xref: /rk3399_rockchip-uboot/include/fdtdec.h (revision f9a4c2da72d04e13b05deecb800f232d2948eb85)
1 /*
2  * Copyright (c) 2011 The Chromium OS Authors.
3  * SPDX-License-Identifier:	GPL-2.0+
4  */
5 
6 #ifndef __fdtdec_h
7 #define __fdtdec_h
8 
9 /*
10  * This file contains convenience functions for decoding useful and
11  * enlightening information from FDTs. It is intended to be used by device
12  * drivers and board-specific code within U-Boot. It aims to reduce the
13  * amount of FDT munging required within U-Boot itself, so that driver code
14  * changes to support FDT are minimized.
15  */
16 
17 #include <libfdt.h>
18 #include <pci.h>
19 
20 /*
21  * A typedef for a physical address. Note that fdt data is always big
22  * endian even on a litle endian machine.
23  */
24 #ifdef CONFIG_PHYS_64BIT
25 typedef u64 fdt_addr_t;
26 typedef u64 fdt_size_t;
27 #define FDT_ADDR_T_NONE (-1ULL)
28 #define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
29 #define fdt_size_to_cpu(reg) be64_to_cpu(reg)
30 #else
31 typedef u32 fdt_addr_t;
32 typedef u32 fdt_size_t;
33 #define FDT_ADDR_T_NONE (-1U)
34 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
35 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
36 #endif
37 
38 /* Information obtained about memory from the FDT */
39 struct fdt_memory {
40 	fdt_addr_t start;
41 	fdt_addr_t end;
42 };
43 
44 /*
45  * Information about a resource. start is the first address of the resource
46  * and end is the last address (inclusive). The length of the resource will
47  * be equal to: end - start + 1.
48  */
49 struct fdt_resource {
50 	fdt_addr_t start;
51 	fdt_addr_t end;
52 };
53 
54 enum fdt_pci_space {
55 	FDT_PCI_SPACE_CONFIG = 0,
56 	FDT_PCI_SPACE_IO = 0x01000000,
57 	FDT_PCI_SPACE_MEM32 = 0x02000000,
58 	FDT_PCI_SPACE_MEM64 = 0x03000000,
59 	FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
60 	FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
61 };
62 
63 #define FDT_PCI_ADDR_CELLS	3
64 #define FDT_PCI_SIZE_CELLS	2
65 #define FDT_PCI_REG_SIZE	\
66 	((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
67 
68 /*
69  * The Open Firmware spec defines PCI physical address as follows:
70  *
71  *          bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
72  *
73  * phys.hi  cell:  npt000ss   bbbbbbbb   dddddfff   rrrrrrrr
74  * phys.mid cell:  hhhhhhhh   hhhhhhhh   hhhhhhhh   hhhhhhhh
75  * phys.lo  cell:  llllllll   llllllll   llllllll   llllllll
76  *
77  * where:
78  *
79  * n:        is 0 if the address is relocatable, 1 otherwise
80  * p:        is 1 if addressable region is prefetchable, 0 otherwise
81  * t:        is 1 if the address is aliased (for non-relocatable I/O) below 1MB
82  *           (for Memory), or below 64KB (for relocatable I/O)
83  * ss:       is the space code, denoting the address space
84  * bbbbbbbb: is the 8-bit Bus Number
85  * ddddd:    is the 5-bit Device Number
86  * fff:      is the 3-bit Function Number
87  * rrrrrrrr: is the 8-bit Register Number
88  * hhhhhhhh: is a 32-bit unsigned number
89  * llllllll: is a 32-bit unsigned number
90  */
91 struct fdt_pci_addr {
92 	u32	phys_hi;
93 	u32	phys_mid;
94 	u32	phys_lo;
95 };
96 
97 /**
98  * Compute the size of a resource.
99  *
100  * @param res	the resource to operate on
101  * @return the size of the resource
102  */
103 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
104 {
105 	return res->end - res->start + 1;
106 }
107 
108 /**
109  * Compat types that we know about and for which we might have drivers.
