xref: /openbmc/u-boot/lib/fdtdec.c (revision d3c083a9)
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 <dm.h>
9 #include <errno.h>
10 #include <serial.h>
11 #include <libfdt.h>
12 #include <fdt_support.h>
13 #include <fdtdec.h>
14 #include <asm/sections.h>
15 #include <linux/ctype.h>
16 
17 DECLARE_GLOBAL_DATA_PTR;
18 
19 /*
20  * Here are the type we know about. One day we might allow drivers to
21  * register. For now we just put them here. The COMPAT macro allows us to
22  * turn this into a sparse list later, and keeps the ID with the name.
23  *
24  * NOTE: This list is basically a TODO list for things that need to be
25  * converted to driver model. So don't add new things here unless there is a
26  * good reason why driver-model conversion is infeasible. Examples include
27  * things which are used before driver model is available.
28  */
29 #define COMPAT(id, name) name
30 static const char * const compat_names[COMPAT_COUNT] = {
31 	COMPAT(UNKNOWN, "<none>"),
32 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
33 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
34 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
35 	COMPAT(NVIDIA_TEGRA124_PMC, "nvidia,tegra124-pmc"),
36 	COMPAT(NVIDIA_TEGRA186_SDMMC, "nvidia,tegra186-sdhci"),
37 	COMPAT(NVIDIA_TEGRA210_SDMMC, "nvidia,tegra210-sdhci"),
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_TEGRA124_XUSB_PADCTL, "nvidia,tegra124-xusb-padctl"),
42 	COMPAT(NVIDIA_TEGRA210_XUSB_PADCTL, "nvidia,tegra210-xusb-padctl"),
43 	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
44 	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
45 	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
46 	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
47 	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
48 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
49 	COMPAT(SAMSUNG_EXYNOS5_USB3_PHY, "samsung,exynos5250-usb3-phy"),
50 	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
51 	COMPAT(SAMSUNG_EXYNOS_MIPI_DSI, "samsung,exynos-mipi-dsi"),
52 	COMPAT(SAMSUNG_EXYNOS_DWMMC, "samsung,exynos-dwmmc"),
53 	COMPAT(SAMSUNG_EXYNOS_MMC, "samsung,exynos-mmc"),
54 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686"),
55 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
56 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
57 	COMPAT(SAMSUNG_EXYNOS5_I2C, "samsung,exynos5-hsi2c"),
58 	COMPAT(SAMSUNG_EXYNOS_SYSMMU, "samsung,sysmmu-v3.3"),
59 	COMPAT(INTEL_MICROCODE, "intel,microcode"),
60 	COMPAT(AMS_AS3722, "ams,as3722"),
61 	COMPAT(INTEL_QRK_MRC, "intel,quark-mrc"),
62 	COMPAT(ALTERA_SOCFPGA_DWMAC, "altr,socfpga-stmmac"),
63 	COMPAT(ALTERA_SOCFPGA_DWMMC, "altr,socfpga-dw-mshc"),
64 	COMPAT(ALTERA_SOCFPGA_DWC2USB, "snps,dwc2"),
65 	COMPAT(INTEL_BAYTRAIL_FSP, "intel,baytrail-fsp"),
66 	COMPAT(INTEL_BAYTRAIL_FSP_MDP, "intel,baytrail-fsp-mdp"),
67 	COMPAT(INTEL_IVYBRIDGE_FSP, "intel,ivybridge-fsp"),
68 	COMPAT(COMPAT_SUNXI_NAND, "allwinner,sun4i-a10-nand"),
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_fixed(const void *blob, int node,
79 		const char *prop_name, int index, int na, int ns,
80 		fdt_size_t *sizep, bool translate)
81 {
82 	const fdt32_t *prop, *prop_end;
83 	const fdt32_t *prop_addr, *prop_size, *prop_after_size;
84 	int len;
85 	fdt_addr_t addr;
86 
87 	debug("%s: %s: ", __func__, prop_name);
88 
89 	if (na > (sizeof(fdt_addr_t) / sizeof(fdt32_t))) {
90 		debug("(na too large for fdt_addr_t type)\n");
91 		return FDT_ADDR_T_NONE;
92 	}
93 
94 	if (ns > (sizeof(fdt_size_t) / sizeof(fdt32_t))) {
95 		debug("(ns too large for fdt_size_t type)\n");
96 		return FDT_ADDR_T_NONE;
97 	}
98 
99 	prop = fdt_getprop(blob, node, prop_name, &len);
100 	if (!prop) {
101 		debug("(not found)\n");
102 		return FDT_ADDR_T_NONE;
103 	}
104 	prop_end = prop + (len / sizeof(*prop));
105 
106 	prop_addr = prop + (index * (na + ns));
107 	prop_size = prop_addr + na;
108 	prop_after_size = prop_size + ns;
109 	if (prop_after_size > prop_end) {
110 		debug("(not enough data: expected >= %d cells, got %d cells)\n",
111 		      (u32)(prop_after_size - prop), ((u32)(prop_end - prop)));
112 		return FDT_ADDR_T_NONE;
113 	}
114 
115 #if !defined(CONFIG_SPL_BUILD) && defined(CONFIG_OF_LIBFDT)
116 	if (translate)
117 		addr = fdt_translate_address(blob, node, prop_addr);
118 	else
119 #endif
120 		addr = fdtdec_get_number(prop_addr, na);
121 
122 	if (sizep) {
123 		*sizep = fdtdec_get_number(prop_size, ns);
124 		debug("addr=%08llx, size=%llx\n", (unsigned long long)addr,
125 		      (unsigned long long)*sizep);
126 	} else {
127 		debug("addr=%08llx\n", (unsigned long long)addr);
128 	}
129 
130 	return addr;
