xref: /openbmc/u-boot/lib/fdtdec.c (revision bf7716d6)
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_TEGRA124_SDMMC, "nvidia,tegra124-sdhci"),
36 	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
37 	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
38 	COMPAT(NVIDIA_TEGRA20_SFLASH, "nvidia,tegra20-sflash"),
39 	COMPAT(NVIDIA_TEGRA20_SLINK, "nvidia,tegra20-slink"),
40 	COMPAT(NVIDIA_TEGRA114_SPI, "nvidia,tegra114-spi"),
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(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"),
47 	COMPAT(GOOGLE_CROS_EC, "google,cros-ec"),
48 	COMPAT(GOOGLE_CROS_EC_KEYB, "google,cros-ec-keyb"),
49 	COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
50 	COMPAT(SAMSUNG_EXYNOS5_XHCI, "samsung,exynos5250-xhci"),
51 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
52 	COMPAT(SAMSUNG_EXYNOS5_USB3_PHY, "samsung,exynos5250-usb3-phy"),
53 	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
54 	COMPAT(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
55 	COMPAT(SAMSUNG_EXYNOS_MIPI_DSI, "samsung,exynos-mipi-dsi"),
56 	COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
57 	COMPAT(SAMSUNG_EXYNOS5_DWMMC, "samsung,exynos5250-dwmmc"),
58 	COMPAT(SAMSUNG_EXYNOS_MMC, "samsung,exynos-mmc"),
59 	COMPAT(SAMSUNG_EXYNOS_SERIAL, "samsung,exynos4210-uart"),
60 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
61 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
62 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
63 	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
64 	COMPAT(INFINEON_SLB9645_TPM, "infineon,slb9645-tpm"),
65 	COMPAT(SAMSUNG_EXYNOS5_I2C, "samsung,exynos5-hsi2c"),
66 };
67 
68 const char *fdtdec_get_compatible(enum fdt_compat_id id)
69 {
70 	/* We allow reading of the 'unknown' ID for testing purposes */
71 	assert(id >= 0 && id < COMPAT_COUNT);
72 	return compat_names[id];
73 }
74 
75 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
76 		const char *prop_name, fdt_size_t *sizep)
77 {
78 	const fdt_addr_t *cell;
79 	int len;
80 
81 	debug("%s: %s: ", __func__, prop_name);
82 	cell = fdt_getprop(blob, node, prop_name, &len);
83 	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
84 		     len == sizeof(fdt_addr_t) * 2)) {
85 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
86 		if (sizep) {
87 			const fdt_size_t *size;
88 
89 			size = (fdt_size_t *)((char *)cell +
90 					sizeof(fdt_addr_t));
91 			*sizep = fdt_size_to_cpu(*size);
92 			debug("addr=%08lx, size=%08x\n",
93 			      (ulong)addr, *sizep);
94 		} else {
95 			debug("%08lx\n", (ulong)addr);
96 		}
97 		return addr;
98 	}
99 	debug("(not found)\n");
100 	return FDT_ADDR_T_NONE;
101 }
102 
103 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
104 		const char *prop_name)
105 {
106 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
107 }
108 
109 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
110 		s32 default_val)
111 {
112 	const s32 *cell;
113 	int len;
114 
115 	debug("%s: %s: ", __func__, prop_name);
116 	cell = fdt_getprop(blob, node, prop_name, &len);
117 	if (cell && len >= sizeof(s32)) {
118 		s32 val = fdt32_to_cpu(cell[0]);
119 
120 		debug("%#x (%d)\n", val, val);
121 		return val;
122 	}
123 	debug("(not found)\n");
124 	return default_val;
125 }
126 
127 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
128 		uint64_t default_val)
129 {
130 	const uint64_t *cell64;
131 	int length;
132 
133 	cell64 = fdt_getprop(blob, node, prop_name, &length);
134 	if (!cell64 || length < sizeof(*cell64))
135 		return default_val;
136 
137 	return fdt64_to_cpu(*cell64);
138 }
139 
140 int fdtdec_get_is_enabled(const void *blob, int node)
141 {
142 	const char *cell;
143 
144 	/*
145 	 * It should say "okay", so only allow that. Some fdts use "ok" but
146 	 * this is a bug. Please fix your device tree source file. See here
147 	 * for discussion:
148 	 *
149 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
150 	 */
151 	cell = fdt_getprop(blob, node, "status", NULL);
152 	if (cell)
153 		return 0 == strcmp(cell, "okay");
154 	return 1;
155 }
