xref: /openbmc/u-boot/lib/fdtdec.c (revision 19268834)
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 <asm/sections.h>
13 #include <linux/ctype.h>
14 
15 DECLARE_GLOBAL_DATA_PTR;
16 
17 /*
18  * Here are the type we know about. One day we might allow drivers to
19  * register. For now we just put them here. The COMPAT macro allows us to
20  * turn this into a sparse list later, and keeps the ID with the name.
21  */
22 #define COMPAT(id, name) name
23 static const char * const compat_names[COMPAT_COUNT] = {
24 	COMPAT(UNKNOWN, "<none>"),
25 	COMPAT(NVIDIA_TEGRA20_USB, "nvidia,tegra20-ehci"),
26 	COMPAT(NVIDIA_TEGRA30_USB, "nvidia,tegra30-ehci"),
27 	COMPAT(NVIDIA_TEGRA114_USB, "nvidia,tegra114-ehci"),
28 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
29 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
30 	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
31 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
32 	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
33 	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
34 	COMPAT(NVIDIA_TEGRA124_SDMMC, "nvidia,tegra124-sdhci"),
35 	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
36 	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
37 	COMPAT(NVIDIA_TEGRA124_PCIE, "nvidia,tegra124-pcie"),
38 	COMPAT(NVIDIA_TEGRA30_PCIE, "nvidia,tegra30-pcie"),
39 	COMPAT(NVIDIA_TEGRA20_PCIE, "nvidia,tegra20-pcie"),
40 	COMPAT(NVIDIA_TEGRA124_XUSB_PADCTL, "nvidia,tegra124-xusb-padctl"),
41 	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
42 	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
43 	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
44 	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
45 	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
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_LCD_SDL, "sandbox,lcd-sdl"),
65 	COMPAT(TI_TPS65090, "ti,tps65090"),
66 	COMPAT(COMPAT_NXP_PTN3460, "nxp,ptn3460"),
67 	COMPAT(SAMSUNG_EXYNOS_SYSMMU, "samsung,sysmmu-v3.3"),
68 	COMPAT(PARADE_PS8625, "parade,ps8625"),
69 	COMPAT(INTEL_MICROCODE, "intel,microcode"),
70 	COMPAT(MEMORY_SPD, "memory-spd"),
71 	COMPAT(INTEL_PANTHERPOINT_AHCI, "intel,pantherpoint-ahci"),
72 	COMPAT(INTEL_MODEL_206AX, "intel,model-206ax"),
73 	COMPAT(INTEL_GMA, "intel,gma"),
74 	COMPAT(AMS_AS3722, "ams,as3722"),
75 	COMPAT(INTEL_ICH_SPI, "intel,ich-spi"),
76 	COMPAT(INTEL_QRK_MRC, "intel,quark-mrc"),
77 	COMPAT(SOCIONEXT_XHCI, "socionext,uniphier-xhci"),
78 	COMPAT(COMPAT_INTEL_PCH, "intel,bd82x6x"),
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 			ret = -ENXIO;
164 			goto fail;
165 		}
166 
167 		return 0;
168 	} else {
169 		ret = -EINVAL;
170 	}
171 
172 fail:
173 	debug("(not found)\n");
174 	return ret;
175 }
176 
177 int fdtdec_get_pci_vendev(const void *blob, int node, u16 *vendor, u16 *device)
178 {
179 	const char *list, *end;
180 	int len;
181 
182 	list = fdt_getprop(blob, node, "compatible", &len);
183 	if (!list)
184 		return -ENOENT;
185 
186 	end = list + len;
187 	while (list < end) {
188 		char *s;
189 
190 		len = strlen(list);
191 		if (len >= strlen("pciVVVV,DDDD")) {
192 			s = strstr(list, "pci");
193 
194 			/*
195 			 * check if the string is something like pciVVVV,DDDD.RR
196 			 * or just pciVVVV,DDDD
197 			 */
198 			if (s && s[7] == ',' &&
199 			    (s[12] == '.' || s[12] == 0)) {
200 				s += 3;
201 				*vendor = simple_strtol(s, NULL, 16);
202 
203 				s += 5;
204 				*device = simple_strtol(s, NULL, 16);
205 
206 				return 0;
207 			}
208 		} else {
209 			list += (len + 1);
210 		}
211 	}
212 
213 	return -ENOENT;
