xref: /rk3399_rockchip-uboot/lib/fdtdec.c (revision 8f1b46b10480e7fe140d5656c76f6f6de1739f13)
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_TEGRA20_I2C, "nvidia,tegra20-i2c"),
41 	COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"),
42 	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
43 	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
44 	COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"),
45 	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
46 	COMPAT(NVIDIA_TEGRA20_PWM, "nvidia,tegra20-pwm"),
47 	COMPAT(NVIDIA_TEGRA20_DC, "nvidia,tegra20-dc"),
48 	COMPAT(NVIDIA_TEGRA20_SFLASH, "nvidia,tegra20-sflash"),
49 	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
50 	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
51 	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
52 	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
53 	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
54 	COMPAT(SAMSUNG_EXYNOS_SPI, "samsung,exynos-spi"),
55 	COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
56 	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
57 	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
58 };
59 
60 const char *fdtdec_get_compatible(enum fdt_compat_id id)
61 {
62 	/* We allow reading of the 'unknown' ID for testing purposes */
63 	assert(id >= 0 && id < COMPAT_COUNT);
64 	return compat_names[id];
65 }
66 
67 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
68 		const char *prop_name)
69 {
70 	const fdt_addr_t *cell;
71 	int len;
72 
73 	debug("%s: %s: ", __func__, prop_name);
74 	cell = fdt_getprop(blob, node, prop_name, &len);
75 	if (cell && (len == sizeof(fdt_addr_t) ||
76 			len == sizeof(fdt_addr_t) * 2)) {
77 		fdt_addr_t addr = fdt_addr_to_cpu(*cell);
78 
79 		debug("%p\n", (void *)addr);
80 		return addr;
81 	}
82 	debug("(not found)\n");
83 	return FDT_ADDR_T_NONE;
84 }
85 
86 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
87 		s32 default_val)
88 {
89 	const s32 *cell;
90 	int len;
91 
92 	debug("%s: %s: ", __func__, prop_name);
93 	cell = fdt_getprop(blob, node, prop_name, &len);
94 	if (cell && len >= sizeof(s32)) {
95 		s32 val = fdt32_to_cpu(cell[0]);
96 
97 		debug("%#x (%d)\n", val, val);
98 		return val;
99 	}
100 	debug("(not found)\n");
101 	return default_val;
102 }
103 
104 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
105 		uint64_t default_val)
106 {
107 	const uint64_t *cell64;
108 	int length;
109 
110 	cell64 = fdt_getprop(blob, node, prop_name, &length);
111 	if (!cell64 || length < sizeof(*cell64))
112 		return default_val;
113 
114 	return fdt64_to_cpu(*cell64);
115 }
116 
117 int fdtdec_get_is_enabled(const void *blob, int node)
118 {
119 	const char *cell;
120 
121 	/*
122 	 * It should say "okay", so only allow that. Some fdts use "ok" but
123 	 * this is a bug. Please fix your device tree source file. See here
124 	 * for discussion:
125 	 *
126 	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
127 	 */
128 	cell = fdt_getprop(blob, node, "status", NULL);
129 	if (cell)
130 		return 0 == strcmp(cell, "okay");
131 	return 1;
132 }
133 
134 enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
135 {
136 	enum fdt_compat_id id;
137 
138 	/* Search our drivers */
139 	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
140 		if (0 == fdt_node_check_compatible(blob, node,
141 				compat_names[id]))
142 			return id;
143 	return COMPAT_UNKNOWN;
144 }
145 
146 int fdtdec_next_compatible(const void *blob, int node,
147 		enum fdt_compat_id id)
148 {
149 	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
150 }
151 
152 int fdtdec_next_compatible_subnode(const void *blob, int node,
153 		enum fdt_compat_id id, int *depthp)
154 {
155 	do {
156 		node = fdt_next_node(blob, node, depthp);
157 	} while (*depthp > 1);
158 
159 	/* If this is a direct subnode, and compatible, return it */
160 	if (*depthp == 1 && 0 == fdt_node_check_compatible(
161 						blob, node, compat_names[id]))
162 		return node;
163 
164 	return -FDT_ERR_NOTFOUND;
165 }
166 
167 int fdtdec_next_alias(const void *blob, const char *name,
168 		enum fdt_compat_id id, int *upto)
169 {
170 #define MAX_STR_LEN 20
171 	char str[MAX_STR_LEN + 20];
172 	int node, err;
173 
174 	/* snprintf() is not available */
