xref: /openbmc/u-boot/lib/fdtdec.c (revision 7ca6f363)
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_EXYNOS5_DP, "samsung,exynos5-dp"),
56 	COMPAT(SAMSUNG_EXYNOS5_DWMMC, "samsung,exynos5250-dwmmc"),
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 };
65 
66 const char *fdtdec_get_compatible(enum fdt_compat_id id)
67 {
68 	/* We allow reading of the 'unknown' ID for testing purposes */
69 	assert(id >= 0 && id < COMPAT_COUNT);
70 	return compat_names[id];
71 }
72 
73 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
74 		const char *prop_name, fdt_size_t *sizep)
75 {
76 	const fdt_addr_t *cell;
77 	int len;
78 
79 	debug("%s: %s: ", __func__, prop_name);
80 	cell = fdt_getprop(blob, node, prop_name, &len);
81 	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
82 		     len == sizeof(fdt_addr_t) * 2)) {
83 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
84 		if (sizep) {
85 			const fdt_size_t *size;
86 
87 			size = (fdt_size_t *)((char *)cell +
88 					sizeof(fdt_addr_t));
89 			*sizep = fdt_size_to_cpu(*size);
90 			debug("addr=%08lx, size=%08x\n",
91 			      (ulong)addr, *sizep);
92 		} else {
93 			debug("%08lx\n", (ulong)addr);
94 		}
95 		return addr;
96 	}
97 	debug("(not found)\n");
98 	return FDT_ADDR_T_NONE;
99 }
100 
101 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
102 		const char *prop_name)
103 {
104 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
105 }
106 
107 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
108 		s32 default_val)
109 {
110 	const s32 *cell;
111 	int len;
112 
113 	debug("%s: %s: ", __func__, prop_name);
114 	cell = fdt_getprop(blob, node, prop_name, &len);
115 	if (cell && len >= sizeof(s32)) {
116 		s32 val = fdt32_to_cpu(cell[0]);
117 
118 		debug("%#x (%d)\n", val, val);
119 		return val;
120 	}
121 	debug("(not found)\n");
122 	return default_val;
123 }
124 
125 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
126 		uint64_t default_val)
127 {
128 	const uint64_t *cell64;
129 	int length;
130 
131 	cell64 = fdt_getprop(blob, node, prop_name, &length);
132 	if (!cell64 || length < sizeof(*cell64))
133 		return default_val;
134 
135 	return fdt64_to_cpu(*cell64);
136 }
137 
138 int fdtdec_get_is_enabled(const void *blob, int node)
139 {
140 	const char *cell;
141 
142 	/*
143 	 * It should say "okay", so only allow that. Some fdts use "ok" but
144 	 * this is a bug. Please fix your device tree source file. See here
145 	 * for discussion:
146 	 *
147 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
148 	 */
149 	cell = fdt_getprop(blob, node, "status", NULL);
150 	if (cell)
151 		return 0 == strcmp(cell, "okay");
152 	return 1;
153 }
154 
155 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
156 {
157 	enum fdt_compat_id id;
158 
159 	/* Search our drivers */
160 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
161 		if (0 == fdt_node_check_compatible(blob, node,
162 				compat_names[id]))
163 			return id;
164 	return COMPAT_UNKNOWN;
165 }
166 
167 int fdtdec_next_compatible(const void *blob, int node,
168 		enum fdt_compat_id id)
169 {
170 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
171 }
172 
173 int fdtdec_next_compatible_subnode(const void *blob, int node,
174 		enum fdt_compat_id id, int *depthp)
175 {
176 	do {
177 		node = fdt_next_node(blob, node, depthp);
178 	} while (*depthp > 1);
179 
180 	/* If this is a direct subnode, and compatible, return it */
181 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
182 						blob, node, compat_names[id]))
183 		return node;
184 
185 	return -FDT_ERR_NOTFOUND;
186 }
187 
188 int fdtdec_next_alias(const void *blob, const char *name,
189 		enum fdt_compat_id id, int *upto)
190 {
191 #define MAX_STR_LEN 20
192 	char str[MAX_STR_LEN + 20];
193 	int node, err;
194 
195 	/* snprintf() is not available */
196 	assert(strlen(name) < MAX_STR_LEN);
197 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
198 	node = fdt_path_offset(blob, str);
199 	if (node < 0)
200 		return node;
201 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
