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mdio-sun4i: oops in error handling in probe
[linux/fpc-iii.git] / drivers / of / address.c
blob5af2a0deff14aca546f963a9cb5d51cd8aa22dd3
1
2 #include <linux/device.h>
3 #include <linux/io.h>
4 #include <linux/ioport.h>
5 #include <linux/module.h>
6 #include <linux/of_address.h>
7 #include <linux/pci_regs.h>
8 #include <linux/string.h>
9
10 /* Max address size we deal with */
11 #define OF_MAX_ADDR_CELLS 4
12 #define OF_CHECK_ADDR_COUNT(na) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
13 #define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
14
15 static struct of_bus *of_match_bus(struct device_node *np);
16 static int __of_address_to_resource(struct device_node *dev,
17 const __be32 *addrp, u64 size, unsigned int flags,
18 const char *name, struct resource *r);
19
20 /* Debug utility */
21 #ifdef DEBUG
22 static void of_dump_addr(const char *s, const __be32 *addr, int na)
23 {
24 printk(KERN_DEBUG "%s", s);
25 while (na--)
26 printk(" %08x", be32_to_cpu(*(addr++)));
27 printk("\n");
28 }
29 #else
30 static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
31 #endif
32
33 /* Callbacks for bus specific translators */
34 struct of_bus {
35 const char *name;
36 const char *addresses;
37 int (*match)(struct device_node *parent);
38 void (*count_cells)(struct device_node *child,
39 int *addrc, int *sizec);
40 u64 (*map)(__be32 *addr, const __be32 *range,
41 int na, int ns, int pna);
42 int (*translate)(__be32 *addr, u64 offset, int na);
43 unsigned int (*get_flags)(const __be32 *addr);
44 };
45
46 /*
47 * Default translator (generic bus)
48 */
49
50 static void of_bus_default_count_cells(struct device_node *dev,
51 int *addrc, int *sizec)
52 {
53 if (addrc)
54 *addrc = of_n_addr_cells(dev);
55 if (sizec)
56 *sizec = of_n_size_cells(dev);
57 }
58
59 static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
60 int na, int ns, int pna)
61 {
62 u64 cp, s, da;
63
64 cp = of_read_number(range, na);
65 s = of_read_number(range + na + pna, ns);
66 da = of_read_number(addr, na);
67
68 pr_debug("OF: default map, cp=%llx, s=%llx, da=%llx\n",
69 (unsigned long long)cp, (unsigned long long)s,
70 (unsigned long long)da);
71
72 if (da < cp || da >= (cp + s))
73 return OF_BAD_ADDR;
74 return da - cp;
75 }
76
77 static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
78 {
79 u64 a = of_read_number(addr, na);
80 memset(addr, 0, na * 4);
81 a += offset;
82 if (na > 1)
83 addr[na - 2] = cpu_to_be32(a >> 32);
84 addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
85
86 return 0;
87 }
88
89 static unsigned int of_bus_default_get_flags(const __be32 *addr)
90 {
91 return IORESOURCE_MEM;
92 }
93
94 #ifdef CONFIG_OF_ADDRESS_PCI
95 /*
96 * PCI bus specific translator
97 */
98
99 static int of_bus_pci_match(struct device_node *np)
100 {
101 /*
102 * "pciex" is PCI Express
103 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
104 * "ht" is hypertransport
105 */
106 return !strcmp(np->type, "pci") || !strcmp(np->type, "pciex") ||
107 !strcmp(np->type, "vci") || !strcmp(np->type, "ht");
108 }
109
110 static void of_bus_pci_count_cells(struct device_node *np,
111 int *addrc, int *sizec)
112 {
113 if (addrc)
114 *addrc = 3;
115 if (sizec)
116 *sizec = 2;
117 }
118
119 static unsigned int of_bus_pci_get_flags(const __be32 *addr)
120 {
121 unsigned int flags = 0;
122 u32 w = be32_to_cpup(addr);
123
124 switch((w >> 24) & 0x03) {
125 case 0x01:
126 flags |= IORESOURCE_IO;
127 break;
128 case 0x02: /* 32 bits */
129 case 0x03: /* 64 bits */
130 flags |= IORESOURCE_MEM;
131 break;
132 }
133 if (w & 0x40000000)
134 flags |= IORESOURCE_PREFETCH;
135 return flags;
136 }
137
138 static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
139 int pna)
140 {
141 u64 cp, s, da;
142 unsigned int af, rf;
143
144 af = of_bus_pci_get_flags(addr);
145 rf = of_bus_pci_get_flags(range);
