xref: /openbmc/u-boot/lib/fdtdec.c (revision 32df39c7)
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 DECLARE_GLOBAL_DATA_PTR;
15 
16 /*
17  * Here are the type we know about. One day we might allow drivers to
18  * register. For now we just put them here. The COMPAT macro allows us to
19  * turn this into a sparse list later, and keeps the ID with the name.
20  */
21 #define COMPAT(id, name) name
22 static const char * const compat_names[COMPAT_COUNT] = {
23 	COMPAT(UNKNOWN, "<none>"),
24 	COMPAT(NVIDIA_TEGRA20_USB, "nvidia,tegra20-ehci"),
25 	COMPAT(NVIDIA_TEGRA30_USB, "nvidia,tegra30-ehci"),
26 	COMPAT(NVIDIA_TEGRA114_USB, "nvidia,tegra114-ehci"),
27 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
28 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
29 	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
30 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
31 	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
32 	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
33 	COMPAT(NVIDIA_TEGRA124_SDMMC, "nvidia,tegra124-sdhci"),
34 	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
35 	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
36 	COMPAT(NVIDIA_TEGRA124_PCIE, "nvidia,tegra124-pcie"),
37 	COMPAT(NVIDIA_TEGRA30_PCIE, "nvidia,tegra30-pcie"),
38 	COMPAT(NVIDIA_TEGRA20_PCIE, "nvidia,tegra20-pcie"),
39 	COMPAT(NVIDIA_TEGRA124_XUSB_PADCTL, "nvidia,tegra124-xusb-padctl"),
40 	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
41 	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
42 	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
43 	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
44 	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
45 	COMPAT(GOOGLE_CROS_EC, "google,cros-ec"),
46 	COMPAT(GOOGLE_CROS_EC_KEYB, "google,cros-ec-keyb"),
47 	COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
48 	COMPAT(SAMSUNG_EXYNOS5_XHCI, "samsung,exynos5250-xhci"),
49 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
50 	COMPAT(SAMSUNG_EXYNOS5_USB3_PHY, "samsung,exynos5250-usb3-phy"),
51 	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
52 	COMPAT(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
53 	COMPAT(SAMSUNG_EXYNOS_MIPI_DSI, "samsung,exynos-mipi-dsi"),
54 	COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
55 	COMPAT(SAMSUNG_EXYNOS_DWMMC, "samsung,exynos-dwmmc"),
56 	COMPAT(SAMSUNG_EXYNOS_MMC, "samsung,exynos-mmc"),
57 	COMPAT(SAMSUNG_EXYNOS_SERIAL, "samsung,exynos4210-uart"),
58 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
59 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
60 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
61 	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
62 	COMPAT(INFINEON_SLB9645_TPM, "infineon,slb9645-tpm"),
63 	COMPAT(SAMSUNG_EXYNOS5_I2C, "samsung,exynos5-hsi2c"),
64 	COMPAT(SANDBOX_HOST_EMULATION, "sandbox,host-emulation"),
65 	COMPAT(SANDBOX_LCD_SDL, "sandbox,lcd-sdl"),
66 	COMPAT(TI_TPS65090, "ti,tps65090"),
67 	COMPAT(COMPAT_NXP_PTN3460, "nxp,ptn3460"),
68 	COMPAT(SAMSUNG_EXYNOS_SYSMMU, "samsung,sysmmu-v3.3"),
69 	COMPAT(PARADE_PS8625, "parade,ps8625"),
70 	COMPAT(COMPAT_INTEL_LPC, "intel,lpc"),
71 	COMPAT(INTEL_MICROCODE, "intel,microcode"),
72 	COMPAT(MEMORY_SPD, "memory-spd"),
73 	COMPAT(INTEL_PANTHERPOINT_AHCI, "intel,pantherpoint-ahci"),
74 	COMPAT(INTEL_MODEL_206AX, "intel,model-206ax"),
75 	COMPAT(INTEL_GMA, "intel,gma"),
76 	COMPAT(AMS_AS3722, "ams,as3722"),
77 	COMPAT(INTEL_ICH_SPI, "intel,ich-spi"),
78 	COMPAT(INTEL_QRK_MRC, "intel,quark-mrc"),
79 };
80 
