xref: /openbmc/u-boot/include/dm/read.h (revision 85231c08)
1 /*
2  * Function to read values from the device tree node attached to a udevice.
3  *
4  * Copyright (c) 2017 Google, Inc
5  * Written by Simon Glass <sjg@chromium.org>
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #ifndef _DM_READ_H
11 #define _DM_READ_H
12 
13 #include <dm/fdtaddr.h>
14 #include <dm/ofnode.h>
15 #include <dm/uclass.h>
16 
17 struct resource;
18 
19 #if CONFIG_IS_ENABLED(OF_LIVE)
20 static inline const struct device_node *dev_np(struct udevice *dev)
21 {
22 	return ofnode_to_np(dev->node);
23 }
24 #else
25 static inline const struct device_node *dev_np(struct udevice *dev)
26 {
27 	return NULL;
28 }
29 #endif
30 
31 /**
32  * dev_ofnode() - get the DT node reference associated with a udevice
33  *
34  * @dev:	device to check
35  * @return reference of the the device's DT node
36  */
37 static inline ofnode dev_ofnode(struct udevice *dev)
38 {
39 	return dev->node;
40 }
41 
42 static inline bool dev_of_valid(struct udevice *dev)
43 {
44 	return ofnode_valid(dev_ofnode(dev));
45 }
46 
47 #ifndef CONFIG_DM_DEV_READ_INLINE
48 /**
49  * dev_read_u32() - read a 32-bit integer from a device's DT property
50  *
51  * @dev:	device to read DT property from
52  * @propname:	name of the property to read from
53  * @outp:	place to put value (if found)
54  * @return 0 if OK, -ve on error
55  */
56 int dev_read_u32(struct udevice *dev, const char *propname, u32 *outp);
57 
58 /**
59  * dev_read_u32_default() - read a 32-bit integer from a device's DT property
60  *
61  * @dev:	device to read DT property from
62  * @propname:	name of the property to read from
63  * @def:	default value to return if the property has no value
64  * @return property value, or @def if not found
65  */
66 int dev_read_u32_default(struct udevice *dev, const char *propname, int def);
67 
68 /**
69  * dev_read_string() - Read a string from a device's DT property
70  *
71  * @dev:	device to read DT property from
72  * @propname:	name of the property to read
73  * @return string from property value, or NULL if there is no such property
74  */
75 const char *dev_read_string(struct udevice *dev, const char *propname);
76 
77 /**
78  * dev_read_bool() - read a boolean value from a device's DT property
79  *
80  * @dev:	device to read DT property from
81  * @propname:	name of property to read
82  * @return true if property is present (meaning true), false if not present
83  */
84 bool dev_read_bool(struct udevice *dev, const char *propname);
85 
86 /**
87  * dev_read_subnode() - find a named subnode of a device
88  *
89  * @dev:	device whose DT node contains the subnode
90  * @subnode_name: name of subnode to find
91  * @return reference to subnode (which can be invalid if there is no such
92  * subnode)
93  */
94 ofnode dev_read_subnode(struct udevice *dev, const char *subbnode_name);
95 
96 /**
97  * dev_read_size() - read the size of a property
98  *
99  * @dev: device to check
100  * @propname: property to check
101  * @return size of property if present, or -EINVAL if not
102  */
103 int dev_read_size(struct udevice *dev, const char *propname);
104 
105 /**
106  * dev_read_addr_index() - Get the indexed reg property of a device
107  *
108  * @dev: Device to read from
109  * @index: the 'reg' property can hold a list of <addr, size> pairs
110  *	   and @index is used to select which one is required
111  *
112  * @return address or FDT_ADDR_T_NONE if not found
113  */
114 fdt_addr_t dev_read_addr_index(struct udevice *dev, int index);
115 
116 /**
117  * dev_read_addr() - Get the reg property of a device
118  *
119  * @dev: Device to read from
120  *
121  * @return address or FDT_ADDR_T_NONE if not found
122  */
123 fdt_addr_t dev_read_addr(struct udevice *dev);
124 
125 /**
126  * dev_read_addr_ptr() - Get the reg property of a device
127  *                       as a pointer
128  *
129  * @dev: Device to read from
130  *
131  * @return pointer or NULL if not found
132  */
133 void *dev_read_addr_ptr(struct udevice *dev);
134 
135 /**
136  * dev_read_addr_size() - get address and size from a device property
137  *
138  * This does no address translation. It simply reads an property that contains
139  * an address and a size value, one after the other.