146
147 /* Check address type match */
148 if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
149 return OF_BAD_ADDR;
150
151 /* Read address values, skipping high cell */
152 cp = of_read_number(range + 1, na - 1);
153 s = of_read_number(range + na + pna, ns);
154 da = of_read_number(addr + 1, na - 1);
155
156 pr_debug("OF: PCI map, cp=%llx, s=%llx, da=%llx\n",
157 (unsigned long long)cp, (unsigned long long)s,
158 (unsigned long long)da);
159
160 if (da < cp || da >= (cp + s))
161 return OF_BAD_ADDR;
162 return da - cp;
163 }
164
165 static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
166 {
167 return of_bus_default_translate(addr + 1, offset, na - 1);
168 }
169 #endif /* CONFIG_OF_ADDRESS_PCI */
170
171 #ifdef CONFIG_PCI
172 const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
173 unsigned int *flags)
174 {
175 const __be32 *prop;
176 unsigned int psize;
177 struct device_node *parent;
178 struct of_bus *bus;
179 int onesize, i, na, ns;
180
181 /* Get parent & match bus type */
182 parent = of_get_parent(dev);
183 if (parent == NULL)
184 return NULL;
185 bus = of_match_bus(parent);
186 if (strcmp(bus->name, "pci")) {
187 of_node_put(parent);
188 return NULL;
189 }
190 bus->count_cells(dev, &na, &ns);
191 of_node_put(parent);
192 if (!OF_CHECK_ADDR_COUNT(na))
193 return NULL;
194
195 /* Get "reg" or "assigned-addresses" property */
196 prop = of_get_property(dev, bus->addresses, &psize);
197 if (prop == NULL)
198 return NULL;
199 psize /= 4;
200
201 onesize = na + ns;
202 for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
203 u32 val = be32_to_cpu(prop[0]);
204 if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
205 if (size)
206 *size = of_read_number(prop + na, ns);
207 if (flags)
208 *flags = bus->get_flags(prop);
209 return prop;
210 }
211 }
212 return NULL;
213 }
214 EXPORT_SYMBOL(of_get_pci_address);
215
216 int of_pci_address_to_resource(struct device_node *dev, int bar,
217 struct resource *r)
218 {
219 const __be32 *addrp;
220 u64 size;
221 unsigned int flags;
222
223 addrp = of_get_pci_address(dev, bar, &size, &flags);
224 if (addrp == NULL)
225 return -EINVAL;
226 return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
227 }
228 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
229
230 int of_pci_range_parser_init(struct of_pci_range_parser *parser,
231 struct device_node *node)
232 {
233 const int na = 3, ns = 2;
234 int rlen;
235
236 parser->node = node;
237 parser->pna = of_n_addr_cells(node);
238 parser->np = parser->pna + na + ns;
239
240 parser->range = of_get_property(node, "ranges", &rlen);
241 if (parser->range == NULL)
242 return -ENOENT;
243
244 parser->end = parser->range + rlen / sizeof(__be32);
245
246 return 0;
247 }
248 EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
249
250 struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
251 struct of_pci_range *range)
252 {
253 const int na = 3, ns = 2;
254
255 if (!range)
256 return NULL;
257
258 if (!parser->range || parser->range + parser->np > parser->end)
259 return NULL;
260
261 range->pci_space = parser->range[0];
262 range->flags = of_bus_pci_get_flags(parser->range);
263 range->pci_addr = of_read_number(parser->range + 1, ns);
264 range->cpu_addr = of_translate_address(parser->node,
265 parser->range + na);
266 range->size = of_read_number(parser->range + parser->pna + na, ns);
267
268 parser->range += parser->np;
269
270 /* Now consume following elements while they are contiguous */
271 while (parser->range + parser->np <= parser->end) {
272 u32 flags, pci_space;
273 u64 pci_addr, cpu_addr, size;
274
275 pci_space = be32_to_cpup(parser->range);
276 flags = of_bus_pci_get_flags(parser->range);
277 pci_addr = of_read_number(parser->range + 1, ns);
278 cpu_addr = of_translate_address(parser->node,
279 parser->range + na);
280 size = of_read_number(parser->range + parser->pna + na, ns);