175 	assert(strlen(name) < MAX_STR_LEN);
176 	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
177 	node = fdt_path_offset(blob, str);
178 	if (node < 0)
179 		return node;
180 	err = fdt_node_check_compatible(blob, node, compat_names[id]);
181 	if (err < 0)
182 		return err;
183 	if (err)
184 		return -FDT_ERR_NOTFOUND;
185 	(*upto)++;
186 	return node;
187 }
188 
189 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
190 			enum fdt_compat_id id, int *node_list, int maxcount)
191 {
192 	memset(node_list, '\0', sizeof(*node_list) * maxcount);
193 
194 	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
195 }
196 
197 /* TODO: Can we tighten this code up a little? */
198 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
199 			enum fdt_compat_id id, int *node_list, int maxcount)
200 {
201 	int name_len = strlen(name);
202 	int nodes[maxcount];
203 	int num_found = 0;
204 	int offset, node;
205 	int alias_node;
206 	int count;
207 	int i, j;
208 
209 	/* find the alias node if present */
210 	alias_node = fdt_path_offset(blob, "/aliases");
211 
212 	/*
213 	 * start with nothing, and we can assume that the root node can't
214 	 * match
215 	 */
216 	memset(nodes, '\0', sizeof(nodes));
217 
218 	/* First find all the compatible nodes */
219 	for (node = count = 0; node >= 0 && count < maxcount;) {
220 		node = fdtdec_next_compatible(blob, node, id);
221 		if (node >= 0)
222 			nodes[count++] = node;
223 	}
224 	if (node >= 0)
225 		debug("%s: warning: maxcount exceeded with alias '%s'\n",
226 		       __func__, name);
227 
228 	/* Now find all the aliases */
229 	for (offset = fdt_first_property_offset(blob, alias_node);
230 			offset > 0;
231 			offset = fdt_next_property_offset(blob, offset)) {
232 		const struct fdt_property *prop;
233 		const char *path;
234 		int number;
235 		int found;
236 
237 		node = 0;
238 		prop = fdt_get_property_by_offset(blob, offset, NULL);
239 		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
240 		if (prop->len && 0 == strncmp(path, name, name_len))
241 			node = fdt_path_offset(blob, prop->data);
242 		if (node <= 0)
243 			continue;
244 
245 		/* Get the alias number */
246 		number = simple_strtoul(path + name_len, NULL, 10);
247 		if (number < 0 || number >= maxcount) {
248 			debug("%s: warning: alias '%s' is out of range\n",
249 			       __func__, path);
250 			continue;
251 		}
252 
253 		/* Make sure the node we found is actually in our list! */
254 		found = -1;
255 		for (j = 0; j < count; j++)
256 			if (nodes[j] == node) {
257 				found = j;
258 				break;
259 			}
260 
261 		if (found == -1) {
262 			debug("%s: warning: alias '%s' points to a node "
263 				"'%s' that is missing or is not compatible "
264 				" with '%s'\n", __func__, path,
265 				fdt_get_name(blob, node, NULL),
266 			       compat_names[id]);
267 			continue;
268 		}
269 
270 		/*
271 		 * Add this node to our list in the right place, and mark
272 		 * it as done.
273 		 */
274 		if (fdtdec_get_is_enabled(blob, node)) {
275 			if (node_list[number]) {
276 				debug("%s: warning: alias '%s' requires that "
277 				      "a node be placed in the list in a "
278 				      "position which is already filled by "
279 				      "node '%s'\n", __func__, path,
280 				      fdt_get_name(blob, node, NULL));
281 				continue;
282 			}
283 			node_list[number] = node;
284 			if (number >= num_found)
285 				num_found = number + 1;
286 		}
287 		nodes[found] = 0;
288 	}
289 
290 	/* Add any nodes not mentioned by an alias */
291 	for (i = j = 0; i < maxcount; i++) {
292 		if (!node_list[i]) {
293 			for (; j < maxcount; j++)
294 				if (nodes[j] &&
295 					fdtdec_get_is_enabled(blob, nodes[j]))
296 					break;
297 
298 			/* Have we run out of nodes to add? */
299 			if (j == maxcount)
300 				break;
301 
302 			assert(!node_list[i]);
303 			node_list[i] = nodes[j++];
304 			if (i >= num_found)
305 				num_found = i + 1;
306 		}
307 	}
308 
309 	return num_found;
310 }
311 
312 int fdtdec_check_fdt(void)
313 {
314 	/*
315 	 * We must have an FDT, but we cannot panic() yet since the console
316 	 * is not ready. So for now, just assert(). Boards which need an early
317 	 * FDT (prior to console ready) will need to make their own
318 	 * arrangements and do their own checks.