131 }
132 
133 fdt_addr_t fdtdec_get_addr_size_auto_parent(const void *blob, int parent,
134 		int node, const char *prop_name, int index, fdt_size_t *sizep,
135 		bool translate)
136 {
137 	int na, ns;
138 
139 	debug("%s: ", __func__);
140 
141 	na = fdt_address_cells(blob, parent);
142 	if (na < 1) {
143 		debug("(bad #address-cells)\n");
144 		return FDT_ADDR_T_NONE;
145 	}
146 
147 	ns = fdt_size_cells(blob, parent);
148 	if (ns < 0) {
149 		debug("(bad #size-cells)\n");
150 		return FDT_ADDR_T_NONE;
151 	}
152 
153 	debug("na=%d, ns=%d, ", na, ns);
154 
155 	return fdtdec_get_addr_size_fixed(blob, node, prop_name, index, na,
156 					  ns, sizep, translate);
157 }
158 
159 fdt_addr_t fdtdec_get_addr_size_auto_noparent(const void *blob, int node,
160 		const char *prop_name, int index, fdt_size_t *sizep,
161 		bool translate)
162 {
163 	int parent;
164 
165 	debug("%s: ", __func__);
166 
167 	parent = fdt_parent_offset(blob, node);
168 	if (parent < 0) {
169 		debug("(no parent found)\n");
170 		return FDT_ADDR_T_NONE;
171 	}
172 
173 	return fdtdec_get_addr_size_auto_parent(blob, parent, node, prop_name,
174 						index, sizep, translate);
175 }
176 
177 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
178 		const char *prop_name, fdt_size_t *sizep)
179 {
180 	int ns = sizep ? (sizeof(fdt_size_t) / sizeof(fdt32_t)) : 0;
181 
182 	return fdtdec_get_addr_size_fixed(blob, node, prop_name, 0,
183 					  sizeof(fdt_addr_t) / sizeof(fdt32_t),
184 					  ns, sizep, false);
185 }
186 
187 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
188 		const char *prop_name)
189 {
190 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
191 }
192 
193 #if defined(CONFIG_PCI) && defined(CONFIG_DM_PCI)
194 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
195 		const char *prop_name, struct fdt_pci_addr *addr)
196 {
197 	const u32 *cell;
198 	int len;
199 	int ret = -ENOENT;
200 
201 	debug("%s: %s: ", __func__, prop_name);
202 
203 	/*
204 	 * If we follow the pci bus bindings strictly, we should check
205 	 * the value of the node's parent node's #address-cells and
206 	 * #size-cells. They need to be 3 and 2 accordingly. However,
207 	 * for simplicity we skip the check here.
208 	 */
209 	cell = fdt_getprop(blob, node, prop_name, &len);
210 	if (!cell)
211 		goto fail;
212 
213 	if ((len % FDT_PCI_REG_SIZE) == 0) {
214 		int num = len / FDT_PCI_REG_SIZE;
215 		int i;
216 
217 		for (i = 0; i < num; i++) {
218 			debug("pci address #%d: %08lx %08lx %08lx\n", i,
219 			      (ulong)fdt32_to_cpu(cell[0]),
220 			      (ulong)fdt32_to_cpu(cell[1]),
221 			      (ulong)fdt32_to_cpu(cell[2]));
222 			if ((fdt32_to_cpu(*cell) & type) == type) {
223 				addr->phys_hi = fdt32_to_cpu(cell[0]);
224 				addr->phys_mid = fdt32_to_cpu(cell[1]);
225 				addr->phys_lo = fdt32_to_cpu(cell[1]);
226 				break;
227 			} else {
228 				cell += (FDT_PCI_ADDR_CELLS +
229 					 FDT_PCI_SIZE_CELLS);
230 			}
231 		}
232 
233 		if (i == num) {
234 			ret = -ENXIO;
235 			goto fail;
236 		}
237 
238 		return 0;
239 	} else {
240 		ret = -EINVAL;
241 	}
242 
243 fail:
244 	debug("(not found)\n");
245 	return ret;
246 }
247 
248 int fdtdec_get_pci_vendev(const void *blob, int node, u16 *vendor, u16 *device)
249 {
250 	const char *list, *end;
251 	int len;
252 
253 	list = fdt_getprop(blob, node, "compatible", &len);
254 	if (!list)
255 		return -ENOENT;
256 
257 	end = list + len;
258 	while (list < end) {
259 		char *s;
260 
261 		len = strlen(list);
262 		if (len >= strlen("pciVVVV,DDDD")) {
263 			s = strstr(list, "pci");
264 
265 			/*
266 			 * check if the string is something like pciVVVV,DDDD.RR
267 			 * or just pciVVVV,DDDD
268 			 */
269 			if (s && s[7] == ',' &&
270 			    (s[12] == '.' || s[12] == 0)) {
271 				s += 3;
272 				*vendor = simple_strtol(s, NULL, 16);
273 
274 				s += 5;
275 				*device = simple_strtol(s, NULL, 16);
276 
277 				return 0;
278 			}
279 		}
280 		list += (len + 1);
281 	}
282 
283 	return -ENOENT;
284 }
285 
286 int fdtdec_get_pci_bar32(struct udevice *dev, struct fdt_pci_addr *addr,
287 			 u32 *bar)
288 {
289 	int barnum;
290 
291 	/* extract the bar number from fdt_pci_addr */
292 	barnum = addr->phys_hi & 0xff;
293 	if ((barnum < PCI_BASE_ADDRESS_0) || (barnum > PCI_CARDBUS_CIS))
294 		return -EINVAL;
295 
296 	barnum = (barnum - PCI_BASE_ADDRESS_0) / 4;
297 	*bar = dm_pci_read_bar32(dev, barnum);
298 
299 	return 0;
300 }
301 #endif
302 
303 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
304 		uint64_t default_val)
305 {
306 	const uint64_t *cell64;
307 	int length;
308 
309 	cell64 = fdt_getprop(blob, node, prop_name, &length);
