xref: /openbmc/linux/drivers/of/address.c (revision 61ae993c)
1 // SPDX-License-Identifier: GPL-2.0
2 #define pr_fmt(fmt)	"OF: " fmt
3 
4 #include <linux/device.h>
5 #include <linux/fwnode.h>
6 #include <linux/io.h>
7 #include <linux/ioport.h>
8 #include <linux/logic_pio.h>
9 #include <linux/module.h>
10 #include <linux/of_address.h>
11 #include <linux/pci.h>
12 #include <linux/pci_regs.h>
13 #include <linux/sizes.h>
14 #include <linux/slab.h>
15 #include <linux/string.h>
16 #include <linux/dma-direct.h> /* for bus_dma_region */
17 
18 #include "of_private.h"
19 
20 /* Max address size we deal with */
21 #define OF_MAX_ADDR_CELLS	4
22 #define OF_CHECK_ADDR_COUNT(na)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
23 #define OF_CHECK_COUNTS(na, ns)	(OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
24 
25 /* Debug utility */
26 #ifdef DEBUG
27 static void of_dump_addr(const char *s, const __be32 *addr, int na)
28 {
29 	pr_debug("%s", s);
30 	while (na--)
31 		pr_cont(" %08x", be32_to_cpu(*(addr++)));
32 	pr_cont("\n");
33 }
34 #else
35 static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
36 #endif
37 
38 /* Callbacks for bus specific translators */
39 struct of_bus {
40 	const char	*name;
41 	const char	*addresses;
42 	int		(*match)(struct device_node *parent);
43 	void		(*count_cells)(struct device_node *child,
44 				       int *addrc, int *sizec);
45 	u64		(*map)(__be32 *addr, const __be32 *range,
46 				int na, int ns, int pna);
47 	int		(*translate)(__be32 *addr, u64 offset, int na);
48 	bool	has_flags;
49 	unsigned int	(*get_flags)(const __be32 *addr);
50 };
51 
52 /*
53  * Default translator (generic bus)
54  */
55 
56 static void of_bus_default_count_cells(struct device_node *dev,
57 				       int *addrc, int *sizec)
58 {
59 	if (addrc)
60 		*addrc = of_n_addr_cells(dev);
61 	if (sizec)
62 		*sizec = of_n_size_cells(dev);
63 }
64 
65 static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
66 		int na, int ns, int pna)
67 {
68 	u64 cp, s, da;
69 
70 	cp = of_read_number(range, na);
71 	s  = of_read_number(range + na + pna, ns);
72 	da = of_read_number(addr, na);
73 
74 	pr_debug("default map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);
75 
76 	if (da < cp || da >= (cp + s))
77 		return OF_BAD_ADDR;
78 	return da - cp;
79 }
80 
81 static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
82 {
83 	u64 a = of_read_number(addr, na);
84 	memset(addr, 0, na * 4);
85 	a += offset;
86 	if (na > 1)
87 		addr[na - 2] = cpu_to_be32(a >> 32);
88 	addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
89 
90 	return 0;
91 }
92 
93 static unsigned int of_bus_default_flags_get_flags(const __be32 *addr)
94 {
95 	return of_read_number(addr, 1);
96 }
97 
98 static unsigned int of_bus_default_get_flags(const __be32 *addr)
99 {
100 	return IORESOURCE_MEM;
101 }
102 
103 static u64 of_bus_default_flags_map(__be32 *addr, const __be32 *range, int na,
104 				    int ns, int pna)
105 {
106 	u64 cp, s, da;
107 
108 	/* Check that flags match */
109 	if (*addr != *range)
110 		return OF_BAD_ADDR;
111 
112 	/* Read address values, skipping high cell */
113 	cp = of_read_number(range + 1, na - 1);
114 	s  = of_read_number(range + na + pna, ns);
115 	da = of_read_number(addr + 1, na - 1);
116 
117 	pr_debug("default flags map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);
118 
119 	if (da < cp || da >= (cp + s))
120 		return OF_BAD_ADDR;
121 	return da - cp;
122 }
123 
124 static int of_bus_default_flags_translate(__be32 *addr, u64 offset, int na)
125 {
126 	/* Keep "flags" part (high cell) in translated address */
127 	return of_bus_default_translate(addr + 1, offset, na - 1);
128 }
129 
130 #ifdef CONFIG_PCI
131 static unsigned int of_bus_pci_get_flags(const __be32 *addr)
132 {
133 	unsigned int flags = 0;
134 	u32 w = be32_to_cpup(addr);
135 
136 	if (!IS_ENABLED(CONFIG_PCI))
137 		return 0;
138 
139 	switch((w >> 24) & 0x03) {
140 	case 0x01:
141 		flags |= IORESOURCE_IO;
142 		break;
143 	case 0x02: /* 32 bits */
144 		flags |= IORESOURCE_MEM;
145 		break;
146 
147 	case 0x03: /* 64 bits */
148 		flags |= IORESOURCE_MEM | IORESOURCE_MEM_64;
149 		break;
150 	}
151 	if (w & 0x40000000)
152 		flags |= IORESOURCE_PREFETCH;
153 	return flags;
154 }
155 
156 /*
157  * PCI bus specific translator
158  */
159 
160 static bool of_node_is_pcie(struct device_node *np)
161 {
162 	bool is_pcie = of_node_name_eq(np, "pcie");
163 
164 	if (is_pcie)
165 		pr_warn_once("%pOF: Missing device_type\n", np);
166 
167 	return is_pcie;
168 }
169 
170 static int of_bus_pci_match(struct device_node *np)
171 {
172 	/*
173  	 * "pciex" is PCI Express
174 	 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
175 	 * "ht" is hypertransport
176 	 *
177 	 * If none of the device_type match, and that the node name is
178 	 * "pcie", accept the device as PCI (with a warning).
