xref: /openbmc/u-boot/lib/fdtdec.c (revision d7cbcc76)
1 /*
2  * Copyright (c) 2011 The Chromium OS Authors.
3  * SPDX-License-Identifier:	GPL-2.0+
4  */
5 
6 #include <common.h>
7 #include <serial.h>
8 #include <libfdt.h>
9 #include <fdtdec.h>
10 
11 #include <asm/gpio.h>
12 
13 DECLARE_GLOBAL_DATA_PTR;
14 
15 /*
16  * Here are the type we know about. One day we might allow drivers to
17  * register. For now we just put them here. The COMPAT macro allows us to
18  * turn this into a sparse list later, and keeps the ID with the name.
19  */
20 #define COMPAT(id, name) name
21 static const char * const compat_names[COMPAT_COUNT] = {
22 	COMPAT(UNKNOWN, "<none>"),
23 	COMPAT(NVIDIA_TEGRA20_USB, "nvidia,tegra20-ehci"),
24 	COMPAT(NVIDIA_TEGRA30_USB, "nvidia,tegra30-ehci"),
25 	COMPAT(NVIDIA_TEGRA114_USB, "nvidia,tegra114-ehci"),
26 	COMPAT(NVIDIA_TEGRA114_I2C, "nvidia,tegra114-i2c"),
27 	COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"),
28 	COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"),
29 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
30 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
31 	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
32 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
33 	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
34 	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
35 	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
36 	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
37 	COMPAT(NVIDIA_TEGRA20_SFLASH, "nvidia,tegra20-sflash"),
38 	COMPAT(NVIDIA_TEGRA20_SLINK, "nvidia,tegra20-slink"),
39 	COMPAT(NVIDIA_TEGRA114_SPI, "nvidia,tegra114-spi"),
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(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"),
46 	COMPAT(GOOGLE_CROS_EC, "google,cros-ec"),
47 	COMPAT(GOOGLE_CROS_EC_KEYB, "google,cros-ec-keyb"),
48 	COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
49 	COMPAT(SAMSUNG_EXYNOS5_XHCI, "samsung,exynos5250-xhci"),
50 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
51 	COMPAT(SAMSUNG_EXYNOS5_USB3_PHY, "samsung,exynos5250-usb3-phy"),
52 	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
53 	COMPAT(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
54 	COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
55 	COMPAT(SAMSUNG_EXYNOS5_DWMMC, "samsung,exynos5250-dwmmc"),
56 	COMPAT(SAMSUNG_EXYNOS_SERIAL, "samsung,exynos4210-uart"),
57 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
58 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
59 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
60 	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
61 	COMPAT(INFINEON_SLB9645_TPM, "infineon,slb9645-tpm"),
62 	COMPAT(SAMSUNG_EXYNOS5_I2C, "samsung,exynos5-hsi2c"),
63 };
64 
65 const char *fdtdec_get_compatible(enum fdt_compat_id id)
66 {
67 	/* We allow reading of the 'unknown' ID for testing purposes */
68 	assert(id >= 0 && id < COMPAT_COUNT);
69 	return compat_names[id];
70 }
71 
72 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
73 		const char *prop_name, fdt_size_t *sizep)
74 {
75 	const fdt_addr_t *cell;
76 	int len;
77 
78 	debug("%s: %s: ", __func__, prop_name);
79 	cell = fdt_getprop(blob, node, prop_name, &len);
80 	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
81 		     len == sizeof(fdt_addr_t) * 2)) {
82 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
83 		if (sizep) {
84 			const fdt_size_t *size;
85 
86 			size = (fdt_size_t *)((char *)cell +
87 					sizeof(fdt_addr_t));
88 			*sizep = fdt_size_to_cpu(*size);
89 			debug("addr=%08lx, size=%08x\n",
90 			      (ulong)addr, *sizep);
91 		} else {
92 			debug("%08lx\n", (ulong)addr);
93 		}
94 		return addr;
95 	}
96 	debug("(not found)\n");
97 	return FDT_ADDR_T_NONE;
98 }
99 
100 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
101 		const char *prop_name)
102 {
103 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
104 }
105 
106 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
107 		s32 default_val)
108 {
109 	const s32 *cell;
110 	int len;
111 
112 	debug("%s: %s: ", __func__, prop_name);
113 	cell = fdt_getprop(blob, node, prop_name, &len);
114 	if (cell && len >= sizeof(s32)) {
115 		s32 val = fdt32_to_cpu(cell[0]);
116 
117 		debug("%#x (%d)\n", val, val);
118 		return val;
119 	}
120 	debug("(not found)\n");
121 	return default_val;
122 }
123 
124 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
125 		uint64_t default_val)
126 {
127 	const uint64_t *cell64;
128 	int length;
129 
130 	cell64 = fdt_getprop(blob, node, prop_name, &length);
131 	if (!cell64 || length < sizeof(*cell64))
