xref: /openbmc/u-boot/lib/fdtdec.c (revision a5c289b9bca3805fa35e42f389dc8225c6b916be)
1  /*
2   * Copyright (c) 2011 The Chromium OS Authors.
3   * SPDX-License-Identifier:	GPL-2.0+
4   */
5  
6  #ifndef USE_HOSTCC
7  #include <common.h>
8  #include <dm.h>
9  #include <errno.h>
10  #include <serial.h>
11  #include <libfdt.h>
12  #include <fdt_support.h>
13  #include <fdtdec.h>
14  #include <asm/sections.h>
15  #include <linux/ctype.h>
16  
17  DECLARE_GLOBAL_DATA_PTR;
18  
19  /*
20   * Here are the type we know about. One day we might allow drivers to
21   * register. For now we just put them here. The COMPAT macro allows us to
22   * turn this into a sparse list later, and keeps the ID with the name.
23   *
24   * NOTE: This list is basically a TODO list for things that need to be
25   * converted to driver model. So don't add new things here unless there is a
26   * good reason why driver-model conversion is infeasible. Examples include
27   * things which are used before driver model is available.
28   */
29  #define COMPAT(id, name) name
30  static const char * const compat_names[COMPAT_COUNT] = {
31  	COMPAT(UNKNOWN, "<none>"),
32  	COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"),
33  	COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"),
34  	COMPAT(NVIDIA_TEGRA20_NAND, "nvidia,tegra20-nand"),
35  	COMPAT(NVIDIA_TEGRA124_PMC, "nvidia,tegra124-pmc"),
36  	COMPAT(NVIDIA_TEGRA186_SDMMC, "nvidia,tegra186-sdhci"),
37  	COMPAT(NVIDIA_TEGRA210_SDMMC, "nvidia,tegra210-sdhci"),
38  	COMPAT(NVIDIA_TEGRA124_SDMMC, "nvidia,tegra124-sdhci"),
39  	COMPAT(NVIDIA_TEGRA30_SDMMC, "nvidia,tegra30-sdhci"),
40  	COMPAT(NVIDIA_TEGRA20_SDMMC, "nvidia,tegra20-sdhci"),
41  	COMPAT(NVIDIA_TEGRA124_XUSB_PADCTL, "nvidia,tegra124-xusb-padctl"),
42  	COMPAT(NVIDIA_TEGRA210_XUSB_PADCTL, "nvidia,tegra210-xusb-padctl"),
43  	COMPAT(SMSC_LAN9215, "smsc,lan9215"),
44  	COMPAT(SAMSUNG_EXYNOS5_SROMC, "samsung,exynos-sromc"),
45  	COMPAT(SAMSUNG_S3C2440_I2C, "samsung,s3c2440-i2c"),
46  	COMPAT(SAMSUNG_EXYNOS5_SOUND, "samsung,exynos-sound"),
47  	COMPAT(WOLFSON_WM8994_CODEC, "wolfson,wm8994-codec"),
48  	COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
49  	COMPAT(SAMSUNG_EXYNOS5_USB3_PHY, "samsung,exynos5250-usb3-phy"),
50  	COMPAT(SAMSUNG_EXYNOS_TMU, "samsung,exynos-tmu"),
51  	COMPAT(SAMSUNG_EXYNOS_MIPI_DSI, "samsung,exynos-mipi-dsi"),
52  	COMPAT(SAMSUNG_EXYNOS_DWMMC, "samsung,exynos-dwmmc"),
53  	COMPAT(SAMSUNG_EXYNOS_MMC, "samsung,exynos-mmc"),
54  	COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686"),
55  	COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
56  	COMPAT(MAXIM_98095_CODEC, "maxim,max98095-codec"),
57  	COMPAT(SAMSUNG_EXYNOS5_I2C, "samsung,exynos5-hsi2c"),
58  	COMPAT(SAMSUNG_EXYNOS_SYSMMU, "samsung,sysmmu-v3.3"),
59  	COMPAT(INTEL_MICROCODE, "intel,microcode"),
60  	COMPAT(AMS_AS3722, "ams,as3722"),
61  	COMPAT(INTEL_QRK_MRC, "intel,quark-mrc"),
62  	COMPAT(ALTERA_SOCFPGA_DWMAC, "altr,socfpga-stmmac"),
63  	COMPAT(ALTERA_SOCFPGA_DWMMC, "altr,socfpga-dw-mshc"),
64  	COMPAT(ALTERA_SOCFPGA_DWC2USB, "snps,dwc2"),
65  	COMPAT(INTEL_BAYTRAIL_FSP, "intel,baytrail-fsp"),
66  	COMPAT(INTEL_BAYTRAIL_FSP_MDP, "intel,baytrail-fsp-mdp"),
67  	COMPAT(INTEL_IVYBRIDGE_FSP, "intel,ivybridge-fsp"),
68  	COMPAT(COMPAT_SUNXI_NAND, "allwinner,sun4i-a10-nand"),
69  };
70  
71  const char *fdtdec_get_compatible(enum fdt_compat_id id)
72  {
73  	/* We allow reading of the 'unknown' ID for testing purposes */
74  	assert(id >= 0 && id < COMPAT_COUNT);
75  	return compat_names[id];
76  }
77  
78  fdt_addr_t fdtdec_get_addr_size_fixed(const void *blob, int node,
79  		const char *prop_name, int index, int na, int ns,
80  		fdt_size_t *sizep, bool translate)
81  {
82  	const fdt32_t *prop, *prop_end;