179 	 */
180 	return of_node_is_type(np, "pci") || of_node_is_type(np, "pciex") ||
181 		of_node_is_type(np, "vci") || of_node_is_type(np, "ht") ||
182 		of_node_is_pcie(np);
183 }
184 
185 static void of_bus_pci_count_cells(struct device_node *np,
186 				   int *addrc, int *sizec)
187 {
188 	if (addrc)
189 		*addrc = 3;
190 	if (sizec)
191 		*sizec = 2;
192 }
193 
194 static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
195 		int pna)
196 {
197 	u64 cp, s, da;
198 	unsigned int af, rf;
199 
200 	af = of_bus_pci_get_flags(addr);
201 	rf = of_bus_pci_get_flags(range);
202 
203 	/* Check address type match */
204 	if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
205 		return OF_BAD_ADDR;
206 
207 	/* Read address values, skipping high cell */
208 	cp = of_read_number(range + 1, na - 1);
209 	s  = of_read_number(range + na + pna, ns);
210 	da = of_read_number(addr + 1, na - 1);
211 
212 	pr_debug("PCI map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);
213 
214 	if (da < cp || da >= (cp + s))
215 		return OF_BAD_ADDR;
216 	return da - cp;
217 }
218 
219 static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
220 {
221 	return of_bus_default_translate(addr + 1, offset, na - 1);
222 }
223 #endif /* CONFIG_PCI */
224 
225 /*
226  * of_pci_range_to_resource - Create a resource from an of_pci_range
227  * @range:	the PCI range that describes the resource
228  * @np:		device node where the range belongs to
229  * @res:	pointer to a valid resource that will be updated to
230  *              reflect the values contained in the range.
231  *
232  * Returns -EINVAL if the range cannot be converted to resource.
233  *
234  * Note that if the range is an IO range, the resource will be converted
235  * using pci_address_to_pio() which can fail if it is called too early or
236  * if the range cannot be matched to any host bridge IO space (our case here).
237  * To guard against that we try to register the IO range first.
238  * If that fails we know that pci_address_to_pio() will do too.
239  */
240 int of_pci_range_to_resource(struct of_pci_range *range,
241 			     struct device_node *np, struct resource *res)
242 {
243 	int err;
244 	res->flags = range->flags;
245 	res->parent = res->child = res->sibling = NULL;
246 	res->name = np->full_name;
247 
248 	if (res->flags & IORESOURCE_IO) {
249 		unsigned long port;
250 		err = pci_register_io_range(&np->fwnode, range->cpu_addr,
251 				range->size);
252 		if (err)
253 			goto invalid_range;
254 		port = pci_address_to_pio(range->cpu_addr);
255 		if (port == (unsigned long)-1) {
256 			err = -EINVAL;
257 			goto invalid_range;
258 		}
259 		res->start = port;
260 	} else {
261 		if ((sizeof(resource_size_t) < 8) &&
262 		    upper_32_bits(range->cpu_addr)) {
263 			err = -EINVAL;
264 			goto invalid_range;
265 		}
266 
267 		res->start = range->cpu_addr;
268 	}
269 	res->end = res->start + range->size - 1;
270 	return 0;
271 
272 invalid_range:
273 	res->start = (resource_size_t)OF_BAD_ADDR;
274 	res->end = (resource_size_t)OF_BAD_ADDR;
275 	return err;
276 }
277 EXPORT_SYMBOL(of_pci_range_to_resource);
278 
279 /*
280  * of_range_to_resource - Create a resource from a ranges entry
281  * @np:		device node where the range belongs to
282  * @index:	the 'ranges' index to convert to a resource
283  * @res:	pointer to a valid resource that will be updated to
284  *              reflect the values contained in the range.
285  *
286  * Returns ENOENT if the entry is not found or EINVAL if the range cannot be
287  * converted to resource.
