xref: /openbmc/u-boot/lib/fdtdec.c (revision 2a9ae6e02f190e8c83450aab9099a9fb5ec48cc9)
1 /*
2  * Copyright (c) 2011 The Chromium OS Authors.
3  * SPDX-License-Identifier:	GPL-2.0+
4  */
5 
6 #ifndef USE_HOSTCC
7 #include <common.h>
8 #include <errno.h>
9 #include <serial.h>
10 #include <libfdt.h>
11 #include <fdtdec.h>
12 #include <linux/ctype.h>
13 
14 #include <asm/gpio.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 /*
19  * Here are the type we know about. One day we might allow drivers to
20  * register. For now we just put them here. The COMPAT macro allows us to
21  * turn this into a sparse list later, and keeps the ID with the name.
22  */
23 #define COMPAT(id, name) name
24 static const char * const compat_names[COMPAT_COUNT] = {
25 	COMPAT(UNKNOWN, "<none>"),
26 	COMPAT(NVIDIA_TEGRA20_USB, "nvidia,tegra20-ehci"),
27 	COMPAT(NVIDIA_TEGRA30_USB, "nvidia,tegra30-ehci"),
28 	COMPAT(NVIDIA_TEGRA114_USB, "nvidia,tegra114-ehci"),
29 	COMPAT(NVIDIA_TEGRA114_I2C, "nvidia,tegra114-i2c"),
30 	COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"),
31 	COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"),
32 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
33 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
34 	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
35 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
36 	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
37 	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
38 	COMPAT(NVIDIA_TEGRA124_SDMMC, "nvidia,tegra124-sdhci"),
39 	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
40 	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
41 	COMPAT(NVIDIA_TEGRA20_SFLASH, "nvidia,tegra20-sflash"),
42 	COMPAT(NVIDIA_TEGRA20_SLINK, "nvidia,tegra20-slink"),
43 	COMPAT(NVIDIA_TEGRA114_SPI, "nvidia,tegra114-spi"),
44 	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
45 	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
46 	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
47 	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
48 	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
49 	COMPAT(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"),
50 	COMPAT(GOOGLE_CROS_EC, "google,cros-ec"),
51 	COMPAT(GOOGLE_CROS_EC_KEYB, "google,cros-ec-keyb"),
52 	COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
53 	COMPAT(SAMSUNG_EXYNOS5_XHCI, "samsung,exynos5250-xhci"),
54 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
55 	COMPAT(SAMSUNG_EXYNOS5_USB3_PHY, "samsung,exynos5250-usb3-phy"),
56 	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
57 	COMPAT(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
58 	COMPAT(SAMSUNG_EXYNOS_MIPI_DSI, "samsung,exynos-mipi-dsi"),
59 	COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
60 	COMPAT(SAMSUNG_EXYNOS_DWMMC, "samsung,exynos-dwmmc"),
61 	COMPAT(SAMSUNG_EXYNOS_MMC, "samsung,exynos-mmc"),
62 	COMPAT(SAMSUNG_EXYNOS_SERIAL, "samsung,exynos4210-uart"),
63 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
64 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
65 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
66 	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
67 	COMPAT(INFINEON_SLB9645_TPM, "infineon,slb9645-tpm"),
68 	COMPAT(SAMSUNG_EXYNOS5_I2C, "samsung,exynos5-hsi2c"),
69 	COMPAT(SANDBOX_HOST_EMULATION, "sandbox,host-emulation"),
70 	COMPAT(SANDBOX_LCD_SDL, "sandbox,lcd-sdl"),
71 	COMPAT(TI_TPS65090, "ti,tps65090"),
72 	COMPAT(COMPAT_NXP_PTN3460, "nxp,ptn3460"),
73 };
74 
75 const char *fdtdec_get_compatible(enum fdt_compat_id id)
76 {
77 	/* We allow reading of the 'unknown' ID for testing purposes */
78 	assert(id >= 0 && id < COMPAT_COUNT);
79 	return compat_names[id];
80 }
81 
82 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
83 		const char *prop_name, fdt_size_t *sizep)
84 {
85 	const fdt_addr_t *cell;
86 	int len;
87 
88 	debug("%s: %s: ", __func__, prop_name);
89 	cell = fdt_getprop(blob, node, prop_name, &len);
90 	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
91 		     len == sizeof(fdt_addr_t) * 2)) {
92 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
93 		if (sizep) {
94 			const fdt_size_t *size;
95 
96 			size = (fdt_size_t *)((char *)cell +
97 					sizeof(fdt_addr_t));
98 			*sizep = fdt_size_to_cpu(*size);
99 			debug("addr=%08lx, size=%08x\n",
100 			      (ulong)addr, *sizep);
101 		} else {
102 			debug("%08lx\n", (ulong)addr);
103 		}
104 		return addr;
105 	}
106 	debug("(not found)\n");
107 	return FDT_ADDR_T_NONE;
108 }
109 
110 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
111 		const char *prop_name)
112 {
113 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
114 }
115 
116 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
117 		uint64_t default_val)
118 {