83  	const fdt32_t *prop_addr, *prop_size, *prop_after_size;
84  	int len;
85  	fdt_addr_t addr;
86  
87  	debug("%s: %s: ", __func__, prop_name);
88  
89  	if (na > (sizeof(fdt_addr_t) / sizeof(fdt32_t))) {
90  		debug("(na too large for fdt_addr_t type)\n");
91  		return FDT_ADDR_T_NONE;
92  	}
93  
94  	if (ns > (sizeof(fdt_size_t) / sizeof(fdt32_t))) {
95  		debug("(ns too large for fdt_size_t type)\n");
96  		return FDT_ADDR_T_NONE;
97  	}
98  
99  	prop = fdt_getprop(blob, node, prop_name, &len);
100  	if (!prop) {
101  		debug("(not found)\n");
102  		return FDT_ADDR_T_NONE;
103  	}
104  	prop_end = prop + (len / sizeof(*prop));
105  
106  	prop_addr = prop + (index * (na + ns));
107  	prop_size = prop_addr + na;
108  	prop_after_size = prop_size + ns;
109  	if (prop_after_size > prop_end) {
110  		debug("(not enough data: expected >= %d cells, got %d cells)\n",
111  		      (u32)(prop_after_size - prop), ((u32)(prop_end - prop)));
112  		return FDT_ADDR_T_NONE;
113  	}
114  
115  #if !defined(CONFIG_SPL_BUILD) && defined(CONFIG_OF_LIBFDT)
116  	if (translate)
117  		addr = fdt_translate_address(blob, node, prop_addr);
118  	else
119  #endif
120  		addr = fdtdec_get_number(prop_addr, na);
121  
122  	if (sizep) {
123  		*sizep = fdtdec_get_number(prop_size, ns);
124  		debug("addr=%08llx, size=%llx\n", (unsigned long long)addr,
125  		      (unsigned long long)*sizep);
126  	} else {
127  		debug("addr=%08llx\n", (unsigned long long)addr);
128  	}
129  
130  	return addr;
131  }
132  
133  fdt_addr_t fdtdec_get_addr_size_auto_parent(const void *blob, int parent,
134  		int node, const char *prop_name, int index, fdt_size_t *sizep,
135  		bool translate)
136  {
137  	int na, ns;
138  
139  	debug("%s: ", __func__);
140  
141  	na = fdt_address_cells(blob, parent);
142  	if (na < 1) {
143  		debug("(bad #address-cells)\n");
144  		return FDT_ADDR_T_NONE;
145  	}
146  
147  	ns = fdt_size_cells(blob, parent);
148  	if (ns < 0) {
149  		debug("(bad #size-cells)\n");
150  		return FDT_ADDR_T_NONE;
151  	}
152  
153  	debug("na=%d, ns=%d, ", na, ns);
154  
155  	return fdtdec_get_addr_size_fixed(blob, node, prop_name, index, na,
156  					  ns, sizep, translate);
157  }
158  
159  fdt_addr_t fdtdec_get_addr_size_auto_noparent(const void *blob, int node,
160  		const char *prop_name, int index, fdt_size_t *sizep,
161  		bool translate)
162  {
163  	int parent;
164  
165  	debug("%s: ", __func__);
166  
167  	parent = fdt_parent_offset(blob, node);
168  	if (parent < 0) {
169  		debug("(no parent found)\n");
170  		return FDT_ADDR_T_NONE;
171  	}
172  
173  	return fdtdec_get_addr_size_auto_parent(blob, parent, node, prop_name,
174  						index, sizep, translate);
175  }
176  
177  fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
178  		const char *prop_name, fdt_size_t *sizep)
179  {
180  	int ns = sizep ? (sizeof(fdt_size_t) / sizeof(fdt32_t)) : 0;
181  
182  	return fdtdec_get_addr_size_fixed(blob, node, prop_name, 0,
183  					  sizeof(fdt_addr_t) / sizeof(fdt32_t),
184  					  ns, sizep, false);
185  }
186  
187  fdt_addr_t fdtdec_get_addr(const void *blob, int node,
188  		const char *prop_name)
189  {
190  	return fdtdec_get_addr_size(blob, node, prop_name, NULL);
191  }
192  
193  #if defined(CONFIG_PCI) && defined(CONFIG_DM_PCI)
194  int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
195  		const char *prop_name, struct fdt_pci_addr *addr)
196  {
197  	const u32 *cell;
198  	int len;
199  	int ret = -ENOENT;
200  
201  	debug("%s: %s: ", __func__, prop_name);
202  
203  	/*
204  	 * If we follow the pci bus bindings strictly, we should check
205  	 * the value of the node's parent node's #address-cells and
206  	 * #size-cells. They need to be 3 and 2 accordingly. However,
207  	 * for simplicity we skip the check here.