214 }
215 
216 int fdtdec_get_pci_bdf(const void *blob, int node,
217 		struct fdt_pci_addr *addr, pci_dev_t *bdf)
218 {
219 	u16 dt_vendor, dt_device, vendor, device;
220 	int ret;
221 
222 	/* get vendor id & device id from the compatible string */
223 	ret = fdtdec_get_pci_vendev(blob, node, &dt_vendor, &dt_device);
224 	if (ret)
225 		return ret;
226 
227 	/* extract the bdf from fdt_pci_addr */
228 	*bdf = addr->phys_hi & 0xffff00;
229 
230 	/* read vendor id & device id based on bdf */
231 	pci_read_config_word(*bdf, PCI_VENDOR_ID, &vendor);
232 	pci_read_config_word(*bdf, PCI_DEVICE_ID, &device);
233 
234 	/*
235 	 * Note there are two places in the device tree to fully describe
236 	 * a pci device: one is via compatible string with a format of
237 	 * "pciVVVV,DDDD" and the other one is the bdf numbers encoded in
238 	 * the device node's reg address property. We read the vendor id
239 	 * and device id based on bdf and compare the values with the
240 	 * "VVVV,DDDD". If they are the same, then we are good to use bdf
241 	 * to read device's bar. But if they are different, we have to rely
242 	 * on the vendor id and device id extracted from the compatible
243 	 * string and locate the real bdf by pci_find_device(). This is
244 	 * because normally we may only know device's device number and
245 	 * function number when writing device tree. The bus number is
246 	 * dynamically assigned during the pci enumeration process.
247 	 */
248 	if ((dt_vendor != vendor) || (dt_device != device)) {
249 		*bdf = pci_find_device(dt_vendor, dt_device, 0);
250 		if (*bdf == -1)
251 			return -ENODEV;
252 	}
253 
254 	return 0;
255 }
256 
257 int fdtdec_get_pci_bar32(const void *blob, int node,
258 		struct fdt_pci_addr *addr, u32 *bar)
259 {
260 	pci_dev_t bdf;
261 	int barnum;
262 	int ret;
263 
264 	/* get pci devices's bdf */
265 	ret = fdtdec_get_pci_bdf(blob, node, addr, &bdf);
266 	if (ret)
267 		return ret;
268 
269 	/* extract the bar number from fdt_pci_addr */
270 	barnum = addr->phys_hi & 0xff;
271 	if ((barnum < PCI_BASE_ADDRESS_0) || (barnum > PCI_CARDBUS_CIS))
272 		return -EINVAL;
273 
274 	barnum = (barnum - PCI_BASE_ADDRESS_0) / 4;
275 	*bar = pci_read_bar32(pci_bus_to_hose(PCI_BUS(bdf)), bdf, barnum);
276 
277 	return 0;
278 }
279 #endif
280 
281 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
282 		uint64_t default_val)
283 {
284 	const uint64_t *cell64;
285 	int length;
286 
287 	cell64 = fdt_getprop(blob, node, prop_name, &length);
288 	if (!cell64 || length < sizeof(*cell64))
289 		return default_val;
290 
291 	return fdt64_to_cpu(*cell64);
292 }
293 
294 int fdtdec_get_is_enabled(const void *blob, int node)
295 {
296 	const char *cell;
297 
298 	/*
299 	 * It should say "okay", so only allow that. Some fdts use "ok" but
300 	 * this is a bug. Please fix your device tree source file. See here
301 	 * for discussion:
302 	 *
303 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
304 	 */
305 	cell = fdt_getprop(blob, node, "status", NULL);
306 	if (cell)
307 		return 0 == strcmp(cell, "okay");
308 	return 1;
309 }
310 
311 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
312 {
313 	enum fdt_compat_id id;
314 
315 	/* Search our drivers */
316 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
317 		if (0 == fdt_node_check_compatible(blob, node,
318 				compat_names[id]))
319 			return id;
320 	return COMPAT_UNKNOWN;
321 }
322 
323 int fdtdec_next_compatible(const void *blob, int node,
324 		enum fdt_compat_id id)
325 {
326 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
327 }
328 