119 	const uint64_t *cell64;
120 	int length;
121 
122 	cell64 = fdt_getprop(blob, node, prop_name, &length);
123 	if (!cell64 || length < sizeof(*cell64))
124 		return default_val;
125 
126 	return fdt64_to_cpu(*cell64);
127 }
128 
129 int fdtdec_get_is_enabled(const void *blob, int node)
130 {
131 	const char *cell;
132 
133 	/*
134 	 * It should say "okay", so only allow that. Some fdts use "ok" but
135 	 * this is a bug. Please fix your device tree source file. See here
136 	 * for discussion:
137 	 *
138 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
139 	 */
140 	cell = fdt_getprop(blob, node, "status", NULL);
141 	if (cell)
142 		return 0 == strcmp(cell, "okay");
143 	return 1;
144 }
145 
146 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
147 {
148 	enum fdt_compat_id id;
149 
150 	/* Search our drivers */
151 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
152 		if (0 == fdt_node_check_compatible(blob, node,
153 				compat_names[id]))
154 			return id;
155 	return COMPAT_UNKNOWN;
156 }
157 
158 int fdtdec_next_compatible(const void *blob, int node,
159 		enum fdt_compat_id id)
160 {
161 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
162 }
163 
164 int fdtdec_next_compatible_subnode(const void *blob, int node,
165 		enum fdt_compat_id id, int *depthp)
166 {
167 	do {
168 		node = fdt_next_node(blob, node, depthp);
169 	} while (*depthp > 1);
170 
171 	/* If this is a direct subnode, and compatible, return it */
172 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
173 						blob, node, compat_names[id]))
174 		return node;
175 
176 	return -FDT_ERR_NOTFOUND;
177 }
178 
179 int fdtdec_next_alias(const void *blob, const char *name,
180 		enum fdt_compat_id id, int *upto)
181 {
182 #define MAX_STR_LEN 20
183 	char str[MAX_STR_LEN + 20];
184 	int node, err;
185 
186 	/* snprintf() is not available */
187 	assert(strlen(name) < MAX_STR_LEN);
188 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
189 	node = fdt_path_offset(blob, str);
190 	if (node < 0)
191 		return node;
192 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
193 	if (err < 0)
194 		return err;
195 	if (err)
196 		return -FDT_ERR_NOTFOUND;
197 	(*upto)++;
198 	return node;
199 }
200 
201 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
202 			enum fdt_compat_id id, int *node_list, int maxcount)
203 {
204 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
205 
206 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
207 }
208 
209 /* TODO: Can we tighten this code up a little? */
210 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
211 			enum fdt_compat_id id, int *node_list, int maxcount)
212 {
213 	int name_len = strlen(name);
214 	int nodes[maxcount];
215 	int num_found = 0;
216 	int offset, node;
217 	int alias_node;
218 	int count;
219 	int i, j;
220 
221 	/* find the alias node if present */
222 	alias_node = fdt_path_offset(blob, "/aliases");
223 
224 	/*
225 	 * start with nothing, and we can assume that the root node can't
226 	 * match
227 	 */
228 	memset(nodes, '\0', sizeof(nodes));
229 
230 	/* First find all the compatible nodes */
231 	for (node = count = 0; node >= 0 && count < maxcount;) {
232 		node = fdtdec_next_compatible(blob, node, id);
233 		if (node >= 0)
234 			nodes[count++] = node;
235 	}
236 	if (node >= 0)
237 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
238 		       __func__, name);
239 
240 	/* Now find all the aliases */
241 	for (offset = fdt_first_property_offset(blob, alias_node);
242 			offset > 0;
243 			offset = fdt_next_property_offset(blob, offset)) {
244 		const struct fdt_property *prop;
245 		const char *path;
246 		int number;
247 		int found;
248 
249 		node = 0;
250 		prop = fdt_get_property_by_offset(blob, offset, NULL);
251 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
252 		if (prop->len && 0 == strncmp(path, name, name_len))
253 			node = fdt_path_offset(blob, prop->data);
254 		if (node <= 0)
255 			continue;
256 
257 		/* Get the alias number */
258 		number = simple_strtoul(path + name_len, NULL, 10);
259 		if (number < 0 || number >= maxcount) {
260 			debug("%s: warning: alias '%s' is out of range\n",
261 			       __func__, path);
262 			continue;
263 		}
264 
265 		/* Make sure the node we found is actually in our list! */
266 		found = -1;
267 		for (j = 0; j < count; j++)
268 			if (nodes[j] == node) {
269 				found = j;
270 				break;
271 			}
272 
273 		if (found == -1) {
274 			debug("%s: warning: alias '%s' points to a node "
275 				"'%s' that is missing or is not compatible "
276 				" with '%s'\n", __func__, path,
277 				fdt_get_name(blob, node, NULL),
278 			       compat_names[id]);
279 			continue;
280 		}
281 
282 		/*
283 		 * Add this node to our list in the right place, and mark
284 		 * it as done.