208  	 */
209  	cell = fdt_getprop(blob, node, prop_name, &len);
210  	if (!cell)
211  		goto fail;
212  
213  	if ((len % FDT_PCI_REG_SIZE) == 0) {
214  		int num = len / FDT_PCI_REG_SIZE;
215  		int i;
216  
217  		for (i = 0; i < num; i++) {
218  			debug("pci address #%d: %08lx %08lx %08lx\n", i,
219  			      (ulong)fdt32_to_cpu(cell[0]),
220  			      (ulong)fdt32_to_cpu(cell[1]),
221  			      (ulong)fdt32_to_cpu(cell[2]));
222  			if ((fdt32_to_cpu(*cell) & type) == type) {
223  				addr->phys_hi = fdt32_to_cpu(cell[0]);
224  				addr->phys_mid = fdt32_to_cpu(cell[1]);
225  				addr->phys_lo = fdt32_to_cpu(cell[1]);
226  				break;
227  			} else {
228  				cell += (FDT_PCI_ADDR_CELLS +
229  					 FDT_PCI_SIZE_CELLS);
230  			}
231  		}
232  
233  		if (i == num) {
234  			ret = -ENXIO;
235  			goto fail;
236  		}
237  
238  		return 0;
239  	} else {
240  		ret = -EINVAL;
241  	}
242  
243  fail:
244  	debug("(not found)\n");
245  	return ret;
246  }
247  
248  int fdtdec_get_pci_vendev(const void *blob, int node, u16 *vendor, u16 *device)
249  {
250  	const char *list, *end;
251  	int len;
252  
253  	list = fdt_getprop(blob, node, "compatible", &len);
254  	if (!list)
255  		return -ENOENT;
256  
257  	end = list + len;
258  	while (list < end) {
259  		char *s;
260  
261  		len = strlen(list);
262  		if (len >= strlen("pciVVVV,DDDD")) {
263  			s = strstr(list, "pci");
264  
265  			/*
266  			 * check if the string is something like pciVVVV,DDDD.RR
267  			 * or just pciVVVV,DDDD
268  			 */
269  			if (s && s[7] == ',' &&
270  			    (s[12] == '.' || s[12] == 0)) {
271  				s += 3;
272  				*vendor = simple_strtol(s, NULL, 16);
273  
274  				s += 5;
275  				*device = simple_strtol(s, NULL, 16);
276  
277  				return 0;
278  			}
279  		}
280  		list += (len + 1);
281  	}
282  
283  	return -ENOENT;
284  }
285  
286  int fdtdec_get_pci_bar32(struct udevice *dev, struct fdt_pci_addr *addr,
287  			 u32 *bar)
288  {
289  	int barnum;
290  
291  	/* extract the bar number from fdt_pci_addr */
292  	barnum = addr->phys_hi & 0xff;
293  	if ((barnum < PCI_BASE_ADDRESS_0) || (barnum > PCI_CARDBUS_CIS))
294  		return -EINVAL;
295  
296  	barnum = (barnum - PCI_BASE_ADDRESS_0) / 4;
297  	*bar = dm_pci_read_bar32(dev, barnum);
298  
299  	return 0;
300  }
301  #endif
302  
303  uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
304  		uint64_t default_val)
305  {
306  	const uint64_t *cell64;
307  	int length;
308  
309  	cell64 = fdt_getprop(blob, node, prop_name, &length);
310  	if (!cell64 || length < sizeof(*cell64))
311  		return default_val;
312  
313  	return fdt64_to_cpu(*cell64);
314  }
315  
316  int fdtdec_get_is_enabled(const void *blob, int node)
317  {
318  	const char *cell;
319  
320  	/*
321  	 * It should say "okay", so only allow that. Some fdts use "ok" but
322  	 * this is a bug. Please fix your device tree source file. See here
323  	 * for discussion:
324  	 *
325  	 * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html
326  	 */
327  	cell = fdt_getprop(blob, node, "status", NULL);
328  	if (cell)
329  		return 0 == strcmp(cell, "okay");
330  	return 1;
331  }
332  
333  enum fdt_compat_id fdtdec_lookup(const void *blob, int node)
334  {
335  	enum fdt_compat_id id;
336  
337  	/* Search our drivers */
338  	for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++)
339  		if (0 == fdt_node_check_compatible(blob, node,
340  				compat_names[id]))
341  			return id;
342  	return COMPAT_UNKNOWN;
343  }
344  
345  int fdtdec_next_compatible(const void *blob, int node,
346  		enum fdt_compat_id id)
347  {
348  	return fdt_node_offset_by_compatible(blob, node, compat_names[id]);
349  }
350  
351  int fdtdec_next_compatible_subnode(const void *blob, int node,
352  		enum fdt_compat_id id, int *depthp)
353  {
354  	do {
355  		node = fdt_next_node(blob, node, depthp);
356  	} while (*depthp > 1);
357  
358  	/* If this is a direct subnode, and compatible, return it */
359  	if (*depthp == 1 && 0 == fdt_node_check_compatible(
360  						blob, node, compat_names[id]))
361  		return node;
362  
363  	return -FDT_ERR_NOTFOUND;
364  }
365  
366  int fdtdec_next_alias(const void *blob, const char *name,
367  		enum fdt_compat_id id, int *upto)
368  {
369  #define MAX_STR_LEN 20
370  	char str[MAX_STR_LEN + 20];
371  	int node, err;
372  
373  	/* snprintf() is not available */
374  	assert(strlen(name) < MAX_STR_LEN);
375  	sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto);
376  	node = fdt_path_offset(blob, str);
377  	if (node < 0)
378  		return node;
379  	err = fdt_node_check_compatible(blob, node, compat_names[id]);
380  	if (err < 0)
381  		return err;
382  	if (err)
383  		return -FDT_ERR_NOTFOUND;
384  	(*upto)++;
385  	return node;
386  }
387  
388  int fdtdec_find_aliases_for_id(const void *blob, const char *name,
389  			enum fdt_compat_id id, int *node_list, int maxcount)
390  {
391  	memset(node_list, '\0', sizeof(*node_list) * maxcount);
392  
393  	return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount);
394  }
395  
396  /* TODO: Can we tighten this code up a little? */
397  int fdtdec_add_aliases_for_id(const void *blob, const char *name,
398  			enum fdt_compat_id id, int *node_list, int maxcount)
399  {
400  	int name_len = strlen(name);
401  	int nodes[maxcount];
