xref: /openbmc/u-boot/lib/fdtdec.c (revision b46694df)
1 /*
2  * Copyright (c) 2011 The Chromium OS Authors.
3  * See file CREDITS for list of people who contributed to this
4  * project.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation; either version 2 of
9  * the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
19  * MA 02111-1307 USA
20  */
21 
22 #include <common.h>
23 #include <serial.h>
24 #include <libfdt.h>
25 #include <fdtdec.h>
26 
27 #include <asm/gpio.h>
28 
29 DECLARE_GLOBAL_DATA_PTR;
30 
31 /*
32  * Here are the type we know about. One day we might allow drivers to
33  * register. For now we just put them here. The COMPAT macro allows us to
34  * turn this into a sparse list later, and keeps the ID with the name.
35  */
36 #define COMPAT(id, name) name
37 static const char * const compat_names[COMPAT_COUNT] = {
38 	COMPAT(UNKNOWN, "<none>"),
39 	COMPAT(NVIDIA_TEGRA20_USB, "nvidia,tegra20-ehci"),
40 	COMPAT(NVIDIA_TEGRA30_USB, "nvidia,tegra30-ehci"),
41 	COMPAT(NVIDIA_TEGRA114_USB, "nvidia,tegra114-ehci"),
42 	COMPAT(NVIDIA_TEGRA114_I2C, "nvidia,tegra114-i2c"),
43 	COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"),
44 	COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"),
45 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
46 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
47 	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
48 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
49 	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
50 	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
51 	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
52 	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
53 	COMPAT(NVIDIA_TEGRA20_SFLASH, "nvidia,tegra20-sflash"),
54 	COMPAT(NVIDIA_TEGRA20_SLINK, "nvidia,tegra20-slink"),
55 	COMPAT(NVIDIA_TEGRA114_SPI, "nvidia,tegra114-spi"),
56 	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
57 	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
58 	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
59 	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
60 	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
61 	COMPAT(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"),
62 	COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
63 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
64 	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
65 	COMPAT(SAMSUNG_EXYNOS_FIMD, "samsung,exynos-fimd"),
66 	COMPAT(SAMSUNG_EXYNOS5_DP, "samsung,exynos5-dp"),
67 	COMPAT(SAMSUNG_EXYNOS5_DWMMC, "samsung,exynos5250-dwmmc"),
68 	COMPAT(SAMSUNG_EXYNOS_SERIAL, "samsung,exynos4210-uart"),
69 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
70 	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
71 	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
72 	COMPAT(INFINEON_SLB9635_TPM, "infineon,slb9635-tpm"),
73 };
74 
75 const char *fdtdec_get_compatible(enum fdt_compat_id id)
76 {
77 	/* We allow reading of the 'unknown' ID for testing purposes */
78 	assert(id >= 0 && id < COMPAT_COUNT);
79 	return compat_names[id];
80 }
81 
82 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
83 		const char *prop_name, fdt_size_t *sizep)
84 {
85 	const fdt_addr_t *cell;
86 	int len;
87 
88 	debug("%s: %s: ", __func__, prop_name);
89 	cell = fdt_getprop(blob, node, prop_name, &len);
90 	if (cell && ((!sizep && len == sizeof(fdt_addr_t)) ||
91 		     len == sizeof(fdt_addr_t) * 2)) {
92 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
93 		if (sizep) {
94 			const fdt_size_t *size;
95 
96 			size = (fdt_size_t *)((char *)cell +
97 					sizeof(fdt_addr_t));
98 			*sizep = fdt_size_to_cpu(*size);
99 			debug("addr=%p, size=%p\n", (void *)addr,
100 			      (void *)*sizep);
101 		} else {
102 			debug("%p\n", (void *)addr);
103 		}
104 		return addr;
105 	}
106 	debug("(not found)\n");
107 	return FDT_ADDR_T_NONE;
108 }
109 
110 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
111 		const char *prop_name)
112 {
113 	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
114 }
115 
116 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
117 		s32 default_val)
118 {
119 	const s32 *cell;
120 	int len;
121 
122 	debug("%s: %s: ", __func__, prop_name);
123 	cell = fdt_getprop(blob, node, prop_name, &len);
124 	if (cell && len >= sizeof(s32)) {
125 		s32 val = fdt32_to_cpu(cell[0]);
126 
127 		debug("%#x (%d)\n", val, val);
128 		return val;
129 	}
130 	debug("(not found)\n");
131 	return default_val;
132 }
133 
134 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
135 		uint64_t default_val)
136 {
137 	const uint64_t *cell64;
138 	int length;
139 
140 	cell64 = fdt_getprop(blob, node, prop_name, &length);