81 const char *fdtdec_get_compatible(enum fdt_compat_id id)
82 {
83 	/* We allow reading of the 'unknown' ID for testing purposes */
84 	assert(id >= 0 && id < COMPAT_COUNT);
85 	return compat_names[id];
86 }
87 
88 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
89 		const char *prop_name, fdt_size_t *sizep)
90 {
91 	const fdt_addr_t *cell;
92 	int len;
93 
94 	debug("%s: %s: ", __func__, prop_name);
95 	cell = fdt_getprop(blob, node, prop_name, &len);
96 	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
97 		     len == sizeof(fdt_addr_t) * 2)) {
98 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
99 		if (sizep) {
100 			const fdt_size_t *size;
101 
102 			size = (fdt_size_t *)((char *)cell +
103 					sizeof(fdt_addr_t));
104 			*sizep = fdt_size_to_cpu(*size);
105 			debug("addr=%08lx, size=%08x\n",
106 			      (ulong)addr, *sizep);
107 		} else {
108 			debug("%08lx\n", (ulong)addr);
109 		}
110 		return addr;
111 	}
112 	debug("(not found)\n");
113 	return FDT_ADDR_T_NONE;
114 }
115 
116 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
117 		const char *prop_name)
118 {
119 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
120 }
121 
122 #ifdef CONFIG_PCI
123 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
124 		const char *prop_name, struct fdt_pci_addr *addr)
125 {
126 	const u32 *cell;
127 	int len;
128 	int ret = -ENOENT;
129 
130 	debug("%s: %s: ", __func__, prop_name);
131 
132 	/*
133 	 * If we follow the pci bus bindings strictly, we should check
134 	 * the value of the node's parent node's #address-cells and
135 	 * #size-cells. They need to be 3 and 2 accordingly. However,
136 	 * for simplicity we skip the check here.
137 	 */
138 	cell = fdt_getprop(blob, node, prop_name, &len);
139 	if (!cell)
140 		goto fail;
141 
142 	if ((len % FDT_PCI_REG_SIZE) == 0) {
143 		int num = len / FDT_PCI_REG_SIZE;
144 		int i;
145 
146 		for (i = 0; i < num; i++) {
147 			debug("pci address #%d: %08lx %08lx %08lx\n", i,
148 			      (ulong)fdt_addr_to_cpu(cell[0]),
149 			      (ulong)fdt_addr_to_cpu(cell[1]),
150 			      (ulong)fdt_addr_to_cpu(cell[2]));
151 			if ((fdt_addr_to_cpu(*cell) & type) == type) {
152 				addr->phys_hi = fdt_addr_to_cpu(cell[0]);
153 				addr->phys_mid = fdt_addr_to_cpu(cell[1]);
154 				addr->phys_lo = fdt_addr_to_cpu(cell[2]);
155 				break;
156 			} else {
157 				cell += (FDT_PCI_ADDR_CELLS +
158 					 FDT_PCI_SIZE_CELLS);
159 			}
160 		}
161 
162 		if (i == num)
163 			goto fail;
164 
165 		return 0;
166 	} else {
167 		ret = -EINVAL;
168 	}
169 
170 fail:
171 	debug("(not found)\n");
172 	return ret;
173 }
174 
175 int fdtdec_get_pci_vendev(const void *blob, int node, u16 *vendor, u16 *device)
176 {
177 	const char *list, *end;
178 	int len;
179 
180 	list = fdt_getprop(blob, node, "compatible", &len);
181 	if (!list)
182 		return -ENOENT;
183 
184 	end = list + len;
185 	while (list < end) {
186 		char *s;
187 
188 		len = strlen(list);
189 		if (len >= strlen("pciVVVV,DDDD")) {
190 			s = strstr(list, "pci");
191 
192 			/*
193 			 * check if the string is something like pciVVVV,DDDD.RR
194 			 * or just pciVVVV,DDDD
195 			 */
196 			if (s && s[7] == ',' &&
197 			    (s[12] == '.' || s[12] == 0)) {
198 				s += 3;
199 				*vendor = simple_strtol(s, NULL, 16);
200 
201 				s += 5;
202 				*device = simple_strtol(s, NULL, 16);
203 
204 				return 0;
205 			}
206 		} else {
207 			list += (len + 1);
208 		}
209 	}
210 
211 	return -ENOENT;
212 }
213 
214 int fdtdec_get_pci_bdf(const void *blob, int node,