285 		 */
286 		if (fdtdec_get_is_enabled(blob, node)) {
287 			if (node_list[number]) {
288 				debug("%s: warning: alias '%s' requires that "
289 				      "a node be placed in the list in a "
290 				      "position which is already filled by "
291 				      "node '%s'\n", __func__, path,
292 				      fdt_get_name(blob, node, NULL));
293 				continue;
294 			}
295 			node_list[number] = node;
296 			if (number >= num_found)
297 				num_found = number + 1;
298 		}
299 		nodes[found] = 0;
300 	}
301 
302 	/* Add any nodes not mentioned by an alias */
303 	for (i = j = 0; i < maxcount; i++) {
304 		if (!node_list[i]) {
305 			for (; j < maxcount; j++)
306 				if (nodes[j] &&
307 					fdtdec_get_is_enabled(blob, nodes[j]))
308 					break;
309 
310 			/* Have we run out of nodes to add? */
311 			if (j == maxcount)
312 				break;
313 
314 			assert(!node_list[i]);
315 			node_list[i] = nodes[j++];
316 			if (i >= num_found)
317 				num_found = i + 1;
318 		}
319 	}
320 
321 	return num_found;
322 }
323 
324 int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
325 			 int *seqp)
326 {
327 	int base_len = strlen(base);
328 	const char *find_name;
329 	int find_namelen;
330 	int prop_offset;
331 	int aliases;
332 
333 	find_name = fdt_get_name(blob, offset, &find_namelen);
334 	debug("Looking for '%s' at %d, name %s\n", base, offset, find_name);
335 
336 	aliases = fdt_path_offset(blob, "/aliases");
337 	for (prop_offset = fdt_first_property_offset(blob, aliases);
338 	     prop_offset > 0;
339 	     prop_offset = fdt_next_property_offset(blob, prop_offset)) {
340 		const char *prop;
341 		const char *name;
342 		const char *slash;
343 		const char *p;
344 		int len;
345 
346 		prop = fdt_getprop_by_offset(blob, prop_offset, &name, &len);
347 		debug("   - %s, %s\n", name, prop);
348 		if (len < find_namelen || *prop != '/' || prop[len - 1] ||
349 		    strncmp(name, base, base_len))
350 			continue;
351 
352 		slash = strrchr(prop, '/');
353 		if (strcmp(slash + 1, find_name))
354 			continue;
355 		for (p = name; *p; p++) {
356 			if (isdigit(*p)) {
357 				*seqp = simple_strtoul(p, NULL, 10);
358 				debug("Found seq %d\n", *seqp);
359 				return 0;
360 			}
361 		}
362 	}
363 
364 	debug("Not found\n");
365 	return -ENOENT;
366 }
367 
368 int fdtdec_get_alias_node(const void *blob, const char *name)
369 {
370 	const char *prop;
371 	int alias_node;
372 	int len;
373 
374 	if (!blob)
375 		return -FDT_ERR_NOTFOUND;
376 	alias_node = fdt_path_offset(blob, "/aliases");
377 	prop = fdt_getprop(blob, alias_node, name, &len);
378 	if (!prop)
379 		return -FDT_ERR_NOTFOUND;
380 	return fdt_path_offset(blob, prop);
381 }
382 
383 int fdtdec_get_chosen_node(const void *blob, const char *name)
384 {
385 	const char *prop;
386 	int chosen_node;
387 	int len;
388 
389 	if (!blob)
390 		return -FDT_ERR_NOTFOUND;
391 	chosen_node = fdt_path_offset(blob, "/chosen");
392 	prop = fdt_getprop(blob, chosen_node, name, &len);
393 	if (!prop)
394 		return -FDT_ERR_NOTFOUND;
395 	return fdt_path_offset(blob, prop);
396 }
397 
398 int fdtdec_check_fdt(void)
399 {
400 	/*
401 	 * We must have an FDT, but we cannot panic() yet since the console
402 	 * is not ready. So for now, just assert(). Boards which need an early
403 	 * FDT (prior to console ready) will need to make their own
404 	 * arrangements and do their own checks.