329 int fdtdec_next_compatible_subnode(const void *blob, int node,
330 		enum fdt_compat_id id, int *depthp)
331 {
332 	do {
333 		node = fdt_next_node(blob, node, depthp);
334 	} while (*depthp > 1);
335 
336 	/* If this is a direct subnode, and compatible, return it */
337 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
338 						blob, node, compat_names[id]))
339 		return node;
340 
341 	return -FDT_ERR_NOTFOUND;
342 }
343 
344 int fdtdec_next_alias(const void *blob, const char *name,
345 		enum fdt_compat_id id, int *upto)
346 {
347 #define MAX_STR_LEN 20
348 	char str[MAX_STR_LEN + 20];
349 	int node, err;
350 
351 	/* snprintf() is not available */
352 	assert(strlen(name) < MAX_STR_LEN);
353 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
354 	node = fdt_path_offset(blob, str);
355 	if (node < 0)
356 		return node;
357 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
358 	if (err < 0)
359 		return err;
360 	if (err)
361 		return -FDT_ERR_NOTFOUND;
362 	(*upto)++;
363 	return node;
364 }
365 
366 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
367 			enum fdt_compat_id id, int *node_list, int maxcount)
368 {
369 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
370 
371 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
372 }
373 
374 /* TODO: Can we tighten this code up a little? */
375 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
376 			enum fdt_compat_id id, int *node_list, int maxcount)
377 {
378 	int name_len = strlen(name);
379 	int nodes[maxcount];
380 	int num_found = 0;
381 	int offset, node;
382 	int alias_node;
383 	int count;
384 	int i, j;
385 
386 	/* find the alias node if present */
387 	alias_node = fdt_path_offset(blob, "/aliases");
388 
389 	/*
390 	 * start with nothing, and we can assume that the root node can't
391 	 * match
392 	 */
393 	memset(nodes, '\0', sizeof(nodes));
394 
395 	/* First find all the compatible nodes */
396 	for (node = count = 0; node >= 0 && count < maxcount;) {
397 		node = fdtdec_next_compatible(blob, node, id);
398 		if (node >= 0)
399 			nodes[count++] = node;
400 	}
401 	if (node >= 0)
402 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
403 		       __func__, name);
404 
405 	/* Now find all the aliases */
406 	for (offset = fdt_first_property_offset(blob, alias_node);
407 			offset > 0;
408 			offset = fdt_next_property_offset(blob, offset)) {
409 		const struct fdt_property *prop;
410 		const char *path;
411 		int number;
412 		int found;
413 
414 		node = 0;
415 		prop = fdt_get_property_by_offset(blob, offset, NULL);
416 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
417 		if (prop->len && 0 == strncmp(path, name, name_len))
418 			node = fdt_path_offset(blob, prop->data);
419 		if (node <= 0)
420 			continue;
421 
422 		/* Get the alias number */
423 		number = simple_strtoul(path + name_len, NULL, 10);
424 		if (number < 0 || number >= maxcount) {
425 			debug("%s: warning: alias '%s' is out of range\n",
426 			       __func__, path);
427 			continue;
428 		}
429 
430 		/* Make sure the node we found is actually in our list! */
431 		found = -1;
432 		for (j = 0; j < count; j++)
433 			if (nodes[j] == node) {
434 				found = j;
435 				break;
436 			}
437 
438 		if (found == -1) {
439 			debug("%s: warning: alias '%s' points to a node "
440 				"'%s' that is missing or is not compatible "
441 				" with '%s'\n", __func__, path,
442 				fdt_get_name(blob, node, NULL),
443 			       compat_names[id]);
444 			continue;
445 		}
446 
447 		/*
448 		 * Add this node to our list in the right place, and mark
449 		 * it as done.