281
282 if (flags != range->flags)
283 break;
284 if (pci_addr != range->pci_addr + range->size ||
285 cpu_addr != range->cpu_addr + range->size)
286 break;
287
288 range->size += size;
289 parser->range += parser->np;
290 }
291
292 return range;
293 }
294 EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
295
296 #endif /* CONFIG_PCI */
297
298 /*
299 * ISA bus specific translator
300 */
301
302 static int of_bus_isa_match(struct device_node *np)
303 {
304 return !strcmp(np->name, "isa");
305 }
306
307 static void of_bus_isa_count_cells(struct device_node *child,
308 int *addrc, int *sizec)
309 {
310 if (addrc)
311 *addrc = 2;
312 if (sizec)
313 *sizec = 1;
314 }
315
316 static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
317 int pna)
318 {
319 u64 cp, s, da;
320
321 /* Check address type match */
322 if ((addr[0] ^ range[0]) & cpu_to_be32(1))
323 return OF_BAD_ADDR;
324
325 /* Read address values, skipping high cell */
326 cp = of_read_number(range + 1, na - 1);
327 s = of_read_number(range + na + pna, ns);
328 da = of_read_number(addr + 1, na - 1);
329
330 pr_debug("OF: ISA map, cp=%llx, s=%llx, da=%llx\n",
331 (unsigned long long)cp, (unsigned long long)s,
332 (unsigned long long)da);
333
334 if (da < cp || da >= (cp + s))
335 return OF_BAD_ADDR;
336 return da - cp;
337 }
338
339 static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
340 {
341 return of_bus_default_translate(addr + 1, offset, na - 1);
342 }
343
344 static unsigned int of_bus_isa_get_flags(const __be32 *addr)
345 {
346 unsigned int flags = 0;
347 u32 w = be32_to_cpup(addr);
348
349 if (w & 1)
350 flags |= IORESOURCE_IO;
351 else
352 flags |= IORESOURCE_MEM;
353 return flags;
354 }
355
356 /*
357 * Array of bus specific translators
358 */
359
360 static struct of_bus of_busses[] = {
361 #ifdef CONFIG_OF_ADDRESS_PCI
362 /* PCI */
363 {
364 .name = "pci",
365 .addresses = "assigned-addresses",
366 .match = of_bus_pci_match,
367 .count_cells = of_bus_pci_count_cells,
368 .map = of_bus_pci_map,
369 .translate = of_bus_pci_translate,
370 .get_flags = of_bus_pci_get_flags,
371 },
372 #endif /* CONFIG_OF_ADDRESS_PCI */
373 /* ISA */
374 {
375 .name = "isa",
376 .addresses = "reg",
377 .match = of_bus_isa_match,
378 .count_cells = of_bus_isa_count_cells,
379 .map = of_bus_isa_map,
380 .translate = of_bus_isa_translate,
381 .get_flags = of_bus_isa_get_flags,
382 },
383 /* Default */
384 {
385 .name = "default",
386 .addresses = "reg",
387 .match = NULL,
388 .count_cells = of_bus_default_count_cells,
389 .map = of_bus_default_map,
390 .translate = of_bus_default_translate,
391 .get_flags = of_bus_default_get_flags,
392 },
393 };
394
395 static struct of_bus *of_match_bus(struct device_node *np)
396 {
397 int i;
398
399 for (i = 0; i < ARRAY_SIZE(of_busses); i++)
400 if (!of_busses[i].match || of_busses[i].match(np))
401 return &of_busses[i];
402 BUG();
403 return NULL;
404 }
405
406 static int of_empty_ranges_quirk(struct device_node *np)
407 {
408 if (IS_ENABLED(CONFIG_PPC)) {
409 /* To save cycles, we cache the result for global "Mac" setting */
410 static int quirk_state = -1;
411
412 /* PA-SEMI sdc DT bug */
413 if (of_device_is_compatible(np, "1682m-sdc"))
414 return true;
415
416 /* Make quirk cached */
417 if (quirk_state < 0)
418 quirk_state =
419 of_machine_is_compatible("Power Macintosh") ||
420 of_machine_is_compatible("MacRISC");
421 return quirk_state;
422 }
423 return false;
424 }
425
426 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
427 struct of_bus *pbus, __be32 *addr,
428 int na, int ns, int pna, const char *rprop)
429 {
430 const __be32 *ranges;
431 unsigned int rlen;
432 int rone;
433 u64 offset = OF_BAD_ADDR;
434
435 /* Normally, an absence of a "ranges" property means we are
436 * crossing a non-translatable boundary, and thus the addresses
437 * below the current not cannot be converted to CPU physical ones.
