blob: 934438cc6ee73293bef5073eb911846d764f72a5 [file] [log] [blame]
Simon Glassb5220bc2011-10-24 19:15:32 +00001/*
2 * Copyright (c) 2011 The Chromium OS Authors.
3 * See file CREDITS for list of people who contributed to this
4 * project.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation; either version 2 of
9 * the License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
19 * MA 02111-1307 USA
20 */
21
Simon Glass5bfa78d2012-07-12 05:25:02 +000022#ifndef __fdtdec_h
23#define __fdtdec_h
Simon Glassb5220bc2011-10-24 19:15:32 +000024
25/*
26 * This file contains convenience functions for decoding useful and
27 * enlightening information from FDTs. It is intended to be used by device
28 * drivers and board-specific code within U-Boot. It aims to reduce the
29 * amount of FDT munging required within U-Boot itself, so that driver code
30 * changes to support FDT are minimized.
31 */
32
33#include <libfdt.h>
34
35/*
36 * A typedef for a physical address. Note that fdt data is always big
37 * endian even on a litle endian machine.
38 */
39#ifdef CONFIG_PHYS_64BIT
40typedef u64 fdt_addr_t;
41#define FDT_ADDR_T_NONE (-1ULL)
42#define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
Simon Glassf20c4612012-10-25 16:31:00 +000043#define fdt_size_to_cpu(reg) be64_to_cpu(reg)
Simon Glassb5220bc2011-10-24 19:15:32 +000044#else
45typedef u32 fdt_addr_t;
46#define FDT_ADDR_T_NONE (-1U)
47#define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
Simon Glassf20c4612012-10-25 16:31:00 +000048#define fdt_size_to_cpu(reg) be32_to_cpu(reg)
Simon Glassb5220bc2011-10-24 19:15:32 +000049#endif
50
51/* Information obtained about memory from the FDT */
52struct fdt_memory {
53 fdt_addr_t start;
54 fdt_addr_t end;
55};
56
57/**
58 * Compat types that we know about and for which we might have drivers.
59 * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
60 * within drivers.
61 */
62enum fdt_compat_id {
63 COMPAT_UNKNOWN,
Allen Martin00a27492012-08-31 08:30:00 +000064 COMPAT_NVIDIA_TEGRA20_USB, /* Tegra20 USB port */
65 COMPAT_NVIDIA_TEGRA20_I2C, /* Tegra20 i2c */
66 COMPAT_NVIDIA_TEGRA20_DVC, /* Tegra20 dvc (really just i2c) */
67 COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */
68 COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
69 COMPAT_NVIDIA_TEGRA20_KBC, /* Tegra20 Keyboard */
Jim Lin312693c2012-07-29 20:53:29 +000070 COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */
Simon Glasse1ae0d12012-10-17 13:24:49 +000071 COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */
Wei Ni87540de2012-10-17 13:24:50 +000072 COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */
Hatim RVcc9fe332012-12-11 00:52:46 +000073 COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */
74 COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */
Rajeshwari Shindec34253d2012-12-26 20:03:10 +000075 COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */
Simon Glassb5220bc2011-10-24 19:15:32 +000076
77 COMPAT_COUNT,
78};
79
Simon Glassed3ee5c2012-02-27 10:52:36 +000080/* GPIOs are numbered from 0 */
81enum {
82 FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */
83
84 FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */
85};
86
87/* This is the state of a GPIO pin as defined by the fdt */
88struct fdt_gpio_state {
89 const char *name; /* name of the fdt property defining this */
90 uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */
91 u8 flags; /* FDT_GPIO_... flags */
92};
93
94/* This tells us whether a fdt_gpio_state record is valid or not */
95#define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE)
96
Simon Glassb5220bc2011-10-24 19:15:32 +000097/**
Sean Paul202ff752012-10-25 16:31:06 +000098 * Read the GPIO taking into account the polarity of the pin.