319 	 */
320 	assert(!fdtdec_prepare_fdt());
321 	return 0;
322 }
323 
324 /*
325  * This function is a little odd in that it accesses global data. At some
326  * point if the architecture board.c files merge this will make more sense.
327  * Even now, it is common code.
328  */
329 int fdtdec_prepare_fdt(void)
330 {
331 	if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob)) {
332 		printf("No valid FDT found - please append one to U-Boot "
333 			"binary, use u-boot-dtb.bin or define "
334 			"CONFIG_OF_EMBED\n");
335 		return -1;
336 	}
337 	return 0;
338 }
339 
340 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
341 {
342 	const u32 *phandle;
343 	int lookup;
344 
345 	debug("%s: %s\n", __func__, prop_name);
346 	phandle = fdt_getprop(blob, node, prop_name, NULL);
347 	if (!phandle)
348 		return -FDT_ERR_NOTFOUND;
349 
350 	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
351 	return lookup;
352 }
353 
354 /**
355  * Look up a property in a node and check that it has a minimum length.
356  *
357  * @param blob		FDT blob
358  * @param node		node to examine
359  * @param prop_name	name of property to find
360  * @param min_len	minimum property length in bytes
361  * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
362 			found, or -FDT_ERR_BADLAYOUT if not enough data
363  * @return pointer to cell, which is only valid if err == 0
364  */
365 static const void *get_prop_check_min_len(const void *blob, int node,
366 		const char *prop_name, int min_len, int *err)
367 {
368 	const void *cell;
369 	int len;
370 
371 	debug("%s: %s\n", __func__, prop_name);
372 	cell = fdt_getprop(blob, node, prop_name, &len);
373 	if (!cell)
374 		*err = -FDT_ERR_NOTFOUND;
375 	else if (len < min_len)
376 		*err = -FDT_ERR_BADLAYOUT;
377 	else
378 		*err = 0;
379 	return cell;
380 }
381 
382 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
383 		u32 *array, int count)
384 {
385 	const u32 *cell;
386 	int i, err = 0;
387 
388 	debug("%s: %s\n", __func__, prop_name);
389 	cell = get_prop_check_min_len(blob, node, prop_name,
390 				      sizeof(u32) * count, &err);
391 	if (!err) {
392 		for (i = 0; i < count; i++)
393 			array[i] = fdt32_to_cpu(cell[i]);
394 	}
395 	return err;
396 }
397 
398 const u32 *fdtdec_locate_array(const void *blob, int node,
399 			       const char *prop_name, int count)
400 {
401 	const u32 *cell;
402 	int err;
403 
404 	cell = get_prop_check_min_len(blob, node, prop_name,
405 				      sizeof(u32) * count, &err);
406 	return err ? NULL : cell;
407 }
408 
409 int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
410 {
411 	const s32 *cell;
412 	int len;
413 
414 	debug("%s: %s\n", __func__, prop_name);
415 	cell = fdt_getprop(blob, node, prop_name, &len);
416 	return cell != NULL;
417 }
418 
419 /**
420  * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
421  * terminating item.