110  * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
111  * within drivers.
112  */
113 enum fdt_compat_id {
114 	COMPAT_UNKNOWN,
115 	COMPAT_NVIDIA_TEGRA20_USB,	/* Tegra20 USB port */
116 	COMPAT_NVIDIA_TEGRA30_USB,	/* Tegra30 USB port */
117 	COMPAT_NVIDIA_TEGRA114_USB,	/* Tegra114 USB port */
118 	COMPAT_NVIDIA_TEGRA114_I2C,	/* Tegra114 I2C w/single clock source */
119 	COMPAT_NVIDIA_TEGRA20_I2C,	/* Tegra20 i2c */
120 	COMPAT_NVIDIA_TEGRA20_DVC,	/* Tegra20 dvc (really just i2c) */
121 	COMPAT_NVIDIA_TEGRA20_EMC,	/* Tegra20 memory controller */
122 	COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
123 	COMPAT_NVIDIA_TEGRA20_KBC,	/* Tegra20 Keyboard */
124 	COMPAT_NVIDIA_TEGRA20_NAND,	/* Tegra2 NAND controller */
125 	COMPAT_NVIDIA_TEGRA20_PWM,	/* Tegra 2 PWM controller */
126 	COMPAT_NVIDIA_TEGRA20_DC,	/* Tegra 2 Display controller */
127 	COMPAT_NVIDIA_TEGRA124_SDMMC,	/* Tegra124 SDMMC controller */
128 	COMPAT_NVIDIA_TEGRA30_SDMMC,	/* Tegra30 SDMMC controller */
129 	COMPAT_NVIDIA_TEGRA20_SDMMC,	/* Tegra20 SDMMC controller */
130 	COMPAT_NVIDIA_TEGRA20_SFLASH,	/* Tegra 2 SPI flash controller */
131 	COMPAT_NVIDIA_TEGRA20_SLINK,	/* Tegra 2 SPI SLINK controller */
132 	COMPAT_NVIDIA_TEGRA114_SPI,	/* Tegra 114 SPI controller */
133 	COMPAT_NVIDIA_TEGRA124_PCIE,	/* Tegra 124 PCIe controller */
134 	COMPAT_NVIDIA_TEGRA30_PCIE,	/* Tegra 30 PCIe controller */
135 	COMPAT_NVIDIA_TEGRA20_PCIE,	/* Tegra 20 PCIe controller */
136 	COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
137 					/* Tegra124 XUSB pad controller */
138 	COMPAT_SMSC_LAN9215,		/* SMSC 10/100 Ethernet LAN9215 */
139 	COMPAT_SAMSUNG_EXYNOS5_SROMC,	/* Exynos5 SROMC */
140 	COMPAT_SAMSUNG_S3C2440_I2C,	/* Exynos I2C Controller */
141 	COMPAT_SAMSUNG_EXYNOS5_SOUND,	/* Exynos Sound */
142 	COMPAT_WOLFSON_WM8994_CODEC,	/* Wolfson WM8994 Sound Codec */
143 	COMPAT_SAMSUNG_EXYNOS_SPI,	/* Exynos SPI */
144 	COMPAT_GOOGLE_CROS_EC,		/* Google CROS_EC Protocol */
145 	COMPAT_GOOGLE_CROS_EC_KEYB,	/* Google CROS_EC Keyboard */
146 	COMPAT_SAMSUNG_EXYNOS_EHCI,	/* Exynos EHCI controller */
147 	COMPAT_SAMSUNG_EXYNOS5_XHCI,	/* Exynos5 XHCI controller */
148 	COMPAT_SAMSUNG_EXYNOS_USB_PHY,	/* Exynos phy controller for usb2.0 */
149 	COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
150 	COMPAT_SAMSUNG_EXYNOS_TMU,	/* Exynos TMU */
151 	COMPAT_SAMSUNG_EXYNOS_FIMD,	/* Exynos Display controller */
152 	COMPAT_SAMSUNG_EXYNOS_MIPI_DSI,	/* Exynos mipi dsi */
153 	COMPAT_SAMSUNG_EXYNOS5_DP,	/* Exynos Display port controller */
154 	COMPAT_SAMSUNG_EXYNOS_DWMMC,	/* Exynos DWMMC controller */
155 	COMPAT_SAMSUNG_EXYNOS_MMC,	/* Exynos MMC controller */
156 	COMPAT_SAMSUNG_EXYNOS_SERIAL,	/* Exynos UART */
