xref: /openbmc/u-boot/lib/fdtdec.c (revision 1a4596601fd395f3afb8f82f3f840c5e00bdd57a)
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_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
50 	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
51 	COMPAT(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
52 	COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
53 	COMPAT(SAMSUNG_EXYNOS5_DWMMC, "samsung,exynos5250-dwmmc"),
54 	COMPAT(SAMSUNG_EXYNOS_SERIAL, "samsung,exynos4210-uart"),
55 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
56 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
57 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
58 	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
59 	COMPAT(INFINEON_SLB9645_TPM, "infineon,slb9645-tpm"),
60 };
61 
62 const char *fdtdec_get_compatible(enum fdt_compat_id id)
63 {
64 	/* We allow reading of the 'unknown' ID for testing purposes */
65 	assert(id >= 0 && id < COMPAT_COUNT);
66 	return compat_names[id];
67 }
68 
69 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
70 		const char *prop_name, fdt_size_t *sizep)
71 {
72 	const fdt_addr_t *cell;
73 	int len;
74 
75 	debug("%s: %s: ", __func__, prop_name);
76 	cell = fdt_getprop(blob, node, prop_name, &len);
77 	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
78 		     len == sizeof(fdt_addr_t) * 2)) {
79 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
80 		if (sizep) {
81 			const fdt_size_t *size;
82 
83 			size = (fdt_size_t *)((char *)cell +
84 					sizeof(fdt_addr_t));
85 			*sizep = fdt_size_to_cpu(*size);
86 			debug("addr=%p, size=%p\n", (void *)addr,
87 			      (void *)*sizep);
88 		} else {
89 			debug("%p\n", (void *)addr);
90 		}
91 		return addr;
92 	}
93 	debug("(not found)\n");
94 	return FDT_ADDR_T_NONE;
95 }
96 
97 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
98 		const char *prop_name)
99 {
100 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
101 }
102 
103 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
104 		s32 default_val)
105 {
106 	const s32 *cell;
107 	int len;
108 
109 	debug("%s: %s: ", __func__, prop_name);
110 	cell = fdt_getprop(blob, node, prop_name, &len);
111 	if (cell && len >= sizeof(s32)) {
112 		s32 val = fdt32_to_cpu(cell[0]);
113 
114 		debug("%#x (%d)\n", val, val);
115 		return val;
116 	}
117 	debug("(not found)\n");
118 	return default_val;
119 }
120 
121 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
122 		uint64_t default_val)
123 {
124 	const uint64_t *cell64;
125 	int length;
126 
127 	cell64 = fdt_getprop(blob, node, prop_name, &length);
128 	if (!cell64 || length < sizeof(*cell64))
129 		return default_val;
130 
131 	return fdt64_to_cpu(*cell64);
132 }
133 
134 int fdtdec_get_is_enabled(const void *blob, int node)
135 {
136 	const char *cell;
137 
138 	/*
139 	 * It should say "okay", so only allow that. Some fdts use "ok" but
140 	 * this is a bug. Please fix your device tree source file. See here
141 	 * for discussion:
142 	 *
143 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
144 	 */
145 	cell = fdt_getprop(blob, node, "status", NULL);
146 	if (cell)
147 		return 0 == strcmp(cell, "okay");
148 	return 1;
149 }
150 
151 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
152 {
153 	enum fdt_compat_id id;
154 
155 	/* Search our drivers */
156 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
157 		if (0 == fdt_node_check_compatible(blob, node,
158 				compat_names[id]))
159 			return id;
160 	return COMPAT_UNKNOWN;
161 }
162 
163 int fdtdec_next_compatible(const void *blob, int node,
164 		enum fdt_compat_id id)
165 {
166 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
167 }
168 
169 int fdtdec_next_compatible_subnode(const void *blob, int node,
170 		enum fdt_compat_id id, int *depthp)
171 {
172 	do {
173 		node = fdt_next_node(blob, node, depthp);
174 	} while (*depthp > 1);
175 
176 	/* If this is a direct subnode, and compatible, return it */
177 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
178 						blob, node, compat_names[id]))
179 		return node;
180 
181 	return -FDT_ERR_NOTFOUND;
182 }
183 
184 int fdtdec_next_alias(const void *blob, const char *name,
185 		enum fdt_compat_id id, int *upto)
186 {
187 #define MAX_STR_LEN 20
188 	char str[MAX_STR_LEN + 20];
