xref: /openbmc/u-boot/include/fdtdec.h (revision 9038cd53)
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 #ifdef CONFIG_OF_CONTROL
45 # if defined(CONFIG_SPL_BUILD) && defined(SPL_DISABLE_OF_CONTROL)
46 #  define OF_CONTROL 0
47 # else
48 #  define OF_CONTROL 1
49 # endif
50 #else
51 # define OF_CONTROL 0
52 #endif
53 
54 /*
55  * Information about a resource. start is the first address of the resource
56  * and end is the last address (inclusive). The length of the resource will
57  * be equal to: end - start + 1.
58  */
59 struct fdt_resource {
60 	fdt_addr_t start;
61 	fdt_addr_t end;
62 };
63 
64 enum fdt_pci_space {
65 	FDT_PCI_SPACE_CONFIG = 0,
66 	FDT_PCI_SPACE_IO = 0x01000000,
67 	FDT_PCI_SPACE_MEM32 = 0x02000000,
68 	FDT_PCI_SPACE_MEM64 = 0x03000000,
69 	FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
70 	FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
71 };
72 
73 #define FDT_PCI_ADDR_CELLS	3
74 #define FDT_PCI_SIZE_CELLS	2
75 #define FDT_PCI_REG_SIZE	\
76 	((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
77 
78 /*
79  * The Open Firmware spec defines PCI physical address as follows:
80  *
81  *          bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
82  *
83  * phys.hi  cell:  npt000ss   bbbbbbbb   dddddfff   rrrrrrrr
84  * phys.mid cell:  hhhhhhhh   hhhhhhhh   hhhhhhhh   hhhhhhhh
85  * phys.lo  cell:  llllllll   llllllll   llllllll   llllllll
86  *
87  * where:
88  *
89  * n:        is 0 if the address is relocatable, 1 otherwise
90  * p:        is 1 if addressable region is prefetchable, 0 otherwise
91  * t:        is 1 if the address is aliased (for non-relocatable I/O) below 1MB
92  *           (for Memory), or below 64KB (for relocatable I/O)
93  * ss:       is the space code, denoting the address space
94  * bbbbbbbb: is the 8-bit Bus Number
95  * ddddd:    is the 5-bit Device Number
96  * fff:      is the 3-bit Function Number
97  * rrrrrrrr: is the 8-bit Register Number
98  * hhhhhhhh: is a 32-bit unsigned number
99  * llllllll: is a 32-bit unsigned number
100  */
101 struct fdt_pci_addr {
102 	u32	phys_hi;
103 	u32	phys_mid;
104 	u32	phys_lo;
105 };
106 
107 /**
108  * Compute the size of a resource.
109  *
110  * @param res	the resource to operate on
111  * @return the size of the resource
112  */
113 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
114 {
115 	return res->end - res->start + 1;
116 }
117 
118 /**
119  * Compat types that we know about and for which we might have drivers.
120  * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
121  * within drivers.
122  */
123 enum fdt_compat_id {
124 	COMPAT_UNKNOWN,
125 	COMPAT_NVIDIA_TEGRA20_USB,	/* Tegra20 USB port */
126 	COMPAT_NVIDIA_TEGRA30_USB,	/* Tegra30 USB port */
127 	COMPAT_NVIDIA_TEGRA114_USB,	/* Tegra114 USB port */
128 	COMPAT_NVIDIA_TEGRA20_EMC,	/* Tegra20 memory controller */
129 	COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
130 	COMPAT_NVIDIA_TEGRA20_KBC,	/* Tegra20 Keyboard */
131 	COMPAT_NVIDIA_TEGRA20_NAND,	/* Tegra2 NAND controller */
132 	COMPAT_NVIDIA_TEGRA20_PWM,	/* Tegra 2 PWM controller */
133 	COMPAT_NVIDIA_TEGRA124_DC,	/* Tegra 124 Display controller */