402  	int num_found = 0;
403  	int offset, node;
404  	int alias_node;
405  	int count;
406  	int i, j;
407  
408  	/* find the alias node if present */
409  	alias_node = fdt_path_offset(blob, "/aliases");
410  
411  	/*
412  	 * start with nothing, and we can assume that the root node can't
413  	 * match
414  	 */
415  	memset(nodes, '\0', sizeof(nodes));
416  
417  	/* First find all the compatible nodes */
418  	for (node = count = 0; node >= 0 && count < maxcount;) {
419  		node = fdtdec_next_compatible(blob, node, id);
420  		if (node >= 0)
421  			nodes[count++] = node;
422  	}
423  	if (node >= 0)
424  		debug("%s: warning: maxcount exceeded with alias '%s'\n",
425  		       __func__, name);
426  
427  	/* Now find all the aliases */
428  	for (offset = fdt_first_property_offset(blob, alias_node);
429  			offset > 0;
430  			offset = fdt_next_property_offset(blob, offset)) {
431  		const struct fdt_property *prop;
432  		const char *path;
433  		int number;
434  		int found;
435  
436  		node = 0;
437  		prop = fdt_get_property_by_offset(blob, offset, NULL);
438  		path = fdt_string(blob, fdt32_to_cpu(prop->nameoff));
439  		if (prop->len && 0 == strncmp(path, name, name_len))
440  			node = fdt_path_offset(blob, prop->data);
441  		if (node <= 0)
442  			continue;
443  
444  		/* Get the alias number */
445  		number = simple_strtoul(path + name_len, NULL, 10);
446  		if (number < 0 || number >= maxcount) {
447  			debug("%s: warning: alias '%s' is out of range\n",
448  			       __func__, path);
449  			continue;
450  		}
451  
452  		/* Make sure the node we found is actually in our list! */
453  		found = -1;
454  		for (j = 0; j < count; j++)
455  			if (nodes[j] == node) {
456  				found = j;
457  				break;
458  			}
459  
460  		if (found == -1) {
461  			debug("%s: warning: alias '%s' points to a node "
462  				"'%s' that is missing or is not compatible "
463  				" with '%s'\n", __func__, path,
464  				fdt_get_name(blob, node, NULL),
465  			       compat_names[id]);
466  			continue;
467  		}
468  
469  		/*
470  		 * Add this node to our list in the right place, and mark
471  		 * it as done.
472  		 */
473  		if (fdtdec_get_is_enabled(blob, node)) {
474  			if (node_list[number]) {
475  				debug("%s: warning: alias '%s' requires that "
476  				      "a node be placed in the list in a "
477  				      "position which is already filled by "
478  				      "node '%s'\n", __func__, path,
479  				      fdt_get_name(blob, node, NULL));
480  				continue;
481  			}
482  			node_list[number] = node;
483  			if (number >= num_found)
484  				num_found = number + 1;
485  		}
486  		nodes[found] = 0;
487  	}
488  
489  	/* Add any nodes not mentioned by an alias */
490  	for (i = j = 0; i < maxcount; i++) {
491  		if (!node_list[i]) {
492  			for (; j < maxcount; j++)
493  				if (nodes[j] &&
494  					fdtdec_get_is_enabled(blob, nodes[j]))
495  					break;
496  
497  			/* Have we run out of nodes to add? */
498  			if (j == maxcount)
499  				break;
500  
501  			assert(!node_list[i]);
502  			node_list[i] = nodes[j++];
503  			if (i >= num_found)
504  				num_found = i + 1;
505  		}
506  	}
507  
508  	return num_found;
509  }
510  
511  int fdtdec_get_alias_seq(const void *blob, const char *base, int offset,
512  			 int *seqp)
513  {
514  	int base_len = strlen(base);
515  	const char *find_name;
516  	int find_namelen;
517  	int prop_offset;
518  	int aliases;
519  
520  	find_name = fdt_get_name(blob, offset, &find_namelen);
521  	debug("Looking for '%s' at %d, name %s\n", base, offset, find_name);
522  
523  	aliases = fdt_path_offset(blob, "/aliases");
524  	for (prop_offset = fdt_first_property_offset(blob, aliases);
525  	     prop_offset > 0;
526  	     prop_offset = fdt_next_property_offset(blob, prop_offset)) {
527  		const char *prop;
528  		const char *name;
529  		const char *slash;
530  		int len, val;
531  
532  		prop = fdt_getprop_by_offset(blob, prop_offset, &name, &len);
533  		debug("   - %s, %s\n", name, prop);
534  		if (len < find_namelen || *prop != '/' || prop[len - 1] ||
535  		    strncmp(name, base, base_len))
536  			continue;
537  
538  		slash = strrchr(prop, '/');
539  		if (strcmp(slash + 1, find_name))
540  			continue;
541  		val = trailing_strtol(name);
542  		if (val != -1) {
543  			*seqp = val;
544  			debug("Found seq %d\n", *seqp);
545  			return 0;
546  		}
547  	}
548  
549  	debug("Not found\n");
550  	return -ENOENT;
551  }
552  
553  const char *fdtdec_get_chosen_prop(const void *blob, const char *name)
554  {
555  	int chosen_node;
556  
557  	if (!blob)
558  		return NULL;
559  	chosen_node = fdt_path_offset(blob, "/chosen");
560  	return fdt_getprop(blob, chosen_node, name, NULL);
561  }
562  
563  int fdtdec_get_chosen_node(const void *blob, const char *name)
564  {
565  	const char *prop;
566  
567  	prop = fdtdec_get_chosen_prop(blob, name);
568  	if (!prop)
569  		return -FDT_ERR_NOTFOUND;
570  	return fdt_path_offset(blob, prop);
571  }
572  
573  int fdtdec_check_fdt(void)
574  {
575  	/*
576  	 * We must have an FDT, but we cannot panic() yet since the console
577  	 * is not ready. So for now, just assert(). Boards which need an early
578  	 * FDT (prior to console ready) will need to make their own
579  	 * arrangements and do their own checks.