288  */
289 int of_range_to_resource(struct device_node *np, int index, struct resource *res)
290 {
291 	int ret, i = 0;
292 	struct of_range_parser parser;
293 	struct of_range range;
294 
295 	ret = of_range_parser_init(&parser, np);
296 	if (ret)
297 		return ret;
298 
299 	for_each_of_range(&parser, &range)
300 		if (i++ == index)
301 			return of_pci_range_to_resource(&range, np, res);
302 
303 	return -ENOENT;
304 }
305 EXPORT_SYMBOL(of_range_to_resource);
306 
307 /*
308  * ISA bus specific translator
309  */
310 
311 static int of_bus_isa_match(struct device_node *np)
312 {
313 	return of_node_name_eq(np, "isa");
314 }
315 
316 static void of_bus_isa_count_cells(struct device_node *child,
317 				   int *addrc, int *sizec)
318 {
319 	if (addrc)
320 		*addrc = 2;
321 	if (sizec)
322 		*sizec = 1;
323 }
324 
325 static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
326 		int pna)
327 {
328 	u64 cp, s, da;
329 
330 	/* Check address type match */
331 	if ((addr[0] ^ range[0]) & cpu_to_be32(1))
332 		return OF_BAD_ADDR;
333 
334 	/* Read address values, skipping high cell */
335 	cp = of_read_number(range + 1, na - 1);
336 	s  = of_read_number(range + na + pna, ns);
337 	da = of_read_number(addr + 1, na - 1);
338 
339 	pr_debug("ISA map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);
340 
341 	if (da < cp || da >= (cp + s))
342 		return OF_BAD_ADDR;
343 	return da - cp;
344 }
345 
346 static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
347 {
348 	return of_bus_default_translate(addr + 1, offset, na - 1);
349 }
350 
351 static unsigned int of_bus_isa_get_flags(const __be32 *addr)
352 {
353 	unsigned int flags = 0;
354 	u32 w = be32_to_cpup(addr);
355 
356 	if (w & 1)
357 		flags |= IORESOURCE_IO;
358 	else
359 		flags |= IORESOURCE_MEM;
360 	return flags;
361 }
362 
363 static int of_bus_default_flags_match(struct device_node *np)
364 {
365 	return of_bus_n_addr_cells(np) == 3;
366 }
367 
368 /*
369  * Array of bus specific translators
370  */
371 
372 static struct of_bus of_busses[] = {
373 #ifdef CONFIG_PCI
374 	/* PCI */
375 	{
376 		.name = "pci",
377 		.addresses = "assigned-addresses",
378 		.match = of_bus_pci_match,
379 		.count_cells = of_bus_pci_count_cells,
380 		.map = of_bus_pci_map,
381 		.translate = of_bus_pci_translate,
382 		.has_flags = true,
383 		.get_flags = of_bus_pci_get_flags,
384 	},
385 #endif /* CONFIG_PCI */
386 	/* ISA */
387 	{
388 		.name = "isa",
389 		.addresses = "reg",
390 		.match = of_bus_isa_match,
391 		.count_cells = of_bus_isa_count_cells,
392 		.map = of_bus_isa_map,
393 		.translate = of_bus_isa_translate,
394 		.has_flags = true,
395 		.get_flags = of_bus_isa_get_flags,
396 	},
397 	/* Default with flags cell */
398 	{
399 		.name = "default-flags",
400 		.addresses = "reg",
401 		.match = of_bus_default_flags_match,
402 		.count_cells = of_bus_default_count_cells,
403 		.map = of_bus_default_flags_map,
404 		.translate = of_bus_default_flags_translate,
405 		.has_flags = true,
406 		.get_flags = of_bus_default_flags_get_flags,
407 	},
408 	/* Default */
409 	{
410 		.name = "default",
411 		.addresses = "reg",
412 		.match = NULL,
413 		.count_cells = of_bus_default_count_cells,
414 		.map = of_bus_default_map,
415 		.translate = of_bus_default_translate,
416 		.get_flags = of_bus_default_get_flags,
417 	},
418 };
419 
420 static struct of_bus *of_match_bus(struct device_node *np)
421 {
422 	int i;
423 
424 	for (i = 0; i < ARRAY_SIZE(of_busses); i++)
425 		if (!of_busses[i].match || of_busses[i].match(np))
426 			return &of_busses[i];
427 	BUG();
428 	return NULL;
429 }
430 
431 static int of_empty_ranges_quirk(struct device_node *np)
432 {
433 	if (IS_ENABLED(CONFIG_PPC)) {
434 		/* To save cycles, we cache the result for global "Mac" setting */
435 		static int quirk_state = -1;
436 
437 		/* PA-SEMI sdc DT bug */
438 		if (of_device_is_compatible(np, "1682m-sdc"))
439 			return true;
440 
441 		/* Make quirk cached */
442 		if (quirk_state < 0)
443 			quirk_state =
444 				of_machine_is_compatible("Power Macintosh") ||
445 				of_machine_is_compatible("MacRISC");
446 		return quirk_state;
447 	}
448 	return false;
449 }
450 
451 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
452 			    struct of_bus *pbus, __be32 *addr,
453 			    int na, int ns, int pna, const char *rprop)
454 {
455 	const __be32 *ranges;
456 	unsigned int rlen;
457 	int rone;
458 	u64 offset = OF_BAD_ADDR;
459 
460 	/*
461 	 * Normally, an absence of a "ranges" property means we are
462 	 * crossing a non-translatable boundary, and thus the addresses
463 	 * below the current cannot be converted to CPU physical ones.