99 *
100 * @param gpio pointer to the decoded gpio
101 * @return value of the gpio if successful, < 0 if unsuccessful
102 */
103int fdtdec_get_gpio(struct fdt_gpio_state *gpio);
104
105/**
106 * Write the GPIO taking into account the polarity of the pin.
107 *
108 * @param gpio pointer to the decoded gpio
109 * @return 0 if successful
110 */
111int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val);
112
113/**
Simon Glassb5220bc2011-10-24 19:15:32 +0000114 * Find the next numbered alias for a peripheral. This is used to enumerate
115 * all the peripherals of a certain type.
116 *
117 * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
118 * this function will return a pointer to the node the alias points to, and
119 * then update *upto to 1. Next time you call this function, the next node
120 * will be returned.
121 *
122 * All nodes returned will match the compatible ID, as it is assumed that
123 * all peripherals use the same driver.
124 *
125 * @param blob FDT blob to use
126 * @param name Root name of alias to search for
127 * @param id Compatible ID to look for
128 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
129 */
130int fdtdec_next_alias(const void *blob, const char *name,
131 enum fdt_compat_id id, int *upto);
132
133/**
Gerald Van Baren7cde3972012-11-12 23:13:54 -0500134 * Find the compatible ID for a given node.
135 *
136 * Generally each node has at least one compatible string attached to it.
137 * This function looks through our list of known compatible strings and
138 * returns the corresponding ID which matches the compatible string.
139 *
140 * @param blob FDT blob to use
141 * @param node Node containing compatible string to find
142 * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
143 */
144enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
145
146/**
Simon Glassf88fe2d2012-02-27 10:52:34 +0000147 * Find the next compatible node for a peripheral.
148 *
149 * Do the first call with node = 0. This function will return a pointer to
150 * the next compatible node. Next time you call this function, pass the
151 * value returned, and the next node will be provided.
152 *
153 * @param blob FDT blob to use
154 * @param node Start node for search
155 * @param id Compatible ID to look for (enum fdt_compat_id)
156 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
157 */
158int fdtdec_next_compatible(const void *blob, int node,
159 enum fdt_compat_id id);
160
161/**
Simon Glass3ddecfc2012-04-02 13:18:42 +0000162 * Find the next compatible subnode for a peripheral.
163 *
164 * Do the first call with node set to the parent and depth = 0. This
165 * function will return the offset of the next compatible node. Next time
166 * you call this function, pass the node value returned last time, with
167 * depth unchanged, and the next node will be provided.
168 *
169 * @param blob FDT blob to use
170 * @param node Start node for search
171 * @param id Compatible ID to look for (enum fdt_compat_id)
172 * @param depthp Current depth (set to 0 before first call)
173 * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
174 */
175int fdtdec_next_compatible_subnode(const void *blob, int node,
176 enum fdt_compat_id id, int *depthp);
177
178/**
Simon Glassb5220bc2011-10-24 19:15:32 +0000179 * Look up an address property in a node and return it as an address.
180 * The property must hold either one address with no trailing data or
181 * one address with a length. This is only tested on 32-bit machines.
182 *
183 * @param blob FDT blob
184 * @param node node to examine
185 * @param prop_name name of property to find
186 * @return address, if found, or FDT_ADDR_T_NONE if not
187 */
188fdt_addr_t fdtdec_get_addr(const void *blob, int node,
189 const char *prop_name);
190
191/**
192 * Look up a 32-bit integer property in a node and return it. The property
193 * must have at least 4 bytes of data. The value of the first cell is
194 * returned.
195 *
196 * @param blob FDT blob
197 * @param node node to examine
198 * @param prop_name name of property to find
199 * @param default_val default value to return if the property is not found
200 * @return integer value, if found, or default_val if not
201 */
202s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
203 s32 default_val);
204
205/**
Che-Liang Chiouaadef0a2012-10-25 16:31:05 +0000206 * Look up a 64-bit integer property in a node and return it. The property
207 * must have at least 8 bytes of data (2 cells). The first two cells are
208 * concatenated to form a 8 bytes value, where the first cell is top half and
209 * the second cell is bottom half.