134 	COMPAT_NVIDIA_TEGRA124_SOR,	/* Tegra 124 Serial Output Resource */
135 	COMPAT_NVIDIA_TEGRA124_PMC,	/* Tegra 124 power mgmt controller */
136 	COMPAT_NVIDIA_TEGRA20_DC,	/* Tegra 2 Display controller */
137 	COMPAT_NVIDIA_TEGRA124_SDMMC,	/* Tegra124 SDMMC controller */
138 	COMPAT_NVIDIA_TEGRA30_SDMMC,	/* Tegra30 SDMMC controller */
139 	COMPAT_NVIDIA_TEGRA20_SDMMC,	/* Tegra20 SDMMC controller */
140 	COMPAT_NVIDIA_TEGRA124_PCIE,	/* Tegra 124 PCIe controller */
141 	COMPAT_NVIDIA_TEGRA30_PCIE,	/* Tegra 30 PCIe controller */
142 	COMPAT_NVIDIA_TEGRA20_PCIE,	/* Tegra 20 PCIe controller */
143 	COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
144 					/* Tegra124 XUSB pad controller */
145 	COMPAT_SMSC_LAN9215,		/* SMSC 10/100 Ethernet LAN9215 */
146 	COMPAT_SAMSUNG_EXYNOS5_SROMC,	/* Exynos5 SROMC */
147 	COMPAT_SAMSUNG_S3C2440_I2C,	/* Exynos I2C Controller */
148 	COMPAT_SAMSUNG_EXYNOS5_SOUND,	/* Exynos Sound */
149 	COMPAT_WOLFSON_WM8994_CODEC,	/* Wolfson WM8994 Sound Codec */
150 	COMPAT_GOOGLE_CROS_EC_KEYB,	/* Google CROS_EC Keyboard */
151 	COMPAT_SAMSUNG_EXYNOS_USB_PHY,	/* Exynos phy controller for usb2.0 */
152 	COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
153 	COMPAT_SAMSUNG_EXYNOS_TMU,	/* Exynos TMU */
154 	COMPAT_SAMSUNG_EXYNOS_FIMD,	/* Exynos Display controller */
155 	COMPAT_SAMSUNG_EXYNOS_MIPI_DSI,	/* Exynos mipi dsi */
156 	COMPAT_SAMSUNG_EXYNOS5_DP,	/* Exynos Display port controller */
157 	COMPAT_SAMSUNG_EXYNOS_DWMMC,	/* Exynos DWMMC controller */
158 	COMPAT_SAMSUNG_EXYNOS_MMC,	/* Exynos MMC controller */
159 	COMPAT_SAMSUNG_EXYNOS_SERIAL,	/* Exynos UART */
160 	COMPAT_MAXIM_MAX77686_PMIC,	/* MAX77686 PMIC */
161 	COMPAT_GENERIC_SPI_FLASH,	/* Generic SPI Flash chip */
162 	COMPAT_MAXIM_98095_CODEC,	/* MAX98095 Codec */
163 	COMPAT_INFINEON_SLB9635_TPM,	/* Infineon SLB9635 TPM */
164 	COMPAT_INFINEON_SLB9645_TPM,	/* Infineon SLB9645 TPM */
165 	COMPAT_SAMSUNG_EXYNOS5_I2C,	/* Exynos5 High Speed I2C Controller */
166 	COMPAT_SANDBOX_LCD_SDL,		/* Sandbox LCD emulation with SDL */
167 	COMPAT_TI_TPS65090,		/* Texas Instrument TPS65090 */
168 	COMPAT_NXP_PTN3460,		/* NXP PTN3460 DP/LVDS bridge */
169 	COMPAT_SAMSUNG_EXYNOS_SYSMMU,	/* Exynos sysmmu */
170 	COMPAT_PARADE_PS8625,		/* Parade PS8622 EDP->LVDS bridge */
171 	COMPAT_INTEL_MICROCODE,		/* Intel microcode update */
172 	COMPAT_MEMORY_SPD,		/* Memory SPD information */
173 	COMPAT_INTEL_PANTHERPOINT_AHCI,	/* Intel Pantherpoint AHCI */
174 	COMPAT_INTEL_MODEL_206AX,	/* Intel Model 206AX CPU */
175 	COMPAT_INTEL_GMA,		/* Intel Graphics Media Accelerator */
176 	COMPAT_AMS_AS3722,		/* AMS AS3722 PMIC */
177 	COMPAT_INTEL_ICH_SPI,		/* Intel ICH7/9 SPI controller */
178 	COMPAT_INTEL_QRK_MRC,		/* Intel Quark MRC */
179 	COMPAT_SOCIONEXT_XHCI,		/* Socionext UniPhier xHCI */
180 	COMPAT_INTEL_PCH,		/* Intel PCH */
181 
182 	COMPAT_COUNT,
183 };
184 
185 #define MAX_PHANDLE_ARGS 16
186 struct fdtdec_phandle_args {
187 	int node;
188 	int args_count;
189 	uint32_t args[MAX_PHANDLE_ARGS];
190 };
191 
192 /**
193  * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
194  *
195  * This function is useful to parse lists of phandles and their arguments.