438 * Unfortunately, while this is very clear in the spec, it's not
439 * what Apple understood, and they do have things like /uni-n or
440 * /ht nodes with no "ranges" property and a lot of perfectly
441 * useable mapped devices below them. Thus we treat the absence of
442 * "ranges" as equivalent to an empty "ranges" property which means
443 * a 1:1 translation at that level. It's up to the caller not to try
444 * to translate addresses that aren't supposed to be translated in
445 * the first place. --BenH.
446 *
447 * As far as we know, this damage only exists on Apple machines, so
448 * This code is only enabled on powerpc. --gcl
449 */
450 ranges = of_get_property(parent, rprop, &rlen);
451 if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
452 pr_err("OF: no ranges; cannot translate\n");
453 return 1;
454 }
455 if (ranges == NULL || rlen == 0) {
456 offset = of_read_number(addr, na);
457 memset(addr, 0, pna * 4);
458 pr_debug("OF: empty ranges; 1:1 translation\n");
459 goto finish;
460 }
461
462 pr_debug("OF: walking ranges...\n");
463
464 /* Now walk through the ranges */
465 rlen /= 4;
466 rone = na + pna + ns;
467 for (; rlen >= rone; rlen -= rone, ranges += rone) {
468 offset = bus->map(addr, ranges, na, ns, pna);
469 if (offset != OF_BAD_ADDR)
470 break;
471 }
472 if (offset == OF_BAD_ADDR) {
473 pr_debug("OF: not found !\n");
474 return 1;
475 }
476 memcpy(addr, ranges + na, 4 * pna);
477
478 finish:
479 of_dump_addr("OF: parent translation for:", addr, pna);
480 pr_debug("OF: with offset: %llx\n", (unsigned long long)offset);
481
482 /* Translate it into parent bus space */
483 return pbus->translate(addr, offset, pna);
484 }
485
486 /*
487 * Translate an address from the device-tree into a CPU physical address,
488 * this walks up the tree and applies the various bus mappings on the
489 * way.
490 *
491 * Note: We consider that crossing any level with #size-cells == 0 to mean
492 * that translation is impossible (that is we are not dealing with a value
493 * that can be mapped to a cpu physical address). This is not really specified
494 * that way, but this is traditionally the way IBM at least do things
495 */
496 static u64 __of_translate_address(struct device_node *dev,
497 const __be32 *in_addr, const char *rprop)
498 {
499 struct device_node *parent = NULL;
500 struct of_bus *bus, *pbus;
501 __be32 addr[OF_MAX_ADDR_CELLS];
502 int na, ns, pna, pns;
503 u64 result = OF_BAD_ADDR;
504
505 pr_debug("OF: ** translation for device %s **\n", of_node_full_name(dev));
506
507 /* Increase refcount at current level */
508 of_node_get(dev);
509
510 /* Get parent & match bus type */
511 parent = of_get_parent(dev);
512 if (parent == NULL)
513 goto bail;
514 bus = of_match_bus(parent);
515
516 /* Count address cells & copy address locally */
517 bus->count_cells(dev, &na, &ns);
518 if (!OF_CHECK_COUNTS(na, ns)) {
519 pr_debug("OF: Bad cell count for %s\n", of_node_full_name(dev));
520 goto bail;
521 }
522 memcpy(addr, in_addr, na * 4);
523
524 pr_debug("OF: bus is %s (na=%d, ns=%d) on %s\n",
525 bus->name, na, ns, of_node_full_name(parent));
526 of_dump_addr("OF: translating address:", addr, na);
527
528 /* Translate */
529 for (;;) {
530 /* Switch to parent bus */
531 of_node_put(dev);
532 dev = parent;
533 parent = of_get_parent(dev);
534
535 /* If root, we have finished */
536 if (parent == NULL) {
537 pr_debug("OF: reached root node\n");
538 result = of_read_number(addr, na);
539 break;
540 }
541
542 /* Get new parent bus and counts */
543 pbus = of_match_bus(parent);
544 pbus->count_cells(dev, &pna, &pns);
545 if (!OF_CHECK_COUNTS(pna, pns)) {
546 printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
547 of_node_full_name(dev));
548 break;