202 	if (err < 0)
203 		return err;
204 	if (err)
205 		return -FDT_ERR_NOTFOUND;
206 	(*upto)++;
207 	return node;
208 }
209 
210 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
211 			enum fdt_compat_id id, int *node_list, int maxcount)
212 {
213 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
214 
215 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
216 }
217 
218 /* TODO: Can we tighten this code up a little? */
219 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
220 			enum fdt_compat_id id, int *node_list, int maxcount)
221 {
222 	int name_len = strlen(name);
223 	int nodes[maxcount];
224 	int num_found = 0;
225 	int offset, node;
226 	int alias_node;
227 	int count;
228 	int i, j;
229 
230 	/* find the alias node if present */
231 	alias_node = fdt_path_offset(blob, "/aliases");
232 
233 	/*
234 	 * start with nothing, and we can assume that the root node can't
235 	 * match
236 	 */
237 	memset(nodes, '\0', sizeof(nodes));
238 
239 	/* First find all the compatible nodes */
240 	for (node = count = 0; node >= 0 && count < maxcount;) {
241 		node = fdtdec_next_compatible(blob, node, id);
242 		if (node >= 0)
243 			nodes[count++] = node;
244 	}
245 	if (node >= 0)
246 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
247 		       __func__, name);
248 
249 	/* Now find all the aliases */
250 	for (offset = fdt_first_property_offset(blob, alias_node);
251 			offset > 0;
252 			offset = fdt_next_property_offset(blob, offset)) {
253 		const struct fdt_property *prop;
254 		const char *path;
255 		int number;
256 		int found;
257 
258 		node = 0;
259 		prop = fdt_get_property_by_offset(blob, offset, NULL);
260 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
261 		if (prop->len && 0 == strncmp(path, name, name_len))
262 			node = fdt_path_offset(blob, prop->data);
263 		if (node <= 0)
264 			continue;
265 
266 		/* Get the alias number */
267 		number = simple_strtoul(path + name_len, NULL, 10);
268 		if (number < 0 || number >= maxcount) {
269 			debug("%s: warning: alias '%s' is out of range\n",
270 			       __func__, path);
271 			continue;
272 		}
273 
274 		/* Make sure the node we found is actually in our list! */
275 		found = -1;
276 		for (j = 0; j < count; j++)
277 			if (nodes[j] == node) {
278 				found = j;
279 				break;
280 			}
281 
282 		if (found == -1) {
283 			debug("%s: warning: alias '%s' points to a node "
284 				"'%s' that is missing or is not compatible "
285 				" with '%s'\n", __func__, path,
286 				fdt_get_name(blob, node, NULL),
287 			       compat_names[id]);
288 			continue;
289 		}
290 
291 		/*
292 		 * Add this node to our list in the right place, and mark
293 		 * it as done.
294 		 */
295 		if (fdtdec_get_is_enabled(blob, node)) {
296 			if (node_list[number]) {
297 				debug("%s: warning: alias '%s' requires that "
298 				      "a node be placed in the list in a "
299 				      "position which is already filled by "
300 				      "node '%s'\n", __func__, path,
301 				      fdt_get_name(blob, node, NULL));
302 				continue;
303 			}
304 			node_list[number] = node;
305 			if (number >= num_found)
306 				num_found = number + 1;
307 		}
308 		nodes[found] = 0;
309 	}
310 
311 	/* Add any nodes not mentioned by an alias */
312 	for (i = j = 0; i < maxcount; i++) {
313 		if (!node_list[i]) {
314 			for (; j < maxcount; j++)
315 				if (nodes[j] &&
316 					fdtdec_get_is_enabled(blob, nodes[j]))
317 					break;
318 
319 			/* Have we run out of nodes to add? */
320 			if (j == maxcount)
321 				break;
322 
323 			assert(!node_list[i]);
324 			node_list[i] = nodes[j++];
325 			if (i >= num_found)
326 				num_found = i + 1;
327 		}
328 	}
329 
330 	return num_found;
331 }
332 
333 int fdtdec_check_fdt(void)
334 {
335 	/*
336 	 * We must have an FDT, but we cannot panic() yet since the console
337 	 * is not ready. So for now, just assert(). Boards which need an early
338 	 * FDT (prior to console ready) will need to make their own
339 	 * arrangements and do their own checks.