196  *
197  * Example:
198  *
199  * phandle1: node1 {
200  *	#list-cells = <2>;
201  * }
202  *
203  * phandle2: node2 {
204  *	#list-cells = <1>;
205  * }
206  *
207  * node3 {
208  *	list = <&phandle1 1 2 &phandle2 3>;
209  * }
210  *
211  * To get a device_node of the `node2' node you may call this:
212  * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
213  *				  &args);
214  *
215  * (This function is a modified version of __of_parse_phandle_with_args() from
216  * Linux 3.18)
217  *
218  * @blob:	Pointer to device tree
219  * @src_node:	Offset of device tree node containing a list
220  * @list_name:	property name that contains a list
221  * @cells_name:	property name that specifies the phandles' arguments count,
222  *		or NULL to use @cells_count
223  * @cells_count: Cell count to use if @cells_name is NULL
224  * @index:	index of a phandle to parse out
225  * @out_args:	optional pointer to output arguments structure (will be filled)
226  * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
227  *	@list_name does not exist, a phandle was not found, @cells_name
228  *	could not be found, the arguments were truncated or there were too
229  *	many arguments.
230  *
231  */
232 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
233 				   const char *list_name,
234 				   const char *cells_name,
235 				   int cell_count, int index,
236 				   struct fdtdec_phandle_args *out_args);
237 
238 /**
239  * Find the next numbered alias for a peripheral. This is used to enumerate
240  * all the peripherals of a certain type.
241  *
242  * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
243  * this function will return a pointer to the node the alias points to, and
244  * then update *upto to 1. Next time you call this function, the next node
245  * will be returned.
246  *
247  * All nodes returned will match the compatible ID, as it is assumed that
248  * all peripherals use the same driver.
249  *
250  * @param blob		FDT blob to use
251  * @param name		Root name of alias to search for
252  * @param id		Compatible ID to look for
253  * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
254  */
255 int fdtdec_next_alias(const void *blob, const char *name,
256 		enum fdt_compat_id id, int *upto);
257 
258 /**
259  * Find the compatible ID for a given node.
260  *
261  * Generally each node has at least one compatible string attached to it.
262  * This function looks through our list of known compatible strings and
263  * returns the corresponding ID which matches the compatible string.
264  *
265  * @param blob		FDT blob to use
266  * @param node		Node containing compatible string to find
267  * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
268  */
269 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
270 
271 /**
272  * Find the next compatible node for a peripheral.
273  *
274  * Do the first call with node = 0. This function will return a pointer to
275  * the next compatible node. Next time you call this function, pass the
276  * value returned, and the next node will be provided.
277  *
278  * @param blob		FDT blob to use
279  * @param node		Start node for search
280  * @param id		Compatible ID to look for (enum fdt_compat_id)
281  * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
282  */
283 int fdtdec_next_compatible(const void *blob, int node,
284 		enum fdt_compat_id id);
285 
286 /**
287  * Find the next compatible subnode for a peripheral.
288  *
289  * Do the first call with node set to the parent and depth = 0. This
290  * function will return the offset of the next compatible node. Next time
291  * you call this function, pass the node value returned last time, with
292  * depth unchanged, and the next node will be provided.
293  *
294  * @param blob		FDT blob to use
295  * @param node		Start node for search
296  * @param id		Compatible ID to look for (enum fdt_compat_id)
297  * @param depthp	Current depth (set to 0 before first call)
298  * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
299  */
300 int fdtdec_next_compatible_subnode(const void *blob, int node,
301 		enum fdt_compat_id id, int *depthp);
302 
303 /**
304  * Look up an address property in a node and return it as an address.