210 *
211 * @param blob FDT blob
212 * @param node node to examine
213 * @param prop_name name of property to find
214 * @param default_val default value to return if the property is not found
215 * @return integer value, if found, or default_val if not
216 */
217uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
218 uint64_t default_val);
219
220/**
Simon Glassb5220bc2011-10-24 19:15:32 +0000221 * Checks whether a node is enabled.
222 * This looks for a 'status' property. If this exists, then returns 1 if
223 * the status is 'ok' and 0 otherwise. If there is no status property,
Simon Glassf88fe2d2012-02-27 10:52:34 +0000224 * it returns 1 on the assumption that anything mentioned should be enabled
225 * by default.
Simon Glassb5220bc2011-10-24 19:15:32 +0000226 *
227 * @param blob FDT blob
228 * @param node node to examine
Simon Glassf88fe2d2012-02-27 10:52:34 +0000229 * @return integer value 0 (not enabled) or 1 (enabled)
Simon Glassb5220bc2011-10-24 19:15:32 +0000230 */
Simon Glassf88fe2d2012-02-27 10:52:34 +0000231int fdtdec_get_is_enabled(const void *blob, int node);
Simon Glassb5220bc2011-10-24 19:15:32 +0000232
233/**
Simon Glass9a263e52012-03-28 10:08:24 +0000234 * Make sure we have a valid fdt available to control U-Boot.
235 *
236 * If not, a message is printed to the console if the console is ready.
237 *
238 * @return 0 if all ok, -1 if not
239 */
240int fdtdec_prepare_fdt(void);
241
242/**
243 * Checks that we have a valid fdt available to control U-Boot.
244
245 * However, if not then for the moment nothing is done, since this function
246 * is called too early to panic().
247 *
248 * @returns 0
Simon Glassb5220bc2011-10-24 19:15:32 +0000249 */
250int fdtdec_check_fdt(void);
Simon Glassa53f4a22012-01-17 08:20:50 +0000251
252/**
253 * Find the nodes for a peripheral and return a list of them in the correct
254 * order. This is used to enumerate all the peripherals of a certain type.
255 *
256 * To use this, optionally set up a /aliases node with alias properties for
257 * a peripheral. For example, for usb you could have:
258 *
259 * aliases {
260 * usb0 = "/ehci@c5008000";
261 * usb1 = "/ehci@c5000000";
262 * };
263 *
264 * Pass "usb" as the name to this function and will return a list of two
265 * nodes offsets: /ehci@c5008000 and ehci@c5000000.
266 *
267 * All nodes returned will match the compatible ID, as it is assumed that
268 * all peripherals use the same driver.
269 *
270 * If no alias node is found, then the node list will be returned in the
271 * order found in the fdt. If the aliases mention a node which doesn't
272 * exist, then this will be ignored. If nodes are found with no aliases,
273 * they will be added in any order.
274 *
275 * If there is a gap in the aliases, then this function return a 0 node at
276 * that position. The return value will also count these gaps.
277 *
278 * This function checks node properties and will not return nodes which are
279 * marked disabled (status = "disabled").
280 *
281 * @param blob FDT blob to use
282 * @param name Root name of alias to search for
283 * @param id Compatible ID to look for
284 * @param node_list Place to put list of found nodes
285 * @param maxcount Maximum number of nodes to find
286 * @return number of nodes found on success, FTD_ERR_... on error
287 */
288int fdtdec_find_aliases_for_id(const void *blob, const char *name,
289 enum fdt_compat_id id, int *node_list, int maxcount);
290
291/*
Simon Glassc6782272012-02-03 15:13:53 +0000292 * This function is similar to fdtdec_find_aliases_for_id() except that it
293 * adds to the node_list that is passed in. Any 0 elements are considered
294 * available for allocation - others are considered already used and are
295 * skipped.