141 	if (!cell64 || length < sizeof(*cell64))
142 		return default_val;
143 
144 	return fdt64_to_cpu(*cell64);
145 }
146 
147 int fdtdec_get_is_enabled(const void *blob, int node)
148 {
149 	const char *cell;
150 
151 	/*
152 	 * It should say "okay", so only allow that. Some fdts use "ok" but
153 	 * this is a bug. Please fix your device tree source file. See here
154 	 * for discussion:
155 	 *
156 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
157 	 */
158 	cell = fdt_getprop(blob, node, "status", NULL);
159 	if (cell)
160 		return 0 == strcmp(cell, "okay");
161 	return 1;
162 }
163 
164 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
165 {
166 	enum fdt_compat_id id;
167 
168 	/* Search our drivers */
169 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
170 		if (0 == fdt_node_check_compatible(blob, node,
171 				compat_names[id]))
172 			return id;
173 	return COMPAT_UNKNOWN;
174 }
175 
176 int fdtdec_next_compatible(const void *blob, int node,
177 		enum fdt_compat_id id)
178 {
179 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
180 }
181 
182 int fdtdec_next_compatible_subnode(const void *blob, int node,
183 		enum fdt_compat_id id, int *depthp)
184 {
185 	do {
186 		node = fdt_next_node(blob, node, depthp);
187 	} while (*depthp > 1);
188 
189 	/* If this is a direct subnode, and compatible, return it */
190 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
191 						blob, node, compat_names[id]))
192 		return node;
193 
194 	return -FDT_ERR_NOTFOUND;
195 }
196 
197 int fdtdec_next_alias(const void *blob, const char *name,
198 		enum fdt_compat_id id, int *upto)
199 {
200 #define MAX_STR_LEN 20
201 	char str[MAX_STR_LEN + 20];
202 	int node, err;
203 
204 	/* snprintf() is not available */
205 	assert(strlen(name) < MAX_STR_LEN);
206 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
207 	node = fdt_path_offset(blob, str);
208 	if (node < 0)
209 		return node;
210 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
211 	if (err < 0)
212 		return err;
213 	if (err)
214 		return -FDT_ERR_NOTFOUND;
215 	(*upto)++;
216 	return node;
217 }
218 
219 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
220 			enum fdt_compat_id id, int *node_list, int maxcount)
221 {
222 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
223 
224 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
225 }
226 
227 /* TODO: Can we tighten this code up a little? */
228 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
229 			enum fdt_compat_id id, int *node_list, int maxcount)
230 {
231 	int name_len = strlen(name);
232 	int nodes[maxcount];
233 	int num_found = 0;
234 	int offset, node;
235 	int alias_node;
236 	int count;
237 	int i, j;
238 
239 	/* find the alias node if present */
240 	alias_node = fdt_path_offset(blob, "/aliases");
241 
242 	/*
243 	 * start with nothing, and we can assume that the root node can't
244 	 * match
245 	 */
246 	memset(nodes, '\0', sizeof(nodes));
247 
248 	/* First find all the compatible nodes */
249 	for (node = count = 0; node >= 0 && count < maxcount;) {
250 		node = fdtdec_next_compatible(blob, node, id);
251 		if (node >= 0)
252 			nodes[count++] = node;
253 	}
254 	if (node >= 0)
255 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
256 		       __func__, name);
257 
258 	/* Now find all the aliases */
259 	for (offset = fdt_first_property_offset(blob, alias_node);
260 			offset > 0;
261 			offset = fdt_next_property_offset(blob, offset)) {
262 		const struct fdt_property *prop;
263 		const char *path;
264 		int number;
265 		int found;
266 
267 		node = 0;
268 		prop = fdt_get_property_by_offset(blob, offset, NULL);
269 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
270 		if (prop->len && 0 == strncmp(path, name, name_len))
271 			node = fdt_path_offset(blob, prop->data);
272 		if (node <= 0)
273 			continue;
274 
275 		/* Get the alias number */
276 		number = simple_strtoul(path + name_len, NULL, 10);
277 		if (number < 0 || number >= maxcount) {
278 			debug("%s: warning: alias '%s' is out of range\n",
279 			       __func__, path);
280 			continue;
281 		}
282 
283 		/* Make sure the node we found is actually in our list! */
284 		found = -1;
285 		for (j = 0; j < count; j++)
286 			if (nodes[j] == node) {
287 				found = j;
288 				break;
289 			}
290 
291 		if (found == -1) {
292 			debug("%s: warning: alias '%s' points to a node "
293 				"'%s' that is missing or is not compatible "
294 				" with '%s'\n", __func__, path,
295 				fdt_get_name(blob, node, NULL),
296 			       compat_names[id]);
297 			continue;
298 		}
299 
300 		/*
301 		 * Add this node to our list in the right place, and mark
302 		 * it as done.