450 		 */
451 		if (fdtdec_get_is_enabled(blob, node)) {
452 			if (node_list[number]) {
453 				debug("%s: warning: alias '%s' requires that "
454 				      "a node be placed in the list in a "
455 				      "position which is already filled by "
456 				      "node '%s'\n", __func__, path,
457 				      fdt_get_name(blob, node, NULL));
458 				continue;
459 			}
460 			node_list[number] = node;
461 			if (number >= num_found)
462 				num_found = number + 1;
463 		}
464 		nodes[found] = 0;
465 	}
466 
467 	/* Add any nodes not mentioned by an alias */
468 	for (i = j = 0; i < maxcount; i++) {
469 		if (!node_list[i]) {
470 			for (; j < maxcount; j++)
471 				if (nodes[j] &&
472 					fdtdec_get_is_enabled(blob, nodes[j]))
473 					break;
474 
475 			/* Have we run out of nodes to add? */
476 			if (j == maxcount)
477 				break;
478 
479 			assert(!node_list[i]);
480 			node_list[i] = nodes[j++];
481 			if (i >= num_found)
482 				num_found = i + 1;
483 		}
484 	}
485 
486 	return num_found;
487 }
488 
489 int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
490 			 int *seqp)
491 {
492 	int base_len = strlen(base);
493 	const char *find_name;
494 	int find_namelen;
495 	int prop_offset;
496 	int aliases;
497 
498 	find_name = fdt_get_name(blob, offset, &find_namelen);
499 	debug("Looking for '%s' at %d, name %s\n", base, offset, find_name);
500 
501 	aliases = fdt_path_offset(blob, "/aliases");
502 	for (prop_offset = fdt_first_property_offset(blob, aliases);
503 	     prop_offset > 0;
504 	     prop_offset = fdt_next_property_offset(blob, prop_offset)) {
505 		const char *prop;
506 		const char *name;
507 		const char *slash;
508 		const char *p;
509 		int len;
510 
511 		prop = fdt_getprop_by_offset(blob, prop_offset, &name, &len);
512 		debug("   - %s, %s\n", name, prop);
513 		if (len < find_namelen || *prop != '/' || prop[len - 1] ||
514 		    strncmp(name, base, base_len))
515 			continue;
516 
517 		slash = strrchr(prop, '/');
518 		if (strcmp(slash + 1, find_name))
519 			continue;
520 		for (p = name + strlen(name) - 1; p > name; p--) {
521 			if (!isdigit(*p)) {
522 				*seqp = simple_strtoul(p + 1, NULL, 10);
523 				debug("Found seq %d\n", *seqp);
524 				return 0;
525 			}
526 		}
527 	}
528 
529 	debug("Not found\n");
530 	return -ENOENT;
531 }
532 
533 int fdtdec_get_chosen_node(const void *blob, const char *name)
534 {
535 	const char *prop;
536 	int chosen_node;
537 	int len;
538 
539 	if (!blob)
540 		return -FDT_ERR_NOTFOUND;
541 	chosen_node = fdt_path_offset(blob, "/chosen");
542 	prop = fdt_getprop(blob, chosen_node, name, &len);
543 	if (!prop)
544 		return -FDT_ERR_NOTFOUND;
545 	return fdt_path_offset(blob, prop);
546 }
547 
548 int fdtdec_check_fdt(void)
549 {
550 	/*
551 	 * We must have an FDT, but we cannot panic() yet since the console
552 	 * is not ready. So for now, just assert(). Boards which need an early
553 	 * FDT (prior to console ready) will need to make their own
554 	 * arrangements and do their own checks.
555 	 */
556 	assert(!fdtdec_prepare_fdt());
557 	return 0;
558 }
559 
560 /*
561  * This function is a little odd in that it accesses global data. At some
562  * point if the architecture board.c files merge this will make more sense.
563  * Even now, it is common code.