305  * The property must hold either one address with no trailing data or
306  * one address with a length. This is only tested on 32-bit machines.
307  *
308  * @param blob	FDT blob
309  * @param node	node to examine
310  * @param prop_name	name of property to find
311  * @return address, if found, or FDT_ADDR_T_NONE if not
312  */
313 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
314 		const char *prop_name);
315 
316 /**
317  * Look up an address property in a node and return it as an address.
318  * The property must hold one address with a length. This is only tested
319  * on 32-bit machines.
320  *
321  * @param blob	FDT blob
322  * @param node	node to examine
323  * @param prop_name	name of property to find
324  * @return address, if found, or FDT_ADDR_T_NONE if not
325  */
326 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
327 		const char *prop_name, fdt_size_t *sizep);
328 
329 /**
330  * Look at an address property in a node and return the pci address which
331  * corresponds to the given type in the form of fdt_pci_addr.
332  * The property must hold one fdt_pci_addr with a lengh.
333  *
334  * @param blob		FDT blob
335  * @param node		node to examine
336  * @param type		pci address type (FDT_PCI_SPACE_xxx)
337  * @param prop_name	name of property to find
338  * @param addr		returns pci address in the form of fdt_pci_addr
339  * @return 0 if ok, -ENOENT if the property did not exist, -EINVAL if the
340  *		format of the property was invalid, -ENXIO if the requested
341  *		address type was not found
342  */
343 int fdtdec_get_pci_addr(const void *blob, int node, enum fdt_pci_space type,
344 		const char *prop_name, struct fdt_pci_addr *addr);
345 
346 /**
347  * Look at the compatible property of a device node that represents a PCI
348  * device and extract pci vendor id and device id from it.
349  *
350  * @param blob		FDT blob
351  * @param node		node to examine
352  * @param vendor	vendor id of the pci device
353  * @param device	device id of the pci device
354  * @return 0 if ok, negative on error
355  */
356 int fdtdec_get_pci_vendev(const void *blob, int node,
357 		u16 *vendor, u16 *device);
358 
359 /**
360  * Look at the pci address of a device node that represents a PCI device
361  * and parse the bus, device and function number from it. For some cases
362  * like the bus number encoded in reg property is not correct after pci
363  * enumeration, this function looks through the node's compatible strings
364  * to get these numbers extracted instead.
365  *
366  * @param blob		FDT blob
367  * @param node		node to examine
368  * @param addr		pci address in the form of fdt_pci_addr
369  * @param bdf		returns bus, device, function triplet
370  * @return 0 if ok, negative on error
371  */
372 int fdtdec_get_pci_bdf(const void *blob, int node,
373 		struct fdt_pci_addr *addr, pci_dev_t *bdf);
374 
375 /**
376  * Look at the pci address of a device node that represents a PCI device
377  * and return base address of the pci device's registers.
378  *
379  * @param blob		FDT blob
380  * @param node		node to examine
381  * @param addr		pci address in the form of fdt_pci_addr
382  * @param bar		returns base address of the pci device's registers
383  * @return 0 if ok, negative on error
384  */
385 int fdtdec_get_pci_bar32(const void *blob, int node,
386 		struct fdt_pci_addr *addr, u32 *bar);
387 
388 /**
389  * Look up a 32-bit integer property in a node and return it. The property
390  * must have at least 4 bytes of data. The value of the first cell is
391  * returned.
392  *
393  * @param blob	FDT blob
394  * @param node	node to examine
395  * @param prop_name	name of property to find
396  * @param default_val	default value to return if the property is not found
397  * @return integer value, if found, or default_val if not
398  */
399 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
400 		s32 default_val);
401 
402 /**
403  * Get a variable-sized number from a property
404  *
405  * This reads a number from one or more cells.
406  *
407  * @param ptr	Pointer to property
408  * @param cells	Number of cells containing the number
409  * @return the value in the cells
410  */
411 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells);
412 
413 /**
414  * Look up a 64-bit integer property in a node and return it. The property
415  * must have at least 8 bytes of data (2 cells). The first two cells are
416  * concatenated to form a 8 bytes value, where the first cell is top half and
417  * the second cell is bottom half.