296 *
297 * You can use this by calling fdtdec_find_aliases_for_id() with an
298 * uninitialised array, then setting the elements that are returned to -1,
299 * say, then calling this function, perhaps with a different compat id.
300 * Any elements you get back that are >0 are new nodes added by the call
301 * to this function.
302 *
303 * Note that if you have some nodes with aliases and some without, you are
304 * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
305 * one compat_id may fill in positions for which you have aliases defined
306 * for another compat_id. When you later call *this* function with the second
307 * compat_id, the alias positions may already be used. A debug warning may
308 * be generated in this case, but it is safest to define aliases for all
309 * nodes when you care about the ordering.
310 */
311int fdtdec_add_aliases_for_id(const void *blob, const char *name,
312 enum fdt_compat_id id, int *node_list, int maxcount);
313
314/*
Simon Glassa53f4a22012-01-17 08:20:50 +0000315 * Get the name for a compatible ID
316 *
317 * @param id Compatible ID to look for
318 * @return compatible string for that id
319 */
320const char *fdtdec_get_compatible(enum fdt_compat_id id);
Simon Glassd17da652012-02-27 10:52:35 +0000321
322/* Look up a phandle and follow it to its node. Then return the offset
323 * of that node.
324 *
325 * @param blob FDT blob
326 * @param node node to examine
327 * @param prop_name name of property to find
328 * @return node offset if found, -ve error code on error
329 */
330int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
331
332/**
333 * Look up a property in a node and return its contents in an integer
334 * array of given length. The property must have at least enough data for
335 * the array (4*count bytes). It may have more, but this will be ignored.
336 *
337 * @param blob FDT blob
338 * @param node node to examine
339 * @param prop_name name of property to find
340 * @param array array to fill with data
341 * @param count number of array elements
342 * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
343 * or -FDT_ERR_BADLAYOUT if not enough data
344 */
345int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
346 u32 *array, int count);
347
348/**
Simon Glass96875e72012-04-02 13:18:41 +0000349 * Look up a property in a node and return a pointer to its contents as a
350 * unsigned int array of given length. The property must have at least enough
351 * data for the array ('count' cells). It may have more, but this will be
352 * ignored. The data is not copied.
353 *
354 * Note that you must access elements of the array with fdt32_to_cpu(),
355 * since the elements will be big endian even on a little endian machine.
356 *
357 * @param blob FDT blob
358 * @param node node to examine
359 * @param prop_name name of property to find
360 * @param count number of array elements
361 * @return pointer to array if found, or NULL if the property is not
362 * found or there is not enough data
363 */
364const u32 *fdtdec_locate_array(const void *blob, int node,
365 const char *prop_name, int count);
366
367/**
Simon Glassd17da652012-02-27 10:52:35 +0000368 * Look up a boolean property in a node and return it.
369 *
370 * A boolean properly is true if present in the device tree and false if not
371 * present, regardless of its value.
372 *
373 * @param blob FDT blob
374 * @param node node to examine
375 * @param prop_name name of property to find
376 * @return 1 if the properly is present; 0 if it isn't present
377 */
378int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
Simon Glassed3ee5c2012-02-27 10:52:36 +0000379
380/**
381 * Decode a single GPIOs from an FDT.
382 *
383 * If the property is not found, then the GPIO structure will still be
384 * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to
385 * provide optional GPIOs.
386 *
387 * @param blob FDT blob to use
388 * @param node Node to look at
389 * @param prop_name Node property name
390 * @param gpio gpio elements to fill from FDT
391 * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing.
392 */
393int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name,
394 struct fdt_gpio_state *gpio);
395
396/**
Abhilash Kesavan5921f6a2012-10-25 16:31:01 +0000397 * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no
398 * terminating item.