564  */
565 int fdtdec_prepare_fdt(void)
566 {
567 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
568 	    fdt_check_header(gd->fdt_blob)) {
569 #ifdef CONFIG_SPL_BUILD
570 		puts("Missing DTB\n");
571 #else
572 		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");
573 #endif
574 		return -1;
575 	}
576 	return 0;
577 }
578 
579 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
580 {
581 	const u32 *phandle;
582 	int lookup;
583 
584 	debug("%s: %s\n", __func__, prop_name);
585 	phandle = fdt_getprop(blob, node, prop_name, NULL);
586 	if (!phandle)
587 		return -FDT_ERR_NOTFOUND;
588 
589 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
590 	return lookup;
591 }
592 
593 /**
594  * Look up a property in a node and check that it has a minimum length.
595  *
596  * @param blob		FDT blob
597  * @param node		node to examine
598  * @param prop_name	name of property to find
599  * @param min_len	minimum property length in bytes
600  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
601 			found, or -FDT_ERR_BADLAYOUT if not enough data
602  * @return pointer to cell, which is only valid if err == 0
603  */
604 static const void *get_prop_check_min_len(const void *blob, int node,
605 		const char *prop_name, int min_len, int *err)
606 {
607 	const void *cell;
608 	int len;
609 
610 	debug("%s: %s\n", __func__, prop_name);
611 	cell = fdt_getprop(blob, node, prop_name, &len);
612 	if (!cell)
613 		*err = -FDT_ERR_NOTFOUND;
614 	else if (len < min_len)
615 		*err = -FDT_ERR_BADLAYOUT;
616 	else
617 		*err = 0;
618 	return cell;
619 }
620 
621 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
622 		u32 *array, int count)
623 {
624 	const u32 *cell;
625 	int i, err = 0;
626 
627 	debug("%s: %s\n", __func__, prop_name);
628 	cell = get_prop_check_min_len(blob, node, prop_name,
629 				      sizeof(u32) * count, &err);
630 	if (!err) {
631 		for (i = 0; i < count; i++)
632 			array[i] = fdt32_to_cpu(cell[i]);
633 	}
634 	return err;
635 }
636 
637 int fdtdec_get_int_array_count(const void *blob, int node,
638 			       const char *prop_name, u32 *array, int count)
639 {
640 	const u32 *cell;
641 	int len, elems;
642 	int i;
643 
644 	debug("%s: %s\n", __func__, prop_name);
645 	cell = fdt_getprop(blob, node, prop_name, &len);
646 	if (!cell)
647 		return -FDT_ERR_NOTFOUND;
648 	elems = len / sizeof(u32);
649 	if (count > elems)
650 		count = elems;
651 	for (i = 0; i < count; i++)
652 		array[i] = fdt32_to_cpu(cell[i]);
653 
654 	return count;
655 }
656 
657 const u32 *fdtdec_locate_array(const void *blob, int node,
658 			       const char *prop_name, int count)
659 {
660 	const u32 *cell;
661 	int err;
662 
663 	cell = get_prop_check_min_len(blob, node, prop_name,
664 				      sizeof(u32) * count, &err);
665 	return err ? NULL : cell;
666 }
667 
668 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
669 {
670 	const s32 *cell;
671 	int len;
672 
673 	debug("%s: %s\n", __func__, prop_name);
674 	cell = fdt_getprop(blob, node, prop_name, &len);
675 	return cell != NULL;
676 }
677 
678 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
679 				   const char *list_name,
680 				   const char *cells_name,
681 				   int cell_count, int index,
682 				   struct fdtdec_phandle_args *out_args)
683 {
684 	const __be32 *list, *list_end;
685 	int rc = 0, size, cur_index = 0;
686 	uint32_t count = 0;
687 	int node = -1;
688 	int phandle;
689 
690 	/* Retrieve the phandle list property */
691 	list = fdt_getprop(blob, src_node, list_name, &size);
692 	if (!list)
693 		return -ENOENT;
694 	list_end = list + size / sizeof(*list);
695 
696 	/* Loop over the phandles until all the requested entry is found */
697 	while (list < list_end) {
698 		rc = -EINVAL;
699 		count = 0;
700 
701 		/*
702 		 * If phandle is 0, then it is an empty entry with no
703 		 * arguments.  Skip forward to the next entry.