310 	if (!cell64 || length < sizeof(*cell64))
311 		return default_val;
312 
313 	return fdt64_to_cpu(*cell64);
314 }
315 
316 int fdtdec_get_is_enabled(const void *blob, int node)
317 {
318 	const char *cell;
319 
320 	/*
321 	 * It should say "okay", so only allow that. Some fdts use "ok" but
322 	 * this is a bug. Please fix your device tree source file. See here
323 	 * for discussion:
324 	 *
325 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
326 	 */
327 	cell = fdt_getprop(blob, node, "status", NULL);
328 	if (cell)
329 		return 0 == strcmp(cell, "okay");
330 	return 1;
331 }
332 
333 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
334 {
335 	enum fdt_compat_id id;
336 
337 	/* Search our drivers */
338 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
339 		if (0 == fdt_node_check_compatible(blob, node,
340 				compat_names[id]))
341 			return id;
342 	return COMPAT_UNKNOWN;
343 }
344 
345 int fdtdec_next_compatible(const void *blob, int node,
346 		enum fdt_compat_id id)
347 {
348 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
349 }
350 
351 int fdtdec_next_compatible_subnode(const void *blob, int node,
352 		enum fdt_compat_id id, int *depthp)
353 {
354 	do {
355 		node = fdt_next_node(blob, node, depthp);
356 	} while (*depthp > 1);
357 
358 	/* If this is a direct subnode, and compatible, return it */
359 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
360 						blob, node, compat_names[id]))
361 		return node;
362 
363 	return -FDT_ERR_NOTFOUND;
364 }
365 
366 int fdtdec_next_alias(const void *blob, const char *name,
367 		enum fdt_compat_id id, int *upto)
368 {
369 #define MAX_STR_LEN 20
370 	char str[MAX_STR_LEN + 20];
371 	int node, err;
372 
373 	/* snprintf() is not available */
374 	assert(strlen(name) < MAX_STR_LEN);
375 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
376 	node = fdt_path_offset(blob, str);
377 	if (node < 0)
378 		return node;
379 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
380 	if (err < 0)
381 		return err;
382 	if (err)
383 		return -FDT_ERR_NOTFOUND;
384 	(*upto)++;
385 	return node;
386 }
387 
388 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
389 			enum fdt_compat_id id, int *node_list, int maxcount)
390 {
391 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
392 
393 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
394 }
395 
396 /* TODO: Can we tighten this code up a little? */
397 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
398 			enum fdt_compat_id id, int *node_list, int maxcount)
399 {
400 	int name_len = strlen(name);
401 	int nodes[maxcount];
402 	int num_found = 0;
403 	int offset, node;
404 	int alias_node;
405 	int count;
406 	int i, j;
407 
408 	/* find the alias node if present */
409 	alias_node = fdt_path_offset(blob, "/aliases");
410 
411 	/*
412 	 * start with nothing, and we can assume that the root node can't
413 	 * match
414 	 */
415 	memset(nodes, '\0', sizeof(nodes));
416 
417 	/* First find all the compatible nodes */
418 	for (node = count = 0; node >= 0 && count < maxcount;) {
419 		node = fdtdec_next_compatible(blob, node, id);
420 		if (node >= 0)
421 			nodes[count++] = node;
422 	}
423 	if (node >= 0)
424 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
425 		       __func__, name);
426 
427 	/* Now find all the aliases */
428 	for (offset = fdt_first_property_offset(blob, alias_node);
429 			offset > 0;
430 			offset = fdt_next_property_offset(blob, offset)) {
431 		const struct fdt_property *prop;
432 		const char *path;
433 		int number;
434 		int found;
435 
436 		node = 0;
437 		prop = fdt_get_property_by_offset(blob, offset, NULL);
438 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
439 		if (prop->len && 0 == strncmp(path, name, name_len))
440 			node = fdt_path_offset(blob, prop->data);
441 		if (node <= 0)
442 			continue;
443 
444 		/* Get the alias number */
445 		number = simple_strtoul(path + name_len, NULL, 10);
446 		if (number < 0 || number >= maxcount) {
447 			debug("%s: warning: alias '%s' is out of range\n",
448 			       __func__, path);
449 			continue;
450 		}
451 
452 		/* Make sure the node we found is actually in our list! */
453 		found = -1;
454 		for (j = 0; j < count; j++)
455 			if (nodes[j] == node) {
456 				found = j;
457 				break;
458 			}
459 
460 		if (found == -1) {
461 			debug("%s: warning: alias '%s' points to a node "
462 				"'%s' that is missing or is not compatible "
463 				" with '%s'\n", __func__, path,
464 				fdt_get_name(blob, node, NULL),
465 			       compat_names[id]);
466 			continue;
467 		}
468 
469 		/*
470 		 * Add this node to our list in the right place, and mark
471 		 * it as done.