399 *
400 * @param blob FDT blob to use
401 * @param node Node to look at
402 * @param prop_name Node property name
403 * @param gpio Array of gpio elements to fill from FDT. This will be
404 * untouched if either 0 or an error is returned
405 * @param max_count Maximum number of elements allowed
406 * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would
407 * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing.
408 */
409int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name,
410 struct fdt_gpio_state *gpio, int max_count);
411
412/**
Simon Glassed3ee5c2012-02-27 10:52:36 +0000413 * Set up a GPIO pin according to the provided gpio information. At present this
414 * just requests the GPIO.
415 *
416 * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to
417 * deal with optional GPIOs.
418 *
419 * @param gpio GPIO info to use for set up
420 * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error
421 */
422int fdtdec_setup_gpio(struct fdt_gpio_state *gpio);
Anton Staffbed4d892012-04-17 09:01:28 +0000423
Abhilash Kesavan09258f12012-10-25 16:30:58 +0000424/**
425 * Look in the FDT for a config item with the given name and return its value
426 * as a 32-bit integer. The property must have at least 4 bytes of data. The
427 * value of the first cell is returned.
428 *
429 * @param blob FDT blob to use
430 * @param prop_name Node property name
431 * @param default_val default value to return if the property is not found
432 * @return integer value, if found, or default_val if not
433 */
434int fdtdec_get_config_int(const void *blob, const char *prop_name,
435 int default_val);
436
Simon Glass332ab0d2012-10-25 16:30:59 +0000437/**
Gabe Black79289c02012-10-25 16:31:04 +0000438 * Look in the FDT for a config item with the given name
439 * and return whether it exists.
440 *
441 * @param blob FDT blob
442 * @param prop_name property name to look up
443 * @return 1, if it exists, or 0 if not
444 */
445int fdtdec_get_config_bool(const void *blob, const char *prop_name);
446
447/**
Simon Glass332ab0d2012-10-25 16:30:59 +0000448 * Look in the FDT for a config item with the given name and return its value
449 * as a string.
450 *
451 * @param blob FDT blob
452 * @param prop_name property name to look up
453 * @returns property string, NULL on error.
454 */
455char *fdtdec_get_config_string(const void *blob, const char *prop_name);
456
Anton Staffbed4d892012-04-17 09:01:28 +0000457/*
458 * Look up a property in a node and return its contents in a byte
459 * array of given length. The property must have at least enough data for
460 * the array (count bytes). It may have more, but this will be ignored.
461 *
462 * @param blob FDT blob
463 * @param node node to examine
464 * @param prop_name name of property to find
465 * @param array array to fill with data
466 * @param count number of array elements
467 * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
468 * or -FDT_ERR_BADLAYOUT if not enough data
469 */
470int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
471 u8 *array, int count);
472
473/**
474 * Look up a property in a node and return a pointer to its contents as a
475 * byte array of given length. The property must have at least enough data
476 * for the array (count bytes). It may have more, but this will be ignored.
477 * The data is not copied.
478 *
479 * @param blob FDT blob
480 * @param node node to examine
481 * @param prop_name name of property to find
482 * @param count number of array elements
483 * @return pointer to byte array if found, or NULL if the property is not
484 * found or there is not enough data
485 */
486const u8 *fdtdec_locate_byte_array(const void *blob, int node,
487 const char *prop_name, int count);
Simon Glassf20c4612012-10-25 16:31:00 +0000488
489/**
490 * Look up a property in a node which contains a memory region address and
491 * size. Then return a pointer to this address.
492 *
493 * The property must hold one address with a length. This is only tested on
494 * 32-bit machines.
495 *
496 * @param blob FDT blob
497 * @param node node to examine
498 * @param prop_name name of property to find
499 * @param ptrp returns pointer to region, or NULL if no address
500 * @param size returns size of region
501 * @return 0 if ok, -1 on error (propery not found)
502 */
503int fdtdec_decode_region(const void *blob, int node,
504 const char *prop_name, void **ptrp, size_t *size);
Simon Glass5bfa78d2012-07-12 05:25:02 +0000505#endif