704 		 */
705 		phandle = be32_to_cpup(list++);
706 		if (phandle) {
707 			/*
708 			 * Find the provider node and parse the #*-cells
709 			 * property to determine the argument length.
710 			 *
711 			 * This is not needed if the cell count is hard-coded
712 			 * (i.e. cells_name not set, but cell_count is set),
713 			 * except when we're going to return the found node
714 			 * below.
715 			 */
716 			if (cells_name || cur_index == index) {
717 				node = fdt_node_offset_by_phandle(blob,
718 								  phandle);
719 				if (!node) {
720 					debug("%s: could not find phandle\n",
721 					      fdt_get_name(blob, src_node,
722 							   NULL));
723 					goto err;
724 				}
725 			}
726 
727 			if (cells_name) {
728 				count = fdtdec_get_int(blob, node, cells_name,
729 						       -1);
730 				if (count == -1) {
731 					debug("%s: could not get %s for %s\n",
732 					      fdt_get_name(blob, src_node,
733 							   NULL),
734 					      cells_name,
735 					      fdt_get_name(blob, node,
736 							   NULL));
737 					goto err;
738 				}
739 			} else {
740 				count = cell_count;
741 			}
742 
743 			/*
744 			 * Make sure that the arguments actually fit in the
745 			 * remaining property data length
746 			 */
747 			if (list + count > list_end) {
748 				debug("%s: arguments longer than property\n",
749 				      fdt_get_name(blob, src_node, NULL));
750 				goto err;
751 			}
752 		}
753 
754 		/*
755 		 * All of the error cases above bail out of the loop, so at
756 		 * this point, the parsing is successful. If the requested
757 		 * index matches, then fill the out_args structure and return,
758 		 * or return -ENOENT for an empty entry.
759 		 */
760 		rc = -ENOENT;
761 		if (cur_index == index) {
762 			if (!phandle)
763 				goto err;
764 
765 			if (out_args) {
766 				int i;
767 
768 				if (count > MAX_PHANDLE_ARGS) {
769 					debug("%s: too many arguments %d\n",
770 					      fdt_get_name(blob, src_node,
771 							   NULL), count);
772 					count = MAX_PHANDLE_ARGS;
773 				}
774 				out_args->node = node;
775 				out_args->args_count = count;
776 				for (i = 0; i < count; i++) {
777 					out_args->args[i] =
778 							be32_to_cpup(list++);
779 				}
780 			}
781 
782 			/* Found it! return success */
783 			return 0;
784 		}
785 
786 		node = -1;
787 		list += count;
788 		cur_index++;
789 	}
790 
791 	/*
792 	 * Result will be one of:
793 	 * -ENOENT : index is for empty phandle
794 	 * -EINVAL : parsing error on data
795 	 * [1..n]  : Number of phandle (count mode; when index = -1)
796 	 */
797 	rc = index < 0 ? cur_index : -ENOENT;
798  err:
799 	return rc;
800 }
801 
802 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
803 		u8 *array, int count)
804 {
805 	const u8 *cell;
806 	int err;
807 
808 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
809 	if (!err)
810 		memcpy(array, cell, count);
811 	return err;
812 }
813 
814 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
815 			     const char *prop_name, int count)
816 {
817 	const u8 *cell;
818 	int err;
819 
820 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
821 	if (err)
822 		return NULL;
823 	return cell;
824 }
825 
826 int fdtdec_get_config_int(const void *blob, const char *prop_name,
827 		int default_val)
828 {
829 	int config_node;
830 
831 	debug("%s: %s\n", __func__, prop_name);