140  *
141  * @dev: Device to read from
142  * @propname: property to read
143  * @sizep: place to put size value (on success)
144  * @return address value, or FDT_ADDR_T_NONE on error
145  */
146 fdt_addr_t dev_read_addr_size(struct udevice *dev, const char *propname,
147 				fdt_size_t *sizep);
148 
149 /**
150  * dev_read_name() - get the name of a device's node
151  *
152  * @node: valid node to look up
153  * @return name of node
154  */
155 const char *dev_read_name(struct udevice *dev);
156 
157 /**
158  * dev_read_stringlist_search() - find string in a string list and return index
159  *
160  * Note that it is possible for this function to succeed on property values
161  * that are not NUL-terminated. That's because the function will stop after
162  * finding the first occurrence of @string. This can for example happen with
163  * small-valued cell properties, such as #address-cells, when searching for
164  * the empty string.
165  *
166  * @dev: device to check
167  * @propname: name of the property containing the string list
168  * @string: string to look up in the string list
169  *
170  * @return:
171  *   the index of the string in the list of strings
172  *   -ENODATA if the property is not found
173  *   -EINVAL on some other error
174  */
175 int dev_read_stringlist_search(struct udevice *dev, const char *property,
176 			  const char *string);
177 
178 /**
179  * dev_read_string_index() - obtain an indexed string from a string list
180  *
181  * @dev: device to examine
182  * @propname: name of the property containing the string list
183  * @index: index of the string to return
184  * @out: return location for the string
185  *
186  * @return:
187  *   length of string, if found or -ve error value if not found
188  */
189 int dev_read_string_index(struct udevice *dev, const char *propname, int index,
190 			  const char **outp);
191 
192 /**
193  * dev_read_string_count() - find the number of strings in a string list
194  *
195  * @dev: device to examine
196  * @propname: name of the property containing the string list
197  * @return:
198  *   number of strings in the list, or -ve error value if not found
199  */
200 int dev_read_string_count(struct udevice *dev, const char *propname);
201 /**
202  * dev_read_phandle_with_args() - Find a node pointed by phandle in a list
203  *
204  * This function is useful to parse lists of phandles and their arguments.
205  * Returns 0 on success and fills out_args, on error returns appropriate
206  * errno value.
207  *
208  * Caller is responsible to call of_node_put() on the returned out_args->np
209  * pointer.
210  *
211  * Example:
212  *
213  * phandle1: node1 {
214  *	#list-cells = <2>;
215  * }
216  *
217  * phandle2: node2 {
218  *	#list-cells = <1>;
219  * }
220  *
221  * node3 {
222  *	list = <&phandle1 1 2 &phandle2 3>;
223  * }
224  *
225  * To get a device_node of the `node2' node you may call this:
226  * dev_read_phandle_with_args(dev, "list", "#list-cells", 0, 1, &args);
227  *
228  * @dev:	device whose node containing a list
229  * @list_name:	property name that contains a list
230  * @cells_name:	property name that specifies phandles' arguments count
231  * @cells_count: Cell count to use if @cells_name is NULL
232  * @index:	index of a phandle to parse out
233  * @out_args:	optional pointer to output arguments structure (will be filled)
234  * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
235  *	@list_name does not exist, -EINVAL if a phandle was not found,
236  *	@cells_name could not be found, the arguments were truncated or there
237  *	were too many arguments.
238  */
239 int dev_read_phandle_with_args(struct udevice *dev, const char *list_name,
240 				const char *cells_name, int cell_count,
241 				int index,
242 				struct ofnode_phandle_args *out_args);
243 
244 /**
245  * dev_count_phandle_with_args() - Return phandle number in a list
246  *
247  * This function is usefull to get phandle number contained in a property list.
248  * For example, this allows to allocate the right amount of memory to keep
249  * clock's reference contained into the "clocks" property.
250  *
251  *
252  * @dev:	device whose node containing a list
253  * @list_name:	property name that contains a list
254  * @cells_name:	property name that specifies phandles' arguments count
255  * @Returns number of phandle found on success, on error returns appropriate
256  * errno value.
257  */
258 
259 int dev_count_phandle_with_args(struct udevice *dev, const char *list_name,
260 				const char *cells_name);
261 
262 /**
263  * dev_read_addr_cells() - Get the number of address cells for a device's node
264  *
265  * This walks back up the tree to find the closest #address-cells property
266  * which controls the given node.