472 		 */
473 		if (fdtdec_get_is_enabled(blob, node)) {
474 			if (node_list[number]) {
475 				debug("%s: warning: alias '%s' requires that "
476 				      "a node be placed in the list in a "
477 				      "position which is already filled by "
478 				      "node '%s'\n", __func__, path,
479 				      fdt_get_name(blob, node, NULL));
480 				continue;
481 			}
482 			node_list[number] = node;
483 			if (number >= num_found)
484 				num_found = number + 1;
485 		}
486 		nodes[found] = 0;
487 	}
488 
489 	/* Add any nodes not mentioned by an alias */
490 	for (i = j = 0; i < maxcount; i++) {
491 		if (!node_list[i]) {
492 			for (; j < maxcount; j++)
493 				if (nodes[j] &&
494 					fdtdec_get_is_enabled(blob, nodes[j]))
495 					break;
496 
497 			/* Have we run out of nodes to add? */
498 			if (j == maxcount)
499 				break;
500 
501 			assert(!node_list[i]);
502 			node_list[i] = nodes[j++];
503 			if (i >= num_found)
504 				num_found = i + 1;
505 		}
506 	}
507 
508 	return num_found;
509 }
510 
511 int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
512 			 int *seqp)
513 {
514 	int base_len = strlen(base);
515 	const char *find_name;
516 	int find_namelen;
517 	int prop_offset;
518 	int aliases;
519 
520 	find_name = fdt_get_name(blob, offset, &find_namelen);
521 	debug("Looking for '%s' at %d, name %s\n", base, offset, find_name);
522 
523 	aliases = fdt_path_offset(blob, "/aliases");
524 	for (prop_offset = fdt_first_property_offset(blob, aliases);
525 	     prop_offset > 0;
526 	     prop_offset = fdt_next_property_offset(blob, prop_offset)) {
527 		const char *prop;
528 		const char *name;
529 		const char *slash;
530 		int len, val;
531 
532 		prop = fdt_getprop_by_offset(blob, prop_offset, &name, &len);
533 		debug("   - %s, %s\n", name, prop);
534 		if (len < find_namelen || *prop != '/' || prop[len - 1] ||
535 		    strncmp(name, base, base_len))
536 			continue;
537 
538 		slash = strrchr(prop, '/');
539 		if (strcmp(slash + 1, find_name))
540 			continue;
541 		val = trailing_strtol(name);
542 		if (val != -1) {
543 			*seqp = val;
544 			debug("Found seq %d\n", *seqp);
545 			return 0;
546 		}
547 	}
548 
549 	debug("Not found\n");
550 	return -ENOENT;
551 }
552 
553 const char *fdtdec_get_chosen_prop(const void *blob, const char *name)
554 {
555 	int chosen_node;
556 
557 	if (!blob)
558 		return NULL;
559 	chosen_node = fdt_path_offset(blob, "/chosen");
560 	return fdt_getprop(blob, chosen_node, name, NULL);
561 }
562 
563 int fdtdec_get_chosen_node(const void *blob, const char *name)
564 {
565 	const char *prop;
566 
567 	prop = fdtdec_get_chosen_prop(blob, name);
568 	if (!prop)
569 		return -FDT_ERR_NOTFOUND;
570 	return fdt_path_offset(blob, prop);
571 }
572 
573 int fdtdec_check_fdt(void)
574 {
575 	/*
576 	 * We must have an FDT, but we cannot panic() yet since the console
577 	 * is not ready. So for now, just assert(). Boards which need an early
578 	 * FDT (prior to console ready) will need to make their own
579 	 * arrangements and do their own checks.
580 	 */
581 	assert(!fdtdec_prepare_fdt());
582 	return 0;
583 }
584 
585 /*
586  * This function is a little odd in that it accesses global data. At some
587  * point if the architecture board.c files merge this will make more sense.
588  * Even now, it is common code.
589  */
590 int fdtdec_prepare_fdt(void)
591 {
592 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
593 	    fdt_check_header(gd->fdt_blob)) {
594 #ifdef CONFIG_SPL_BUILD
595 		puts("Missing DTB\n");
596 #else
597 		puts("No valid device tree binary found - please append one to U-Boot binary, use u-boot-dtb.bin or define CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
598 # ifdef DEBUG
599 		if (gd->fdt_blob) {
600 			printf("fdt_blob=%p\n", gd->fdt_blob);
601 			print_buffer((ulong)gd->fdt_blob, gd->fdt_blob, 4,
602 				     32, 0);
603 		}
604 # endif
605 #endif
606 		return -1;
607 	}
608 	return 0;
609 }
610 
611 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
612 {
613 	const u32 *phandle;
614 	int lookup;
615 
616 	debug("%s: %s\n", __func__, prop_name);
617 	phandle = fdt_getprop(blob, node, prop_name, NULL);
618 	if (!phandle)
619 		return -FDT_ERR_NOTFOUND;
620 
621 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
622 	return lookup;
623 }
624 
625 /**
626  * Look up a property in a node and check that it has a minimum length.