422  *
423  * @param blob		FDT blob to use
424  * @param node		Node to look at
425  * @param prop_name	Node property name
426  * @param gpio		Array of gpio elements to fill from FDT. This will be
427  *			untouched if either 0 or an error is returned
428  * @param max_count	Maximum number of elements allowed
429  * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
430  * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
431  */
432 int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
433 		struct fdt_gpio_state *gpio, int max_count)
434 {
435 	const struct fdt_property *prop;
436 	const u32 *cell;
437 	const char *name;
438 	int len, i;
439 
440 	debug("%s: %s\n", __func__, prop_name);
441 	assert(max_count > 0);
442 	prop = fdt_get_property(blob, node, prop_name, &len);
443 	if (!prop) {
444 		debug("%s: property '%s' missing\n", __func__, prop_name);
445 		return -FDT_ERR_NOTFOUND;
446 	}
447 
448 	/* We will use the name to tag the GPIO */
449 	name = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
450 	cell = (u32 *)prop->data;
451 	len /= sizeof(u32) * 3;		/* 3 cells per GPIO record */
452 	if (len > max_count) {
453 		debug(" %s: too many GPIOs / cells for "
454 			"property '%s'\n", __func__, prop_name);
455 		return -FDT_ERR_BADLAYOUT;
456 	}
457 
458 	/* Read out the GPIO data from the cells */
459 	for (i = 0; i < len; i++, cell += 3) {
460 		gpio[i].gpio = fdt32_to_cpu(cell[1]);
461 		gpio[i].flags = fdt32_to_cpu(cell[2]);
462 		gpio[i].name = name;
463 	}
464 
465 	return len;
466 }
467 
468 int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
469 		struct fdt_gpio_state *gpio)
470 {
471 	int err;
472 
473 	debug("%s: %s\n", __func__, prop_name);
474 	gpio->gpio = FDT_GPIO_NONE;
475 	gpio->name = NULL;
476 	err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1);
477 	return err == 1 ? 0 : err;
478 }
479 
480 int fdtdec_get_gpio(struct fdt_gpio_state *gpio)
481 {
482 	int val;
483 
484 	if (!fdt_gpio_isvalid(gpio))
485 		return -1;
486 
487 	val = gpio_get_value(gpio->gpio);
488 	return gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
489 }
490 
491 int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val)
492 {
493 	if (!fdt_gpio_isvalid(gpio))
494 		return -1;
495 
496 	val = gpio->flags & FDT_GPIO_ACTIVE_LOW ? val ^ 1 : val;
497 	return gpio_set_value(gpio->gpio, val);
498 }
499 
500 int fdtdec_setup_gpio(struct fdt_gpio_state *gpio)
501 {
502 	/*
503 	 * Return success if there is no GPIO defined. This is used for
504 	 * optional GPIOs)
505 	 */
506 	if (!fdt_gpio_isvalid(gpio))
507 		return 0;
508 
509 	if (gpio_request(gpio->gpio, gpio->name))
510 		return -1;
511 	return 0;
512 }
513 
514 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
515 		u8 *array, int count)
516 {
517 	const u8 *cell;
518 	int err;
519 
520 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
521 	if (!err)
522 		memcpy(array, cell, count);
523 	return err;
524 }
525 
526 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
527 			     const char *prop_name, int count)
528 {
529 	const u8 *cell;
530 	int err;
531 
532 	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
533 	if (err)
534 		return NULL;
535 	return cell;
536 }
537 
538 int fdtdec_get_config_int(const void *blob, const char *prop_name,
539 		int default_val)
540 {
541 	int config_node;
542 
543 	debug("%s: %s\n", __func__, prop_name);
544 	config_node = fdt_path_offset(blob, "/config");
545 	if (config_node < 0)
546 		return default_val;
547 	return fdtdec_get_int(blob, config_node, prop_name, default_val);
548 }
549 
550 int fdtdec_get_config_bool(const void *blob, const char *prop_name)
551 {
552 	int config_node;
553 	const void *prop;
554 
555 	debug("%s: %s\n", __func__, prop_name);
556 	config_node = fdt_path_offset(blob, "/config");
557 	if (config_node < 0)
558 		return 0;
559 	prop = fdt_get_property(blob, config_node, prop_name, NULL);
560 
561 	return prop != NULL;
562 }
563 
564 char *fdtdec_get_config_string(const void *blob, const char *prop_name)
565 {
566 	const char *nodep;
567 	int nodeoffset;
568 	int len;
569 
570 	debug("%s: %s\n", __func__, prop_name);
571 	nodeoffset = fdt_path_offset(blob, "/config");
572 	if (nodeoffset < 0)
573 		return NULL;
574 
575 	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
576 	if (!nodep)
577 		return NULL;
578 
579 	return (char *)nodep;
580 }
581 
582 int fdtdec_decode_region(const void *blob, int node,
583 		const char *prop_name, void **ptrp, size_t *size)
584 {
585 	const fdt_addr_t *cell;
586 	int len;
587 
588 	debug("%s: %s\n", __func__, prop_name);
589 	cell = fdt_getprop(blob, node, prop_name, &len);
590 	if (!cell || (len != sizeof(fdt_addr_t) * 2))
591 		return -1;
592 
593 	*ptrp = (void *)fdt_addr_to_cpu(*cell);
594 	*size = fdt_size_to_cpu(cell[1]);
595 	debug("%s: size=%zx\n", __func__, *size);
596 	return 0;
597 }
598