}
481 
482 	/* We will use the name to tag the GPIO */
483 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
484 	cell = (u32 *)prop->data;
485 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
486 	if (len > max_count) {
487 		debug(" %s: too many GPIOs / cells for "
488 			"property '%s'\n", __func__, prop_name);
489 		return -FDT_ERR_BADLAYOUT;
490 	}
491 
492 	/* Read out the GPIO data from the cells */
493 	for (i = 0; i < len; i++, cell += 3) {
494 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
495 		gpio[i].flags = fdt32_to_cpu(cell[2]);
496 		gpio[i].name = name;
497 	}
498 
499 	return len;
500 }
501 
502 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
503 		struct fdt_gpio_state *gpio)
504 {
505 	int err;
506 
507 	debug("%s: %s\n", __func__, prop_name);
508 	gpio->gpio = FDT_GPIO_NONE;
509 	gpio->name = NULL;
510 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
511 	return err == 1 ? 0 : err;
512 }
513 
514 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
515 {
516 	int val;
517 
518 	if (!fdt_gpio_isvalid(gpio))
519 		return -1;
520 
521 	val = gpio_get_value(gpio->gpio);
522 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
523 }
524 
525 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
526 {
527 	if (!fdt_gpio_isvalid(gpio))
528 		return -1;
529 
530 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
531 	return gpio_set_value(gpio->gpio, val);
532 }
533 
534 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
535 {
536 	/*
537 	 * Return success if there is no GPIO defined. This is used for
538 	 * optional GPIOs)
539 	 */
540 	if (!fdt_gpio_isvalid(gpio))
541 		return 0;
542 
543 	if (gpio_request(gpio->gpio, gpio->name))
544 		return -1;
545 	return 0;
546 }
547 
548 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
549 		u8 *array, int count)
550 {
551 	const u8 *cell;
552 	int err;
553 
554 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
555 	if (!err)
556 		memcpy(array, cell, count);
557 	return err;
558 }
559 
560 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
561 			     const char *prop_name, int count)
562 {
563 	const u8 *cell;
564 	int err;
565 
566 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
567 	if (err)
568 		return NULL;
569 	return cell;
570 }
571 
572 int fdtdec_get_config_int(const void *blob, const char *prop_name,
573 		int default_val)
574 {
575 	int config_node;
576 
577 	debug("%s: %s\n", __func__, prop_name);
578 	config_node = fdt_path_offset(blob, "/config");
579 	if (config_node < 0)
580 		return default_val;
581 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
582 }
583 
584 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
585 {
586 	int config_node;
587 	const void *prop;
588 
589 	debug("%s: %s\n", __func__, prop_name);
590 	config_node = fdt_path_offset(blob, "/config");
591 	if (config_node < 0)
592 		return 0;
593 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
594 
595 	return prop != NULL;
596 }
597 
598 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
599 {
600 	const char *nodep;
601 	int nodeoffset;
602 	int len;
603 
604 	debug("%s: %s\n", __func__, prop_name);
605 	nodeoffset = fdt_path_offset(blob, "/config");
606 	if (nodeoffset < 0)
607 		return NULL;
608 
609 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
610 	if (!nodep)
611 		return NULL;
612 
613 	return (char *)nodep;
614 }
615 
616 int fdtdec_decode_region(const void *blob, int node,
617 		const char *prop_name, void **ptrp, size_t *size)
618 {
619 	const fdt_addr_t *cell;
620 	int len;
621 
622 	debug("%s: %s\n", __func__, prop_name);
623 	cell = fdt_getprop(blob, node, prop_name, &len);
624 	if (!cell || (len != sizeof(fdt_addr_t) * 2))
625 		return -1;
626 
627 	*ptrp = (void *)fdt_addr_to_cpu(*cell);
628 	*size = fdt_size_to_cpu(cell[1]);
629 	debug("%s: size=%zx\n", __func__, *size);
630 	return 0;
631 }
632