832 	config_node = fdt_path_offset(blob, "/config");
833 	if (config_node < 0)
834 		return default_val;
835 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
836 }
837 
838 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
839 {
840 	int config_node;
841 	const void *prop;
842 
843 	debug("%s: %s\n", __func__, prop_name);
844 	config_node = fdt_path_offset(blob, "/config");
845 	if (config_node < 0)
846 		return 0;
847 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
848 
849 	return prop != NULL;
850 }
851 
852 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
853 {
854 	const char *nodep;
855 	int nodeoffset;
856 	int len;
857 
858 	debug("%s: %s\n", __func__, prop_name);
859 	nodeoffset = fdt_path_offset(blob, "/config");
860 	if (nodeoffset < 0)
861 		return NULL;
862 
863 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
864 	if (!nodep)
865 		return NULL;
866 
867 	return (char *)nodep;
868 }
869 
870 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
871 			 fdt_addr_t *basep, fdt_size_t *sizep)
872 {
873 	const fdt_addr_t *cell;
874 	int len;
875 
876 	debug("%s: %s: %s\n", __func__, fdt_get_name(blob, node, NULL),
877 	      prop_name);
878 	cell = fdt_getprop(blob, node, prop_name, &len);
879 	if (!cell || (len < sizeof(fdt_addr_t) * 2)) {
880 		debug("cell=%p, len=%d\n", cell, len);
881 		return -1;
882 	}
883 
884 	*basep = fdt_addr_to_cpu(*cell);
885 	*sizep = fdt_size_to_cpu(cell[1]);
886 	debug("%s: base=%08lx, size=%lx\n", __func__, (ulong)*basep,
887 	      (ulong)*sizep);
888 
889 	return 0;
890 }
891 
892 /**
893  * Read a flash entry from the fdt
894  *
895  * @param blob		FDT blob
896  * @param node		Offset of node to read
897  * @param name		Name of node being read
898  * @param entry		Place to put offset and size of this node
899  * @return 0 if ok, -ve on error
900  */
901 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
902 			   struct fmap_entry *entry)
903 {
904 	const char *prop;
905 	u32 reg[2];
906 
907 	if (fdtdec_get_int_array(blob, node, "reg", reg, 2)) {
908 		debug("Node '%s' has bad/missing 'reg' property\n", name);
909 		return -FDT_ERR_NOTFOUND;
910 	}
911 	entry->offset = reg[0];
912 	entry->length = reg[1];
913 	entry->used = fdtdec_get_int(blob, node, "used", entry->length);
914 	prop = fdt_getprop(blob, node, "compress", NULL);
915 	entry->compress_algo = prop && !strcmp(prop, "lzo") ?
916 		FMAP_COMPRESS_LZO : FMAP_COMPRESS_NONE;
917 	prop = fdt_getprop(blob, node, "hash", &entry->hash_size);
918 	entry->hash_algo = prop ? FMAP_HASH_SHA256 : FMAP_HASH_NONE;
919 	entry->hash = (uint8_t *)prop;
920 
921 	return 0;
922 }
923 
924 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells)
925 {
926 	u64 number = 0;
927 
928 	while (cells--)
929 		number = (number << 32) | fdt32_to_cpu(*ptr++);
930 
931 	return number;
932 }
933 
934 int fdt_get_resource(const void *fdt, int node, const char *property,
935 		     unsigned int index, struct fdt_resource *res)
936 {
937 	const fdt32_t *ptr, *end;
938 	int na, ns, len, parent;
939 	unsigned int i = 0;
940 
941 	parent = fdt_parent_offset(fdt, node);
942 	if (parent < 0)
943 		return parent;
944 
945 	na = fdt_address_cells(fdt, parent);
946 	ns = fdt_size_cells(fdt, parent);
947 
948 	ptr = fdt_getprop(fdt, node, property, &len);
949 	if (!ptr)
950 		return len;
951 