627  *
628  * @param blob		FDT blob
629  * @param node		node to examine
630  * @param prop_name	name of property to find
631  * @param min_len	minimum property length in bytes
632  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
633 			found, or -FDT_ERR_BADLAYOUT if not enough data
634  * @return pointer to cell, which is only valid if err == 0
635  */
636 static const void *get_prop_check_min_len(const void *blob, int node,
637 		const char *prop_name, int min_len, int *err)
638 {
639 	const void *cell;
640 	int len;
641 
642 	debug("%s: %s\n", __func__, prop_name);
643 	cell = fdt_getprop(blob, node, prop_name, &len);
644 	if (!cell)
645 		*err = -FDT_ERR_NOTFOUND;
646 	else if (len < min_len)
647 		*err = -FDT_ERR_BADLAYOUT;
648 	else
649 		*err = 0;
650 	return cell;
651 }
652 
653 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
654 		u32 *array, int count)
655 {
656 	const u32 *cell;
657 	int i, err = 0;
658 
659 	debug("%s: %s\n", __func__, prop_name);
660 	cell = get_prop_check_min_len(blob, node, prop_name,
661 				      sizeof(u32) * count, &err);
662 	if (!err) {
663 		for (i = 0; i < count; i++)
664 			array[i] = fdt32_to_cpu(cell[i]);
665 	}
666 	return err;
667 }
668 
669 int fdtdec_get_int_array_count(const void *blob, int node,
670 			       const char *prop_name, u32 *array, int count)
671 {
672 	const u32 *cell;
673 	int len, elems;
674 	int i;
675 
676 	debug("%s: %s\n", __func__, prop_name);
677 	cell = fdt_getprop(blob, node, prop_name, &len);
678 	if (!cell)
679 		return -FDT_ERR_NOTFOUND;
680 	elems = len / sizeof(u32);
681 	if (count > elems)
682 		count = elems;
683 	for (i = 0; i < count; i++)
684 		array[i] = fdt32_to_cpu(cell[i]);
685 
686 	return count;
687 }
688 
689 const u32 *fdtdec_locate_array(const void *blob, int node,
690 			       const char *prop_name, int count)
691 {
692 	const u32 *cell;
693 	int err;
694 
695 	cell = get_prop_check_min_len(blob, node, prop_name,
696 				      sizeof(u32) * count, &err);
697 	return err ? NULL : cell;
698 }
699 
700 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
701 {
702 	const s32 *cell;
703 	int len;
704 
705 	debug("%s: %s\n", __func__, prop_name);
706 	cell = fdt_getprop(blob, node, prop_name, &len);
707 	return cell != NULL;
708 }
709 
710 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
711 				   const char *list_name,
712 				   const char *cells_name,
713 				   int cell_count, int index,
714 				   struct fdtdec_phandle_args *out_args)
715 {
716 	const __be32 *list, *list_end;
717 	int rc = 0, size, cur_index = 0;
718 	uint32_t count = 0;
719 	int node = -1;
720 	int phandle;
721 
722 	/* Retrieve the phandle list property */
723 	list = fdt_getprop(blob, src_node, list_name, &size);
724 	if (!list)
725 		return -ENOENT;
726 	list_end = list + size / sizeof(*list);
727 
728 	/* Loop over the phandles until all the requested entry is found */
729 	while (list < list_end) {
730 		rc = -EINVAL;
731 		count = 0;
732 
733 		/*
734 		 * If phandle is 0, then it is an empty entry with no
735 		 * arguments.  Skip forward to the next entry.
736 		 */
737 		phandle = be32_to_cpup(list++);
738 		if (phandle) {
739 			/*
740 			 * Find the provider node and parse the #*-cells
741 			 * property to determine the argument length.
742 			 *
743 			 * This is not needed if the cell count is hard-coded
744 			 * (i.e. cells_name not set, but cell_count is set),
745 			 * except when we're going to return the found node
746 			 * below.
747 			 */
748 			if (cells_name || cur_index == index) {
749 				node = fdt_node_offset_by_phandle(blob,
750 								  phandle);
751 				if (!node) {
752 					debug("%s: could not find phandle\n",
753 					      fdt_get_name(blob, src_node,
754 							   NULL));
755 					goto err;
756 				}
757 			}
758 
759 			if (cells_name) {
760 				count = fdtdec_get_int(blob, node, cells_name,
761 						       -1);
762 				if (count == -1) {
763 					debug("%s: could not get %s for %s\n",
764 					      fdt_get_name(blob, src_node,
765 							   NULL),
766 					      cells_name,
767 					      fdt_get_name(blob, node,
768 							   NULL));
769 					goto err;
770 				}
771 			} else {
772 				count = cell_count;
773 			}
774 
775 			/*
776 			 * Make sure that the arguments actually fit in the
777 			 * remaining property data length
778 			 */
779 			if (list + count > list_end) {
780 				debug("%s: arguments longer than property\n",
781 				      fdt_get_name(blob, src_node, NULL));
782 				goto err;
783 			}
784 		}
785 
786 		/*
787 		 * All of the error cases above bail out of the loop, so at
788 		 * this point, the parsing is successful. If the requested
789 		 * index matches, then fill the out_args structure and return,
790 		 * or return -ENOENT for an empty entry.