549 }
550
551 pr_debug("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
552 pbus->name, pna, pns, of_node_full_name(parent));
553
554 /* Apply bus translation */
555 if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
556 break;
557
558 /* Complete the move up one level */
559 na = pna;
560 ns = pns;
561 bus = pbus;
562
563 of_dump_addr("OF: one level translation:", addr, na);
564 }
565 bail:
566 of_node_put(parent);
567 of_node_put(dev);
568
569 return result;
570 }
571
572 u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
573 {
574 return __of_translate_address(dev, in_addr, "ranges");
575 }
576 EXPORT_SYMBOL(of_translate_address);
577
578 u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
579 {
580 return __of_translate_address(dev, in_addr, "dma-ranges");
581 }
582 EXPORT_SYMBOL(of_translate_dma_address);
583
584 const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
585 unsigned int *flags)
586 {
587 const __be32 *prop;
588 unsigned int psize;
589 struct device_node *parent;
590 struct of_bus *bus;
591 int onesize, i, na, ns;
592
593 /* Get parent & match bus type */
594 parent = of_get_parent(dev);
595 if (parent == NULL)
596 return NULL;
597 bus = of_match_bus(parent);
598 bus->count_cells(dev, &na, &ns);
599 of_node_put(parent);
600 if (!OF_CHECK_ADDR_COUNT(na))
601 return NULL;
602
603 /* Get "reg" or "assigned-addresses" property */
604 prop = of_get_property(dev, bus->addresses, &psize);
605 if (prop == NULL)
606 return NULL;
607 psize /= 4;
608
609 onesize = na + ns;
610 for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
611 if (i == index) {
612 if (size)
613 *size = of_read_number(prop + na, ns);
614 if (flags)
615 *flags = bus->get_flags(prop);
616 return prop;
617 }
618 return NULL;
619 }
620 EXPORT_SYMBOL(of_get_address);
621
622 unsigned long __weak pci_address_to_pio(phys_addr_t address)
623 {
624 if (address > IO_SPACE_LIMIT)
625 return (unsigned long)-1;
626
627 return (unsigned long) address;
628 }
629
630 static int __of_address_to_resource(struct device_node *dev,
631 const __be32 *addrp, u64 size, unsigned int flags,
632 const char *name, struct resource *r)
633 {
634 u64 taddr;
635
636 if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
637 return -EINVAL;
638 taddr = of_translate_address(dev, addrp);
639 if (taddr == OF_BAD_ADDR)
640 return -EINVAL;
641 memset(r, 0, sizeof(struct resource));
642 if (flags & IORESOURCE_IO) {
643 unsigned long port;
644 port = pci_address_to_pio(taddr);
645 if (port == (unsigned long)-1)
646 return -EINVAL;
647 r->start = port;
648 r->end = port + size - 1;
649 } else {
650 r->start = taddr;
651 r->end = taddr + size - 1;
652 }
653 r->flags = flags;
654 r->name = name ? name : dev->full_name;
655
656 return 0;
657 }
658
659 /**
660 * of_address_to_resource - Translate device tree address and return as resource
661 *
662 * Note that if your address is a PIO address, the conversion will fail if
663 * the physical address can't be internally converted to an IO token with
664 * pci_address_to_pio(), that is because it's either called to early or it
665 * can't be matched to any host bridge IO space
666 */
667 int of_address_to_resource(struct device_node *dev, int index,
668 struct resource *r)
669 {
670 const __be32 *addrp;
671 u64 size;
672 unsigned int flags;
673 const char *name = NULL;
674
675 addrp = of_get_address(dev, index, &size, &flags);
676 if (addrp == NULL)
677 return -EINVAL;
678
679 /* Get optional "reg-names" property to add a name to a resource */
680 of_property_read_string_index(dev, "reg-names", index, &name);
681
682 return __of_address_to_resource(dev, addrp, size, flags, name, r);
683 }
684 EXPORT_SYMBOL_GPL(of_address_to_resource);
685