418  *
419  * @param blob	FDT blob
420  * @param node	node to examine
421  * @param prop_name	name of property to find
422  * @param default_val	default value to return if the property is not found
423  * @return integer value, if found, or default_val if not
424  */
425 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
426 		uint64_t default_val);
427 
428 /**
429  * Checks whether a node is enabled.
430  * This looks for a 'status' property. If this exists, then returns 1 if
431  * the status is 'ok' and 0 otherwise. If there is no status property,
432  * it returns 1 on the assumption that anything mentioned should be enabled
433  * by default.
434  *
435  * @param blob	FDT blob
436  * @param node	node to examine
437  * @return integer value 0 (not enabled) or 1 (enabled)
438  */
439 int fdtdec_get_is_enabled(const void *blob, int node);
440 
441 /**
442  * Make sure we have a valid fdt available to control U-Boot.
443  *
444  * If not, a message is printed to the console if the console is ready.
445  *
446  * @return 0 if all ok, -1 if not
447  */
448 int fdtdec_prepare_fdt(void);
449 
450 /**
451  * Checks that we have a valid fdt available to control U-Boot.
452 
453  * However, if not then for the moment nothing is done, since this function
454  * is called too early to panic().
455  *
456  * @returns 0
457  */
458 int fdtdec_check_fdt(void);
459 
460 /**
461  * Find the nodes for a peripheral and return a list of them in the correct
462  * order. This is used to enumerate all the peripherals of a certain type.
463  *
464  * To use this, optionally set up a /aliases node with alias properties for
465  * a peripheral. For example, for usb you could have:
466  *
467  * aliases {
468  *		usb0 = "/ehci@c5008000";
469  *		usb1 = "/ehci@c5000000";
470  * };
471  *
472  * Pass "usb" as the name to this function and will return a list of two
473  * nodes offsets: /ehci@c5008000 and ehci@c5000000.
474  *
475  * All nodes returned will match the compatible ID, as it is assumed that
476  * all peripherals use the same driver.
477  *
478  * If no alias node is found, then the node list will be returned in the
479  * order found in the fdt. If the aliases mention a node which doesn't
480  * exist, then this will be ignored. If nodes are found with no aliases,
481  * they will be added in any order.
482  *
483  * If there is a gap in the aliases, then this function return a 0 node at
484  * that position. The return value will also count these gaps.
485  *
486  * This function checks node properties and will not return nodes which are
487  * marked disabled (status = "disabled").
488  *
489  * @param blob		FDT blob to use
490  * @param name		Root name of alias to search for
491  * @param id		Compatible ID to look for
492  * @param node_list	Place to put list of found nodes
493  * @param maxcount	Maximum number of nodes to find
494  * @return number of nodes found on success, FTD_ERR_... on error
495  */
496 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
497 			enum fdt_compat_id id, int *node_list, int maxcount);
498 
499 /*
500  * This function is similar to fdtdec_find_aliases_for_id() except that it
501  * adds to the node_list that is passed in. Any 0 elements are considered
502  * available for allocation - others are considered already used and are
503  * skipped.
504  *
505  * You can use this by calling fdtdec_find_aliases_for_id() with an
506  * uninitialised array, then setting the elements that are returned to -1,
507  * say, then calling this function, perhaps with a different compat id.
508  * Any elements you get back that are >0 are new nodes added by the call
509  * to this function.
510  *
511  * Note that if you have some nodes with aliases and some without, you are
512  * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
513  * one compat_id may fill in positions for which you have aliases defined
514  * for another compat_id. When you later call *this* function with the second
515  * compat_id, the alias positions may already be used. A debug warning may
516  * be generated in this case, but it is safest to define aliases for all
517  * nodes when you care about the ordering.
518  */
519 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
520 			enum fdt_compat_id id, int *node_list, int maxcount);
521 
522 /**
523  * Get the alias sequence number of a node
524  *
525  * This works out whether a node is pointed to by an alias, and if so, the
526  * sequence number of that alias. Aliases are of the form <base><num> where
527  * <num> is the sequence number. For example spi2 would be sequence number
528  * 2.