791 		 */
792 		rc = -ENOENT;
793 		if (cur_index == index) {
794 			if (!phandle)
795 				goto err;
796 
797 			if (out_args) {
798 				int i;
799 
800 				if (count > MAX_PHANDLE_ARGS) {
801 					debug("%s: too many arguments %d\n",
802 					      fdt_get_name(blob, src_node,
803 							   NULL), count);
804 					count = MAX_PHANDLE_ARGS;
805 				}
806 				out_args->node = node;
807 				out_args->args_count = count;
808 				for (i = 0; i < count; i++) {
809 					out_args->args[i] =
810 							be32_to_cpup(list++);
811 				}
812 			}
813 
814 			/* Found it! return success */
815 			return 0;
816 		}
817 
818 		node = -1;
819 		list += count;
820 		cur_index++;
821 	}
822 
823 	/*
824 	 * Result will be one of:
825 	 * -ENOENT : index is for empty phandle
826 	 * -EINVAL : parsing error on data
827 	 * [1..n]  : Number of phandle (count mode; when index = -1)
828 	 */
829 	rc = index < 0 ? cur_index : -ENOENT;
830  err:
831 	return rc;
832 }
833 
834 int fdtdec_get_child_count(const void *blob, int node)
835 {
836 	int subnode;
837 	int num = 0;
838 
839 	fdt_for_each_subnode(subnode, blob, node)
840 		num++;
841 
842 	return num;
843 }
844 
845 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
846 		u8 *array, int count)
847 {
848 	const u8 *cell;
849 	int err;
850 
851 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
852 	if (!err)
853 		memcpy(array, cell, count);
854 	return err;
855 }
856 
857 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
858 			     const char *prop_name, int count)
859 {
860 	const u8 *cell;
861 	int err;
862 
863 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
864 	if (err)
865 		return NULL;
866 	return cell;
867 }
868 
869 int fdtdec_get_config_int(const void *blob, const char *prop_name,
870 		int default_val)
871 {
872 	int config_node;
873 
874 	debug("%s: %s\n", __func__, prop_name);
875 	config_node = fdt_path_offset(blob, "/config");
876 	if (config_node < 0)
877 		return default_val;
878 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
879 }
880 
881 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
882 {
883 	int config_node;
884 	const void *prop;
885 
886 	debug("%s: %s\n", __func__, prop_name);
887 	config_node = fdt_path_offset(blob, "/config");
888 	if (config_node < 0)
889 		return 0;
890 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
891 
892 	return prop != NULL;
893 }
894 
895 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
896 {
897 	const char *nodep;
898 	int nodeoffset;
899 	int len;
900 
901 	debug("%s: %s\n", __func__, prop_name);
902 	nodeoffset = fdt_path_offset(blob, "/config");
903 	if (nodeoffset < 0)
904 		return NULL;
905 
906 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
907 	if (!nodep)
908 		return NULL;
909 
910 	return (char *)nodep;
911 }
912 
913 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
914 			 fdt_addr_t *basep, fdt_size_t *sizep)
915 {
916 	const fdt_addr_t *cell;
917 	int len;
918 
919 	debug("%s: %s: %s\n", __func__, fdt_get_name(blob, node, NULL),
920 	      prop_name);
921 	cell = fdt_getprop(blob, node, prop_name, &len);
922 	if (!cell || (len < sizeof(fdt_addr_t) * 2)) {
923 		debug("cell=%p, len=%d\n", cell, len);
924 		return -1;
925 	}
926 
927 	*basep = fdt_addr_to_cpu(*cell);
928 	*sizep = fdt_size_to_cpu(cell[1]);
929 	debug("%s: base=%08lx, size=%lx\n", __func__, (ulong)*basep,
930 	      (ulong)*sizep);
931 
932 	return 0;
933 }
934 
935 /**
936  * Read a flash entry from the fdt
937  *
938  * @param blob		FDT blob
939  * @param node		Offset of node to read
940  * @param name		Name of node being read
941  * @param entry		Place to put offset and size of this node
942  * @return 0 if ok, -ve on error
943  */
944 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
945 			   struct fmap_entry *entry)
946 {
947 	const char *prop;
948 	u32 reg[2];
949 
950 	if (fdtdec_get_int_array(blob, node, "reg", reg, 2)) {
951 		debug("Node '%s' has bad/missing 'reg' property\n", name);
952 		return -FDT_ERR_NOTFOUND;
953 	}
954 	entry->offset = reg[0];
955 	entry->length = reg[1];
956 	entry->used = fdtdec_get_int(blob, node, "used", entry->length);
957 	prop = fdt_getprop(blob, node, "compress", NULL);
958 	entry->compress_algo = prop && !strcmp(prop, "lzo") ?