215 		struct fdt_pci_addr *addr, pci_dev_t *bdf)
216 {
217 	u16 dt_vendor, dt_device, vendor, device;
218 	int ret;
219 
220 	/* get vendor id & device id from the compatible string */
221 	ret = fdtdec_get_pci_vendev(blob, node, &dt_vendor, &dt_device);
222 	if (ret)
223 		return ret;
224 
225 	/* extract the bdf from fdt_pci_addr */
226 	*bdf = addr->phys_hi & 0xffff00;
227 
228 	/* read vendor id & device id based on bdf */
229 	pci_read_config_word(*bdf, PCI_VENDOR_ID, &vendor);
230 	pci_read_config_word(*bdf, PCI_DEVICE_ID, &device);
231 
232 	/*
233 	 * Note there are two places in the device tree to fully describe
234 	 * a pci device: one is via compatible string with a format of
235 	 * "pciVVVV,DDDD" and the other one is the bdf numbers encoded in
236 	 * the device node's reg address property. We read the vendor id
237 	 * and device id based on bdf and compare the values with the
238 	 * "VVVV,DDDD". If they are the same, then we are good to use bdf
239 	 * to read device's bar. But if they are different, we have to rely
240 	 * on the vendor id and device id extracted from the compatible
241 	 * string and locate the real bdf by pci_find_device(). This is
242 	 * because normally we may only know device's device number and
243 	 * function number when writing device tree. The bus number is
244 	 * dynamically assigned during the pci enumeration process.
245 	 */
246 	if ((dt_vendor != vendor) || (dt_device != device)) {
247 		*bdf = pci_find_device(dt_vendor, dt_device, 0);
248 		if (*bdf == -1)
249 			return -ENODEV;
250 	}
251 
252 	return 0;
253 }
254 
255 int fdtdec_get_pci_bar32(const void *blob, int node,
256 		struct fdt_pci_addr *addr, u32 *bar)
257 {
258 	pci_dev_t bdf;
259 	int barnum;
260 	int ret;
261 
262 	/* get pci devices's bdf */
263 	ret = fdtdec_get_pci_bdf(blob, node, addr, &bdf);
264 	if (ret)
265 		return ret;
266 
267 	/* extract the bar number from fdt_pci_addr */
268 	barnum = addr->phys_hi & 0xff;
269 	if ((barnum < PCI_BASE_ADDRESS_0) || (barnum > PCI_CARDBUS_CIS))
270 		return -EINVAL;
271 
272 	barnum = (barnum - PCI_BASE_ADDRESS_0) / 4;
273 	*bar = pci_read_bar32(pci_bus_to_hose(PCI_BUS(bdf)), bdf, barnum);
274 
275 	return 0;
276 }
277 #endif
278 
279 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
280 		uint64_t default_val)
281 {
282 	const uint64_t *cell64;
283 	int length;
284 
285 	cell64 = fdt_getprop(blob, node, prop_name, &length);
286 	if (!cell64 || length < sizeof(*cell64))
287 		return default_val;
288 
289 	return fdt64_to_cpu(*cell64);
290 }
291 
292 int fdtdec_get_is_enabled(const void *blob, int node)
293 {
294 	const char *cell;
295 
296 	/*
297 	 * It should say "okay", so only allow that. Some fdts use "ok" but
298 	 * this is a bug. Please fix your device tree source file. See here
299 	 * for discussion:
300 	 *
301 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
302 	 */
303 	cell = fdt_getprop(blob, node, "status", NULL);
304 	if (cell)
305 		return 0 == strcmp(cell, "okay");
306 	return 1;
307 }
308 
309 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
310 {
311 	enum fdt_compat_id id;
312 
313 	/* Search our drivers */
314 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
315 		if (0 == fdt_node_check_compatible(blob, node,
316 				compat_names[id]))
317 			return id;
318 	return COMPAT_UNKNOWN;
319 }
320 
321 int fdtdec_next_compatible(const void *blob, int node,
322 		enum fdt_compat_id id)
323 {
324 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
325 }
326 
327 int fdtdec_next_compatible_subnode(const void *blob, int node,