529  *
530  * @param blob		Device tree blob (if NULL, then error is returned)
531  * @param base		Base name for alias (before the underscore)
532  * @param node		Node to look up
533  * @param seqp		This is set to the sequence number if one is found,
534  *			but otherwise the value is left alone
535  * @return 0 if a sequence was found, -ve if not
536  */
537 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
538 			 int *seqp);
539 
540 /**
541  * Get the offset of the given chosen node
542  *
543  * This looks up a property in /chosen containing the path to another node,
544  * then finds the offset of that node.
545  *
546  * @param blob		Device tree blob (if NULL, then error is returned)
547  * @param name		Property name, e.g. "stdout-path"
548  * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
549  */
550 int fdtdec_get_chosen_node(const void *blob, const char *name);
551 
552 /*
553  * Get the name for a compatible ID
554  *
555  * @param id		Compatible ID to look for
556  * @return compatible string for that id
557  */
558 const char *fdtdec_get_compatible(enum fdt_compat_id id);
559 
560 /* Look up a phandle and follow it to its node. Then return the offset
561  * of that node.
562  *
563  * @param blob		FDT blob
564  * @param node		node to examine
565  * @param prop_name	name of property to find
566  * @return node offset if found, -ve error code on error
567  */
568 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
569 
570 /**
571  * Look up a property in a node and return its contents in an integer
572  * array of given length. The property must have at least enough data for
573  * the array (4*count bytes). It may have more, but this will be ignored.
574  *
575  * @param blob		FDT blob
576  * @param node		node to examine
577  * @param prop_name	name of property to find
578  * @param array		array to fill with data
579  * @param count		number of array elements
580  * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
581  *		or -FDT_ERR_BADLAYOUT if not enough data
582  */
583 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
584 		u32 *array, int count);
585 
586 /**
587  * Look up a property in a node and return its contents in an integer
588  * array of given length. The property must exist but may have less data that
589  * expected (4*count bytes). It may have more, but this will be ignored.
590  *
591  * @param blob		FDT blob
592  * @param node		node to examine
593  * @param prop_name	name of property to find
594  * @param array		array to fill with data
595  * @param count		number of array elements
596  * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
597  *		property is not found
598  */
599 int fdtdec_get_int_array_count(const void *blob, int node,
600 			       const char *prop_name, u32 *array, int count);
601 
602 /**
603  * Look up a property in a node and return a pointer to its contents as a
604  * unsigned int array of given length. The property must have at least enough
605  * data for the array ('count' cells). It may have more, but this will be
606  * ignored. The data is not copied.
607  *
608  * Note that you must access elements of the array with fdt32_to_cpu(),
609  * since the elements will be big endian even on a little endian machine.
610  *
611  * @param blob		FDT blob
612  * @param node		node to examine
613  * @param prop_name	name of property to find
614  * @param count		number of array elements
615  * @return pointer to array if found, or NULL if the property is not
616  *		found or there is not enough data
617  */
618 const u32 *fdtdec_locate_array(const void *blob, int node,
619 			       const char *prop_name, int count);
620 
621 /**
622  * Look up a boolean property in a node and return it.
623  *
624  * A boolean properly is true if present in the device tree and false if not
625  * present, regardless of its value.
626  *
627  * @param blob	FDT blob
628  * @param node	node to examine
629  * @param prop_name	name of property to find
630  * @return 1 if the properly is present; 0 if it isn't present
631  */
632 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
633 
634 /**
635  * Look in the FDT for a config item with the given name and return its value
636  * as a 32-bit integer. The property must have at least 4 bytes of data. The
637  * value of the first cell is returned.
638  *
639  * @param blob		FDT blob to use
640  * @param prop_name	Node property name
641  * @param default_val	default value to return if the property is not found
642  * @return integer value, if found, or default_val if not
643  */
644 int fdtdec_get_config_int(const void *blob, const char *prop_name,
645 		int default_val);
646 
647 /**
648  * Look in the FDT for a config item with the given name
649  * and return whether it exists.
650  *
651  * @param blob		FDT blob
652  * @param prop_name	property name to look up
653  * @return 1, if it exists, or 0 if not
654  */
655 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
656 
657 /**
658  * Look in the FDT for a config item with the given name and return its value
659  * as a string.