303 		 */
304 		if (fdtdec_get_is_enabled(blob, node)) {
305 			if (node_list[number]) {
306 				debug("%s: warning: alias '%s' requires that "
307 				      "a node be placed in the list in a "
308 				      "position which is already filled by "
309 				      "node '%s'\n", __func__, path,
310 				      fdt_get_name(blob, node, NULL));
311 				continue;
312 			}
313 			node_list[number] = node;
314 			if (number >= num_found)
315 				num_found = number + 1;
316 		}
317 		nodes[found] = 0;
318 	}
319 
320 	/* Add any nodes not mentioned by an alias */
321 	for (i = j = 0; i < maxcount; i++) {
322 		if (!node_list[i]) {
323 			for (; j < maxcount; j++)
324 				if (nodes[j] &&
325 					fdtdec_get_is_enabled(blob, nodes[j]))
326 					break;
327 
328 			/* Have we run out of nodes to add? */
329 			if (j == maxcount)
330 				break;
331 
332 			assert(!node_list[i]);
333 			node_list[i] = nodes[j++];
334 			if (i >= num_found)
335 				num_found = i + 1;
336 		}
337 	}
338 
339 	return num_found;
340 }
341 
342 int fdtdec_check_fdt(void)
343 {
344 	/*
345 	 * We must have an FDT, but we cannot panic() yet since the console
346 	 * is not ready. So for now, just assert(). Boards which need an early
347 	 * FDT (prior to console ready) will need to make their own
348 	 * arrangements and do their own checks.
349 	 */
350 	assert(!fdtdec_prepare_fdt());
351 	return 0;
352 }
353 
354 /*
355  * This function is a little odd in that it accesses global data. At some
356  * point if the architecture board.c files merge this will make more sense.
357  * Even now, it is common code.
358  */
359 int fdtdec_prepare_fdt(void)
360 {
361 	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
362 	    fdt_check_header(gd->fdt_blob)) {
363 		printf("No valid FDT found - please append one to U-Boot "
364 			"binary, use u-boot-dtb.bin or define "
365 			"CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
366 		return -1;
367 	}
368 	return 0;
369 }
370 
371 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
372 {
373 	const u32 *phandle;
374 	int lookup;
375 
376 	debug("%s: %s\n", __func__, prop_name);
377 	phandle = fdt_getprop(blob, node, prop_name, NULL);
378 	if (!phandle)
379 		return -FDT_ERR_NOTFOUND;
380 
381 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
382 	return lookup;
383 }
384 
385 /**
386  * Look up a property in a node and check that it has a minimum length.
387  *
388  * @param blob		FDT blob
389  * @param node		node to examine
390  * @param prop_name	name of property to find
391  * @param min_len	minimum property length in bytes
392  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
393 			found, or -FDT_ERR_BADLAYOUT if not enough data
394  * @return pointer to cell, which is only valid if err == 0
395  */
396 static const void *get_prop_check_min_len(const void *blob, int node,
397 		const char *prop_name, int min_len, int *err)
398 {
399 	const void *cell;
400 	int len;
401 
402 	debug("%s: %s\n", __func__, prop_name);
403 	cell = fdt_getprop(blob, node, prop_name, &len);
404 	if (!cell)
405 		*err = -FDT_ERR_NOTFOUND;
406 	else if (len < min_len)
407 		*err = -FDT_ERR_BADLAYOUT;
408 	else
409 		*err = 0;
410 	return cell;
411 }
412 
413 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
414 		u32 *array, int count)
415 {
416 	const u32 *cell;
417 	int i, err = 0;
418 
419 	debug("%s: %s\n", __func__, prop_name);
420 	cell = get_prop_check_min_len(blob, node, prop_name,
421 				      sizeof(u32) * count, &err);
422 	if (!err) {
423 		for (i = 0; i < count; i++)
424 			array[i] = fdt32_to_cpu(cell[i]);
425 	}
426 	return err;
427 }
428 
429 const u32 *fdtdec_locate_array(const void *blob, int node,
430 			       const char *prop_name, int count)
431 {
432 	const u32 *cell;
433 	int err;
434 
435 	cell = get_prop_check_min_len(blob, node, prop_name,
436 				      sizeof(u32) * count, &err);
437 	return err ? NULL : cell;
438 }
439 
440 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
441 {
442 	const s32 *cell;
443 	int len;
444 
445 	debug("%s: %s\n", __func__, prop_name);
446 	cell = fdt_getprop(blob, node, prop_name, &len);
447 	return cell != NULL;
448 }
449 
450 /**
451  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
452  * terminating item.