328 		enum fdt_compat_id id, int *depthp)
329 {
330 	do {
331 		node = fdt_next_node(blob, node, depthp);
332 	} while (*depthp > 1);
333 
334 	/* If this is a direct subnode, and compatible, return it */
335 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
336 						blob, node, compat_names[id]))
337 		return node;
338 
339 	return -FDT_ERR_NOTFOUND;
340 }
341 
342 int fdtdec_next_alias(const void *blob, const char *name,
343 		enum fdt_compat_id id, int *upto)
344 {
345 #define MAX_STR_LEN 20
346 	char str[MAX_STR_LEN + 20];
347 	int node, err;
348 
349 	/* snprintf() is not available */
350 	assert(strlen(name) < MAX_STR_LEN);
351 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
352 	node = fdt_path_offset(blob, str);
353 	if (node < 0)
354 		return node;
355 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
356 	if (err < 0)
357 		return err;
358 	if (err)
359 		return -FDT_ERR_NOTFOUND;
360 	(*upto)++;
361 	return node;
362 }
363 
364 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
365 			enum fdt_compat_id id, int *node_list, int maxcount)
366 {
367 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
368 
369 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
370 }
371 
372 /* TODO: Can we tighten this code up a little? */
373 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
374 			enum fdt_compat_id id, int *node_list, int maxcount)
375 {
376 	int name_len = strlen(name);
377 	int nodes[maxcount];
378 	int num_found = 0;
379 	int offset, node;
380 	int alias_node;
381 	int count;
382 	int i, j;
383 
384 	/* find the alias node if present */
385 	alias_node = fdt_path_offset(blob, "/aliases");
386 
387 	/*
388 	 * start with nothing, and we can assume that the root node can't
389 	 * match
390 	 */
391 	memset(nodes, '\0', sizeof(nodes));
392 
393 	/* First find all the compatible nodes */
394 	for (node = count = 0; node >= 0 && count < maxcount;) {
395 		node = fdtdec_next_compatible(blob, node, id);
396 		if (node >= 0)
397 			nodes[count++] = node;
398 	}
399 	if (node >= 0)
400 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
401 		       __func__, name);
402 
403 	/* Now find all the aliases */
404 	for (offset = fdt_first_property_offset(blob, alias_node);
405 			offset > 0;
406 			offset = fdt_next_property_offset(blob, offset)) {
407 		const struct fdt_property *prop;
408 		const char *path;
409 		int number;
410 		int found;
411 
412 		node = 0;
413 		prop = fdt_get_property_by_offset(blob, offset, NULL);
414 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
415 		if (prop->len && 0 == strncmp(path, name, name_len))
416 			node = fdt_path_offset(blob, prop->data);
417 		if (node <= 0)
418 			continue;
419 
420 		/* Get the alias number */
421 		number = simple_strtoul(path + name_len, NULL, 10);
422 		if (number < 0 || number >= maxcount) {
423 			debug("%s: warning: alias '%s' is out of range\n",
424 			       __func__, path);
425 			continue;
426 		}
427 
428 		/* Make sure the node we found is actually in our list! */
429 		found = -1;
430 		for (j = 0; j < count; j++)
431 			if (nodes[j] == node) {
432 				found = j;
433 				break;
434 			}
435 
436 		if (found == -1) {
437 			debug("%s: warning: alias '%s' points to a node "
438 				"'%s' that is missing or is not compatible "
439 				" with '%s'\n", __func__, path,
440 				fdt_get_name(blob, node, NULL),
441 			       compat_names[id]);
442 			continue;
443 		}
444 
445 		/*
446 		 * Add this node to our list in the right place, and mark
447 		 * it as done.