464 	 * Unfortunately, while this is very clear in the spec, it's not
465 	 * what Apple understood, and they do have things like /uni-n or
466 	 * /ht nodes with no "ranges" property and a lot of perfectly
467 	 * useable mapped devices below them. Thus we treat the absence of
468 	 * "ranges" as equivalent to an empty "ranges" property which means
469 	 * a 1:1 translation at that level. It's up to the caller not to try
470 	 * to translate addresses that aren't supposed to be translated in
471 	 * the first place. --BenH.
472 	 *
473 	 * As far as we know, this damage only exists on Apple machines, so
474 	 * This code is only enabled on powerpc. --gcl
475 	 *
476 	 * This quirk also applies for 'dma-ranges' which frequently exist in
477 	 * child nodes without 'dma-ranges' in the parent nodes. --RobH
478 	 */
479 	ranges = of_get_property(parent, rprop, &rlen);
480 	if (ranges == NULL && !of_empty_ranges_quirk(parent) &&
481 	    strcmp(rprop, "dma-ranges")) {
482 		pr_debug("no ranges; cannot translate\n");
483 		return 1;
484 	}
485 	if (ranges == NULL || rlen == 0) {
486 		offset = of_read_number(addr, na);
487 		memset(addr, 0, pna * 4);
488 		pr_debug("empty ranges; 1:1 translation\n");
489 		goto finish;
490 	}
491 
492 	pr_debug("walking ranges...\n");
493 
494 	/* Now walk through the ranges */
495 	rlen /= 4;
496 	rone = na + pna + ns;
497 	for (; rlen >= rone; rlen -= rone, ranges += rone) {
498 		offset = bus->map(addr, ranges, na, ns, pna);
499 		if (offset != OF_BAD_ADDR)
500 			break;
501 	}
502 	if (offset == OF_BAD_ADDR) {
503 		pr_debug("not found !\n");
504 		return 1;
505 	}
506 	memcpy(addr, ranges + na, 4 * pna);
507 
508  finish:
509 	of_dump_addr("parent translation for:", addr, pna);
510 	pr_debug("with offset: %llx\n", offset);
511 
512 	/* Translate it into parent bus space */
513 	return pbus->translate(addr, offset, pna);
514 }
515 
516 /*
517  * Translate an address from the device-tree into a CPU physical address,
518  * this walks up the tree and applies the various bus mappings on the
519  * way.
520  *
521  * Note: We consider that crossing any level with #size-cells == 0 to mean
522  * that translation is impossible (that is we are not dealing with a value
523  * that can be mapped to a cpu physical address). This is not really specified
524  * that way, but this is traditionally the way IBM at least do things
525  *
526  * Whenever the translation fails, the *host pointer will be set to the
527  * device that had registered logical PIO mapping, and the return code is
528  * relative to that node.
529  */
530 static u64 __of_translate_address(struct device_node *dev,
531 				  struct device_node *(*get_parent)(const struct device_node *),
532 				  const __be32 *in_addr, const char *rprop,
533 				  struct device_node **host)
534 {
535 	struct device_node *parent = NULL;
536 	struct of_bus *bus, *pbus;
537 	__be32 addr[OF_MAX_ADDR_CELLS];
538 	int na, ns, pna, pns;
539 	u64 result = OF_BAD_ADDR;
540 
541 	pr_debug("** translation for device %pOF **\n", dev);
542 
543 	/* Increase refcount at current level */
544 	of_node_get(dev);
545 
546 	*host = NULL;
547 	/* Get parent & match bus type */
548 	parent = get_parent(dev);
549 	if (parent == NULL)
550 		goto bail;
551 	bus = of_match_bus(parent);
552 
553 	/* Count address cells & copy address locally */
554 	bus->count_cells(dev, &na, &ns);
555 	if (!OF_CHECK_COUNTS(na, ns)) {
556 		pr_debug("Bad cell count for %pOF\n", dev);
557 		goto bail;
558 	}
559 	memcpy(addr, in_addr, na * 4);
560 
561 	pr_debug("bus is %s (na=%d, ns=%d) on %pOF\n",
562 	    bus->name, na, ns, parent);
563 	of_dump_addr("translating address:", addr, na);
564 
565 	/* Translate */
566 	for (;;) {
567 		struct logic_pio_hwaddr *iorange;
568 
569 		/* Switch to parent bus */
570 		of_node_put(dev);
571 		dev = parent;
572 		parent = get_parent(dev);
573 
574 		/* If root, we have finished */
575 		if (parent == NULL) {
576 			pr_debug("reached root node\n");
577 			result = of_read_number(addr, na);
578 			break;
579 		}
580 
581 		/*
582 		 * For indirectIO device which has no ranges property, get
583 		 * the address from reg directly.