156 
157 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
158 {
159 	enum fdt_compat_id id;
160 
161 	/* Search our drivers */
162 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
163 		if (0 == fdt_node_check_compatible(blob, node,
164 				compat_names[id]))
165 			return id;
166 	return COMPAT_UNKNOWN;
167 }
168 
169 int fdtdec_next_compatible(const void *blob, int node,
170 		enum fdt_compat_id id)
171 {
172 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
173 }
174 
175 int fdtdec_next_compatible_subnode(const void *blob, int node,
176 		enum fdt_compat_id id, int *depthp)
177 {
178 	do {
179 		node = fdt_next_node(blob, node, depthp);
180 	} while (*depthp > 1);
181 
182 	/* If this is a direct subnode, and compatible, return it */
183 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
184 						blob, node, compat_names[id]))
185 		return node;
186 
187 	return -FDT_ERR_NOTFOUND;
188 }
189 
190 int fdtdec_next_alias(const void *blob, const char *name,
191 		enum fdt_compat_id id, int *upto)
192 {
193 #define MAX_STR_LEN 20
194 	char str[MAX_STR_LEN + 20];
195 	int node, err;
196 
197 	/* snprintf() is not available */
198 	assert(strlen(name) < MAX_STR_LEN);
199 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
200 	node = fdt_path_offset(blob, str);
201 	if (node < 0)
202 		return node;
203 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
204 	if (err < 0)
205 		return err;
206 	if (err)
207 		return -FDT_ERR_NOTFOUND;
208 	(*upto)++;
209 	return node;
210 }
211 
212 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
213 			enum fdt_compat_id id, int *node_list, int maxcount)
214 {
215 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
216 
217 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
218 }
219 
220 /* TODO: Can we tighten this code up a little? */
221 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
222 			enum fdt_compat_id id, int *node_list, int maxcount)
223 {
224 	int name_len = strlen(name);
225 	int nodes[maxcount];
226 	int num_found = 0;
227 	int offset, node;
228 	int alias_node;
229 	int count;
230 	int i, j;
231 
232 	/* find the alias node if present */
233 	alias_node = fdt_path_offset(blob, "/aliases");
234 
235 	/*
236 	 * start with nothing, and we can assume that the root node can't
237 	 * match
238 	 */
239 	memset(nodes, '\0', sizeof(nodes));
240 
241 	/* First find all the compatible nodes */
242 	for (node = count = 0; node >= 0 && count < maxcount;) {
243 		node = fdtdec_next_compatible(blob, node, id);
244 		if (node >= 0)
245 			nodes[count++] = node;
246 	}
247 	if (node >= 0)
248 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
249 		       __func__, name);
250 
251 	/* Now find all the aliases */
252 	for (offset = fdt_first_property_offset(blob, alias_node);
253 			offset > 0;
254 			offset = fdt_next_property_offset(blob, offset)) {
255 		const struct fdt_property *prop;
256 		const char *path;
257 		int number;
258 		int found;
259 
260 		node = 0;
261 		prop = fdt_get_property_by_offset(blob, offset, NULL);
262 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
263 		if (prop->len && 0 == strncmp(path, name, name_len))
264 			node = fdt_path_offset(blob, prop->data);
265 		if (node <= 0)
266 			continue;
267 
268 		/* Get the alias number */
269 		number = simple_strtoul(path + name_len, NULL, 10);
270 		if (number < 0 || number >= maxcount) {
271 			debug("%s: warning: alias '%s' is out of range\n",
272 			       __func__, path);
273 			continue;
274 		}
275 
276 		/* Make sure the node we found is actually in our list! */
277 		found = -1;
278 		for (j = 0; j < count; j++)
279 			if (nodes[j] == node) {
280 				found = j;
281 				break;
282 			}
283 
284 		if (found == -1) {
285 			debug("%s: warning: alias '%s' points to a node "
286 				"'%s' that is missing or is not compatible "
287 				" with '%s'\n", __func__, path,
288 				fdt_get_name(blob, node, NULL),
289 			       compat_names[id]);
290 			continue;
291 		}
292 
293 		/*
294 		 * Add this node to our list in the right place, and mark
295 		 * it as done.