340 	 */
341 	assert(!fdtdec_prepare_fdt());
342 	return 0;
343 }
344 
345 /*
346  * This function is a little odd in that it accesses global data. At some
347  * point if the architecture board.c files merge this will make more sense.
348  * Even now, it is common code.
349  */
350 int fdtdec_prepare_fdt(void)
351 {
352 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
353 	    fdt_check_header(gd->fdt_blob)) {
354 		printf("No valid FDT found - please append one to U-Boot "
355 			"binary, use u-boot-dtb.bin or define "
356 			"CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
357 		return -1;
358 	}
359 	return 0;
360 }
361 
362 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
363 {
364 	const u32 *phandle;
365 	int lookup;
366 
367 	debug("%s: %s\n", __func__, prop_name);
368 	phandle = fdt_getprop(blob, node, prop_name, NULL);
369 	if (!phandle)
370 		return -FDT_ERR_NOTFOUND;
371 
372 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
373 	return lookup;
374 }
375 
376 /**
377  * Look up a property in a node and check that it has a minimum length.
378  *
379  * @param blob		FDT blob
380  * @param node		node to examine
381  * @param prop_name	name of property to find
382  * @param min_len	minimum property length in bytes
383  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
384 			found, or -FDT_ERR_BADLAYOUT if not enough data
385  * @return pointer to cell, which is only valid if err == 0
386  */
387 static const void *get_prop_check_min_len(const void *blob, int node,
388 		const char *prop_name, int min_len, int *err)
389 {
390 	const void *cell;
391 	int len;
392 
393 	debug("%s: %s\n", __func__, prop_name);
394 	cell = fdt_getprop(blob, node, prop_name, &len);
395 	if (!cell)
396 		*err = -FDT_ERR_NOTFOUND;
397 	else if (len < min_len)
398 		*err = -FDT_ERR_BADLAYOUT;
399 	else
400 		*err = 0;
401 	return cell;
402 }
403 
404 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
405 		u32 *array, int count)
406 {
407 	const u32 *cell;
408 	int i, err = 0;
409 
410 	debug("%s: %s\n", __func__, prop_name);
411 	cell = get_prop_check_min_len(blob, node, prop_name,
412 				      sizeof(u32) * count, &err);
413 	if (!err) {
414 		for (i = 0; i < count; i++)
415 			array[i] = fdt32_to_cpu(cell[i]);
416 	}
417 	return err;
418 }
419 
420 const u32 *fdtdec_locate_array(const void *blob, int node,
421 			       const char *prop_name, int count)
422 {
423 	const u32 *cell;
424 	int err;
425 
426 	cell = get_prop_check_min_len(blob, node, prop_name,
427 				      sizeof(u32) * count, &err);
428 	return err ? NULL : cell;
429 }
430 
431 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
432 {
433 	const s32 *cell;
434 	int len;
435 
436 	debug("%s: %s\n", __func__, prop_name);
437 	cell = fdt_getprop(blob, node, prop_name, &len);
438 	return cell != NULL;
439 }
440 
441 /**
442  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
443  * terminating item.