660  *
661  * @param blob          FDT blob
662  * @param prop_name     property name to look up
663  * @returns property string, NULL on error.
664  */
665 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
666 
667 /*
668  * Look up a property in a node and return its contents in a byte
669  * array of given length. The property must have at least enough data for
670  * the array (count bytes). It may have more, but this will be ignored.
671  *
672  * @param blob		FDT blob
673  * @param node		node to examine
674  * @param prop_name	name of property to find
675  * @param array		array to fill with data
676  * @param count		number of array elements
677  * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
678  *		or -FDT_ERR_BADLAYOUT if not enough data
679  */
680 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
681 		u8 *array, int count);
682 
683 /**
684  * Look up a property in a node and return a pointer to its contents as a
685  * byte array of given length. The property must have at least enough data
686  * for the array (count bytes). It may have more, but this will be ignored.
687  * The data is not copied.
688  *
689  * @param blob		FDT blob
690  * @param node		node to examine
691  * @param prop_name	name of property to find
692  * @param count		number of array elements
693  * @return pointer to byte array if found, or NULL if the property is not
694  *		found or there is not enough data
695  */
696 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
697 			     const char *prop_name, int count);
698 
699 /**
700  * Look up a property in a node which contains a memory region address and
701  * size. Then return a pointer to this address.
702  *
703  * The property must hold one address with a length. This is only tested on
704  * 32-bit machines.
705  *
706  * @param blob		FDT blob
707  * @param node		node to examine
708  * @param prop_name	name of property to find
709  * @param basep		Returns base address of region
710  * @param size		Returns size of region
711  * @return 0 if ok, -1 on error (property not found)
712  */
713 int fdtdec_decode_region(const void *blob, int node, const char *prop_name,
714 			 fdt_addr_t *basep, fdt_size_t *sizep);
715 
716 enum fmap_compress_t {
717 	FMAP_COMPRESS_NONE,
718 	FMAP_COMPRESS_LZO,
719 };
720 
721 enum fmap_hash_t {
722 	FMAP_HASH_NONE,
723 	FMAP_HASH_SHA1,
724 	FMAP_HASH_SHA256,
725 };
726 
727 /* A flash map entry, containing an offset and length */
728 struct fmap_entry {
729 	uint32_t offset;
730 	uint32_t length;
731 	uint32_t used;			/* Number of bytes used in region */
732 	enum fmap_compress_t compress_algo;	/* Compression type */
733 	enum fmap_hash_t hash_algo;		/* Hash algorithm */
734 	const uint8_t *hash;			/* Hash value */
735 	int hash_size;				/* Hash size */
736 };
737 
738 /**
739  * Read a flash entry from the fdt
740  *
741  * @param blob		FDT blob
742  * @param node		Offset of node to read
743  * @param name		Name of node being read
744  * @param entry		Place to put offset and size of this node
745  * @return 0 if ok, -ve on error
746  */
747 int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
748 			   struct fmap_entry *entry);
749 
750 /**
751  * Obtain an indexed resource from a device property.
752  *
753  * @param fdt		FDT blob
754  * @param node		node to examine
755  * @param property	name of the property to parse
756  * @param index		index of the resource to retrieve
757  * @param res		returns the resource
758  * @return 0 if ok, negative on error
759  */
760 int fdt_get_resource(const void *fdt, int node, const char *property,
761 		     unsigned int index, struct fdt_resource *res);
762 
763 /**
764  * Obtain a named resource from a device property.
765  *
766  * Look up the index of the name in a list of strings and return the resource
767  * at that index.
768  *
769  * @param fdt		FDT blob
770  * @param node		node to examine
771  * @param property	name of the property to parse
772  * @param prop_names	name of the property containing the list of names
773  * @param name		the name of the entry to look up
774  * @param res		returns the resource
775  */
776 int fdt_get_named_resource(const void *fdt, int node, const char *property,
777 			   const char *prop_names, const char *name,
778 			   struct fdt_resource *res);
779 
780 /**
781  * Decode a named region within a memory bank of a given type.
782  *
783  * This function handles selection of a memory region. The region is
784  * specified as an offset/size within a particular type of memory.