267  *
268  * @dev: device to check
269  * @return number of address cells this node uses
270  */
271 int dev_read_addr_cells(struct udevice *dev);
272 
273 /**
274  * dev_read_size_cells() - Get the number of size cells for a device's node
275  *
276  * This walks back up the tree to find the closest #size-cells property
277  * which controls the given node.
278  *
279  * @dev: device to check
280  * @return number of size cells this node uses
281  */
282 int dev_read_size_cells(struct udevice *dev);
283 
284 /**
285  * dev_read_addr_cells() - Get the address cells property in a node
286  *
287  * This function matches fdt_address_cells().
288  *
289  * @dev: device to check
290  * @return number of address cells this node uses
291  */
292 int dev_read_simple_addr_cells(struct udevice *dev);
293 
294 /**
295  * dev_read_size_cells() - Get the size cells property in a node
296  *
297  * This function matches fdt_size_cells().
298  *
299  * @dev: device to check
300  * @return number of size cells this node uses
301  */
302 int dev_read_simple_size_cells(struct udevice *dev);
303 
304 /**
305  * dev_read_phandle() - Get the phandle from a device
306  *
307  * @dev: device to check
308  * @return phandle (1 or greater), or 0 if no phandle or other error
309  */
310 int dev_read_phandle(struct udevice *dev);
311 
312 /**
313  * dev_read_prop()- - read a property from a device's node
314  *
315  * @dev: device to check
316  * @propname: property to read
317  * @lenp: place to put length on success
318  * @return pointer to property, or NULL if not found
319  */
320 const void *dev_read_prop(struct udevice *dev, const char *propname, int *lenp);
321 
322 /**
323  * dev_read_alias_seq() - Get the alias sequence number of a node
324  *
325  * This works out whether a node is pointed to by an alias, and if so, the
326  * sequence number of that alias. Aliases are of the form <base><num> where
327  * <num> is the sequence number. For example spi2 would be sequence number 2.
328  *
329  * @dev: device to look up
330  * @devnump: set to the sequence number if one is found
331  * @return 0 if a sequence was found, -ve if not
332  */
333 int dev_read_alias_seq(struct udevice *dev, int *devnump);
334 
335 /**
336  * dev_read_u32_array() - Find and read an array of 32 bit integers
337  *
338  * Search for a property in a device node and read 32-bit value(s) from
339  * it.
340  *
341  * The out_values is modified only if a valid u32 value can be decoded.
342  *
343  * @dev: device to look up
344  * @propname:	name of the property to read
345  * @out_values:	pointer to return value, modified only if return value is 0
346  * @sz:		number of array elements to read
347  * @return 0 on success, -EINVAL if the property does not exist, -ENODATA if
348  * property does not have a value, and -EOVERFLOW if the property data isn't
349  * large enough.
350  */
351 int dev_read_u32_array(struct udevice *dev, const char *propname,
352 		       u32 *out_values, size_t sz);
353 
354 /**
355  * dev_read_first_subnode() - find the first subnode of a device's node
356  *
357  * @dev: device to look up
358  * @return reference to the first subnode (which can be invalid if the device's
359  * node has no subnodes)
360  */
361 ofnode dev_read_first_subnode(struct udevice *dev);
362 
363 /**
364  * ofnode_next_subnode() - find the next sibling of a subnode
365  *
366  * @node:	valid reference to previous node (sibling)
367  * @return reference to the next subnode (which can be invalid if the node
368  * has no more siblings)
369  */
370 ofnode dev_read_next_subnode(ofnode node);
371 
372 /**
373  * dev_read_u8_array_ptr() - find an 8-bit array
374  *
375  * Look up a device's node property and return a pointer to its contents as a
376  * byte array of given length. The property must have at least enough data
377  * for the array (count bytes). It may have more, but this will be ignored.
378  * The data is not copied.
379  *
380  * @dev: device to look up
381  * @propname: name of property to find
382  * @sz: number of array elements
383  * @return pointer to byte array if found, or NULL if the property is not
384  *		found or there is not enough data
385  */
386 const uint8_t *dev_read_u8_array_ptr(struct udevice *dev, const char *propname,
387 				     size_t sz);
388 
389 /**
390  * dev_read_enabled() - check whether a node is enabled
391  *
392  * This looks for a 'status' property. If this exists, then returns 1 if
393  * the status is 'ok' and 0 otherwise. If there is no status property,
394  * it returns 1 on the assumption that anything mentioned should be enabled
395  * by default.