444  *
445  * @param blob		FDT blob to use
446  * @param node		Node to look at
447  * @param prop_name	Node property name
448  * @param gpio		Array of gpio elements to fill from FDT. This will be
449  *			untouched if either 0 or an error is returned
450  * @param max_count	Maximum number of elements allowed
451  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
452  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
453  */
454 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
455 		struct fdt_gpio_state *gpio, int max_count)
456 {
457 	const struct fdt_property *prop;
458 	const u32 *cell;
459 	const char *name;
460 	int len, i;
461 
462 	debug("%s: %s\n", __func__, prop_name);
463 	assert(max_count > 0);
464 	prop = fdt_get_property(blob, node, prop_name, &len);
465 	if (!prop) {
466 		debug("%s: property '%s' missing\n", __func__, prop_name);
467 		return -FDT_ERR_NOTFOUND;
468 	}
469 
470 	/* We will use the name to tag the GPIO */
471 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
472 	cell = (u32 *)prop->data;
473 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
474 	if (len > max_count) {
475 		debug(" %s: too many GPIOs / cells for "
476 			"property '%s'\n", __func__, prop_name);
477 		return -FDT_ERR_BADLAYOUT;
478 	}
479 
480 	/* Read out the GPIO data from the cells */
481 	for (i = 0; i < len; i++, cell += 3) {
482 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
483 		gpio[i].flags = fdt32_to_cpu(cell[2]);
484 		gpio[i].name = name;
485 	}
486 
487 	return len;
488 }
489 
490 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
491 		struct fdt_gpio_state *gpio)
492 {
493 	int err;
494 
495 	debug("%s: %s\n", __func__, prop_name);
496 	gpio->gpio = FDT_GPIO_NONE;
497 	gpio->name = NULL;
498 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
499 	return err == 1 ? 0 : err;
500 }
501 
502 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
503 {
504 	int val;
505 
506 	if (!fdt_gpio_isvalid(gpio))
507 		return -1;
508 
509 	val = gpio_get_value(gpio->gpio);
510 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
511 }
512 
513 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
514 {
515 	if (!fdt_gpio_isvalid(gpio))
516 		return -1;
517 
518 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
519 	return gpio_set_value(gpio->gpio, val);
520 }
521 
522 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
523 {
524 	/*
525 	 * Return success if there is no GPIO defined. This is used for
526 	 * optional GPIOs)
527 	 */
528 	if (!fdt_gpio_isvalid(gpio))
529 		return 0;
530 
531 	if (gpio_request(gpio->gpio, gpio->name))
532 		return -1;
533 	return 0;
534 }
535 
536 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
537 		u8 *array, int count)
538 {
539 	const u8 *cell;
540 	int err;
541 
542 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
543 	if (!err)
544 		memcpy(array, cell, count);
545 	return err;
546 }
547 
548 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
549 			     const char *prop_name, int count)
550 {
551 	const u8 *cell;
552 	int err;
553 
554 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
555 	if (err)
556 		return NULL;
557 	return cell;
558 }
559 
560 int fdtdec_get_config_int(const void *blob, const char *prop_name,
561 		int default_val)
562 {
563 	int config_node;
564 
565 	debug("%s: %s\n", __func__, prop_name);
566 	config_node = fdt_path_offset(blob, "/config");
567 	if (config_node < 0)
568 		return default_val;
569 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
570 }
571 
572 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
573 {
574 	int config_node;
575 	const void *prop;
576 
577 	debug("%s: %s\n", __func__, prop_name);
578 	config_node = fdt_path_offset(blob, "/config");
579 	if (config_node < 0)
580 		return 0;
581 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
582 
583 	return prop != NULL;
584 }
585 
586 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
587 {
588 	const char *nodep;
589 	int nodeoffset;
590 	int len;
591 
592 	debug("%s: %s\n", __func__, prop_name);
593 	nodeoffset = fdt_path_offset(blob, "/config");
594 	if (nodeoffset < 0)
595 		return NULL;
596 
597 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
598 	if (!nodep)
599 		return NULL;
600 
601 	return (char *)nodep;
602 }
603 
604 int fdtdec_decode_region(const void *blob, int node,
605 		const char *prop_name, void **ptrp, size_t *size)
606 {
607 	const fdt_addr_t *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 || (len != sizeof(fdt_addr_t) * 2))
613 		return -1;
614 
615 	*ptrp = map_sysmem(fdt_addr_to_cpu(*cell), *size);
616 	*size = fdt_size_to_cpu(cell[1]);
617 	debug("%s: size=%zx\n", __func__, *size);
618 	return 0;
619 }
620