405 	 */
406 	assert(!fdtdec_prepare_fdt());
407 	return 0;
408 }
409 
410 /*
411  * This function is a little odd in that it accesses global data. At some
412  * point if the architecture board.c files merge this will make more sense.
413  * Even now, it is common code.
414  */
415 int fdtdec_prepare_fdt(void)
416 {
417 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
418 	    fdt_check_header(gd->fdt_blob)) {
419 		printf("No valid FDT found - please append one to U-Boot "
420 			"binary, use u-boot-dtb.bin or define "
421 			"CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
422 		return -1;
423 	}
424 	return 0;
425 }
426 
427 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
428 {
429 	const u32 *phandle;
430 	int lookup;
431 
432 	debug("%s: %s\n", __func__, prop_name);
433 	phandle = fdt_getprop(blob, node, prop_name, NULL);
434 	if (!phandle)
435 		return -FDT_ERR_NOTFOUND;
436 
437 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
438 	return lookup;
439 }
440 
441 /**
442  * Look up a property in a node and check that it has a minimum length.
443  *
444  * @param blob		FDT blob
445  * @param node		node to examine
446  * @param prop_name	name of property to find
447  * @param min_len	minimum property length in bytes
448  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
449 			found, or -FDT_ERR_BADLAYOUT if not enough data
450  * @return pointer to cell, which is only valid if err == 0
451  */
452 static const void *get_prop_check_min_len(const void *blob, int node,
453 		const char *prop_name, int min_len, int *err)
454 {
455 	const void *cell;
456 	int len;
457 
458 	debug("%s: %s\n", __func__, prop_name);
459 	cell = fdt_getprop(blob, node, prop_name, &len);
460 	if (!cell)
461 		*err = -FDT_ERR_NOTFOUND;
462 	else if (len < min_len)
463 		*err = -FDT_ERR_BADLAYOUT;
464 	else
465 		*err = 0;
466 	return cell;
467 }
468 
469 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
470 		u32 *array, int count)
471 {
472 	const u32 *cell;
473 	int i, err = 0;
474 
475 	debug("%s: %s\n", __func__, prop_name);
476 	cell = get_prop_check_min_len(blob, node, prop_name,
477 				      sizeof(u32) * count, &err);
478 	if (!err) {
479 		for (i = 0; i < count; i++)
480 			array[i] = fdt32_to_cpu(cell[i]);
481 	}
482 	return err;
483 }
484 
485 const u32 *fdtdec_locate_array(const void *blob, int node,
486 			       const char *prop_name, int count)
487 {
488 	const u32 *cell;
489 	int err;
490 
491 	cell = get_prop_check_min_len(blob, node, prop_name,
492 				      sizeof(u32) * count, &err);
493 	return err ? NULL : cell;
494 }
495 
496 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
497 {
498 	const s32 *cell;
499 	int len;
500 
501 	debug("%s: %s\n", __func__, prop_name);
502 	cell = fdt_getprop(blob, node, prop_name, &len);
503 	return cell != NULL;
504 }
505 
506 /**
507  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
508  * terminating item.