157 	COMPAT_MAXIM_MAX77686_PMIC,	/* MAX77686 PMIC */
158 	COMPAT_GENERIC_SPI_FLASH,	/* Generic SPI Flash chip */
159 	COMPAT_MAXIM_98095_CODEC,	/* MAX98095 Codec */
160 	COMPAT_INFINEON_SLB9635_TPM,	/* Infineon SLB9635 TPM */
161 	COMPAT_INFINEON_SLB9645_TPM,	/* Infineon SLB9645 TPM */
162 	COMPAT_SAMSUNG_EXYNOS5_I2C,	/* Exynos5 High Speed I2C Controller */
163 	COMPAT_SANDBOX_HOST_EMULATION,	/* Sandbox emulation of a function */
164 	COMPAT_SANDBOX_LCD_SDL,		/* Sandbox LCD emulation with SDL */
165 	COMPAT_TI_TPS65090,		/* Texas Instrument TPS65090 */
166 	COMPAT_NXP_PTN3460,		/* NXP PTN3460 DP/LVDS bridge */
167 	COMPAT_SAMSUNG_EXYNOS_SYSMMU,	/* Exynos sysmmu */
168 	COMPAT_PARADE_PS8625,		/* Parade PS8622 EDP->LVDS bridge */
169 	COMPAT_INTEL_LPC,		/* Intel Low Pin Count I/F */
170 	COMPAT_INTEL_MICROCODE,		/* Intel microcode update */
171 	COMPAT_MEMORY_SPD,		/* Memory SPD information */
172 	COMPAT_INTEL_PANTHERPOINT_AHCI,	/* Intel Pantherpoint AHCI */
173 	COMPAT_INTEL_MODEL_206AX,	/* Intel Model 206AX CPU */
174 	COMPAT_INTEL_GMA,		/* Intel Graphics Media Accelerator */
175 	COMPAT_AMS_AS3722,		/* AMS AS3722 PMIC */
176 	COMPAT_INTEL_ICH_SPI,		/* Intel ICH7/9 SPI controller */
177 
178 	COMPAT_COUNT,
179 };
180 
181 #define MAX_PHANDLE_ARGS 16
182 struct fdtdec_phandle_args {
183 	int node;
184 	int args_count;
185 	uint32_t args[MAX_PHANDLE_ARGS];
186 };
187 
188 /**
189  * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
190  *
191  * This function is useful to parse lists of phandles and their arguments.
192  *
193  * Example:
194  *
195  * phandle1: node1 {
196  *	#list-cells = <2>;
197  * }
198  *
199  * phandle2: node2 {
200  *	#list-cells = <1>;
201  * }
202  *
203  * node3 {
204  *	list = <&phandle1 1 2 &phandle2 3>;
205  * }
206  *
207  * To get a device_node of the `node2' node you may call this:
208  * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
209  *				  &args);
210  *
211  * (This function is a modified version of __of_parse_phandle_with_args() from
212  * Linux 3.18)
213  *
214  * @blob:	Pointer to device tree
215  * @src_node:	Offset of device tree node containing a list
216  * @list_name:	property name that contains a list
217  * @cells_name:	property name that specifies the phandles' arguments count,
218  *		or NULL to use @cells_count
219  * @cells_count: Cell count to use if @cells_name is NULL
220  * @index:	index of a phandle to parse out
221  * @out_args:	optional pointer to output arguments structure (will be filled)
222  * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
223  *	@list_name does not exist, a phandle was not found, @cells_name
224  *	could not be found, the arguments were truncated or there were too
225  *	many arguments.