448 		 */
449 		if (fdtdec_get_is_enabled(blob, node)) {
450 			if (node_list[number]) {
451 				debug("%s: warning: alias '%s' requires that "
452 				      "a node be placed in the list in a "
453 				      "position which is already filled by "
454 				      "node '%s'\n", __func__, path,
455 				      fdt_get_name(blob, node, NULL));
456 				continue;
457 			}
458 			node_list[number] = node;
459 			if (number >= num_found)
460 				num_found = number + 1;
461 		}
462 		nodes[found] = 0;
463 	}
464 
465 	/* Add any nodes not mentioned by an alias */
466 	for (i = j = 0; i < maxcount; i++) {
467 		if (!node_list[i]) {
468 			for (; j < maxcount; j++)
469 				if (nodes[j] &&
470 					fdtdec_get_is_enabled(blob, nodes[j]))
471 					break;
472 
473 			/* Have we run out of nodes to add? */
474 			if (j == maxcount)
475 				break;
476 
477 			assert(!node_list[i]);
478 			node_list[i] = nodes[j++];
479 			if (i >= num_found)
480 				num_found = i + 1;
481 		}
482 	}
483 
484 	return num_found;
485 }
486 
487 int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
488 			 int *seqp)
489 {
490 	int base_len = strlen(base);
491 	const char *find_name;
492 	int find_namelen;
493 	int prop_offset;
494 	int aliases;
495 
496 	find_name = fdt_get_name(blob, offset, &find_namelen);
497 	debug("Looking for '%s' at %d, name %s\n", base, offset, find_name);
498 
499 	aliases = fdt_path_offset(blob, "/aliases");
500 	for (prop_offset = fdt_first_property_offset(blob, aliases);
501 	     prop_offset > 0;
502 	     prop_offset = fdt_next_property_offset(blob, prop_offset)) {
503 		const char *prop;
504 		const char *name;
505 		const char *slash;
506 		const char *p;
507 		int len;
508 
509 		prop = fdt_getprop_by_offset(blob, prop_offset, &name, &len);
510 		debug("   - %s, %s\n", name, prop);
511 		if (len < find_namelen || *prop != '/' || prop[len - 1] ||
512 		    strncmp(name, base, base_len))
513 			continue;
514 
515 		slash = strrchr(prop, '/');
516 		if (strcmp(slash + 1, find_name))
517 			continue;
518 		for (p = name + strlen(name) - 1; p > name; p--) {
519 			if (!isdigit(*p)) {
520 				*seqp = simple_strtoul(p + 1, NULL, 10);
521 				debug("Found seq %d\n", *seqp);
522 				return 0;
523 			}
524 		}
525 	}
526 
527 	debug("Not found\n");
528 	return -ENOENT;
529 }
530 
531 int fdtdec_get_chosen_node(const void *blob, const char *name)
532 {
533 	const char *prop;
534 	int chosen_node;
535 	int len;
536 
537 	if (!blob)
538 		return -FDT_ERR_NOTFOUND;
539 	chosen_node = fdt_path_offset(blob, "/chosen");
540 	prop = fdt_getprop(blob, chosen_node, name, &len);
541 	if (!prop)
542 		return -FDT_ERR_NOTFOUND;
543 	return fdt_path_offset(blob, prop);
544 }
545 
546 int fdtdec_check_fdt(void)
547 {
548 	/*
549 	 * We must have an FDT, but we cannot panic() yet since the console
550 	 * is not ready. So for now, just assert(). Boards which need an early
551 	 * FDT (prior to console ready) will need to make their own
552 	 * arrangements and do their own checks.
553 	 */
554 	assert(!fdtdec_prepare_fdt());
555 	return 0;
556 }
557 
558 /*
559  * This function is a little odd in that it accesses global data. At some
560  * point if the architecture board.c files merge this will make more sense.
561  * Even now, it is common code.
562  */
563 int fdtdec_prepare_fdt(void)
564 {
565 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
566 	    fdt_check_header(gd->fdt_blob)) {
567 		printf("No valid FDT found - please append one to U-Boot "
568 			"binary, use u-boot-dtb.bin or define "
569 			"CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
570 		return -1;
571 	}
572 	return 0;
573 }
574 
575 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
576 {
577 	const u32 *phandle;
578 	int lookup;
579 
580 	debug("%s: %s\n", __func__, prop_name);
581 	phandle = fdt_getprop(blob, node, prop_name, NULL);
582 	if (!phandle)
583 		return -FDT_ERR_NOTFOUND;
584 
585 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
586 	return lookup;
587 }
588 
589 /**
590  * Look up a property in a node and check that it has a minimum length.