584 		 */
585 		iorange = find_io_range_by_fwnode(&dev->fwnode);
586 		if (iorange && (iorange->flags != LOGIC_PIO_CPU_MMIO)) {
587 			result = of_read_number(addr + 1, na - 1);
588 			pr_debug("indirectIO matched(%pOF) 0x%llx\n",
589 				 dev, result);
590 			*host = of_node_get(dev);
591 			break;
592 		}
593 
594 		/* Get new parent bus and counts */
595 		pbus = of_match_bus(parent);
596 		pbus->count_cells(dev, &pna, &pns);
597 		if (!OF_CHECK_COUNTS(pna, pns)) {
598 			pr_err("Bad cell count for %pOF\n", dev);
599 			break;
600 		}
601 
602 		pr_debug("parent bus is %s (na=%d, ns=%d) on %pOF\n",
603 		    pbus->name, pna, pns, parent);
604 
605 		/* Apply bus translation */
606 		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
607 			break;
608 
609 		/* Complete the move up one level */
610 		na = pna;
611 		ns = pns;
612 		bus = pbus;
613 
614 		of_dump_addr("one level translation:", addr, na);
615 	}
616  bail:
617 	of_node_put(parent);
618 	of_node_put(dev);
619 
620 	return result;
621 }
622 
623 u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
624 {
625 	struct device_node *host;
626 	u64 ret;
627 
628 	ret = __of_translate_address(dev, of_get_parent,
629 				     in_addr, "ranges", &host);
630 	if (host) {
631 		of_node_put(host);
632 		return OF_BAD_ADDR;
633 	}
634 
635 	return ret;
636 }
637 EXPORT_SYMBOL(of_translate_address);
638 
639 #ifdef CONFIG_HAS_DMA
640 struct device_node *__of_get_dma_parent(const struct device_node *np)
641 {
642 	struct of_phandle_args args;
643 	int ret, index;
644 
645 	index = of_property_match_string(np, "interconnect-names", "dma-mem");
646 	if (index < 0)
647 		return of_get_parent(np);
648 
649 	ret = of_parse_phandle_with_args(np, "interconnects",
650 					 "#interconnect-cells",
651 					 index, &args);
652 	if (ret < 0)
653 		return of_get_parent(np);
654 
655 	return of_node_get(args.np);
656 }
657 #endif
658 
659 static struct device_node *of_get_next_dma_parent(struct device_node *np)
660 {
661 	struct device_node *parent;
662 
663 	parent = __of_get_dma_parent(np);
664 	of_node_put(np);
665 
666 	return parent;
667 }
668 
669 u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
670 {
671 	struct device_node *host;
672 	u64 ret;
673 
674 	ret = __of_translate_address(dev, __of_get_dma_parent,
675 				     in_addr, "dma-ranges", &host);
676 
677 	if (host) {
678 		of_node_put(host);
679 		return OF_BAD_ADDR;
680 	}
681 
682 	return ret;
683 }
684 EXPORT_SYMBOL(of_translate_dma_address);
685 
686 /**
687  * of_translate_dma_region - Translate device tree address and size tuple
688  * @dev: device tree node for which to translate
689  * @prop: pointer into array of cells
690  * @start: return value for the start of the DMA range
691  * @length: return value for the length of the DMA range
692  *
693  * Returns a pointer to the cell immediately following the translated DMA region.