226  *
227  */
228 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
229 				   const char *list_name,
230 				   const char *cells_name,
231 				   int cell_count, int index,
232 				   struct fdtdec_phandle_args *out_args);
233 
234 /**
235  * Find the next numbered alias for a peripheral. This is used to enumerate
236  * all the peripherals of a certain type.
237  *
238  * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
239  * this function will return a pointer to the node the alias points to, and
240  * then update *upto to 1. Next time you call this function, the next node
241  * will be returned.
242  *
243  * All nodes returned will match the compatible ID, as it is assumed that
244  * all peripherals use the same driver.
245  *
246  * @param blob		FDT blob to use
247  * @param name		Root name of alias to search for
248  * @param id		Compatible ID to look for
249  * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
250  */
251 int fdtdec_next_alias(const void *blob, const char *name,
252 		enum fdt_compat_id id, int *upto);
253 
254 /**
255  * Find the compatible ID for a given node.
256  *
257  * Generally each node has at least one compatible string attached to it.
258  * This function looks through our list of known compatible strings and
259  * returns the corresponding ID which matches the compatible string.
260  *
261  * @param blob		FDT blob to use
262  * @param node		Node containing compatible string to find
263  * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
264  */
265 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
266 
267 /**
268  * Find the next compatible node for a peripheral.
269  *
270  * Do the first call with node = 0. This function will return a pointer to
271  * the next compatible node. Next time you call this function, pass the
272  * value returned, and the next node will be provided.
273  *
274  * @param blob		FDT blob to use
275  * @param node		Start node for search
276  * @param id		Compatible ID to look for (enum fdt_compat_id)
277  * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
278  */
279 int fdtdec_next_compatible(const void *blob, int node,
280 		enum fdt_compat_id id);
281 
282 /**
283  * Find the next compatible subnode for a peripheral.
284  *
285  * Do the first call with node set to the parent and depth = 0. This
286  * function will return the offset of the next compatible node. Next time
287  * you call this function, pass the node value returned last time, with
288  * depth unchanged, and the next node will be provided.
289  *
290  * @param blob		FDT blob to use
291  * @param node		Start node for search
292  * @param id		Compatible ID to look for (enum fdt_compat_id)
293  * @param depthp	Current depth (set to 0 before first call)
294  * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
295  */
296 int fdtdec_next_compatible_subnode(const void *blob, int node,
297 		enum fdt_compat_id id, int *depthp);
298 
299 /**
300  * Look up an address property in a node and return it as an address.
301  * The property must hold either one address with no trailing data or
302  * one address with a length. This is only tested on 32-bit machines.
303  *
304  * @param blob	FDT blob
305  * @param node	node to examine
306  * @param prop_name	name of property to find
307  * @return address, if found, or FDT_ADDR_T_NONE if not
308  */
309 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
310 		const char *prop_name);
311 
312 /**
313  * Look up an address property in a node and return it as an address.
314  * The property must hold one address with a length. This is only tested
315  * on 32-bit machines.
316  *
317  * @param blob	FDT blob
318  * @param node	node to examine
319  * @param prop_name	name of property to find
320  * @return address, if found, or FDT_ADDR_T_NONE if not
321  */
322 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
323 		const char *prop_name, fdt_size_t *sizep);
324 
325 /**
326  * Look at an address property in a node and return the pci address which
327  * corresponds to the given type in the form of fdt_pci_addr.
328  * The property must hold one fdt_pci_addr with a lengh.