132 		return default_val;
133 
134 	return fdt64_to_cpu(*cell64);
135 }
136 
137 int fdtdec_get_is_enabled(const void *blob, int node)
138 {
139 	const char *cell;
140 
141 	/*
142 	 * It should say "okay", so only allow that. Some fdts use "ok" but
143 	 * this is a bug. Please fix your device tree source file. See here
144 	 * for discussion:
145 	 *
146 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
147 	 */
148 	cell = fdt_getprop(blob, node, "status", NULL);
149 	if (cell)
150 		return 0 == strcmp(cell, "okay");
151 	return 1;
152 }
153 
154 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
155 {
156 	enum fdt_compat_id id;
157 
158 	/* Search our drivers */
159 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
160 		if (0 == fdt_node_check_compatible(blob, node,
161 				compat_names[id]))
162 			return id;
163 	return COMPAT_UNKNOWN;
164 }
165 
166 int fdtdec_next_compatible(const void *blob, int node,
167 		enum fdt_compat_id id)
168 {
169 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
170 }
171 
172 int fdtdec_next_compatible_subnode(const void *blob, int node,
173 		enum fdt_compat_id id, int *depthp)
174 {
175 	do {
176 		node = fdt_next_node(blob, node, depthp);
177 	} while (*depthp > 1);
178 
179 	/* If this is a direct subnode, and compatible, return it */
180 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
181 						blob, node, compat_names[id]))
182 		return node;
183 
184 	return -FDT_ERR_NOTFOUND;
185 }
186 
187 int fdtdec_next_alias(const void *blob, const char *name,
188 		enum fdt_compat_id id, int *upto)
189 {
190 #define MAX_STR_LEN 20
191 	char str[MAX_STR_LEN + 20];
192 	int node, err;
193 
194 	/* snprintf() is not available */
195 	assert(strlen(name) < MAX_STR_LEN);
196 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
197 	node = fdt_path_offset(blob, str);
198 	if (node < 0)
199 		return node;
200 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
201 	if (err < 0)
202 		return err;
203 	if (err)
204 		return -FDT_ERR_NOTFOUND;
205 	(*upto)++;
206 	return node;
207 }
208 
209 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
210 			enum fdt_compat_id id, int *node_list, int maxcount)
211 {
212 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
213 
214 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
215 }
216 
217 /* TODO: Can we tighten this code up a little? */
218 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
219 			enum fdt_compat_id id, int *node_list, int maxcount)
220 {
221 	int name_len = strlen(name);
222 	int nodes[maxcount];
223 	int num_found = 0;
224 	int offset, node;
225 	int alias_node;
226 	int count;
227 	int i, j;
228 
229 	/* find the alias node if present */
230 	alias_node = fdt_path_offset(blob, "/aliases");
231 
232 	/*
233 	 * start with nothing, and we can assume that the root node can't
234 	 * match
235 	 */
236 	memset(nodes, '\0', sizeof(nodes));
237 
238 	/* First find all the compatible nodes */
239 	for (node = count = 0; node >= 0 && count < maxcount;) {
240 		node = fdtdec_next_compatible(blob, node, id);
241 		if (node >= 0)
242 			nodes[count++] = node;
243 	}
244 	if (node >= 0)
245 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
246 		       __func__, name);
247 
248 	/* Now find all the aliases */
249 	for (offset = fdt_first_property_offset(blob, alias_node);
250 			offset > 0;
251 			offset = fdt_next_property_offset(blob, offset)) {
252 		const struct fdt_property *prop;
253 		const char *path;
254 		int number;
255 		int found;
256 
257 		node = 0;
258 		prop = fdt_get_property_by_offset(blob, offset, NULL);
259 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
260 		if (prop->len && 0 == strncmp(path, name, name_len))
261 			node = fdt_path_offset(blob, prop->data);
262 		if (node <= 0)
263 			continue;
264 
265 		/* Get the alias number */
266 		number = simple_strtoul(path + name_len, NULL, 10);
267 		if (number < 0 || number >= maxcount) {
268 			debug("%s: warning: alias '%s' is out of range\n",
269 			       __func__, path);
270 			continue;
271 		}
272 
273 		/* Make sure the node we found is actually in our list! */
274 		found = -1;
275 		for (j = 0; j < count; j++)
276 			if (nodes[j] == node) {
277 				found = j;
278 				break;
279 			}
280 
281 		if (found == -1) {
282 			debug("%s: warning: alias '%s' points to a node "
283 				"'%s' that is missing or is not compatible "
284 				" with '%s'\n", __func__, path,
285 				fdt_get_name(blob, node, NULL),
286 			       compat_names[id]);
287 			continue;
288 		}
289 
290 		/*
291 		 * Add this node to our list in the right place, and mark
292 		 * it as done.
