xref: /rk3399_rockchip-uboot/lib/fdtdec.c (revision c3bb3c8bb3de2078334f4b95e04d37eed78781c2)
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_TEGRA114_I2C, "nvidia,tegra114-i2c"),
41 	COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"),
42 	COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"),
43 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
44 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
45 	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
46 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
47 	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
48 	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
49 	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
50 	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
51 	COMPAT(NVIDIA_TEGRA20_SFLASH, "nvidia,tegra20-sflash"),
52 	COMPAT(NVIDIA_TEGRA20_SLINK, "nvidia,tegra20-slink"),
53 	COMPAT(NVIDIA_TEGRA114_SPI, "nvidia,tegra114-spi"),
54 	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
55 	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
56 	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
57 	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
58 	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
59 	COMPAT(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"),
60 	COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
61 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
62 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
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(const void *blob, int node,
73 		const char *prop_name)
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 && (len == sizeof(fdt_addr_t) ||
81 			len == sizeof(fdt_addr_t) * 2)) {
82 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
83 
84 		debug("%p\n", (void *)addr);
85 		return addr;
86 	}
87 	debug("(not found)\n");
88 	return FDT_ADDR_T_NONE;
89 }
90 
91 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
92 		s32 default_val)
93 {
94 	const s32 *cell;
95 	int len;
96 
97 	debug("%s: %s: ", __func__, prop_name);
98 	cell = fdt_getprop(blob, node, prop_name, &len);
99 	if (cell && len >= sizeof(s32)) {
100 		s32 val = fdt32_to_cpu(cell[0]);
101 
102 		debug("%#x (%d)\n", val, val);
103 		return val;
104 	}
105 	debug("(not found)\n");
106 	return default_val;
107 }
108 
109 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
110 		uint64_t default_val)
111 {
112 	const uint64_t *cell64;
113 	int length;
114 
115 	cell64 = fdt_getprop(blob, node, prop_name, &length);
116 	if (!cell64 || length < sizeof(*cell64))
117 		return default_val;
118 
119 	return fdt64_to_cpu(*cell64);
120 }
121 
122 int fdtdec_get_is_enabled(const void *blob, int node)
123 {
124 	const char *cell;
125 
126 	/*
127 	 * It should say "okay", so only allow that. Some fdts use "ok" but
128 	 * this is a bug. Please fix your device tree source file. See here
129 	 * for discussion:
130 	 *
131 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
132 	 */
133 	cell = fdt_getprop(blob, node, "status", NULL);
134 	if (cell)
135 		return 0 == strcmp(cell, "okay");
136 	return 1;
137 }
138 
139 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
140 {
141 	enum fdt_compat_id id;
142 
143 	/* Search our drivers */
144 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
145 		if (0 == fdt_node_check_compatible(blob, node,
146 				compat_names[id]))
147 			return id;
148 	return COMPAT_UNKNOWN;
149 }
150 
151 int fdtdec_next_compatible(const void *blob, int node,
152 		enum fdt_compat_id id)
153 {
154 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
155 }
156 
157 int fdtdec_next_compatible_subnode(const void *blob, int node,
158 		enum fdt_compat_id id, int *depthp)
159 {
160 	do {
161 		node = fdt_next_node(blob, node, depthp);
162 	} while (*depthp > 1);
163 
164 	/* If this is a direct subnode, and compatible, return it */
165 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
166 						blob, node, compat_names[id]))
167 		return node;
168 
169 	return -FDT_ERR_NOTFOUND;
170 }
171 
172 int fdtdec_next_alias(const void *blob, const char *name,
173 		enum fdt_compat_id id, int *upto)
174 {
175 #define MAX_STR_LEN 20
176 	char str[MAX_STR_LEN + 20];
177 	int node, err;
178 
179 	/* snprintf() is not available */