580  	 */
581  	assert(!fdtdec_prepare_fdt());
582  	return 0;
583  }
584  
585  /*
586   * This function is a little odd in that it accesses global data. At some
587   * point if the architecture board.c files merge this will make more sense.
588   * Even now, it is common code.
589   */
590  int fdtdec_prepare_fdt(void)
591  {
592  	if (!gd->fdt_blob || ((uintptr_t)gd->fdt_blob & 3) ||
593  	    fdt_check_header(gd->fdt_blob)) {
594  #ifdef CONFIG_SPL_BUILD
595  		puts("Missing DTB\n");
596  #else
597  		puts("No valid device tree binary found - please append one to U-Boot binary, use u-boot-dtb.bin or define CONFIG_OF_EMBED. For sandbox, use -d <file.dtb>\n");
598  # ifdef DEBUG
599  		if (gd->fdt_blob) {
600  			printf("fdt_blob=%p\n", gd->fdt_blob);
601  			print_buffer((ulong)gd->fdt_blob, gd->fdt_blob, 4,
602  				     32, 0);
603  		}
604  # endif
605  #endif
606  		return -1;
607  	}
608  	return 0;
609  }
610  
611  int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name)
612  {
613  	const u32 *phandle;
614  	int lookup;
615  
616  	debug("%s: %s\n", __func__, prop_name);
617  	phandle = fdt_getprop(blob, node, prop_name, NULL);
618  	if (!phandle)
619  		return -FDT_ERR_NOTFOUND;
620  
621  	lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle));
622  	return lookup;
623  }
624  
625  /**
626   * Look up a property in a node and check that it has a minimum length.
627   *
628   * @param blob		FDT blob
629   * @param node		node to examine
630   * @param prop_name	name of property to find
631   * @param min_len	minimum property length in bytes
632   * @param err		0 if ok, or -FDT_ERR_NOTFOUND if the property is not
633  			found, or -FDT_ERR_BADLAYOUT if not enough data
634   * @return pointer to cell, which is only valid if err == 0
635   */
636  static const void *get_prop_check_min_len(const void *blob, int node,
637  		const char *prop_name, int min_len, int *err)
638  {
639  	const void *cell;
640  	int len;
641  
642  	debug("%s: %s\n", __func__, prop_name);
643  	cell = fdt_getprop(blob, node, prop_name, &len);
644  	if (!cell)
645  		*err = -FDT_ERR_NOTFOUND;
646  	else if (len < min_len)
647  		*err = -FDT_ERR_BADLAYOUT;
648  	else
649  		*err = 0;
650  	return cell;
651  }
652  
653  int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
654  		u32 *array, int count)
655  {
656  	const u32 *cell;
657  	int i, err = 0;
658  
659  	debug("%s: %s\n", __func__, prop_name);
660  	cell = get_prop_check_min_len(blob, node, prop_name,
661  				      sizeof(u32) * count, &err);
662  	if (!err) {
663  		for (i = 0; i < count; i++)
664  			array[i] = fdt32_to_cpu(cell[i]);
665  	}
666  	return err;
667  }
668  
669  int fdtdec_get_int_array_count(const void *blob, int node,
670  			       const char *prop_name, u32 *array, int count)
671  {
672  	const u32 *cell;
673  	int len, elems;
674  	int i;
675  
676  	debug("%s: %s\n", __func__, prop_name);
677  	cell = fdt_getprop(blob, node, prop_name, &len);
678  	if (!cell)
679  		return -FDT_ERR_NOTFOUND;
680  	elems = len / sizeof(u32);
681  	if (count > elems)
682  		count = elems;
683  	for (i = 0; i < count; i++)
684  		array[i] = fdt32_to_cpu(cell[i]);
685  
686  	return count;
687  }
688  
689  const u32 *fdtdec_locate_array(const void *blob, int node,
690  			       const char *prop_name, int count)
691  {
692  	const u32 *cell;
693  	int err;
694  
695  	cell = get_prop_check_min_len(blob, node, prop_name,
696  				      sizeof(u32) * count, &err);
697  	return err ? NULL : cell;
698  }
699  
700  int fdtdec_get_bool(const void *blob, int node, const char *prop_name)
701  {
702  	const s32 *cell;
703  	int len;
704  
705  	debug("%s: %s\n", __func__, prop_name);
706  	cell = fdt_getprop(blob, node, prop_name, &len);
707  	return cell != NULL;
708  }
709  
710  int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
711  				   const char *list_name,
712  				   const char *cells_name,
713  				   int cell_count, int index,
714  				   struct fdtdec_phandle_args *out_args)
715  {
716  	const __be32 *list, *list_end;
717  	int rc = 0, size, cur_index = 0;
718  	uint32_t count = 0;
719  	int node = -1;
720  	int phandle;
721  
722  	/* Retrieve the phandle list property */
723  	list = fdt_getprop(blob, src_node, list_name, &size);
724  	if (!list)
725  		return -ENOENT;
726  	list_end = list + size / sizeof(*list);
727  
728  	/* Loop over the phandles until all the requested entry is found */
729  	while (list < list_end) {
730  		rc = -EINVAL;
731  		count = 0;
732  
733  		/*
734  		 * If phandle is 0, then it is an empty entry with no
735  		 * arguments.  Skip forward to the next entry.
736  		 */
737  		phandle = be32_to_cpup(list++);
738  		if (phandle) {
739  			/*
740  			 * Find the provider node and parse the #*-cells
741  			 * property to determine the argument length.