694  */
695 const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *prop,
696 				      phys_addr_t *start, size_t *length)
697 {
698 	struct device_node *parent;
699 	u64 address, size;
700 	int na, ns;
701 
702 	parent = __of_get_dma_parent(dev);
703 	if (!parent)
704 		return NULL;
705 
706 	na = of_bus_n_addr_cells(parent);
707 	ns = of_bus_n_size_cells(parent);
708 
709 	of_node_put(parent);
710 
711 	address = of_translate_dma_address(dev, prop);
712 	if (address == OF_BAD_ADDR)
713 		return NULL;
714 
715 	size = of_read_number(prop + na, ns);
716 
717 	if (start)
718 		*start = address;
719 
720 	if (length)
721 		*length = size;
722 
723 	return prop + na + ns;
724 }
725 EXPORT_SYMBOL(of_translate_dma_region);
726 
727 const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no,
728 			       u64 *size, unsigned int *flags)
729 {
730 	const __be32 *prop;
731 	unsigned int psize;
732 	struct device_node *parent;
733 	struct of_bus *bus;
734 	int onesize, i, na, ns;
735 
736 	/* Get parent & match bus type */
737 	parent = of_get_parent(dev);
738 	if (parent == NULL)
739 		return NULL;
740 	bus = of_match_bus(parent);
741 	if (strcmp(bus->name, "pci") && (bar_no >= 0)) {
742 		of_node_put(parent);
743 		return NULL;
744 	}
745 	bus->count_cells(dev, &na, &ns);
746 	of_node_put(parent);
747 	if (!OF_CHECK_ADDR_COUNT(na))
748 		return NULL;
749 
750 	/* Get "reg" or "assigned-addresses" property */
751 	prop = of_get_property(dev, bus->addresses, &psize);
752 	if (prop == NULL)
753 		return NULL;
754 	psize /= 4;
755 
756 	onesize = na + ns;
757 	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
758 		u32 val = be32_to_cpu(prop[0]);
759 		/* PCI bus matches on BAR number instead of index */
760 		if (((bar_no >= 0) && ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0))) ||
761 		    ((index >= 0) && (i == index))) {
762 			if (size)
763 				*size = of_read_number(prop + na, ns);
764 			if (flags)
765 				*flags = bus->get_flags(prop);
766 			return prop;
767 		}
768 	}
769 	return NULL;
770 }
771 EXPORT_SYMBOL(__of_get_address);
772 
773 /**
774  * of_property_read_reg - Retrieve the specified "reg" entry index without translating
775  * @np: device tree node for which to retrieve "reg" from
776  * @idx: "reg" entry index to read
777  * @addr: return value for the untranslated address
778  * @size: return value for the entry size
779  *
780  * Returns -EINVAL if "reg" is not found. Returns 0 on success with addr and
781  * size values filled in.
782  */
783 int of_property_read_reg(struct device_node *np, int idx, u64 *addr, u64 *size)
784 {
785 	const __be32 *prop = of_get_address(np, idx, size, NULL);
786 
787 	if (!prop)
788 		return -EINVAL;
789 
790 	*addr = of_read_number(prop, of_n_addr_cells(np));
791 
792 	return 0;
793 }
794 EXPORT_SYMBOL(of_property_read_reg);
795 
796 static int parser_init(struct of_pci_range_parser *parser,
797 			struct device_node *node, const char *name)
798 {
799 	int rlen;
800 
801 	parser->node = node;
802 	parser->pna = of_n_addr_cells(node);
803 	parser->na = of_bus_n_addr_cells(node);
804 	parser->ns = of_bus_n_size_cells(node);
805 	parser->dma = !strcmp(name, "dma-ranges");
806 	parser->bus = of_match_bus(node);
807 
808 	parser->range = of_get_property(node, name, &rlen);
809 	if (parser->range == NULL)
810 		return -ENOENT;
811 
812 	parser->end = parser->range + rlen / sizeof(__be32);
813 
814 	return 0;
815 }
816 
817 int of_pci_range_parser_init(struct of_pci_range_parser *parser,
818 				struct device_node *node)
819 {
820 	return parser_init(parser, node, "ranges");
821 }
822 EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
823 
824 int of_pci_dma_range_parser_init(struct of_pci_range_parser *parser,
825 				struct device_node *node)
826 {
827 	return parser_init(parser, node, "dma-ranges");
828 }
829 EXPORT_SYMBOL_GPL(of_pci_dma_range_parser_init);
830 #define of_dma_range_parser_init of_pci_dma_range_parser_init
831 
832 struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
833 						struct of_pci_range *range)
834 {
835 	int na = parser->na;
836 	int ns = parser->ns;
837 	int np = parser->pna + na + ns;
838 	int busflag_na = 0;
839 
840 	if (!range)
841 		return NULL;
842 
843 	if (!parser->range || parser->range + np > parser->end)
844 		return NULL;
845 
846 	range->flags = parser->bus->get_flags(parser->range);
847 
848 	/* A extra cell for resource flags */
849 	if (parser->bus->has_flags)
850 		busflag_na = 1;
851 
852 	range->bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);
853 
854 	if (parser->dma)
855 		range->cpu_addr = of_translate_dma_address(parser->node,
856 				parser->range + na);
857 	else
858 		range->cpu_addr = of_translate_address(parser->node,
859 				parser->range + na);