959 		FMAP_COMPRESS_LZO : FMAP_COMPRESS_NONE;
960 	prop = fdt_getprop(blob, node, "hash", &entry->hash_size);
961 	entry->hash_algo = prop ? FMAP_HASH_SHA256 : FMAP_HASH_NONE;
962 	entry->hash = (uint8_t *)prop;
963 
964 	return 0;
965 }
966 
967 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells)
968 {
969 	u64 number = 0;
970 
971 	while (cells--)
972 		number = (number << 32) | fdt32_to_cpu(*ptr++);
973 
974 	return number;
975 }
976 
977 int fdt_get_resource(const void *fdt, int node, const char *property,
978 		     unsigned int index, struct fdt_resource *res)
979 {
980 	const fdt32_t *ptr, *end;
981 	int na, ns, len, parent;
982 	unsigned int i = 0;
983 
984 	parent = fdt_parent_offset(fdt, node);
985 	if (parent < 0)
986 		return parent;
987 
988 	na = fdt_address_cells(fdt, parent);
989 	ns = fdt_size_cells(fdt, parent);
990 
991 	ptr = fdt_getprop(fdt, node, property, &len);
992 	if (!ptr)
993 		return len;
994 
995 	end = ptr + len / sizeof(*ptr);
996 
997 	while (ptr + na + ns <= end) {
998 		if (i == index) {
999 			res->start = res->end = fdtdec_get_number(ptr, na);
1000 			res->end += fdtdec_get_number(&ptr[na], ns) - 1;
1001 			return 0;
1002 		}
1003 
1004 		ptr += na + ns;
1005 		i++;
1006 	}
1007 
1008 	return -FDT_ERR_NOTFOUND;
1009 }
1010 
1011 int fdt_get_named_resource(const void *fdt, int node, const char *property,
1012 			   const char *prop_names, const char *name,
1013 			   struct fdt_resource *res)
1014 {
1015 	int index;
1016 
1017 	index = fdt_stringlist_search(fdt, node, prop_names, name);
1018 	if (index < 0)
1019 		return index;
1020 
1021 	return fdt_get_resource(fdt, node, property, index, res);
1022 }
1023 
1024 int fdtdec_decode_memory_region(const void *blob, int config_node,
1025 				const char *mem_type, const char *suffix,
1026 				fdt_addr_t *basep, fdt_size_t *sizep)
1027 {
1028 	char prop_name[50];
1029 	const char *mem;
1030 	fdt_size_t size, offset_size;
1031 	fdt_addr_t base, offset;
1032 	int node;
1033 
1034 	if (config_node == -1) {
1035 		config_node = fdt_path_offset(blob, "/config");
1036 		if (config_node < 0) {
1037 			debug("%s: Cannot find /config node\n", __func__);
1038 			return -ENOENT;
1039 		}
1040 	}
1041 	if (!suffix)
1042 		suffix = "";
1043 
1044 	snprintf(prop_name, sizeof(prop_name), "%s-memory%s", mem_type,
1045 		 suffix);
1046 	mem = fdt_getprop(blob, config_node, prop_name, NULL);
1047 	if (!mem) {
1048 		debug("%s: No memory type for '%s', using /memory\n", __func__,
1049 		      prop_name);
1050 		mem = "/memory";
1051 	}
1052 
1053 	node = fdt_path_offset(blob, mem);
1054 	if (node < 0) {
1055 		debug("%s: Failed to find node '%s': %s\n", __func__, mem,
1056 		      fdt_strerror(node));
1057 		return -ENOENT;
1058 	}
1059 
1060 	/*
1061 	 * Not strictly correct - the memory may have multiple banks. We just
1062 	 * use the first
1063 	 */
1064 	if (fdtdec_decode_region(blob, node, "reg", &base, &size)) {
1065 		debug("%s: Failed to decode memory region %s\n", __func__,
1066 		      mem);
1067 		return -EINVAL;
1068 	}
1069 
1070 	snprintf(prop_name, sizeof(prop_name), "%s-offset%s", mem_type,
1071 		 suffix);
1072 	if (fdtdec_decode_region(blob, config_node, prop_name, &offset,
1073 				 &offset_size)) {
1074 		debug("%s: Failed to decode memory region '%s'\n", __func__,
1075 		      prop_name);
1076 		return -EINVAL;
1077 	}
1078 
1079 	*basep = base + offset;
1080 	*sizep = offset_size;
1081 
1082 	return 0;
1083 }
1084 
1085 static int decode_timing_property(const void *blob, int node, const char *name,
1086 				  struct timing_entry *result)
1087 {
1088 	int length, ret = 0;
1089 	const u32 *prop;
1090 
1091 	prop = fdt_getprop(blob, node, name, &length);
1092 	if (!prop) {
1093 		debug("%s: could not find property %s\n",
1094 		      fdt_get_name(blob, node, NULL), name);
1095 		return length;
1096 	}
1097 
1098 	if (length == sizeof(u32)) {
1099 		result->typ = fdtdec_get_int(blob, node, name, 0);
1100 		result->min = result->typ;
1101 		result->max = result->typ;
1102 	} else {
1103 		ret = fdtdec_get_int_array(blob, node, name, &result->min, 3);
1104 	}
1105 
1106 	return ret;
1107 }
1108 
1109 int fdtdec_decode_display_timing(const void *blob, int parent, int index,
1110 				 struct display_timing *dt)
1111 {
1112 	int i, node, timings_node;
1113 	u32 val = 0;
1114 	int ret = 0;
1115 
1116 	timings_node = fdt_subnode_offset(blob, parent, "display-timings");
1117 	if (timings_node < 0)
1118 		return timings_node;
1119 
1120 	for (i = 0, node = fdt_first_subnode(blob, timings_node);
1121 	     node > 0 && i != index;
1122 	     node = fdt_next_subnode(blob, node))