189 	int node, err;
190 
191 	/* snprintf() is not available */
192 	assert(strlen(name) < MAX_STR_LEN);
193 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
194 	node = fdt_path_offset(blob, str);
195 	if (node < 0)
196 		return node;
197 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
198 	if (err < 0)
199 		return err;
200 	if (err)
201 		return -FDT_ERR_NOTFOUND;
202 	(*upto)++;
203 	return node;
204 }
205 
206 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
207 			enum fdt_compat_id id, int *node_list, int maxcount)
208 {
209 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
210 
211 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
212 }
213 
214 /* TODO: Can we tighten this code up a little? */
215 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
216 			enum fdt_compat_id id, int *node_list, int maxcount)
217 {
218 	int name_len = strlen(name);
219 	int nodes[maxcount];
220 	int num_found = 0;
221 	int offset, node;
222 	int alias_node;
223 	int count;
224 	int i, j;
225 
226 	/* find the alias node if present */
227 	alias_node = fdt_path_offset(blob, "/aliases");
228 
229 	/*
230 	 * start with nothing, and we can assume that the root node can't
231 	 * match
232 	 */
233 	memset(nodes, '\0', sizeof(nodes));
234 
235 	/* First find all the compatible nodes */
236 	for (node = count = 0; node >= 0 && count < maxcount;) {
237 		node = fdtdec_next_compatible(blob, node, id);
238 		if (node >= 0)
239 			nodes[count++] = node;
240 	}
241 	if (node >= 0)
242 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
243 		       __func__, name);
244 
245 	/* Now find all the aliases */
246 	for (offset = fdt_first_property_offset(blob, alias_node);
247 			offset > 0;
248 			offset = fdt_next_property_offset(blob, offset)) {
249 		const struct fdt_property *prop;
250 		const char *path;
251 		int number;
252 		int found;
253 
254 		node = 0;
255 		prop = fdt_get_property_by_offset(blob, offset, NULL);
256 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
257 		if (prop->len && 0 == strncmp(path, name, name_len))
258 			node = fdt_path_offset(blob, prop->data);
259 		if (node <= 0)
260 			continue;
261 
262 		/* Get the alias number */
263 		number = simple_strtoul(path + name_len, NULL, 10);
264 		if (number < 0 || number >= maxcount) {
265 			debug("%s: warning: alias '%s' is out of range\n",
266 			       __func__, path);
267 			continue;
268 		}
269 
270 		/* Make sure the node we found is actually in our list! */
271 		found = -1;
272 		for (j = 0; j < count; j++)
273 			if (nodes[j] == node) {
274 				found = j;
275 				break;
276 			}
277 
278 		if (found == -1) {
279 			debug("%s: warning: alias '%s' points to a node "
280 				"'%s' that is missing or is not compatible "
281 				" with '%s'\n", __func__, path,
282 				fdt_get_name(blob, node, NULL),
283 			       compat_names[id]);
284 			continue;
285 		}
286 
287 		/*
288 		 * Add this node to our list in the right place, and mark
289 		 * it as done.
290 		 */
291 		if (fdtdec_get_is_enabled(blob, node)) {
292 			if (node_list[number]) {
293 				debug("%s: warning: alias '%s' requires that "
294 				      "a node be placed in the list in a "
295 				      "position which is already filled by "
296 				      "node '%s'\n", __func__, path,
297 				      fdt_get_name(blob, node, NULL));
298 				continue;
299 			}
300 			node_list[number] = node;
301 			if (number >= num_found)
302 				num_found = number + 1;
303 		}
304 		nodes[found] = 0;
305 	}
306 
307 	/* Add any nodes not mentioned by an alias */
308 	for (i = j = 0; i < maxcount; i++) {
309 		if (!node_list[i]) {
310 			for (; j < maxcount; j++)
311 				if (nodes[j] &&
312 					fdtdec_get_is_enabled(blob, nodes[j]))
313 					break;
314 
315 			/* Have we run out of nodes to add? */
316 			if (j == maxcount)
317 				break;
318 
319 			assert(!node_list[i]);
320 			node_list[i] = nodes[j++];
321 			if (i >= num_found)
322 				num_found = i + 1;
323 		}
324 	}
325 
326 	return num_found;
327 }
328 
329 int fdtdec_check_fdt(void)
330 {
331 	/*
332 	 * We must have an FDT, but we cannot panic() yet since the console
333 	 * is not ready. So for now, just assert(). Boards which need an early
334 	 * FDT (prior to console ready) will need to make their own
335 	 * arrangements and do their own checks.