860 	range->size = of_read_number(parser->range + parser->pna + na, ns);
861 
862 	parser->range += np;
863 
864 	/* Now consume following elements while they are contiguous */
865 	while (parser->range + np <= parser->end) {
866 		u32 flags = 0;
867 		u64 bus_addr, cpu_addr, size;
868 
869 		flags = parser->bus->get_flags(parser->range);
870 		bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);
871 		if (parser->dma)
872 			cpu_addr = of_translate_dma_address(parser->node,
873 					parser->range + na);
874 		else
875 			cpu_addr = of_translate_address(parser->node,
876 					parser->range + na);
877 		size = of_read_number(parser->range + parser->pna + na, ns);
878 
879 		if (flags != range->flags)
880 			break;
881 		if (bus_addr != range->bus_addr + range->size ||
882 		    cpu_addr != range->cpu_addr + range->size)
883 			break;
884 
885 		range->size += size;
886 		parser->range += np;
887 	}
888 
889 	return range;
890 }
891 EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
892 
893 static u64 of_translate_ioport(struct device_node *dev, const __be32 *in_addr,
894 			u64 size)
895 {
896 	u64 taddr;
897 	unsigned long port;
898 	struct device_node *host;
899 
900 	taddr = __of_translate_address(dev, of_get_parent,
901 				       in_addr, "ranges", &host);
902 	if (host) {
903 		/* host-specific port access */
904 		port = logic_pio_trans_hwaddr(&host->fwnode, taddr, size);
905 		of_node_put(host);
906 	} else {
907 		/* memory-mapped I/O range */
908 		port = pci_address_to_pio(taddr);
909 	}
910 
911 	if (port == (unsigned long)-1)
912 		return OF_BAD_ADDR;
913 
914 	return port;
915 }
916 
917 #ifdef CONFIG_HAS_DMA
918 /**
919  * of_dma_get_range - Get DMA range info and put it into a map array
920  * @np:		device node to get DMA range info
921  * @map:	dma range structure to return
922  *
923  * Look in bottom up direction for the first "dma-ranges" property
924  * and parse it.  Put the information into a DMA offset map array.
925  *
926  * dma-ranges format:
927  *	DMA addr (dma_addr)	: naddr cells
928  *	CPU addr (phys_addr_t)	: pna cells
929  *	size			: nsize cells
930  *
931  * It returns -ENODEV if "dma-ranges" property was not found for this
932  * device in the DT.
933  */
934 int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
935 {
936 	struct device_node *node = of_node_get(np);
937 	const __be32 *ranges = NULL;
938 	bool found_dma_ranges = false;
939 	struct of_range_parser parser;
940 	struct of_range range;
941 	struct bus_dma_region *r;
942 	int len, num_ranges = 0;
943 	int ret = 0;
944 
945 	while (node) {
946 		ranges = of_get_property(node, "dma-ranges", &len);
947 
948 		/* Ignore empty ranges, they imply no translation required */
949 		if (ranges && len > 0)
950 			break;
951 
952 		/* Once we find 'dma-ranges', then a missing one is an error */
953 		if (found_dma_ranges && !ranges) {
954 			ret = -ENODEV;
955 			goto out;
956 		}
957 		found_dma_ranges = true;
958 
959 		node = of_get_next_dma_parent(node);
960 	}
961 
962 	if (!node || !ranges) {
963 		pr_debug("no dma-ranges found for node(%pOF)\n", np);
964 		ret = -ENODEV;
965 		goto out;
966 	}
967 
968 	of_dma_range_parser_init(&parser, node);
969 	for_each_of_range(&parser, &range) {
970 		if (range.cpu_addr == OF_BAD_ADDR) {
971 			pr_err("translation of DMA address(%llx) to CPU address failed node(%pOF)\n",
972 			       range.bus_addr, node);
973 			continue;
974 		}
975 		num_ranges++;
976 	}
977 
978 	if (!num_ranges) {
979 		ret = -EINVAL;
980 		goto out;
981 	}
982 
983 	r = kcalloc(num_ranges + 1, sizeof(*r), GFP_KERNEL);
984 	if (!r) {
985 		ret = -ENOMEM;
986 		goto out;
987 	}
988 
989 	/*
990 	 * Record all info in the generic DMA ranges array for struct device,
991 	 * returning an error if we don't find any parsable ranges.
992 	 */
993 	*map = r;
994 	of_dma_range_parser_init(&parser, node);
995 	for_each_of_range(&parser, &range) {
996 		pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
997 			 range.bus_addr, range.cpu_addr, range.size);
998 		if (range.cpu_addr == OF_BAD_ADDR)
999 			continue;
1000 		r->cpu_start = range.cpu_addr;
1001 		r->dma_start = range.bus_addr;
1002 		r->size = range.size;
1003 		r->offset = range.cpu_addr - range.bus_addr;
1004 		r++;
1005 	}
1006 out:
1007 	of_node_put(node);
1008 	return ret;
1009 }
1010 #endif /* CONFIG_HAS_DMA */
1011 
1012 /**
1013  * of_dma_get_max_cpu_address - Gets highest CPU address suitable for DMA
1014  * @np: The node to start searching from or NULL to start from the root
1015  *
1016  * Gets the highest CPU physical address that is addressable by all DMA masters
1017  * in the sub-tree pointed by np, or the whole tree if NULL is passed. If no
1018  * DMA constrained device is found, it returns PHYS_ADDR_MAX.