396  *
397  * @dev: device to examine
398  * @return integer value 0 (not enabled) or 1 (enabled)
399  */
400 int dev_read_enabled(struct udevice *dev);
401 
402 /**
403  * dev_read_resource() - obtain an indexed resource from a device.
404  *
405  * @dev: device to examine
406  * @index index of the resource to retrieve (0 = first)
407  * @res returns the resource
408  * @return 0 if ok, negative on error
409  */
410 int dev_read_resource(struct udevice *dev, uint index, struct resource *res);
411 
412 /**
413  * dev_read_resource_byname() - obtain a named resource from a device.
414  *
415  * @dev: device to examine
416  * @name: name of the resource to retrieve
417  * @res: returns the resource
418  * @return 0 if ok, negative on error
419  */
420 int dev_read_resource_byname(struct udevice *dev, const char *name,
421 			     struct resource *res);
422 
423 /**
424  * dev_translate_address() - Tranlate a device-tree address
425  *
426  * Translate an address from the device-tree into a CPU physical address.  This
427  * function walks up the tree and applies the various bus mappings along the
428  * way.
429  *
430  * @dev: device giving the context in which to translate the address
431  * @in_addr: pointer to the address to translate
432  * @return the translated address; OF_BAD_ADDR on error
433  */
434 u64 dev_translate_address(struct udevice *dev, const fdt32_t *in_addr);
435 #else /* CONFIG_DM_DEV_READ_INLINE is enabled */
436 
437 static inline int dev_read_u32(struct udevice *dev,
438 			       const char *propname, u32 *outp)
439 {
440 	return ofnode_read_u32(dev_ofnode(dev), propname, outp);
441 }
442 
443 static inline int dev_read_u32_default(struct udevice *dev,
444 				       const char *propname, int def)
445 {
446 	return ofnode_read_u32_default(dev_ofnode(dev), propname, def);
447 }
448 
449 static inline const char *dev_read_string(struct udevice *dev,
450 					  const char *propname)
451 {
452 	return ofnode_read_string(dev_ofnode(dev), propname);
453 }
454 
455 static inline bool dev_read_bool(struct udevice *dev, const char *propname)
456 {
457 	return ofnode_read_bool(dev_ofnode(dev), propname);
458 }
459 
460 static inline ofnode dev_read_subnode(struct udevice *dev,
461 				      const char *subbnode_name)
462 {
463 	return ofnode_find_subnode(dev_ofnode(dev), subbnode_name);
464 }
465 
466 static inline int dev_read_size(struct udevice *dev, const char *propname)
467 {
468 	return ofnode_read_size(dev_ofnode(dev), propname);
469 }
470 
471 static inline fdt_addr_t dev_read_addr_index(struct udevice *dev, int index)
472 {
473 	return devfdt_get_addr_index(dev, index);
474 }
475 
476 static inline fdt_addr_t dev_read_addr(struct udevice *dev)
477 {
478 	return devfdt_get_addr(dev);
479 }
480 
481 static inline void *dev_read_addr_ptr(struct udevice *dev)
482 {
483 	return devfdt_get_addr_ptr(dev);
484 }
485 
486 static inline fdt_addr_t dev_read_addr_size(struct udevice *dev,
487 					    const char *propname,
488 					    fdt_size_t *sizep)
489 {
490 	return ofnode_get_addr_size(dev_ofnode(dev), propname, sizep);
491 }
492 
493 static inline const char *dev_read_name(struct udevice *dev)
494 {
495 	return ofnode_get_name(dev_ofnode(dev));
496 }
497 
498 static inline int dev_read_stringlist_search(struct udevice *dev,
499 					     const char *propname,
500 					     const char *string)
501 {
502 	return ofnode_stringlist_search(dev_ofnode(dev), propname, string);
503 }
504 
505 static inline int dev_read_string_index(struct udevice *dev,
506 					const char *propname, int index,
507 					const char **outp)
508 {
509 	return ofnode_read_string_index(dev_ofnode(dev), propname, index, outp);
510 }
511 
512 static inline int dev_read_string_count(struct udevice *dev,
513 					const char *propname)
514 {
515 	return ofnode_read_string_count(dev_ofnode(dev), propname);