336 	 */
337 	assert(!fdtdec_prepare_fdt());
338 	return 0;
339 }
340 
341 /*
342  * This function is a little odd in that it accesses global data. At some
343  * point if the architecture board.c files merge this will make more sense.
344  * Even now, it is common code.
345  */
346 int fdtdec_prepare_fdt(void)
347 {
348 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
349 	    fdt_check_header(gd->fdt_blob)) {
350 		printf("No valid FDT found - please append one to U-Boot "
351 			"binary, use u-boot-dtb.bin or define "
352 			"CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
353 		return -1;
354 	}
355 	return 0;
356 }
357 
358 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
359 {
360 	const u32 *phandle;
361 	int lookup;
362 
363 	debug("%s: %s\n", __func__, prop_name);
364 	phandle = fdt_getprop(blob, node, prop_name, NULL);
365 	if (!phandle)
366 		return -FDT_ERR_NOTFOUND;
367 
368 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
369 	return lookup;
370 }
371 
372 /**
373  * Look up a property in a node and check that it has a minimum length.
374  *
375  * @param blob		FDT blob
376  * @param node		node to examine
377  * @param prop_name	name of property to find
378  * @param min_len	minimum property length in bytes
379  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
380 			found, or -FDT_ERR_BADLAYOUT if not enough data
381  * @return pointer to cell, which is only valid if err == 0
382  */
383 static const void *get_prop_check_min_len(const void *blob, int node,
384 		const char *prop_name, int min_len, int *err)
385 {
386 	const void *cell;
387 	int len;
388 
389 	debug("%s: %s\n", __func__, prop_name);
390 	cell = fdt_getprop(blob, node, prop_name, &len);
391 	if (!cell)
392 		*err = -FDT_ERR_NOTFOUND;
393 	else if (len < min_len)
394 		*err = -FDT_ERR_BADLAYOUT;
395 	else
396 		*err = 0;
397 	return cell;
398 }
399 
400 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
401 		u32 *array, int count)
402 {
403 	const u32 *cell;
404 	int i, err = 0;
405 
406 	debug("%s: %s\n", __func__, prop_name);
407 	cell = get_prop_check_min_len(blob, node, prop_name,
408 				      sizeof(u32) * count, &err);
409 	if (!err) {
410 		for (i = 0; i < count; i++)
411 			array[i] = fdt32_to_cpu(cell[i]);
412 	}
413 	return err;
414 }
415 
416 const u32 *fdtdec_locate_array(const void *blob, int node,
417 			       const char *prop_name, int count)
418 {
419 	const u32 *cell;
420 	int err;
421 
422 	cell = get_prop_check_min_len(blob, node, prop_name,
423 				      sizeof(u32) * count, &err);
424 	return err ? NULL : cell;
425 }
426 
427 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
428 {
429 	const s32 *cell;
430 	int len;
431 
432 	debug("%s: %s\n", __func__, prop_name);
433 	cell = fdt_getprop(blob, node, prop_name, &len);
434 	return cell != NULL;
435 }
436 
437 /**
438  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
439  * terminating item.