952 	end = ptr + len / sizeof(*ptr);
953 
954 	while (ptr + na + ns <= end) {
955 		if (i == index) {
956 			res->start = res->end = fdtdec_get_number(ptr, na);
957 			res->end += fdtdec_get_number(&ptr[na], ns) - 1;
958 			return 0;
959 		}
960 
961 		ptr += na + ns;
962 		i++;
963 	}
964 
965 	return -FDT_ERR_NOTFOUND;
966 }
967 
968 int fdt_get_named_resource(const void *fdt, int node, const char *property,
969 			   const char *prop_names, const char *name,
970 			   struct fdt_resource *res)
971 {
972 	int index;
973 
974 	index = fdt_find_string(fdt, node, prop_names, name);
975 	if (index < 0)
976 		return index;
977 
978 	return fdt_get_resource(fdt, node, property, index, res);
979 }
980 
981 int fdtdec_decode_memory_region(const void *blob, int config_node,
982 				const char *mem_type, const char *suffix,
983 				fdt_addr_t *basep, fdt_size_t *sizep)
984 {
985 	char prop_name[50];
986 	const char *mem;
987 	fdt_size_t size, offset_size;
988 	fdt_addr_t base, offset;
989 	int node;
990 
991 	if (config_node == -1) {
992 		config_node = fdt_path_offset(blob, "/config");
993 		if (config_node < 0) {
994 			debug("%s: Cannot find /config node\n", __func__);
995 			return -ENOENT;
996 		}
997 	}
998 	if (!suffix)
999 		suffix = "";
1000 
1001 	snprintf(prop_name, sizeof(prop_name), "%s-memory%s", mem_type,
1002 		 suffix);
1003 	mem = fdt_getprop(blob, config_node, prop_name, NULL);
1004 	if (!mem) {
1005 		debug("%s: No memory type for '%s', using /memory\n", __func__,
1006 		      prop_name);
1007 		mem = "/memory";
1008 	}
1009 
1010 	node = fdt_path_offset(blob, mem);
1011 	if (node < 0) {
1012 		debug("%s: Failed to find node '%s': %s\n", __func__, mem,
1013 		      fdt_strerror(node));
1014 		return -ENOENT;
1015 	}
1016 
1017 	/*
1018 	 * Not strictly correct - the memory may have multiple banks. We just
1019 	 * use the first
1020 	 */
1021 	if (fdtdec_decode_region(blob, node, "reg", &base, &size)) {
1022 		debug("%s: Failed to decode memory region %s\n", __func__,
1023 		      mem);
1024 		return -EINVAL;
1025 	}
1026 
1027 	snprintf(prop_name, sizeof(prop_name), "%s-offset%s", mem_type,
1028 		 suffix);
1029 	if (fdtdec_decode_region(blob, config_node, prop_name, &offset,
1030 				 &offset_size)) {
1031 		debug("%s: Failed to decode memory region '%s'\n", __func__,
1032 		      prop_name);
1033 		return -EINVAL;
1034 	}
1035 
1036 	*basep = base + offset;
1037 	*sizep = offset_size;
1038 
1039 	return 0;
1040 }
1041 
1042 int fdtdec_setup(void)
1043 {
1044 #ifdef CONFIG_OF_CONTROL
1045 # ifdef CONFIG_OF_EMBED
1046 	/* Get a pointer to the FDT */
1047 	gd->fdt_blob = __dtb_dt_begin;
1048 # elif defined CONFIG_OF_SEPARATE
1049 #  ifdef CONFIG_SPL_BUILD
1050 	/* FDT is at end of BSS */
1051 	gd->fdt_blob = (ulong *)&__bss_end;
1052 #  else
1053 	/* FDT is at end of image */
1054 	gd->fdt_blob = (ulong *)&_end;
1055 #endif
1056 # elif defined(CONFIG_OF_HOSTFILE)
1057 	if (sandbox_read_fdt_from_file()) {
1058 		puts("Failed to read control FDT\n");
1059 		return -1;
1060 	}
1061 # endif
1062 # ifndef CONFIG_SPL_BUILD
1063 	/* Allow the early environment to override the fdt address */
1064 	gd->fdt_blob = (void *)getenv_ulong("fdtcontroladdr", 16,
1065 						(uintptr_t)gd->fdt_blob);
1066 # endif
1067 #endif
1068 	return fdtdec_prepare_fdt();
1069 }
1070 
1071 #endif /* !USE_HOSTCC */
1072