329  *
330  * @param blob		FDT blob
331  * @param node		node to examine
332  * @param type		pci address type (FDT_PCI_SPACE_xxx)
333  * @param prop_name	name of property to find
334  * @param addr		returns pci address in the form of fdt_pci_addr
335  * @return 0 if ok, negative on error
336  */
337 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
338 		const char *prop_name, struct fdt_pci_addr *addr);
339 
340 /**
341  * Look at the compatible property of a device node that represents a PCI
342  * device and extract pci vendor id and device id from it.
343  *
344  * @param blob		FDT blob
345  * @param node		node to examine
346  * @param vendor	vendor id of the pci device
347  * @param device	device id of the pci device
348  * @return 0 if ok, negative on error
349  */
350 int fdtdec_get_pci_vendev(const void *blob, int node,
351 		u16 *vendor, u16 *device);
352 
353 /**
354  * Look at the pci address of a device node that represents a PCI device
355  * and parse the bus, device and function number from it.
356  *
357  * @param blob		FDT blob
358  * @param node		node to examine
359  * @param addr		pci address in the form of fdt_pci_addr
360  * @param bdf		returns bus, device, function triplet
361  * @return 0 if ok, negative on error
362  */
363 int fdtdec_get_pci_bdf(const void *blob, int node,
364 		struct fdt_pci_addr *addr, pci_dev_t *bdf);
365 
366 /**
367  * Look at the pci address of a device node that represents a PCI device
368  * and return base address of the pci device's registers.
369  *
370  * @param blob		FDT blob
371  * @param node		node to examine
372  * @param addr		pci address in the form of fdt_pci_addr
373  * @param bar		returns base address of the pci device's registers
374  * @return 0 if ok, negative on error
375  */
376 int fdtdec_get_pci_bar32(const void *blob, int node,
377 		struct fdt_pci_addr *addr, u32 *bar);
378 
379 /**
380  * Look up a 32-bit integer property in a node and return it. The property
381  * must have at least 4 bytes of data. The value of the first cell is
382  * returned.
383  *
384  * @param blob	FDT blob
385  * @param node	node to examine
386  * @param prop_name	name of property to find
387  * @param default_val	default value to return if the property is not found
388  * @return integer value, if found, or default_val if not
389  */
390 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
391 		s32 default_val);
392 
393 /**
394  * Look up a 64-bit integer property in a node and return it. The property
395  * must have at least 8 bytes of data (2 cells). The first two cells are
396  * concatenated to form a 8 bytes value, where the first cell is top half and
397  * the second cell is bottom half.
398  *
399  * @param blob	FDT blob
400  * @param node	node to examine
401  * @param prop_name	name of property to find
402  * @param default_val	default value to return if the property is not found
403  * @return integer value, if found, or default_val if not
404  */
405 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
406 		uint64_t default_val);
407 
408 /**
409  * Checks whether a node is enabled.
410  * This looks for a 'status' property. If this exists, then returns 1 if
411  * the status is 'ok' and 0 otherwise. If there is no status property,
412  * it returns 1 on the assumption that anything mentioned should be enabled
413  * by default.
414  *
415  * @param blob	FDT blob
416  * @param node	node to examine
417  * @return integer value 0 (not enabled) or 1 (enabled)
418  */
419 int fdtdec_get_is_enabled(const void *blob, int node);
420 
421 /**
422  * Make sure we have a valid fdt available to control U-Boot.
423  *
424  * If not, a message is printed to the console if the console is ready.
425  *
426  * @return 0 if all ok, -1 if not
427  */
428 int fdtdec_prepare_fdt(void);
429 
430 /**
431  * Checks that we have a valid fdt available to control U-Boot.
432 
433  * However, if not then for the moment nothing is done, since this function
434  * is called too early to panic().
435  *
436  * @returns 0
437  */
438 int fdtdec_check_fdt(void);
439 
440 /**
441  * Find the nodes for a peripheral and return a list of them in the correct
442  * order. This is used to enumerate all the peripherals of a certain type.