440  *
441  * @param blob		FDT blob to use
442  * @param node		Node to look at
443  * @param prop_name	Node property name
444  * @param gpio		Array of gpio elements to fill from FDT. This will be
445  *			untouched if either 0 or an error is returned
446  * @param max_count	Maximum number of elements allowed
447  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
448  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
449  */
450 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
451 		struct fdt_gpio_state *gpio, int max_count)
452 {
453 	const struct fdt_property *prop;
454 	const u32 *cell;
455 	const char *name;
456 	int len, i;
457 
458 	debug("%s: %s\n", __func__, prop_name);
459 	assert(max_count > 0);
460 	prop = fdt_get_property(blob, node, prop_name, &len);
461 	if (!prop) {
462 		debug("%s: property '%s' missing\n", __func__, prop_name);
463 		return -FDT_ERR_NOTFOUND;
464 	}
465 
466 	/* We will use the name to tag the GPIO */
467 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
468 	cell = (u32 *)prop->data;
469 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
470 	if (len > max_count) {
471 		debug(" %s: too many GPIOs / cells for "
472 			"property '%s'\n", __func__, prop_name);
473 		return -FDT_ERR_BADLAYOUT;
474 	}
475 
476 	/* Read out the GPIO data from the cells */
477 	for (i = 0; i < len; i++, cell += 3) {
478 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
479 		gpio[i].flags = fdt32_to_cpu(cell[2]);
480 		gpio[i].name = name;
481 	}
482 
483 	return len;
484 }
485 
486 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
487 		struct fdt_gpio_state *gpio)
488 {
489 	int err;
490 
491 	debug("%s: %s\n", __func__, prop_name);
492 	gpio->gpio = FDT_GPIO_NONE;
493 	gpio->name = NULL;
494 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
495 	return err == 1 ? 0 : err;
496 }
497 
498 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
499 {
500 	int val;
501 
502 	if (!fdt_gpio_isvalid(gpio))
503 		return -1;
504 
505 	val = gpio_get_value(gpio->gpio);
506 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
507 }
508 
509 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
510 {
511 	if (!fdt_gpio_isvalid(gpio))
512 		return -1;
513 
514 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
515 	return gpio_set_value(gpio->gpio, val);
516 }
517 
518 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
519 {
520 	/*
521 	 * Return success if there is no GPIO defined. This is used for
522 	 * optional GPIOs)
523 	 */
524 	if (!fdt_gpio_isvalid(gpio))
525 		return 0;
526 
527 	if (gpio_request(gpio->gpio, gpio->name))
528 		return -1;
529 	return 0;
530 }
531 
532 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
533 		u8 *array, int count)
534 {
535 	const u8 *cell;
536 	int err;
537 
538 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
539 	if (!err)
540 		memcpy(array, cell, count);
541 	return err;
542 }
543 
544 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
545 			     const char *prop_name, int count)
546 {
547 	const u8 *cell;
548 	int err;
549 
550 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
551 	if (err)
552 		return NULL;
553 	return cell;
554 }
555 
556 int fdtdec_get_config_int(const void *blob, const char *prop_name,
557 		int default_val)
558 {
559 	int config_node;
560 
561 	debug("%s: %s\n", __func__, prop_name);
562 	config_node = fdt_path_offset(blob, "/config");
563 	if (config_node < 0)
564 		return default_val;
565 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
566 }
567 
568 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
569 {
570 	int config_node;
571 	const void *prop;
572 
573 	debug("%s: %s\n", __func__, prop_name);
574 	config_node = fdt_path_offset(blob, "/config");
575 	if (config_node < 0)
576 		return 0;
577 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
578 
579 	return prop != NULL;
580 }
581 
582 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
583 {
584 	const char *nodep;
585 	int nodeoffset;
586 	int len;
587 
588 	debug("%s: %s\n", __func__, prop_name);
589 	nodeoffset = fdt_path_offset(blob, "/config");
590 	if (nodeoffset < 0)
591 		return NULL;
592 
593 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
594 	if (!nodep)
595 		return NULL;
596 
597 	return (char *)nodep;
598 }
599 
600 int fdtdec_decode_region(const void *blob, int node,
601 		const char *prop_name, void **ptrp, size_t *size)
602 {
603 	const fdt_addr_t *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 || (len != sizeof(fdt_addr_t) * 2))
609 		return -1;
610 
611 	*ptrp = (void *)fdt_addr_to_cpu(*cell);
612 	*size = fdt_size_to_cpu(cell[1]);
613 	debug("%s: size=%zx\n", __func__, *size);
614 	return 0;
615 }
616