742  			 *
743  			 * This is not needed if the cell count is hard-coded
744  			 * (i.e. cells_name not set, but cell_count is set),
745  			 * except when we're going to return the found node
746  			 * below.
747  			 */
748  			if (cells_name || cur_index == index) {
749  				node = fdt_node_offset_by_phandle(blob,
750  								  phandle);
751  				if (!node) {
752  					debug("%s: could not find phandle\n",
753  					      fdt_get_name(blob, src_node,
754  							   NULL));
755  					goto err;
756  				}
757  			}
758  
759  			if (cells_name) {
760  				count = fdtdec_get_int(blob, node, cells_name,
761  						       -1);
762  				if (count == -1) {
763  					debug("%s: could not get %s for %s\n",
764  					      fdt_get_name(blob, src_node,
765  							   NULL),
766  					      cells_name,
767  					      fdt_get_name(blob, node,
768  							   NULL));
769  					goto err;
770  				}
771  			} else {
772  				count = cell_count;
773  			}
774  
775  			/*
776  			 * Make sure that the arguments actually fit in the
777  			 * remaining property data length
778  			 */
779  			if (list + count > list_end) {
780  				debug("%s: arguments longer than property\n",
781  				      fdt_get_name(blob, src_node, NULL));
782  				goto err;
783  			}
784  		}
785  
786  		/*
787  		 * All of the error cases above bail out of the loop, so at
788  		 * this point, the parsing is successful. If the requested
789  		 * index matches, then fill the out_args structure and return,
790  		 * or return -ENOENT for an empty entry.
791  		 */
792  		rc = -ENOENT;
793  		if (cur_index == index) {
794  			if (!phandle)
795  				goto err;
796  
797  			if (out_args) {
798  				int i;
799  
800  				if (count > MAX_PHANDLE_ARGS) {
801  					debug("%s: too many arguments %d\n",
802  					      fdt_get_name(blob, src_node,
803  							   NULL), count);
804  					count = MAX_PHANDLE_ARGS;
805  				}
806  				out_args->node = node;
807  				out_args->args_count = count;
808  				for (i = 0; i < count; i++) {
809  					out_args->args[i] =
810  							be32_to_cpup(list++);
811  				}
812  			}
813  
814  			/* Found it! return success */
815  			return 0;
816  		}
817  
818  		node = -1;
819  		list += count;
820  		cur_index++;
821  	}
822  
823  	/*
824  	 * Result will be one of:
825  	 * -ENOENT : index is for empty phandle
826  	 * -EINVAL : parsing error on data
827  	 * [1..n]  : Number of phandle (count mode; when index = -1)
828  	 */
829  	rc = index < 0 ? cur_index : -ENOENT;
830   err:
831  	return rc;
832  }
833  
834  int fdtdec_get_child_count(const void *blob, int node)
835  {
836  	int subnode;
837  	int num = 0;
838  
839  	fdt_for_each_subnode(blob, subnode, node)
840  		num++;
841  
842  	return num;
843  }
844  
845  int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
846  		u8 *array, int count)
847  {
848  	const u8 *cell;
849  	int err;
850  
851  	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
852  	if (!err)
853  		memcpy(array, cell, count);
854  	return err;
855  }
856  
857  const u8 *fdtdec_locate_byte_array(const void *blob, int node,
858  			     const char *prop_name, int count)
859  {
860  	const u8 *cell;
861  	int err;
862  
863  	cell = get_prop_check_min_len(blob, node, prop_name, count, &err);
864  	if (err)
865  		return NULL;
866  	return cell;
867  }
868  
869  int fdtdec_get_config_int(const void *blob, const char *prop_name,
870  		int default_val)
871  {
872  	int config_node;
873  
874  	debug("%s: %s\n", __func__, prop_name);
875  	config_node = fdt_path_offset(blob, "/config");
876  	if (config_node < 0)
877  		return default_val;
878  	return fdtdec_get_int(blob, config_node, prop_name, default_val);
879  }
880  
881  int fdtdec_get_config_bool(const void *blob, const char *prop_name)
882  {
883  	int config_node;
884  	const void *prop;
885  
886  	debug("%s: %s\n", __func__, prop_name);
887  	config_node = fdt_path_offset(blob, "/config");
888  	if (config_node < 0)
889  		return 0;
890  	prop = fdt_get_property(blob, config_node, prop_name, NULL);
891  
892  	return prop != NULL;
893  }
894  
895  char *fdtdec_get_config_string(const void *blob, const char *prop_name)
896  {
897  	const char *nodep;
898  	int nodeoffset;
899  	int len;
900  
901  	debug("%s: %s\n", __func__, prop_name);
902  	nodeoffset = fdt_path_offset(blob, "/config");
903  	if (nodeoffset < 0)
904  		return NULL;
905  
906  	nodep = fdt_getprop(blob, nodeoffset, prop_name, &len);
907  	if (!nodep)
908  		return NULL;
909  
910  	return (char *)nodep;
911  }
912  
913  int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
914  			 fdt_addr_t *basep, fdt_size_t *sizep)
915  {
916  	const fdt_addr_t *cell;
917  	int len;
918  
919  	debug("%s: %s: %s\n", __func__, fdt_get_name(blob, node, NULL),
920  	      prop_name);
921  	cell = fdt_getprop(blob, node, prop_name, &len);
922  	if (!cell || (len < sizeof(fdt_addr_t) * 2)) {
923  		debug("cell=%p, len=%d\n", cell, len);
924  		return -1;
925  	}
926  
927  	*basep = fdt_addr_to_cpu(*cell);
928  	*sizep = fdt_size_to_cpu(cell[1]);
929  	debug("%s: base=%08lx, size=%lx\n", __func__, (ulong)*basep,
930  	      (ulong)*sizep);
931  
932  	return 0;
933  }
934  
935  /**
936   * Read a flash entry from the fdt
937   *
938   * @param blob		FDT blob
939   * @param node		Offset of node to read
940   * @param name		Name of node being read
941   * @param entry		Place to put offset and size of this node
942   * @return 0 if ok, -ve on error
943   */
944  int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
945  			   struct fmap_entry *entry)
946  {
947  	const char *prop;
948  	u32 reg[2];
949  
950  	if (fdtdec_get_int_array(blob, node, "reg", reg, 2)) {
951  		debug("Node '%s' has bad/missing 'reg' property\n", name);
952  		return -FDT_ERR_NOTFOUND;
953  	}
954  	entry->offset = reg[0];
955  	entry->length = reg[1];
956  	entry->used = fdtdec_get_int(blob, node, "used", entry->length);
957  	prop = fdt_getprop(blob, node, "compress", NULL);
958  	entry->compress_algo = prop && !strcmp(prop, "lzo") ?