180 	assert(strlen(name) < MAX_STR_LEN);
181 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
182 	node = fdt_path_offset(blob, str);
183 	if (node < 0)
184 		return node;
185 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
186 	if (err < 0)
187 		return err;
188 	if (err)
189 		return -FDT_ERR_NOTFOUND;
190 	(*upto)++;
191 	return node;
192 }
193 
194 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
195 			enum fdt_compat_id id, int *node_list, int maxcount)
196 {
197 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
198 
199 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
200 }
201 
202 /* TODO: Can we tighten this code up a little? */
203 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
204 			enum fdt_compat_id id, int *node_list, int maxcount)
205 {
206 	int name_len = strlen(name);
207 	int nodes[maxcount];
208 	int num_found = 0;
209 	int offset, node;
210 	int alias_node;
211 	int count;
212 	int i, j;
213 
214 	/* find the alias node if present */
215 	alias_node = fdt_path_offset(blob, "/aliases");
216 
217 	/*
218 	 * start with nothing, and we can assume that the root node can't
219 	 * match
220 	 */
221 	memset(nodes, '\0', sizeof(nodes));
222 
223 	/* First find all the compatible nodes */
224 	for (node = count = 0; node >= 0 && count < maxcount;) {
225 		node = fdtdec_next_compatible(blob, node, id);
226 		if (node >= 0)
227 			nodes[count++] = node;
228 	}
229 	if (node >= 0)
230 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
231 		       __func__, name);
232 
233 	/* Now find all the aliases */
234 	for (offset = fdt_first_property_offset(blob, alias_node);
235 			offset > 0;
236 			offset = fdt_next_property_offset(blob, offset)) {
237 		const struct fdt_property *prop;
238 		const char *path;
239 		int number;
240 		int found;
241 
242 		node = 0;
243 		prop = fdt_get_property_by_offset(blob, offset, NULL);
244 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
245 		if (prop->len && 0 == strncmp(path, name, name_len))
246 			node = fdt_path_offset(blob, prop->data);
247 		if (node <= 0)
248 			continue;
249 
250 		/* Get the alias number */
251 		number = simple_strtoul(path + name_len, NULL, 10);
252 		if (number < 0 || number >= maxcount) {
253 			debug("%s: warning: alias '%s' is out of range\n",
254 			       __func__, path);
255 			continue;
256 		}
257 
258 		/* Make sure the node we found is actually in our list! */
259 		found = -1;
260 		for (j = 0; j < count; j++)
261 			if (nodes[j] == node) {
262 				found = j;
263 				break;
264 			}
265 
266 		if (found == -1) {
267 			debug("%s: warning: alias '%s' points to a node "
268 				"'%s' that is missing or is not compatible "
269 				" with '%s'\n", __func__, path,
270 				fdt_get_name(blob, node, NULL),
271 			       compat_names[id]);
272 			continue;
273 		}
274 
275 		/*
276 		 * Add this node to our list in the right place, and mark
277 		 * it as done.
278 		 */
279 		if (fdtdec_get_is_enabled(blob, node)) {
280 			if (node_list[number]) {
281 				debug("%s: warning: alias '%s' requires that "
282 				      "a node be placed in the list in a "
283 				      "position which is already filled by "
284 				      "node '%s'\n", __func__, path,
285 				      fdt_get_name(blob, node, NULL));
286 				continue;
287 			}
288 			node_list[number] = node;
289 			if (number >= num_found)
290 				num_found = number + 1;
291 		}
292 		nodes[found] = 0;
293 	}
294 
295 	/* Add any nodes not mentioned by an alias */
296 	for (i = j = 0; i < maxcount; i++) {
297 		if (!node_list[i]) {
298 			for (; j < maxcount; j++)
299 				if (nodes[j] &&
300 					fdtdec_get_is_enabled(blob, nodes[j]))
301 					break;
302 
303 			/* Have we run out of nodes to add? */
304 			if (j == maxcount)
305 				break;
306 
307 			assert(!node_list[i]);
308 			node_list[i] = nodes[j++];
309 			if (i >= num_found)
310 				num_found = i + 1;
311 		}
312 	}
313 
314 	return num_found;
315 }
316 
317 int fdtdec_check_fdt(void)
318 {
319 	/*
320 	 * We must have an FDT, but we cannot panic() yet since the console
321 	 * is not ready. So for now, just assert(). Boards which need an early
322 	 * FDT (prior to console ready) will need to make their own
323 	 * arrangements and do their own checks.