443  *
444  * To use this, optionally set up a /aliases node with alias properties for
445  * a peripheral. For example, for usb you could have:
446  *
447  * aliases {
448  *		usb0 = "/ehci@c5008000";
449  *		usb1 = "/ehci@c5000000";
450  * };
451  *
452  * Pass "usb" as the name to this function and will return a list of two
453  * nodes offsets: /ehci@c5008000 and ehci@c5000000.
454  *
455  * All nodes returned will match the compatible ID, as it is assumed that
456  * all peripherals use the same driver.
457  *
458  * If no alias node is found, then the node list will be returned in the
459  * order found in the fdt. If the aliases mention a node which doesn't
460  * exist, then this will be ignored. If nodes are found with no aliases,
461  * they will be added in any order.
462  *
463  * If there is a gap in the aliases, then this function return a 0 node at
464  * that position. The return value will also count these gaps.
465  *
466  * This function checks node properties and will not return nodes which are
467  * marked disabled (status = "disabled").
468  *
469  * @param blob		FDT blob to use
470  * @param name		Root name of alias to search for
471  * @param id		Compatible ID to look for
472  * @param node_list	Place to put list of found nodes
473  * @param maxcount	Maximum number of nodes to find
474  * @return number of nodes found on success, FTD_ERR_... on error
475  */
476 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
477 			enum fdt_compat_id id, int *node_list, int maxcount);
478 
479 /*
480  * This function is similar to fdtdec_find_aliases_for_id() except that it
481  * adds to the node_list that is passed in. Any 0 elements are considered
482  * available for allocation - others are considered already used and are
483  * skipped.
484  *
485  * You can use this by calling fdtdec_find_aliases_for_id() with an
486  * uninitialised array, then setting the elements that are returned to -1,
487  * say, then calling this function, perhaps with a different compat id.
488  * Any elements you get back that are >0 are new nodes added by the call
489  * to this function.
490  *
491  * Note that if you have some nodes with aliases and some without, you are
492  * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
493  * one compat_id may fill in positions for which you have aliases defined
494  * for another compat_id. When you later call *this* function with the second
495  * compat_id, the alias positions may already be used. A debug warning may
496  * be generated in this case, but it is safest to define aliases for all
497  * nodes when you care about the ordering.
498  */
499 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
500 			enum fdt_compat_id id, int *node_list, int maxcount);
501 
502 /**
503  * Get the alias sequence number of a node
504  *
505  * This works out whether a node is pointed to by an alias, and if so, the
506  * sequence number of that alias. Aliases are of the form <base><num> where
507  * <num> is the sequence number. For example spi2 would be sequence number
508  * 2.
509  *
510  * @param blob		Device tree blob (if NULL, then error is returned)
511  * @param base		Base name for alias (before the underscore)
512  * @param node		Node to look up
513  * @param seqp		This is set to the sequence number if one is found,
514  *			but otherwise the value is left alone
515  * @return 0 if a sequence was found, -ve if not
516  */
517 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
518 			 int *seqp);
519 
520 /**
521  * Get the offset of the given chosen node
522  *
523  * This looks up a property in /chosen containing the path to another node,
524  * then finds the offset of that node.
525  *
526  * @param blob		Device tree blob (if NULL, then error is returned)
527  * @param name		Property name, e.g. "stdout-path"
528  * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
529  */
530 int fdtdec_get_chosen_node(const void *blob, const char *name);
531 
532 /*
533  * Get the name for a compatible ID
534  *
535  * @param id		Compatible ID to look for
536  * @return compatible string for that id
537  */
538 const char *fdtdec_get_compatible(enum fdt_compat_id id);
539 
540 /* Look up a phandle and follow it to its node. Then return the offset
541  * of that node.
542  *
543  * @param blob		FDT blob
544  * @param node		node to examine
545  * @param prop_name	name of property to find
546  * @return node offset if found, -ve error code on error
547  */
548 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
549 
550 /**
551  * Look up a property in a node and return its contents in an integer
552  * array of given length. The property must have at least enough data for
553  * the array (4*count bytes). It may have more, but this will be ignored.