509  *
510  * @param blob		FDT blob to use
511  * @param node		Node to look at
512  * @param prop_name	Node property name
513  * @param gpio		Array of gpio elements to fill from FDT. This will be
514  *			untouched if either 0 or an error is returned
515  * @param max_count	Maximum number of elements allowed
516  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
517  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
518  */
519 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
520 		struct fdt_gpio_state *gpio, int max_count)
521 {
522 	const struct fdt_property *prop;
523 	const u32 *cell;
524 	const char *name;
525 	int len, i;
526 
527 	debug("%s: %s\n", __func__, prop_name);
528 	assert(max_count > 0);
529 	prop = fdt_get_property(blob, node, prop_name, &len);
530 	if (!prop) {
531 		debug("%s: property '%s' missing\n", __func__, prop_name);
532 		return -FDT_ERR_NOTFOUND;
533 	}
534 
535 	/* We will use the name to tag the GPIO */
536 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
537 	cell = (u32 *)prop->data;
538 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
539 	if (len > max_count) {
540 		debug(" %s: too many GPIOs / cells for "
541 			"property '%s'\n", __func__, prop_name);
542 		return -FDT_ERR_BADLAYOUT;
543 	}
544 
545 	/* Read out the GPIO data from the cells */
546 	for (i = 0; i < len; i++, cell += 3) {
547 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
548 		gpio[i].flags = fdt32_to_cpu(cell[2]);
549 		gpio[i].name = name;
550 	}
551 
552 	return len;
553 }
554 
555 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
556 		struct fdt_gpio_state *gpio)
557 {
558 	int err;
559 
560 	debug("%s: %s\n", __func__, prop_name);
561 	gpio->gpio = FDT_GPIO_NONE;
562 	gpio->name = NULL;
563 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
564 	return err == 1 ? 0 : err;
565 }
566 
567 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
568 {
569 	int val;
570 
571 	if (!fdt_gpio_isvalid(gpio))
572 		return -1;
573 
574 	val = gpio_get_value(gpio->gpio);
575 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
576 }
577 
578 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
579 {
580 	if (!fdt_gpio_isvalid(gpio))
581 		return -1;
582 
583 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
584 	return gpio_set_value(gpio->gpio, val);
585 }
586 
587 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
588 {
589 	/*
590 	 * Return success if there is no GPIO defined. This is used for
591 	 * optional GPIOs)
592 	 */
593 	if (!fdt_gpio_isvalid(gpio))
594 		return 0;
595 
596 	if (gpio_request(gpio->gpio, gpio->name))
597 		return -1;
598 	return 0;
599 }
600 
601 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
602 		u8 *array, int count)
603 {
604 	const u8 *cell;
605 	int err;
606 
607 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
608 	if (!err)
609 		memcpy(array, cell, count);
610 	return err;
611 }
612 
613 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
614 			     const char *prop_name, int count)
615 {
616 	const u8 *cell;
617 	int err;
618 
619 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
620 	if (err)
621 		return NULL;
622 	return cell;
623 }
624 
625 int fdtdec_get_config_int(const void *blob, const char *prop_name,
626 		int default_val)
627 {
628 	int config_node;
629 
630 	debug("%s: %s\n", __func__, prop_name);
631 	config_node = fdt_path_offset(blob, "/config");
632 	if (config_node < 0)
633 		return default_val;
634 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
635 }
636 
637 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
638 {
639 	int config_node;
640 	const void *prop;
641 
642 	debug("%s: %s\n", __func__, prop_name);
643 	config_node = fdt_path_offset(blob, "/config");
644 	if (config_node < 0)
645 		return 0;
646 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
647 
648 	return prop != NULL;
649 }
650 
651 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
652 {
653 	const char *nodep;
654 	int nodeoffset;
655 	int len;
656 
657 	debug("%s: %s\n", __func__, prop_name);
658 	nodeoffset = fdt_path_offset(blob, "/config");
659 	if (nodeoffset < 0)
660 		return NULL;
661 
662 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
663 	if (!nodep)
664 		return NULL;
665 
666 	return (char *)nodep;
667 }
668 
669 int fdtdec_decode_region(const void *blob, int node,
670 		const char *prop_name, void **ptrp, size_t *size)
671 {
672 	const fdt_addr_t *cell;
673 	int len;
674 
675 	debug("%s: %s\n", __func__, prop_name);
676 	cell = fdt_getprop(blob, node, prop_name, &len);
677 	if (!cell || (len != sizeof(fdt_addr_t) * 2))
678 		return -1;
679 
680 	*ptrp = map_sysmem(fdt_addr_to_cpu(*cell), *size);
681 	*size = fdt_size_to_cpu(cell[1]);
682 	debug("%s: size=%zx\n", __func__, *size);
683 	return 0;
684 }
685 
686 /**
687  * Read a flash entry from the fdt
688  *
689  * @param blob		FDT blob
690  * @param node		Offset of node to read
691  * @param name		Name of node being read
692  * @param entry		Place to put offset and size of this node
693  * @return 0 if ok, -ve on error
694  */
695 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
696 			   struct fmap_entry *entry)
697 {
698 	u32 reg[2];
699 
700 	if (fdtdec_get_int_array(blob, node, "reg", reg, 2)) {
701 		debug("Node '%s' has bad/missing 'reg' property\n", name);
702 		return -FDT_ERR_NOTFOUND;
703 	}
704 	entry->offset = reg[0];
705 	entry->length = reg[1];
706 
707 	return 0;
708 }
709 #endif
710