324 	 */
325 	assert(!fdtdec_prepare_fdt());
326 	return 0;
327 }
328 
329 /*
330  * This function is a little odd in that it accesses global data. At some
331  * point if the architecture board.c files merge this will make more sense.
332  * Even now, it is common code.
333  */
334 int fdtdec_prepare_fdt(void)
335 {
336 	if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob)) {
337 		printf("No valid FDT found - please append one to U-Boot "
338 			"binary, use u-boot-dtb.bin or define "
339 			"CONFIG_OF_EMBED\n");
340 		return -1;
341 	}
342 	return 0;
343 }
344 
345 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
346 {
347 	const u32 *phandle;
348 	int lookup;
349 
350 	debug("%s: %s\n", __func__, prop_name);
351 	phandle = fdt_getprop(blob, node, prop_name, NULL);
352 	if (!phandle)
353 		return -FDT_ERR_NOTFOUND;
354 
355 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
356 	return lookup;
357 }
358 
359 /**
360  * Look up a property in a node and check that it has a minimum length.
361  *
362  * @param blob		FDT blob
363  * @param node		node to examine
364  * @param prop_name	name of property to find
365  * @param min_len	minimum property length in bytes
366  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
367 			found, or -FDT_ERR_BADLAYOUT if not enough data
368  * @return pointer to cell, which is only valid if err == 0
369  */
370 static const void *get_prop_check_min_len(const void *blob, int node,
371 		const char *prop_name, int min_len, int *err)
372 {
373 	const void *cell;
374 	int len;
375 
376 	debug("%s: %s\n", __func__, prop_name);
377 	cell = fdt_getprop(blob, node, prop_name, &len);
378 	if (!cell)
379 		*err = -FDT_ERR_NOTFOUND;
380 	else if (len < min_len)
381 		*err = -FDT_ERR_BADLAYOUT;
382 	else
383 		*err = 0;
384 	return cell;
385 }
386 
387 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
388 		u32 *array, int count)
389 {
390 	const u32 *cell;
391 	int i, err = 0;
392 
393 	debug("%s: %s\n", __func__, prop_name);
394 	cell = get_prop_check_min_len(blob, node, prop_name,
395 				      sizeof(u32) * count, &err);
396 	if (!err) {
397 		for (i = 0; i < count; i++)
398 			array[i] = fdt32_to_cpu(cell[i]);
399 	}
400 	return err;
401 }
402 
403 const u32 *fdtdec_locate_array(const void *blob, int node,
404 			       const char *prop_name, int count)
405 {
406 	const u32 *cell;
407 	int err;
408 
409 	cell = get_prop_check_min_len(blob, node, prop_name,
410 				      sizeof(u32) * count, &err);
411 	return err ? NULL : cell;
412 }
413 
414 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
415 {
416 	const s32 *cell;
417 	int len;
418 
419 	debug("%s: %s\n", __func__, prop_name);
420 	cell = fdt_getprop(blob, node, prop_name, &len);
421 	return cell != NULL;
422 }
423 
424 /**
425  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
426  * terminating item.