293 		 */
294 		if (fdtdec_get_is_enabled(blob, node)) {
295 			if (node_list[number]) {
296 				debug("%s: warning: alias '%s' requires that "
297 				      "a node be placed in the list in a "
298 				      "position which is already filled by "
299 				      "node '%s'\n", __func__, path,
300 				      fdt_get_name(blob, node, NULL));
301 				continue;
302 			}
303 			node_list[number] = node;
304 			if (number >= num_found)
305 				num_found = number + 1;
306 		}
307 		nodes[found] = 0;
308 	}
309 
310 	/* Add any nodes not mentioned by an alias */
311 	for (i = j = 0; i < maxcount; i++) {
312 		if (!node_list[i]) {
313 			for (; j < maxcount; j++)
314 				if (nodes[j] &&
315 					fdtdec_get_is_enabled(blob, nodes[j]))
316 					break;
317 
318 			/* Have we run out of nodes to add? */
319 			if (j == maxcount)
320 				break;
321 
322 			assert(!node_list[i]);
323 			node_list[i] = nodes[j++];
324 			if (i >= num_found)
325 				num_found = i + 1;
326 		}
327 	}
328 
329 	return num_found;
330 }
331 
332 int fdtdec_check_fdt(void)
333 {
334 	/*
335 	 * We must have an FDT, but we cannot panic() yet since the console
336 	 * is not ready. So for now, just assert(). Boards which need an early
337 	 * FDT (prior to console ready) will need to make their own
338 	 * arrangements and do their own checks.
339 	 */
340 	assert(!fdtdec_prepare_fdt());
341 	return 0;
342 }
343 
344 /*
345  * This function is a little odd in that it accesses global data. At some
346  * point if the architecture board.c files merge this will make more sense.
347  * Even now, it is common code.
348  */
349 int fdtdec_prepare_fdt(void)
350 {
351 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
352 	    fdt_check_header(gd->fdt_blob)) {
353 		printf("No valid FDT found - please append one to U-Boot "
354 			"binary, use u-boot-dtb.bin or define "
355 			"CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
356 		return -1;
357 	}
358 	return 0;
359 }
360 
361 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
362 {
363 	const u32 *phandle;
364 	int lookup;
365 
366 	debug("%s: %s\n", __func__, prop_name);
367 	phandle = fdt_getprop(blob, node, prop_name, NULL);
368 	if (!phandle)
369 		return -FDT_ERR_NOTFOUND;
370 
371 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
372 	return lookup;
373 }
374 
375 /**
376  * Look up a property in a node and check that it has a minimum length.
377  *
378  * @param blob		FDT blob
379  * @param node		node to examine
380  * @param prop_name	name of property to find
381  * @param min_len	minimum property length in bytes
382  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
383 			found, or -FDT_ERR_BADLAYOUT if not enough data
384  * @return pointer to cell, which is only valid if err == 0
385  */
386 static const void *get_prop_check_min_len(const void *blob, int node,
387 		const char *prop_name, int min_len, int *err)
388 {
389 	const void *cell;
390 	int len;
391 
392 	debug("%s: %s\n", __func__, prop_name);
393 	cell = fdt_getprop(blob, node, prop_name, &len);
394 	if (!cell)
395 		*err = -FDT_ERR_NOTFOUND;
396 	else if (len < min_len)
397 		*err = -FDT_ERR_BADLAYOUT;
398 	else
399 		*err = 0;
400 	return cell;
401 }
402 
403 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
404 		u32 *array, int count)
405 {
406 	const u32 *cell;
407 	int i, err = 0;
408 
409 	debug("%s: %s\n", __func__, prop_name);
410 	cell = get_prop_check_min_len(blob, node, prop_name,
411 				      sizeof(u32) * count, &err);
412 	if (!err) {
413 		for (i = 0; i < count; i++)
414 			array[i] = fdt32_to_cpu(cell[i]);
415 	}
416 	return err;
417 }
418 
419 const u32 *fdtdec_locate_array(const void *blob, int node,
420 			       const char *prop_name, int count)
421 {
422 	const u32 *cell;
423 	int err;
424 
425 	cell = get_prop_check_min_len(blob, node, prop_name,
426 				      sizeof(u32) * count, &err);
427 	return err ? NULL : cell;
428 }
429 
430 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
431 {
432 	const s32 *cell;
433 	int len;
434 
435 	debug("%s: %s\n", __func__, prop_name);
436 	cell = fdt_getprop(blob, node, prop_name, &len);
437 	return cell != NULL;
438 }
439 
440 /**
441  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
442  * terminating item.