591  *
592  * @param blob		FDT blob
593  * @param node		node to examine
594  * @param prop_name	name of property to find
595  * @param min_len	minimum property length in bytes
596  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
597 			found, or -FDT_ERR_BADLAYOUT if not enough data
598  * @return pointer to cell, which is only valid if err == 0
599  */
600 static const void *get_prop_check_min_len(const void *blob, int node,
601 		const char *prop_name, int min_len, int *err)
602 {
603 	const void *cell;
604 	int len;
605 
606 	debug("%s: %s\n", __func__, prop_name);
607 	cell = fdt_getprop(blob, node, prop_name, &len);
608 	if (!cell)
609 		*err = -FDT_ERR_NOTFOUND;
610 	else if (len < min_len)
611 		*err = -FDT_ERR_BADLAYOUT;
612 	else
613 		*err = 0;
614 	return cell;
615 }
616 
617 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
618 		u32 *array, int count)
619 {
620 	const u32 *cell;
621 	int i, err = 0;
622 
623 	debug("%s: %s\n", __func__, prop_name);
624 	cell = get_prop_check_min_len(blob, node, prop_name,
625 				      sizeof(u32) * count, &err);
626 	if (!err) {
627 		for (i = 0; i < count; i++)
628 			array[i] = fdt32_to_cpu(cell[i]);
629 	}
630 	return err;
631 }
632 
633 int fdtdec_get_int_array_count(const void *blob, int node,
634 			       const char *prop_name, u32 *array, int count)
635 {
636 	const u32 *cell;
637 	int len, elems;
638 	int i;
639 
640 	debug("%s: %s\n", __func__, prop_name);
641 	cell = fdt_getprop(blob, node, prop_name, &len);
642 	if (!cell)
643 		return -FDT_ERR_NOTFOUND;
644 	elems = len / sizeof(u32);
645 	if (count > elems)
646 		count = elems;
647 	for (i = 0; i < count; i++)
648 		array[i] = fdt32_to_cpu(cell[i]);
649 
650 	return count;
651 }
652 
653 const u32 *fdtdec_locate_array(const void *blob, int node,
654 			       const char *prop_name, int count)
655 {
656 	const u32 *cell;
657 	int err;
658 
659 	cell = get_prop_check_min_len(blob, node, prop_name,
660 				      sizeof(u32) * count, &err);
661 	return err ? NULL : cell;
662 }
663 
664 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
665 {
666 	const s32 *cell;
667 	int len;
668 
669 	debug("%s: %s\n", __func__, prop_name);
670 	cell = fdt_getprop(blob, node, prop_name, &len);
671 	return cell != NULL;
672 }
673 
674 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
675 				   const char *list_name,
676 				   const char *cells_name,
677 				   int cell_count, int index,
678 				   struct fdtdec_phandle_args *out_args)
679 {
680 	const __be32 *list, *list_end;
681 	int rc = 0, size, cur_index = 0;
682 	uint32_t count = 0;
683 	int node = -1;
684 	int phandle;
685 
686 	/* Retrieve the phandle list property */
687 	list = fdt_getprop(blob, src_node, list_name, &size);
688 	if (!list)
689 		return -ENOENT;
690 	list_end = list + size / sizeof(*list);
691 
692 	/* Loop over the phandles until all the requested entry is found */
693 	while (list < list_end) {
694 		rc = -EINVAL;
695 		count = 0;
696 
697 		/*
698 		 * If phandle is 0, then it is an empty entry with no
699 		 * arguments.  Skip forward to the next entry.
700 		 */
701 		phandle = be32_to_cpup(list++);
702 		if (phandle) {
703 			/*
704 			 * Find the provider node and parse the #*-cells
705 			 * property to determine the argument length.
706 			 *
707 			 * This is not needed if the cell count is hard-coded
708 			 * (i.e. cells_name not set, but cell_count is set),
709 			 * except when we're going to return the found node
710 			 * below.
711 			 */
712 			if (cells_name || cur_index == index) {
713 				node = fdt_node_offset_by_phandle(blob,
714 								  phandle);
715 				if (!node) {
716 					debug("%s: could not find phandle\n",
717 					      fdt_get_name(blob, src_node,
718 							   NULL));
719 					goto err;
720 				}
721 			}
722 
723 			if (cells_name) {
724 				count = fdtdec_get_int(blob, node, cells_name,
725 						       -1);
726 				if (count == -1) {
727 					debug("%s: could not get %s for %s\n",
728 					      fdt_get_name(blob, src_node,
729 							   NULL),
730 					      cells_name,
731 					      fdt_get_name(blob, node,
732 							   NULL));
733 					goto err;
734 				}
735 			} else {
736 				count = cell_count;
737 			}
738 
739 			/*
740 			 * Make sure that the arguments actually fit in the
741 			 * remaining property data length
742 			 */
743 			if (list + count > list_end) {
744 				debug("%s: arguments longer than property\n",
745 				      fdt_get_name(blob, src_node, NULL));
746 				goto err;
747 			}
748 		}
749 
750 		/*
751 		 * All of the error cases above bail out of the loop, so at
752 		 * this point, the parsing is successful. If the requested
753 		 * index matches, then fill the out_args structure and return,
754 		 * or return -ENOENT for an empty entry.