427  *
428  * @param blob		FDT blob to use
429  * @param node		Node to look at
430  * @param prop_name	Node property name
431  * @param gpio		Array of gpio elements to fill from FDT. This will be
432  *			untouched if either 0 or an error is returned
433  * @param max_count	Maximum number of elements allowed
434  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
435  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
436  */
437 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
438 		struct fdt_gpio_state *gpio, int max_count)
439 {
440 	const struct fdt_property *prop;
441 	const u32 *cell;
442 	const char *name;
443 	int len, i;
444 
445 	debug("%s: %s\n", __func__, prop_name);
446 	assert(max_count > 0);
447 	prop = fdt_get_property(blob, node, prop_name, &len);
448 	if (!prop) {
449 		debug("%s: property '%s' missing\n", __func__, prop_name);
450 		return -FDT_ERR_NOTFOUND;
451 	}
452 
453 	/* We will use the name to tag the GPIO */
454 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
455 	cell = (u32 *)prop->data;
456 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
457 	if (len > max_count) {
458 		debug(" %s: too many GPIOs / cells for "
459 			"property '%s'\n", __func__, prop_name);
460 		return -FDT_ERR_BADLAYOUT;
461 	}
462 
463 	/* Read out the GPIO data from the cells */
464 	for (i = 0; i < len; i++, cell += 3) {
465 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
466 		gpio[i].flags = fdt32_to_cpu(cell[2]);
467 		gpio[i].name = name;
468 	}
469 
470 	return len;
471 }
472 
473 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
474 		struct fdt_gpio_state *gpio)
475 {
476 	int err;
477 
478 	debug("%s: %s\n", __func__, prop_name);
479 	gpio->gpio = FDT_GPIO_NONE;
480 	gpio->name = NULL;
481 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
482 	return err == 1 ? 0 : err;
483 }
484 
485 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
486 {
487 	int val;
488 
489 	if (!fdt_gpio_isvalid(gpio))
490 		return -1;
491 
492 	val = gpio_get_value(gpio->gpio);
493 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
494 }
495 
496 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
497 {
498 	if (!fdt_gpio_isvalid(gpio))
499 		return -1;
500 
501 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
502 	return gpio_set_value(gpio->gpio, val);
503 }
504 
505 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
506 {
507 	/*
508 	 * Return success if there is no GPIO defined. This is used for
509 	 * optional GPIOs)
510 	 */
511 	if (!fdt_gpio_isvalid(gpio))
512 		return 0;
513 
514 	if (gpio_request(gpio->gpio, gpio->name))
515 		return -1;
516 	return 0;
517 }
518 
519 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
520 		u8 *array, int count)
521 {
522 	const u8 *cell;
523 	int err;
524 
525 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
526 	if (!err)
527 		memcpy(array, cell, count);
528 	return err;
529 }
530 
531 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
532 			     const char *prop_name, int count)
533 {
534 	const u8 *cell;
535 	int err;
536 
537 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
538 	if (err)
539 		return NULL;
540 	return cell;
541 }
542 
543 int fdtdec_get_config_int(const void *blob, const char *prop_name,
544 		int default_val)
545 {
546 	int config_node;
547 
548 	debug("%s: %s\n", __func__, prop_name);
549 	config_node = fdt_path_offset(blob, "/config");
550 	if (config_node < 0)
551 		return default_val;
552 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
553 }
554 
555 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
556 {
557 	int config_node;
558 	const void *prop;
559 
560 	debug("%s: %s\n", __func__, prop_name);
561 	config_node = fdt_path_offset(blob, "/config");
562 	if (config_node < 0)
563 		return 0;
564 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
565 
566 	return prop != NULL;
567 }
568 
569 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
570 {
571 	const char *nodep;
572 	int nodeoffset;
573 	int len;
574 
575 	debug("%s: %s\n", __func__, prop_name);
576 	nodeoffset = fdt_path_offset(blob, "/config");
577 	if (nodeoffset < 0)
578 		return NULL;
579 
580 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
581 	if (!nodep)
582 		return NULL;
583 
584 	return (char *)nodep;
585 }
586 
587 int fdtdec_decode_region(const void *blob, int node,
588 		const char *prop_name, void **ptrp, size_t *size)
589 {
590 	const fdt_addr_t *cell;
591 	int len;
592 
593 	debug("%s: %s\n", __func__, prop_name);
594 	cell = fdt_getprop(blob, node, prop_name, &len);
595 	if (!cell || (len != sizeof(fdt_addr_t) * 2))
596 		return -1;
597 
598 	*ptrp = (void *)fdt_addr_to_cpu(*cell);
599 	*size = fdt_size_to_cpu(cell[1]);
600 	debug("%s: size=%zx\n", __func__, *size);
601 	return 0;
602 }
603