785  *
786  * The properties used are:
787  *
788  *	<mem_type>-memory<suffix> for the name of the memory bank
789  *	<mem_type>-offset<suffix> for the offset in that bank
790  *
791  * The property value must have an offset and a size. The function checks
792  * that the region is entirely within the memory bank.5
793  *
794  * @param blob		FDT blob
795  * @param node		Node containing the properties (-1 for /config)
796  * @param mem_type	Type of memory to use, which is a name, such as
797  *			"u-boot" or "kernel".
798  * @param suffix	String to append to the memory/offset
799  *			property names
800  * @param basep		Returns base of region
801  * @param sizep		Returns size of region
802  * @return 0 if OK, -ive on error
803  */
804 int fdtdec_decode_memory_region(const void *blob, int node,
805 				const char *mem_type, const char *suffix,
806 				fdt_addr_t *basep, fdt_size_t *sizep);
807 
808 /* Display timings from linux include/video/display_timing.h */
809 enum display_flags {
810 	DISPLAY_FLAGS_HSYNC_LOW		= 1 << 0,
811 	DISPLAY_FLAGS_HSYNC_HIGH	= 1 << 1,
812 	DISPLAY_FLAGS_VSYNC_LOW		= 1 << 2,
813 	DISPLAY_FLAGS_VSYNC_HIGH	= 1 << 3,
814 
815 	/* data enable flag */
816 	DISPLAY_FLAGS_DE_LOW		= 1 << 4,
817 	DISPLAY_FLAGS_DE_HIGH		= 1 << 5,
818 	/* drive data on pos. edge */
819 	DISPLAY_FLAGS_PIXDATA_POSEDGE	= 1 << 6,
820 	/* drive data on neg. edge */
821 	DISPLAY_FLAGS_PIXDATA_NEGEDGE	= 1 << 7,
822 	DISPLAY_FLAGS_INTERLACED	= 1 << 8,
823 	DISPLAY_FLAGS_DOUBLESCAN	= 1 << 9,
824 	DISPLAY_FLAGS_DOUBLECLK		= 1 << 10,
825 };
826 
827 /*
828  * A single signal can be specified via a range of minimal and maximal values
829  * with a typical value, that lies somewhere inbetween.
830  */
831 struct timing_entry {
832 	u32 min;
833 	u32 typ;
834 	u32 max;
835 };
836 
837 /*
838  * Single "mode" entry. This describes one set of signal timings a display can
839  * have in one setting. This struct can later be converted to struct videomode
840  * (see include/video/videomode.h). As each timing_entry can be defined as a
841  * range, one struct display_timing may become multiple struct videomodes.
842  *
843  * Example: hsync active high, vsync active low
844  *
845  *				    Active Video
846  * Video  ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
847  *	  |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
848  *	  |	     |	 porch  |		     |	 porch	 |
849  *
850  * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
851  *
852  * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
853  */
854 struct display_timing {
855 	struct timing_entry pixelclock;
856 
857 	struct timing_entry hactive;		/* hor. active video */
858 	struct timing_entry hfront_porch;	/* hor. front porch */
859 	struct timing_entry hback_porch;	/* hor. back porch */
860 	struct timing_entry hsync_len;		/* hor. sync len */
861 
862 	struct timing_entry vactive;		/* ver. active video */
863 	struct timing_entry vfront_porch;	/* ver. front porch */
864 	struct timing_entry vback_porch;	/* ver. back porch */
865 	struct timing_entry vsync_len;		/* ver. sync len */
866 
867 	enum display_flags flags;		/* display flags */
868 };
869 
870 /**
871  * fdtdec_decode_display_timing() - decode display timings
872  *
873  * Decode display timings from the supplied 'display-timings' node.
874  * See doc/device-tree-bindings/video/display-timing.txt for binding
875  * information.
876  *
877  * @param blob		FDT blob
878  * @param node		'display-timing' node containing the timing subnodes
879  * @param index		Index number to read (0=first timing subnode)
880  * @param config	Place to put timings
881  * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
882  */
883 int fdtdec_decode_display_timing(const void *blob, int node, int index,
884 				 struct display_timing *config);
885 /**
886  * Set up the device tree ready for use
887  */
888 int fdtdec_setup(void);
889 
890 #endif
891