443  *
444  * @param blob		FDT blob to use
445  * @param node		Node to look at
446  * @param prop_name	Node property name
447  * @param gpio		Array of gpio elements to fill from FDT. This will be
448  *			untouched if either 0 or an error is returned
449  * @param max_count	Maximum number of elements allowed
450  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
451  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
452  */
453 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
454 		struct fdt_gpio_state *gpio, int max_count)
455 {
456 	const struct fdt_property *prop;
457 	const u32 *cell;
458 	const char *name;
459 	int len, i;
460 
461 	debug("%s: %s\n", __func__, prop_name);
462 	assert(max_count > 0);
463 	prop = fdt_get_property(blob, node, prop_name, &len);
464 	if (!prop) {
465 		debug("%s: property '%s' missing\n", __func__, prop_name);
466 		return -FDT_ERR_NOTFOUND;
467 	}
468 
469 	/* We will use the name to tag the GPIO */
470 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
471 	cell = (u32 *)prop->data;
472 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
473 	if (len > max_count) {
474 		debug(" %s: too many GPIOs / cells for "
475 			"property '%s'\n", __func__, prop_name);
476 		return -FDT_ERR_BADLAYOUT;
477 	}
478 
479 	/* Read out the GPIO data from the cells */
480 	for (i = 0; i < len; i++, cell += 3) {
481 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
482 		gpio[i].flags = fdt32_to_cpu(cell[2]);
483 		gpio[i].name = name;
484 	}
485 
486 	return len;
487 }
488 
489 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
490 		struct fdt_gpio_state *gpio)
491 {
492 	int err;
493 
494 	debug("%s: %s\n", __func__, prop_name);
495 	gpio->gpio = FDT_GPIO_NONE;
496 	gpio->name = NULL;
497 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
498 	return err == 1 ? 0 : err;
499 }
500 
501 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
502 {
503 	int val;
504 
505 	if (!fdt_gpio_isvalid(gpio))
506 		return -1;
507 
508 	val = gpio_get_value(gpio->gpio);
509 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
510 }
511 
512 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
513 {
514 	if (!fdt_gpio_isvalid(gpio))
515 		return -1;
516 
517 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
518 	return gpio_set_value(gpio->gpio, val);
519 }
520 
521 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
522 {
523 	/*
524 	 * Return success if there is no GPIO defined. This is used for
525 	 * optional GPIOs)
526 	 */
527 	if (!fdt_gpio_isvalid(gpio))
528 		return 0;
529 
530 	if (gpio_request(gpio->gpio, gpio->name))
531 		return -1;
532 	return 0;
533 }
534 
535 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
536 		u8 *array, int count)
537 {
538 	const u8 *cell;
539 	int err;
540 
541 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
542 	if (!err)
543 		memcpy(array, cell, count);
544 	return err;
545 }
546 
547 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
548 			     const char *prop_name, int count)
549 {
550 	const u8 *cell;
551 	int err;
552 
553 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
554 	if (err)
555 		return NULL;
556 	return cell;
557 }
558 
559 int fdtdec_get_config_int(const void *blob, const char *prop_name,
560 		int default_val)
561 {
562 	int config_node;
563 
564 	debug("%s: %s\n", __func__, prop_name);
565 	config_node = fdt_path_offset(blob, "/config");
566 	if (config_node < 0)
567 		return default_val;
568 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
569 }
570 
571 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
572 {
573 	int config_node;
574 	const void *prop;
575 
576 	debug("%s: %s\n", __func__, prop_name);
577 	config_node = fdt_path_offset(blob, "/config");
578 	if (config_node < 0)
579 		return 0;
580 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
581 
582 	return prop != NULL;
583 }
584 
585 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
586 {
587 	const char *nodep;
588 	int nodeoffset;
589 	int len;
590 
591 	debug("%s: %s\n", __func__, prop_name);
592 	nodeoffset = fdt_path_offset(blob, "/config");
593 	if (nodeoffset < 0)
594 		return NULL;
595 
596 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
597 	if (!nodep)
598 		return NULL;
599 
600 	return (char *)nodep;
601 }
602 
603 int fdtdec_decode_region(const void *blob, int node,
604 		const char *prop_name, void **ptrp, size_t *size)
605 {
606 	const fdt_addr_t *cell;
607 	int len;
608 
609 	debug("%s: %s\n", __func__, prop_name);
610 	cell = fdt_getprop(blob, node, prop_name, &len);
611 	if (!cell || (len != sizeof(fdt_addr_t) * 2))
612 		return -1;
613 
614 	*ptrp = map_sysmem(fdt_addr_to_cpu(*cell), *size);
615 	*size = fdt_size_to_cpu(cell[1]);
616 	debug("%s: size=%zx\n", __func__, *size);
617 	return 0;
618 }
619