296 		 */
297 		if (fdtdec_get_is_enabled(blob, node)) {
298 			if (node_list[number]) {
299 				debug("%s: warning: alias '%s' requires that "
300 				      "a node be placed in the list in a "
301 				      "position which is already filled by "
302 				      "node '%s'\n", __func__, path,
303 				      fdt_get_name(blob, node, NULL));
304 				continue;
305 			}
306 			node_list[number] = node;
307 			if (number >= num_found)
308 				num_found = number + 1;
309 		}
310 		nodes[found] = 0;
311 	}
312 
313 	/* Add any nodes not mentioned by an alias */
314 	for (i = j = 0; i < maxcount; i++) {
315 		if (!node_list[i]) {
316 			for (; j < maxcount; j++)
317 				if (nodes[j] &&
318 					fdtdec_get_is_enabled(blob, nodes[j]))
319 					break;
320 
321 			/* Have we run out of nodes to add? */
322 			if (j == maxcount)
323 				break;
324 
325 			assert(!node_list[i]);
326 			node_list[i] = nodes[j++];
327 			if (i >= num_found)
328 				num_found = i + 1;
329 		}
330 	}
331 
332 	return num_found;
333 }
334 
335 int fdtdec_check_fdt(void)
336 {
337 	/*
338 	 * We must have an FDT, but we cannot panic() yet since the console
339 	 * is not ready. So for now, just assert(). Boards which need an early
340 	 * FDT (prior to console ready) will need to make their own
341 	 * arrangements and do their own checks.
342 	 */
343 	assert(!fdtdec_prepare_fdt());
344 	return 0;
345 }
346 
347 /*
348  * This function is a little odd in that it accesses global data. At some
349  * point if the architecture board.c files merge this will make more sense.
350  * Even now, it is common code.
351  */
352 int fdtdec_prepare_fdt(void)
353 {
354 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
355 	    fdt_check_header(gd->fdt_blob)) {
356 		printf("No valid FDT found - please append one to U-Boot "
357 			"binary, use u-boot-dtb.bin or define "
358 			"CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
359 		return -1;
360 	}
361 	return 0;
362 }
363 
364 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
365 {
366 	const u32 *phandle;
367 	int lookup;
368 
369 	debug("%s: %s\n", __func__, prop_name);
370 	phandle = fdt_getprop(blob, node, prop_name, NULL);
371 	if (!phandle)
372 		return -FDT_ERR_NOTFOUND;
373 
374 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
375 	return lookup;
376 }
377 
378 /**
379  * Look up a property in a node and check that it has a minimum length.
380  *
381  * @param blob		FDT blob
382  * @param node		node to examine
383  * @param prop_name	name of property to find
384  * @param min_len	minimum property length in bytes
385  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
386 			found, or -FDT_ERR_BADLAYOUT if not enough data
387  * @return pointer to cell, which is only valid if err == 0
388  */
389 static const void *get_prop_check_min_len(const void *blob, int node,
390 		const char *prop_name, int min_len, int *err)
391 {
392 	const void *cell;
393 	int len;
394 
395 	debug("%s: %s\n", __func__, prop_name);
396 	cell = fdt_getprop(blob, node, prop_name, &len);
397 	if (!cell)
398 		*err = -FDT_ERR_NOTFOUND;
399 	else if (len < min_len)
400 		*err = -FDT_ERR_BADLAYOUT;
401 	else
402 		*err = 0;
403 	return cell;
404 }
405 
406 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
407 		u32 *array, int count)
408 {
409 	const u32 *cell;
410 	int i, err = 0;
411 
412 	debug("%s: %s\n", __func__, prop_name);
413 	cell = get_prop_check_min_len(blob, node, prop_name,
414 				      sizeof(u32) * count, &err);
415 	if (!err) {
416 		for (i = 0; i < count; i++)
417 			array[i] = fdt32_to_cpu(cell[i]);
418 	}
419 	return err;
420 }
421 
422 const u32 *fdtdec_locate_array(const void *blob, int node,
423 			       const char *prop_name, int count)
424 {
425 	const u32 *cell;
426 	int err;
427 
428 	cell = get_prop_check_min_len(blob, node, prop_name,
429 				      sizeof(u32) * count, &err);
430 	return err ? NULL : cell;
431 }
432 
433 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
434 {
435 	const s32 *cell;
436 	int len;
437 
438 	debug("%s: %s\n", __func__, prop_name);
439 	cell = fdt_getprop(blob, node, prop_name, &len);
440 	return cell != NULL;
441 }
442 
443 /**
444  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
445  * terminating item.