554  *
555  * @param blob		FDT blob
556  * @param node		node to examine
557  * @param prop_name	name of property to find
558  * @param array		array to fill with data
559  * @param count		number of array elements
560  * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
561  *		or -FDT_ERR_BADLAYOUT if not enough data
562  */
563 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
564 		u32 *array, int count);
565 
566 /**
567  * Look up a property in a node and return its contents in an integer
568  * array of given length. The property must exist but may have less data that
569  * expected (4*count bytes). It may have more, but this will be ignored.
570  *
571  * @param blob		FDT blob
572  * @param node		node to examine
573  * @param prop_name	name of property to find
574  * @param array		array to fill with data
575  * @param count		number of array elements
576  * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
577  *		property is not found
578  */
579 int fdtdec_get_int_array_count(const void *blob, int node,
580 			       const char *prop_name, u32 *array, int count);
581 
582 /**
583  * Look up a property in a node and return a pointer to its contents as a
584  * unsigned int array of given length. The property must have at least enough
585  * data for the array ('count' cells). It may have more, but this will be
586  * ignored. The data is not copied.
587  *
588  * Note that you must access elements of the array with fdt32_to_cpu(),
589  * since the elements will be big endian even on a little endian machine.
590  *
591  * @param blob		FDT blob
592  * @param node		node to examine
593  * @param prop_name	name of property to find
594  * @param count		number of array elements
595  * @return pointer to array if found, or NULL if the property is not
596  *		found or there is not enough data
597  */
598 const u32 *fdtdec_locate_array(const void *blob, int node,
599 			       const char *prop_name, int count);
600 
601 /**
602  * Look up a boolean property in a node and return it.
603  *
604  * A boolean properly is true if present in the device tree and false if not
605  * present, regardless of its value.
606  *
607  * @param blob	FDT blob
608  * @param node	node to examine
609  * @param prop_name	name of property to find
610  * @return 1 if the properly is present; 0 if it isn't present
611  */
612 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
613 
614 /**
615  * Look in the FDT for a config item with the given name and return its value
616  * as a 32-bit integer. The property must have at least 4 bytes of data. The
617  * value of the first cell is returned.
618  *
619  * @param blob		FDT blob to use
620  * @param prop_name	Node property name
621  * @param default_val	default value to return if the property is not found
622  * @return integer value, if found, or default_val if not
623  */
624 int fdtdec_get_config_int(const void *blob, const char *prop_name,
625 		int default_val);
626 
627 /**
628  * Look in the FDT for a config item with the given name
629  * and return whether it exists.
630  *
631  * @param blob		FDT blob
632  * @param prop_name	property name to look up
633  * @return 1, if it exists, or 0 if not
634  */
635 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
636 
637 /**
638  * Look in the FDT for a config item with the given name and return its value
639  * as a string.
640  *
641  * @param blob          FDT blob
642  * @param prop_name     property name to look up
643  * @returns property string, NULL on error.
644  */
645 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
646 
647 /*
648  * Look up a property in a node and return its contents in a byte
649  * array of given length. The property must have at least enough data for
650  * the array (count bytes). It may have more, but this will be ignored.
651  *
652  * @param blob		FDT blob
653  * @param node		node to examine
654  * @param prop_name	name of property to find
655  * @param array		array to fill with data
656  * @param count		number of array elements
657  * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
658  *		or -FDT_ERR_BADLAYOUT if not enough data
659  */
660 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
661 		u8 *array, int count);
662 
663 /**
664  * Look up a property in a node and return a pointer to its contents as a
665  * byte array of given length. The property must have at least enough data
666  * for the array (count bytes). It may have more, but this will be ignored.
667  * The data is not copied.