959  		FMAP_COMPRESS_LZO : FMAP_COMPRESS_NONE;
960  	prop = fdt_getprop(blob, node, "hash", &entry->hash_size);
961  	entry->hash_algo = prop ? FMAP_HASH_SHA256 : FMAP_HASH_NONE;
962  	entry->hash = (uint8_t *)prop;
963  
964  	return 0;
965  }
966  
967  u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells)
968  {
969  	u64 number = 0;
970  
971  	while (cells--)
972  		number = (number << 32) | fdt32_to_cpu(*ptr++);
973  
974  	return number;
975  }
976  
977  int fdt_get_resource(const void *fdt, int node, const char *property,
978  		     unsigned int index, struct fdt_resource *res)
979  {
980  	const fdt32_t *ptr, *end;
981  	int na, ns, len, parent;
982  	unsigned int i = 0;
983  
984  	parent = fdt_parent_offset(fdt, node);
985  	if (parent < 0)
986  		return parent;
987  
988  	na = fdt_address_cells(fdt, parent);
989  	ns = fdt_size_cells(fdt, parent);
990  
991  	ptr = fdt_getprop(fdt, node, property, &len);
992  	if (!ptr)
993  		return len;
994  
995  	end = ptr + len / sizeof(*ptr);
996  
997  	while (ptr + na + ns <= end) {
998  		if (i == index) {
999  			res->start = res->end = fdtdec_get_number(ptr, na);
1000  			res->end += fdtdec_get_number(&ptr[na], ns) - 1;
1001  			return 0;
1002  		}
1003  
1004  		ptr += na + ns;
1005  		i++;
1006  	}
1007  
1008  	return -FDT_ERR_NOTFOUND;
1009  }
1010  
1011  int fdt_get_named_resource(const void *fdt, int node, const char *property,
1012  			   const char *prop_names, const char *name,
1013  			   struct fdt_resource *res)
1014  {
1015  	int index;
1016  
1017  	index = fdt_find_string(fdt, node, prop_names, name);
1018  	if (index < 0)
1019  		return index;
1020  
1021  	return fdt_get_resource(fdt, node, property, index, res);
1022  }
1023  
1024  int fdtdec_decode_memory_region(const void *blob, int config_node,
1025  				const char *mem_type, const char *suffix,
1026  				fdt_addr_t *basep, fdt_size_t *sizep)
1027  {
1028  	char prop_name[50];
1029  	const char *mem;
1030  	fdt_size_t size, offset_size;
1031  	fdt_addr_t base, offset;
1032  	int node;
1033  
1034  	if (config_node == -1) {
1035  		config_node = fdt_path_offset(blob, "/config");
1036  		if (config_node < 0) {
1037  			debug("%s: Cannot find /config node\n", __func__);
1038  			return -ENOENT;
1039  		}
1040  	}
1041  	if (!suffix)
1042  		suffix = "";
1043  
1044  	snprintf(prop_name, sizeof(prop_name), "%s-memory%s", mem_type,
1045  		 suffix);
1046  	mem = fdt_getprop(blob, config_node, prop_name, NULL);
1047  	if (!mem) {
1048  		debug("%s: No memory type for '%s', using /memory\n", __func__,
1049  		      prop_name);
1050  		mem = "/memory";
1051  	}
1052  
1053  	node = fdt_path_offset(blob, mem);
1054  	if (node < 0) {
1055  		debug("%s: Failed to find node '%s': %s\n", __func__, mem,
1056  		      fdt_strerror(node));
1057  		return -ENOENT;
1058  	}
1059  
1060  	/*
1061  	 * Not strictly correct - the memory may have multiple banks. We just
1062  	 * use the first
1063  	 */
1064  	if (fdtdec_decode_region(blob, node, "reg", &base, &size)) {
1065  		debug("%s: Failed to decode memory region %s\n", __func__,
1066  		      mem);
1067  		return -EINVAL;
1068  	}
1069  
1070  	snprintf(prop_name, sizeof(prop_name), "%s-offset%s", mem_type,
1071  		 suffix);
1072  	if (fdtdec_decode_region(blob, config_node, prop_name, &offset,
1073  				 &offset_size)) {
1074  		debug("%s: Failed to decode memory region '%s'\n", __func__,
1075  		      prop_name);
1076  		return -EINVAL;
1077  	}
1078  
1079  	*basep = base + offset;
1080  	*sizep = offset_size;
1081  
1082  	return 0;
1083  }
1084  
1085  static int decode_timing_property(const void *blob, int node, const char *name,
1086  				  struct timing_entry *result)
1087  {
1088  	int length, ret = 0;
1089  	const u32 *prop;
1090  
1091  	prop = fdt_getprop(blob, node, name, &length);
1092  	if (!prop) {
1093  		debug("%s: could not find property %s\n",
1094  		      fdt_get_name(blob, node, NULL), name);