755 		 */
756 		rc = -ENOENT;
757 		if (cur_index == index) {
758 			if (!phandle)
759 				goto err;
760 
761 			if (out_args) {
762 				int i;
763 
764 				if (count > MAX_PHANDLE_ARGS) {
765 					debug("%s: too many arguments %d\n",
766 					      fdt_get_name(blob, src_node,
767 							   NULL), count);
768 					count = MAX_PHANDLE_ARGS;
769 				}
770 				out_args->node = node;
771 				out_args->args_count = count;
772 				for (i = 0; i < count; i++) {
773 					out_args->args[i] =
774 							be32_to_cpup(list++);
775 				}
776 			}
777 
778 			/* Found it! return success */
779 			return 0;
780 		}
781 
782 		node = -1;
783 		list += count;
784 		cur_index++;
785 	}
786 
787 	/*
788 	 * Result will be one of:
789 	 * -ENOENT : index is for empty phandle
790 	 * -EINVAL : parsing error on data
791 	 * [1..n]  : Number of phandle (count mode; when index = -1)
792 	 */
793 	rc = index < 0 ? cur_index : -ENOENT;
794  err:
795 	return rc;
796 }
797 
798 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
799 		u8 *array, int count)
800 {
801 	const u8 *cell;
802 	int err;
803 
804 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
805 	if (!err)
806 		memcpy(array, cell, count);
807 	return err;
808 }
809 
810 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
811 			     const char *prop_name, int count)
812 {
813 	const u8 *cell;
814 	int err;
815 
816 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
817 	if (err)
818 		return NULL;
819 	return cell;
820 }
821 
822 int fdtdec_get_config_int(const void *blob, const char *prop_name,
823 		int default_val)
824 {
825 	int config_node;
826 
827 	debug("%s: %s\n", __func__, prop_name);
828 	config_node = fdt_path_offset(blob, "/config");
829 	if (config_node < 0)
830 		return default_val;
831 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
832 }
833 
834 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
835 {
836 	int config_node;
837 	const void *prop;
838 
839 	debug("%s: %s\n", __func__, prop_name);
840 	config_node = fdt_path_offset(blob, "/config");
841 	if (config_node < 0)
842 		return 0;
843 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
844 
845 	return prop != NULL;
846 }
847 
848 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
849 {
850 	const char *nodep;
851 	int nodeoffset;
852 	int len;
853 
854 	debug("%s: %s\n", __func__, prop_name);
855 	nodeoffset = fdt_path_offset(blob, "/config");
856 	if (nodeoffset < 0)
857 		return NULL;
858 
859 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
860 	if (!nodep)
861 		return NULL;
862 
863 	return (char *)nodep;
864 }
865 
866 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
867 			 fdt_addr_t *basep, fdt_size_t *sizep)
868 {
869 	const fdt_addr_t *cell;
870 	int len;
871 
872 	debug("%s: %s: %s\n", __func__, fdt_get_name(blob, node, NULL),
873 	      prop_name);
874 	cell = fdt_getprop(blob, node, prop_name, &len);
875 	if (!cell || (len < sizeof(fdt_addr_t) * 2)) {
876 		debug("cell=%p, len=%d\n", cell, len);
877 		return -1;
878 	}
879 
880 	*basep = fdt_addr_to_cpu(*cell);
881 	*sizep = fdt_size_to_cpu(cell[1]);
882 	debug("%s: base=%08lx, size=%lx\n", __func__, (ulong)*basep,
883 	      (ulong)*sizep);
884 
885 	return 0;
886 }
887 
888 /**
889  * Read a flash entry from the fdt
890  *
891  * @param blob		FDT blob
892  * @param node		Offset of node to read
893  * @param name		Name of node being read
894  * @param entry		Place to put offset and size of this node
895  * @return 0 if ok, -ve on error
896  */
897 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
898 			   struct fmap_entry *entry)
899 {
900 	const char *prop;
901 	u32 reg[2];
902 
903 	if (fdtdec_get_int_array(blob, node, "reg", reg, 2)) {
904 		debug("Node '%s' has bad/missing 'reg' property\n", name);
905 		return -FDT_ERR_NOTFOUND;
906 	}
907 	entry->offset = reg[0];
908 	entry->length = reg[1];
909 	entry->used = fdtdec_get_int(blob, node, "used", entry->length);
910 	prop = fdt_getprop(blob, node, "compress", NULL);
911 	entry->compress_algo = prop && !strcmp(prop, "lzo") ?