1123 		i++;
1124 
1125 	if (node < 0)
1126 		return node;
1127 
1128 	memset(dt, 0, sizeof(*dt));
1129 
1130 	ret |= decode_timing_property(blob, node, "hback-porch",
1131 				      &dt->hback_porch);
1132 	ret |= decode_timing_property(blob, node, "hfront-porch",
1133 				      &dt->hfront_porch);
1134 	ret |= decode_timing_property(blob, node, "hactive", &dt->hactive);
1135 	ret |= decode_timing_property(blob, node, "hsync-len", &dt->hsync_len);
1136 	ret |= decode_timing_property(blob, node, "vback-porch",
1137 				      &dt->vback_porch);
1138 	ret |= decode_timing_property(blob, node, "vfront-porch",
1139 				      &dt->vfront_porch);
1140 	ret |= decode_timing_property(blob, node, "vactive", &dt->vactive);
1141 	ret |= decode_timing_property(blob, node, "vsync-len", &dt->vsync_len);
1142 	ret |= decode_timing_property(blob, node, "clock-frequency",
1143 				      &dt->pixelclock);
1144 
1145 	dt->flags = 0;
1146 	val = fdtdec_get_int(blob, node, "vsync-active", -1);
1147 	if (val != -1) {
1148 		dt->flags |= val ? DISPLAY_FLAGS_VSYNC_HIGH :
1149 				DISPLAY_FLAGS_VSYNC_LOW;
1150 	}
1151 	val = fdtdec_get_int(blob, node, "hsync-active", -1);
1152 	if (val != -1) {
1153 		dt->flags |= val ? DISPLAY_FLAGS_HSYNC_HIGH :
1154 				DISPLAY_FLAGS_HSYNC_LOW;
1155 	}
1156 	val = fdtdec_get_int(blob, node, "de-active", -1);
1157 	if (val != -1) {
1158 		dt->flags |= val ? DISPLAY_FLAGS_DE_HIGH :
1159 				DISPLAY_FLAGS_DE_LOW;
1160 	}
1161 	val = fdtdec_get_int(blob, node, "pixelclk-active", -1);
1162 	if (val != -1) {
1163 		dt->flags |= val ? DISPLAY_FLAGS_PIXDATA_POSEDGE :
1164 				DISPLAY_FLAGS_PIXDATA_NEGEDGE;
1165 	}
1166 
1167 	if (fdtdec_get_bool(blob, node, "interlaced"))
1168 		dt->flags |= DISPLAY_FLAGS_INTERLACED;
1169 	if (fdtdec_get_bool(blob, node, "doublescan"))
1170 		dt->flags |= DISPLAY_FLAGS_DOUBLESCAN;
1171 	if (fdtdec_get_bool(blob, node, "doubleclk"))
1172 		dt->flags |= DISPLAY_FLAGS_DOUBLECLK;
1173 
1174 	return ret;
1175 }
1176 
1177 int fdtdec_setup_memory_size(void)
1178 {
1179 	int ret, mem;
1180 	struct fdt_resource res;
1181 
1182 	mem = fdt_path_offset(gd->fdt_blob, "/memory");
1183 	if (mem < 0) {
1184 		debug("%s: Missing /memory node\n", __func__);
1185 		return -EINVAL;
1186 	}
1187 
1188 	ret = fdt_get_resource(gd->fdt_blob, mem, "reg", 0, &res);
1189 	if (ret != 0) {
1190 		debug("%s: Unable to decode first memory bank\n", __func__);
1191 		return -EINVAL;
1192 	}
1193 
1194 	gd->ram_size = (phys_size_t)(res.end - res.start + 1);
1195 	debug("%s: Initial DRAM size %llx\n", __func__, (u64)gd->ram_size);
1196 
1197 	return 0;
1198 }
1199 
1200 #if defined(CONFIG_NR_DRAM_BANKS)
1201 int fdtdec_setup_memory_banksize(void)
1202 {
1203 	int bank, ret, mem;
1204 	struct fdt_resource res;
1205 
1206 	mem = fdt_path_offset(gd->fdt_blob, "/memory");
1207 	if (mem < 0) {
1208 		debug("%s: Missing /memory node\n", __func__);
1209 		return -EINVAL;
1210 	}
1211 
1212 	for (bank = 0; bank < CONFIG_NR_DRAM_BANKS; bank++) {
1213 		ret = fdt_get_resource(gd->fdt_blob, mem, "reg", bank, &res);
1214 		if (ret == -FDT_ERR_NOTFOUND)
1215 			break;
1216 		if (ret != 0)
1217 			return -EINVAL;
1218 
1219 		gd->bd->bi_dram[bank].start = (phys_addr_t)res.start;
1220 		gd->bd->bi_dram[bank].size =
1221 			(phys_size_t)(res.end - res.start + 1);
1222 
1223 		debug("%s: DRAM Bank #%d: start = 0x%llx, size = 0x%llx\n",
1224 		      __func__, bank,
1225 		      (unsigned long long)gd->bd->bi_dram[bank].start,
1226 		      (unsigned long long)gd->bd->bi_dram[bank].size);
1227 	}
1228 
1229 	return 0;
1230 }
1231 #endif
1232 
1233 int fdtdec_setup(void)
1234 {
1235 #if CONFIG_IS_ENABLED(OF_CONTROL)
1236 # ifdef CONFIG_OF_EMBED
1237 	/* Get a pointer to the FDT */
1238 	gd->fdt_blob = __dtb_dt_begin;
1239 # elif defined CONFIG_OF_SEPARATE
1240 #  ifdef CONFIG_SPL_BUILD
1241 	/* FDT is at end of BSS unless it is in a different memory region */
1242 	if (IS_ENABLED(CONFIG_SPL_SEPARATE_BSS))
1243 		gd->fdt_blob = (ulong *)&_image_binary_end;
1244 	else
1245 		gd->fdt_blob = (ulong *)&__bss_end;
1246 #  else
1247 	/* FDT is at end of image */
1248 	gd->fdt_blob = (ulong *)&_end;
1249 #  endif
1250 # elif defined(CONFIG_OF_HOSTFILE)
1251 	if (sandbox_read_fdt_from_file()) {
1252 		puts("Failed to read control FDT\n");
1253 		return -1;
1254 	}
1255 # endif
1256 # ifndef CONFIG_SPL_BUILD
1257 	/* Allow the early environment to override the fdt address */
1258 	gd->fdt_blob = (void *)getenv_ulong("fdtcontroladdr", 16,
1259 						(uintptr_t)gd->fdt_blob);
1260 # endif
1261 #endif
1262 	return fdtdec_prepare_fdt();
1263 }
1264 
1265 #endif /* !USE_HOSTCC */
1266