446  *
447  * @param blob		FDT blob to use
448  * @param node		Node to look at
449  * @param prop_name	Node property name
450  * @param gpio		Array of gpio elements to fill from FDT. This will be
451  *			untouched if either 0 or an error is returned
452  * @param max_count	Maximum number of elements allowed
453  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
454  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
455  */
456 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
457 		struct fdt_gpio_state *gpio, int max_count)
458 {
459 	const struct fdt_property *prop;
460 	const u32 *cell;
461 	const char *name;
462 	int len, i;
463 
464 	debug("%s: %s\n", __func__, prop_name);
465 	assert(max_count > 0);
466 	prop = fdt_get_property(blob, node, prop_name, &len);
467 	if (!prop) {
468 		debug("%s: property '%s' missing\n", __func__, prop_name);
469 		return -FDT_ERR_NOTFOUND;
470 	}
471 
472 	/* We will use the name to tag the GPIO */
473 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
474 	cell = (u32 *)prop->data;
475 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
476 	if (len > max_count) {
477 		debug(" %s: too many GPIOs / cells for "
478 			"property '%s'\n", __func__, prop_name);
479 		return -FDT_ERR_BADLAYOUT;
480 	}
481 
482 	/* Read out the GPIO data from the cells */
483 	for (i = 0; i < len; i++, cell += 3) {
484 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
485 		gpio[i].flags = fdt32_to_cpu(cell[2]);
486 		gpio[i].name = name;
487 	}
488 
489 	return len;
490 }
491 
492 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
493 		struct fdt_gpio_state *gpio)
494 {
495 	int err;
496 
497 	debug("%s: %s\n", __func__, prop_name);
498 	gpio->gpio = FDT_GPIO_NONE;
499 	gpio->name = NULL;
500 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
501 	return err == 1 ? 0 : err;
502 }
503 
504 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
505 {
506 	int val;
507 
508 	if (!fdt_gpio_isvalid(gpio))
509 		return -1;
510 
511 	val = gpio_get_value(gpio->gpio);
512 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
513 }
514 
515 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
516 {
517 	if (!fdt_gpio_isvalid(gpio))
518 		return -1;
519 
520 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
521 	return gpio_set_value(gpio->gpio, val);
522 }
523 
524 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
525 {
526 	/*
527 	 * Return success if there is no GPIO defined. This is used for
528 	 * optional GPIOs)
529 	 */
530 	if (!fdt_gpio_isvalid(gpio))
531 		return 0;
532 
533 	if (gpio_request(gpio->gpio, gpio->name))
534 		return -1;
535 	return 0;
536 }
537 
538 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
539 		u8 *array, int count)
540 {
541 	const u8 *cell;
542 	int err;
543 
544 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
545 	if (!err)
546 		memcpy(array, cell, count);
547 	return err;
548 }
549 
550 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
551 			     const char *prop_name, int count)
552 {
553 	const u8 *cell;
554 	int err;
555 
556 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
557 	if (err)
558 		return NULL;
559 	return cell;
560 }
561 
562 int fdtdec_get_config_int(const void *blob, const char *prop_name,
563 		int default_val)
564 {
565 	int config_node;
566 
567 	debug("%s: %s\n", __func__, prop_name);
568 	config_node = fdt_path_offset(blob, "/config");
569 	if (config_node < 0)
570 		return default_val;
571 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
572 }
573 
574 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
575 {
576 	int config_node;
577 	const void *prop;
578 
579 	debug("%s: %s\n", __func__, prop_name);
580 	config_node = fdt_path_offset(blob, "/config");
581 	if (config_node < 0)
582 		return 0;
583 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
584 
585 	return prop != NULL;
586 }
587 
588 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
589 {
590 	const char *nodep;
591 	int nodeoffset;
592 	int len;
593 
594 	debug("%s: %s\n", __func__, prop_name);
595 	nodeoffset = fdt_path_offset(blob, "/config");
596 	if (nodeoffset < 0)
597 		return NULL;
598 
599 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
600 	if (!nodep)
601 		return NULL;
602 
603 	return (char *)nodep;
604 }
605 
606 int fdtdec_decode_region(const void *blob, int node,
607 		const char *prop_name, void **ptrp, size_t *size)
608 {
609 	const fdt_addr_t *cell;
610 	int len;
611 
612 	debug("%s: %s\n", __func__, prop_name);
613 	cell = fdt_getprop(blob, node, prop_name, &len);
614 	if (!cell || (len != sizeof(fdt_addr_t) * 2))
615 		return -1;
616 
617 	*ptrp = map_sysmem(fdt_addr_to_cpu(*cell), *size);
618 	*size = fdt_size_to_cpu(cell[1]);
619 	debug("%s: size=%zx\n", __func__, *size);
620 	return 0;
621 }
622