516 }
517 
518 static inline int dev_read_phandle_with_args(struct udevice *dev,
519 		const char *list_name, const char *cells_name, int cell_count,
520 		int index, struct ofnode_phandle_args *out_args)
521 {
522 	return ofnode_parse_phandle_with_args(dev_ofnode(dev), list_name,
523 					      cells_name, cell_count, index,
524 					      out_args);
525 }
526 
527 static inline int dev_count_phandle_with_args(struct udevice *dev,
528 		const char *list_name, const char *cells_name)
529 {
530 	return ofnode_count_phandle_with_args(dev_ofnode(dev), list_name,
531 					      cells_name);
532 }
533 
534 static inline int dev_read_addr_cells(struct udevice *dev)
535 {
536 	/* NOTE: this call should walk up the parent stack */
537 	return fdt_address_cells(gd->fdt_blob, dev_of_offset(dev));
538 }
539 
540 static inline int dev_read_size_cells(struct udevice *dev)
541 {
542 	/* NOTE: this call should walk up the parent stack */
543 	return fdt_size_cells(gd->fdt_blob, dev_of_offset(dev));
544 }
545 
546 static inline int dev_read_simple_addr_cells(struct udevice *dev)
547 {
548 	return fdt_address_cells(gd->fdt_blob, dev_of_offset(dev));
549 }
550 
551 static inline int dev_read_simple_size_cells(struct udevice *dev)
552 {
553 	return fdt_size_cells(gd->fdt_blob, dev_of_offset(dev));
554 }
555 
556 static inline int dev_read_phandle(struct udevice *dev)
557 {
558 	return fdt_get_phandle(gd->fdt_blob, dev_of_offset(dev));
559 }
560 
561 static inline const void *dev_read_prop(struct udevice *dev,
562 					const char *propname, int *lenp)
563 {
564 	return ofnode_get_property(dev_ofnode(dev), propname, lenp);
565 }
566 
567 static inline int dev_read_alias_seq(struct udevice *dev, int *devnump)
568 {
569 	return fdtdec_get_alias_seq(gd->fdt_blob, dev->uclass->uc_drv->name,
570 				    dev_of_offset(dev), devnump);
571 }
572 
573 static inline int dev_read_u32_array(struct udevice *dev, const char *propname,
574 				     u32 *out_values, size_t sz)
575 {
576 	return ofnode_read_u32_array(dev_ofnode(dev), propname, out_values, sz);
577 }
578 
579 static inline ofnode dev_read_first_subnode(struct udevice *dev)
580 {
581 	return ofnode_first_subnode(dev_ofnode(dev));
582 }
583 
584 static inline ofnode dev_read_next_subnode(ofnode node)
585 {
586 	return ofnode_next_subnode(node);
587 }
588 
589 static inline const uint8_t *dev_read_u8_array_ptr(struct udevice *dev,
590 					const char *propname, size_t sz)
591 {
592 	return ofnode_read_u8_array_ptr(dev_ofnode(dev), propname, sz);
593 }
594 
595 static inline int dev_read_enabled(struct udevice *dev)
596 {
597 	return fdtdec_get_is_enabled(gd->fdt_blob, dev_of_offset(dev));
598 }
599 
600 static inline int dev_read_resource(struct udevice *dev, uint index,
601 				    struct resource *res)
602 {
603 	return ofnode_read_resource(dev_ofnode(dev), index, res);
604 }
605 
606 static inline int dev_read_resource_byname(struct udevice *dev,
607 					   const char *name,
608 					   struct resource *res)
609 {
610 	return ofnode_read_resource_byname(dev_ofnode(dev), name, res);
611 }
612 
613 static inline u64 dev_translate_address(struct udevice *dev, const fdt32_t *in_addr)
614 {
615 	return ofnode_translate_address(dev_ofnode(dev), in_addr);
616 }
617 
618 #endif /* CONFIG_DM_DEV_READ_INLINE */
619 
620 /**
621  * dev_for_each_subnode() - Helper function to iterate through subnodes
622  *
623  * This creates a for() loop which works through the subnodes in a device's
624  * device-tree node.
625  *
626  * @subnode: ofnode holding the current subnode
627  * @dev: device to use for interation (struct udevice *)
628  */
629 #define dev_for_each_subnode(subnode, dev) \
630 	for (subnode = dev_read_first_subnode(dev); \
631 	     ofnode_valid(subnode); \
632 	     subnode = ofnode_next_subnode(subnode))
633 
634 #endif
635