686 struct device_node *of_find_matching_node_by_address(struct device_node *from,
687 const struct of_device_id *matches,
688 u64 base_address)
689 {
690 struct device_node *dn = of_find_matching_node(from, matches);
691 struct resource res;
692
693 while (dn) {
694 if (!of_address_to_resource(dn, 0, &res) &&
695 res.start == base_address)
696 return dn;
697
698 dn = of_find_matching_node(dn, matches);
699 }
700
701 return NULL;
702 }
703
704
705 /**
706 * of_iomap - Maps the memory mapped IO for a given device_node
707 * @device: the device whose io range will be mapped
708 * @index: index of the io range
709 *
710 * Returns a pointer to the mapped memory
711 */
712 void __iomem *of_iomap(struct device_node *np, int index)
713 {
714 struct resource res;
715
716 if (of_address_to_resource(np, index, &res))
717 return NULL;
718
719 return ioremap(res.start, resource_size(&res));
720 }
721 EXPORT_SYMBOL(of_iomap);
722
723 /**
724 * of_dma_get_range - Get DMA range info
725 * @np: device node to get DMA range info
726 * @dma_addr: pointer to store initial DMA address of DMA range
727 * @paddr: pointer to store initial CPU address of DMA range
728 * @size: pointer to store size of DMA range
729 *
730 * Look in bottom up direction for the first "dma-ranges" property
731 * and parse it.
732 * dma-ranges format:
733 * DMA addr (dma_addr) : naddr cells
734 * CPU addr (phys_addr_t) : pna cells
735 * size : nsize cells
736 *
737 * It returns -ENODEV if "dma-ranges" property was not found
738 * for this device in DT.
739 */
740 int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
741 {
742 struct device_node *node = of_node_get(np);
743 const __be32 *ranges = NULL;
744 int len, naddr, nsize, pna;
745 int ret = 0;
746 u64 dmaaddr;
747
748 if (!node)
749 return -EINVAL;
750
751 while (1) {
752 naddr = of_n_addr_cells(node);
753 nsize = of_n_size_cells(node);
754 node = of_get_next_parent(node);
755 if (!node)
756 break;
757
758 ranges = of_get_property(node, "dma-ranges", &len);
759
760 /* Ignore empty ranges, they imply no translation required */
761 if (ranges && len > 0)
762 break;
763
764 /*
765 * At least empty ranges has to be defined for parent node if
766 * DMA is supported
767 */
768 if (!ranges)
769 break;
770 }
771
772 if (!ranges) {
773 pr_debug("%s: no dma-ranges found for node(%s)\n",
774 __func__, np->full_name);
775 ret = -ENODEV;
776 goto out;
777 }
778
779 len /= sizeof(u32);
780
781 pna = of_n_addr_cells(node);
782
783 /* dma-ranges format:
784 * DMA addr : naddr cells
785 * CPU addr : pna cells
786 * size : nsize cells
787 */
788 dmaaddr = of_read_number(ranges, naddr);
789 *paddr = of_translate_dma_address(np, ranges);
790 if (*paddr == OF_BAD_ADDR) {
791 pr_err("%s: translation of DMA address(%pad) to CPU address failed node(%s)\n",
792 __func__, dma_addr, np->full_name);
793 ret = -EINVAL;
794 goto out;
795 }
796 *dma_addr = dmaaddr;
797
798 *size = of_read_number(ranges + naddr + pna, nsize);
799
800 pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
801 *dma_addr, *paddr, *size);
802
803 out:
804 of_node_put(node);
805
806 return ret;
807 }
808 EXPORT_SYMBOL_GPL(of_dma_get_range);
809
810 /**
811 * of_dma_is_coherent - Check if device is coherent
812 * @np: device node
813 *
814 * It returns true if "dma-coherent" property was found
815 * for this device in DT.
816 */
817 bool of_dma_is_coherent(struct device_node *np)
818 {
819 struct device_node *node = of_node_get(np);
820
821 while (node) {
822 if (of_property_read_bool(node, "dma-coherent")) {
823 of_node_put(node);
824 return true;
825 }
826 node = of_get_next_parent(node);
827 }
828 of_node_put(node);
829 return false;
830 }
831 EXPORT_SYMBOL_GPL(of_dma_is_coherent);
Linux with added FPC-III support