668  *
669  * @param blob		FDT blob
670  * @param node		node to examine
671  * @param prop_name	name of property to find
672  * @param count		number of array elements
673  * @return pointer to byte array if found, or NULL if the property is not
674  *		found or there is not enough data
675  */
676 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
677 			     const char *prop_name, int count);
678 
679 /**
680  * Look up a property in a node which contains a memory region address and
681  * size. Then return a pointer to this address.
682  *
683  * The property must hold one address with a length. This is only tested on
684  * 32-bit machines.
685  *
686  * @param blob		FDT blob
687  * @param node		node to examine
688  * @param prop_name	name of property to find
689  * @param basep		Returns base address of region
690  * @param size		Returns size of region
691  * @return 0 if ok, -1 on error (property not found)
692  */
693 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
694 			 fdt_addr_t *basep, fdt_size_t *sizep);
695 
696 enum fmap_compress_t {
697 	FMAP_COMPRESS_NONE,
698 	FMAP_COMPRESS_LZO,
699 };
700 
701 enum fmap_hash_t {
702 	FMAP_HASH_NONE,
703 	FMAP_HASH_SHA1,
704 	FMAP_HASH_SHA256,
705 };
706 
707 /* A flash map entry, containing an offset and length */
708 struct fmap_entry {
709 	uint32_t offset;
710 	uint32_t length;
711 	uint32_t used;			/* Number of bytes used in region */
712 	enum fmap_compress_t compress_algo;	/* Compression type */
713 	enum fmap_hash_t hash_algo;		/* Hash algorithm */
714 	const uint8_t *hash;			/* Hash value */
715 	int hash_size;				/* Hash size */
716 };
717 
718 /**
719  * Read a flash entry from the fdt
720  *
721  * @param blob		FDT blob
722  * @param node		Offset of node to read
723  * @param name		Name of node being read
724  * @param entry		Place to put offset and size of this node
725  * @return 0 if ok, -ve on error
726  */
727 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
728 			   struct fmap_entry *entry);
729 
730 /**
731  * Obtain an indexed resource from a device property.
732  *
733  * @param fdt		FDT blob
734  * @param node		node to examine
735  * @param property	name of the property to parse
736  * @param index		index of the resource to retrieve
737  * @param res		returns the resource
738  * @return 0 if ok, negative on error
739  */
740 int fdt_get_resource(const void *fdt, int node, const char *property,
741 		     unsigned int index, struct fdt_resource *res);
742 
743 /**
744  * Obtain a named resource from a device property.
745  *
746  * Look up the index of the name in a list of strings and return the resource
747  * at that index.
748  *
749  * @param fdt		FDT blob
750  * @param node		node to examine
751  * @param property	name of the property to parse
752  * @param prop_names	name of the property containing the list of names
753  * @param name		the name of the entry to look up
754  * @param res		returns the resource
755  */
756 int fdt_get_named_resource(const void *fdt, int node, const char *property,
757 			   const char *prop_names, const char *name,
758 			   struct fdt_resource *res);
759 
760 /**
761  * Decode a named region within a memory bank of a given type.
762  *
763  * This function handles selection of a memory region. The region is
764  * specified as an offset/size within a particular type of memory.
765  *
766  * The properties used are:
767  *
768  *	<mem_type>-memory<suffix> for the name of the memory bank
769  *	<mem_type>-offset<suffix> for the offset in that bank
770  *
771  * The property value must have an offset and a size. The function checks
772  * that the region is entirely within the memory bank.5
773  *
774  * @param blob		FDT blob
775  * @param node		Node containing the properties (-1 for /config)
776  * @param mem_type	Type of memory to use, which is a name, such as
777  *			"u-boot" or "kernel".
778  * @param suffix	String to append to the memory/offset
779  *			property names
780  * @param basep		Returns base of region
781  * @param sizep		Returns size of region
782  * @return 0 if OK, -ive on error
783  */
784 int fdtdec_decode_memory_region(const void *blob, int node,
785 				const char *mem_type, const char *suffix,
786 				fdt_addr_t *basep, fdt_size_t *sizep);
787 #endif
788