912 		FMAP_COMPRESS_LZO : FMAP_COMPRESS_NONE;
913 	prop = fdt_getprop(blob, node, "hash", &entry->hash_size);
914 	entry->hash_algo = prop ? FMAP_HASH_SHA256 : FMAP_HASH_NONE;
915 	entry->hash = (uint8_t *)prop;
916 
917 	return 0;
918 }
919 
920 static u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells)
921 {
922 	u64 number = 0;
923 
924 	while (cells--)
925 		number = (number << 32) | fdt32_to_cpu(*ptr++);
926 
927 	return number;
928 }
929 
930 int fdt_get_resource(const void *fdt, int node, const char *property,
931 		     unsigned int index, struct fdt_resource *res)
932 {
933 	const fdt32_t *ptr, *end;
934 	int na, ns, len, parent;
935 	unsigned int i = 0;
936 
937 	parent = fdt_parent_offset(fdt, node);
938 	if (parent < 0)
939 		return parent;
940 
941 	na = fdt_address_cells(fdt, parent);
942 	ns = fdt_size_cells(fdt, parent);
943 
944 	ptr = fdt_getprop(fdt, node, property, &len);
945 	if (!ptr)
946 		return len;
947 
948 	end = ptr + len / sizeof(*ptr);
949 
950 	while (ptr + na + ns <= end) {
951 		if (i == index) {
952 			res->start = res->end = fdtdec_get_number(ptr, na);
953 			res->end += fdtdec_get_number(&ptr[na], ns) - 1;
954 			return 0;
955 		}
956 
957 		ptr += na + ns;
958 		i++;
959 	}
960 
961 	return -FDT_ERR_NOTFOUND;
962 }
963 
964 int fdt_get_named_resource(const void *fdt, int node, const char *property,
965 			   const char *prop_names, const char *name,
966 			   struct fdt_resource *res)
967 {
968 	int index;
969 
970 	index = fdt_find_string(fdt, node, prop_names, name);
971 	if (index < 0)
972 		return index;
973 
974 	return fdt_get_resource(fdt, node, property, index, res);
975 }
976 
977 int fdtdec_decode_memory_region(const void *blob, int config_node,
978 				const char *mem_type, const char *suffix,
979 				fdt_addr_t *basep, fdt_size_t *sizep)
980 {
981 	char prop_name[50];
982 	const char *mem;
983 	fdt_size_t size, offset_size;
984 	fdt_addr_t base, offset;
985 	int node;
986 
987 	if (config_node == -1) {
988 		config_node = fdt_path_offset(blob, "/config");
989 		if (config_node < 0) {
990 			debug("%s: Cannot find /config node\n", __func__);
991 			return -ENOENT;
992 		}
993 	}
994 	if (!suffix)
995 		suffix = "";
996 
997 	snprintf(prop_name, sizeof(prop_name), "%s-memory%s", mem_type,
998 		 suffix);
999 	mem = fdt_getprop(blob, config_node, prop_name, NULL);
1000 	if (!mem) {
1001 		debug("%s: No memory type for '%s', using /memory\n", __func__,
1002 		      prop_name);
1003 		mem = "/memory";
1004 	}
1005 
1006 	node = fdt_path_offset(blob, mem);
1007 	if (node < 0) {
1008 		debug("%s: Failed to find node '%s': %s\n", __func__, mem,
1009 		      fdt_strerror(node));
1010 		return -ENOENT;
1011 	}
1012 
1013 	/*
1014 	 * Not strictly correct - the memory may have multiple banks. We just
1015 	 * use the first
1016 	 */
1017 	if (fdtdec_decode_region(blob, node, "reg", &base, &size)) {
1018 		debug("%s: Failed to decode memory region %s\n", __func__,
1019 		      mem);
1020 		return -EINVAL;
1021 	}
1022 
1023 	snprintf(prop_name, sizeof(prop_name), "%s-offset%s", mem_type,
1024 		 suffix);
1025 	if (fdtdec_decode_region(blob, config_node, prop_name, &offset,
1026 				 &offset_size)) {
1027 		debug("%s: Failed to decode memory region '%s'\n", __func__,
1028 		      prop_name);
1029 		return -EINVAL;
1030 	}
1031 
1032 	*basep = base + offset;
1033 	*sizep = offset_size;
1034 
1035 	return 0;
1036 }
1037 #endif
1038