1095  		return length;
1096  	}
1097  
1098  	if (length == sizeof(u32)) {
1099  		result->typ = fdtdec_get_int(blob, node, name, 0);
1100  		result->min = result->typ;
1101  		result->max = result->typ;
1102  	} else {
1103  		ret = fdtdec_get_int_array(blob, node, name, &result->min, 3);
1104  	}
1105  
1106  	return ret;
1107  }
1108  
1109  int fdtdec_decode_display_timing(const void *blob, int parent, int index,
1110  				 struct display_timing *dt)
1111  {
1112  	int i, node, timings_node;
1113  	u32 val = 0;
1114  	int ret = 0;
1115  
1116  	timings_node = fdt_subnode_offset(blob, parent, "display-timings");
1117  	if (timings_node < 0)
1118  		return timings_node;
1119  
1120  	for (i = 0, node = fdt_first_subnode(blob, timings_node);
1121  	     node > 0 && i != index;
1122  	     node = fdt_next_subnode(blob, node))
1123  		i++;
1124  
1125  	if (node < 0)
1126  		return node;
1127  
1128  	memset(dt, 0, sizeof(*dt));
1129  
1130  	ret |= decode_timing_property(blob, node, "hback-porch",
1131  				      &dt->hback_porch);
1132  	ret |= decode_timing_property(blob, node, "hfront-porch",
1133  				      &dt->hfront_porch);
1134  	ret |= decode_timing_property(blob, node, "hactive", &dt->hactive);
1135  	ret |= decode_timing_property(blob, node, "hsync-len", &dt->hsync_len);
1136  	ret |= decode_timing_property(blob, node, "vback-porch",
1137  				      &dt->vback_porch);
1138  	ret |= decode_timing_property(blob, node, "vfront-porch",
1139  				      &dt->vfront_porch);
1140  	ret |= decode_timing_property(blob, node, "vactive", &dt->vactive);
1141  	ret |= decode_timing_property(blob, node, "vsync-len", &dt->vsync_len);
1142  	ret |= decode_timing_property(blob, node, "clock-frequency",
1143  				      &dt->pixelclock);
1144  
1145  	dt->flags = 0;
1146  	val = fdtdec_get_int(blob, node, "vsync-active", -1);
1147  	if (val != -1) {
1148  		dt->flags |= val ? DISPLAY_FLAGS_VSYNC_HIGH :
1149  				DISPLAY_FLAGS_VSYNC_LOW;
1150  	}
1151  	val = fdtdec_get_int(blob, node, "hsync-active", -1);
1152  	if (val != -1) {
1153  		dt->flags |= val ? DISPLAY_FLAGS_HSYNC_HIGH :
1154  				DISPLAY_FLAGS_HSYNC_LOW;
1155  	}
1156  	val = fdtdec_get_int(blob, node, "de-active", -1);
1157  	if (val != -1) {
1158  		dt->flags |= val ? DISPLAY_FLAGS_DE_HIGH :
1159  				DISPLAY_FLAGS_DE_LOW;
1160  	}
1161  	val = fdtdec_get_int(blob, node, "pixelclk-active", -1);
1162  	if (val != -1) {
1163  		dt->flags |= val ? DISPLAY_FLAGS_PIXDATA_POSEDGE :
1164  				DISPLAY_FLAGS_PIXDATA_NEGEDGE;
1165  	}
1166  
1167  	if (fdtdec_get_bool(blob, node, "interlaced"))
1168  		dt->flags |= DISPLAY_FLAGS_INTERLACED;
1169  	if (fdtdec_get_bool(blob, node, "doublescan"))
1170  		dt->flags |= DISPLAY_FLAGS_DOUBLESCAN;
1171  	if (fdtdec_get_bool(blob, node, "doubleclk"))
1172  		dt->flags |= DISPLAY_FLAGS_DOUBLECLK;
1173  
1174  	return ret;
1175  }
1176  
1177  int fdtdec_setup(void)
1178  {
1179  #if CONFIG_IS_ENABLED(OF_CONTROL)
1180  # ifdef CONFIG_OF_EMBED
1181  	/* Get a pointer to the FDT */
1182  	gd->fdt_blob = __dtb_dt_begin;
1183  # elif defined CONFIG_OF_SEPARATE
1184  #  ifdef CONFIG_SPL_BUILD
1185  	/* FDT is at end of BSS unless it is in a different memory region */
1186  	if (IS_ENABLED(CONFIG_SPL_SEPARATE_BSS))
1187  		gd->fdt_blob = (ulong *)&_image_binary_end;
1188  	else
1189  		gd->fdt_blob = (ulong *)&__bss_end;
1190  #  else
1191  	/* FDT is at end of image */
1192  	gd->fdt_blob = (ulong *)&_end;
1193  #  endif
1194  # elif defined(CONFIG_OF_HOSTFILE)
1195  	if (sandbox_read_fdt_from_file()) {
1196  		puts("Failed to read control FDT\n");
1197  		return -1;
1198  	}
1199  # endif
1200  # ifndef CONFIG_SPL_BUILD
1201  	/* Allow the early environment to override the fdt address */
1202  	gd->fdt_blob = (void *)getenv_ulong("fdtcontroladdr", 16,
1203  						(uintptr_t)gd->fdt_blob);
1204  # endif
1205  #endif
1206  	return fdtdec_prepare_fdt();
1207  }
1208  
1209  #endif /* !USE_HOSTCC */
1210