453  *
454  * @param blob		FDT blob to use
455  * @param node		Node to look at
456  * @param prop_name	Node property name
457  * @param gpio		Array of gpio elements to fill from FDT. This will be
458  *			untouched if either 0 or an error is returned
459  * @param max_count	Maximum number of elements allowed
460  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
461  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
462  */
463 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
464 		struct fdt_gpio_state *gpio, int max_count)
465 {
466 	const struct fdt_property *prop;
467 	const u32 *cell;
468 	const char *name;
469 	int len, i;
470 
471 	debug("%s: %s\n", __func__, prop_name);
472 	assert(max_count > 0);
473 	prop = fdt_get_property(blob, node, prop_name, &len);
474 	if (!prop) {
475 		debug("%s: property '%s' missing\n", __func__, prop_name);
476 		return -FDT_ERR_NOTFOUND;
477 	}
478 
479 	/* We will use the name to tag the GPIO */
480 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
481 	cell = (u32 *)prop->data;
482 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
483 	if (len > max_count) {
484 		debug(" %s: too many GPIOs / cells for "
485 			"property '%s'\n", __func__, prop_name);
486 		return -FDT_ERR_BADLAYOUT;
487 	}
488 
489 	/* Read out the GPIO data from the cells */
490 	for (i = 0; i < len; i++, cell += 3) {
491 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
492 		gpio[i].flags = fdt32_to_cpu(cell[2]);
493 		gpio[i].name = name;
494 	}
495 
496 	return len;
497 }
498 
499 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
500 		struct fdt_gpio_state *gpio)
501 {
502 	int err;
503 
504 	debug("%s: %s\n", __func__, prop_name);
505 	gpio->gpio = FDT_GPIO_NONE;
506 	gpio->name = NULL;
507 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
508 	return err == 1 ? 0 : err;
509 }
510 
511 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
512 {
513 	int val;
514 
515 	if (!fdt_gpio_isvalid(gpio))
516 		return -1;
517 
518 	val = gpio_get_value(gpio->gpio);
519 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
520 }
521 
522 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
523 {
524 	if (!fdt_gpio_isvalid(gpio))
525 		return -1;
526 
527 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
528 	return gpio_set_value(gpio->gpio, val);
529 }
530 
531 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
532 {
533 	/*
534 	 * Return success if there is no GPIO defined. This is used for
535 	 * optional GPIOs)
536 	 */
537 	if (!fdt_gpio_isvalid(gpio))
538 		return 0;
539 
540 	if (gpio_request(gpio->gpio, gpio->name))
541 		return -1;
542 	return 0;
543 }
544 
545 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
546 		u8 *array, int count)
547 {
548 	const u8 *cell;
549 	int err;
550 
551 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
552 	if (!err)
553 		memcpy(array, cell, count);
554 	return err;
555 }
556 
557 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
558 			     const char *prop_name, int count)
559 {
560 	const u8 *cell;
561 	int err;
562 
563 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
564 	if (err)
565 		return NULL;
566 	return cell;
567 }
568 
569 int fdtdec_get_config_int(const void *blob, const char *prop_name,
570 		int default_val)
571 {
572 	int config_node;
573 
574 	debug("%s: %s\n", __func__, prop_name);
575 	config_node = fdt_path_offset(blob, "/config");
576 	if (config_node < 0)
577 		return default_val;
578 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
579 }
580 
581 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
582 {
583 	int config_node;
584 	const void *prop;
585 
586 	debug("%s: %s\n", __func__, prop_name);
587 	config_node = fdt_path_offset(blob, "/config");
588 	if (config_node < 0)
589 		return 0;
590 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
591 
592 	return prop != NULL;
593 }
594 
595 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
596 {
597 	const char *nodep;
598 	int nodeoffset;
599 	int len;
600 
601 	debug("%s: %s\n", __func__, prop_name);
602 	nodeoffset = fdt_path_offset(blob, "/config");
603 	if (nodeoffset < 0)
604 		return NULL;
605 
606 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
607 	if (!nodep)
608 		return NULL;
609 
610 	return (char *)nodep;
611 }
612 
613 int fdtdec_decode_region(const void *blob, int node,
614 		const char *prop_name, void **ptrp, size_t *size)
615 {
616 	const fdt_addr_t *cell;
617 	int len;
618 
619 	debug("%s: %s\n", __func__, prop_name);
620 	cell = fdt_getprop(blob, node, prop_name, &len);
621 	if (!cell || (len != sizeof(fdt_addr_t) * 2))
622 		return -1;
623 
624 	*ptrp = (void *)fdt_addr_to_cpu(*cell);
625 	*size = fdt_size_to_cpu(cell[1]);
626 	debug("%s: size=%zx\n", __func__, *size);
627 	return 0;
628 }
629