1019  */
1020 phys_addr_t __init of_dma_get_max_cpu_address(struct device_node *np)
1021 {
1022 	phys_addr_t max_cpu_addr = PHYS_ADDR_MAX;
1023 	struct of_range_parser parser;
1024 	phys_addr_t subtree_max_addr;
1025 	struct device_node *child;
1026 	struct of_range range;
1027 	const __be32 *ranges;
1028 	u64 cpu_end = 0;
1029 	int len;
1030 
1031 	if (!np)
1032 		np = of_root;
1033 
1034 	ranges = of_get_property(np, "dma-ranges", &len);
1035 	if (ranges && len) {
1036 		of_dma_range_parser_init(&parser, np);
1037 		for_each_of_range(&parser, &range)
1038 			if (range.cpu_addr + range.size > cpu_end)
1039 				cpu_end = range.cpu_addr + range.size - 1;
1040 
1041 		if (max_cpu_addr > cpu_end)
1042 			max_cpu_addr = cpu_end;
1043 	}
1044 
1045 	for_each_available_child_of_node(np, child) {
1046 		subtree_max_addr = of_dma_get_max_cpu_address(child);
1047 		if (max_cpu_addr > subtree_max_addr)
1048 			max_cpu_addr = subtree_max_addr;
1049 	}
1050 
1051 	return max_cpu_addr;
1052 }
1053 
1054 /**
1055  * of_dma_is_coherent - Check if device is coherent
1056  * @np:	device node
1057  *
1058  * It returns true if "dma-coherent" property was found
1059  * for this device in the DT, or if DMA is coherent by
1060  * default for OF devices on the current platform and no
1061  * "dma-noncoherent" property was found for this device.
1062  */
1063 bool of_dma_is_coherent(struct device_node *np)
1064 {
1065 	struct device_node *node;
1066 	bool is_coherent = dma_default_coherent;
1067 
1068 	node = of_node_get(np);
1069 
1070 	while (node) {
1071 		if (of_property_read_bool(node, "dma-coherent")) {
1072 			is_coherent = true;
1073 			break;
1074 		}
1075 		if (of_property_read_bool(node, "dma-noncoherent")) {
1076 			is_coherent = false;
1077 			break;
1078 		}
1079 		node = of_get_next_dma_parent(node);
1080 	}
1081 	of_node_put(node);
1082 	return is_coherent;
1083 }
1084 EXPORT_SYMBOL_GPL(of_dma_is_coherent);
1085 
1086 /**
1087  * of_mmio_is_nonposted - Check if device uses non-posted MMIO
1088  * @np:	device node
1089  *
1090  * Returns true if the "nonposted-mmio" property was found for
1091  * the device's bus.
1092  *
1093  * This is currently only enabled on builds that support Apple ARM devices, as
1094  * an optimization.
1095  */
1096 static bool of_mmio_is_nonposted(struct device_node *np)
1097 {
1098 	struct device_node *parent;
1099 	bool nonposted;
1100 
1101 	if (!IS_ENABLED(CONFIG_ARCH_APPLE))
1102 		return false;
1103 
1104 	parent = of_get_parent(np);
1105 	if (!parent)
1106 		return false;
1107 
1108 	nonposted = of_property_read_bool(parent, "nonposted-mmio");
1109 
1110 	of_node_put(parent);
1111 	return nonposted;
1112 }
1113 
1114 static int __of_address_to_resource(struct device_node *dev, int index, int bar_no,
1115 		struct resource *r)
1116 {
1117 	u64 taddr;
1118 	const __be32	*addrp;
1119 	u64		size;
1120 	unsigned int	flags;
1121 	const char	*name = NULL;
1122 
1123 	addrp = __of_get_address(dev, index, bar_no, &size, &flags);
1124 	if (addrp == NULL)
1125 		return -EINVAL;
1126 
1127 	/* Get optional "reg-names" property to add a name to a resource */
1128 	if (index >= 0)
1129 		of_property_read_string_index(dev, "reg-names",	index, &name);
1130 
1131 	if (flags & IORESOURCE_MEM)
1132 		taddr = of_translate_address(dev, addrp);
1133 	else if (flags & IORESOURCE_IO)
1134 		taddr = of_translate_ioport(dev, addrp, size);
1135 	else
1136 		return -EINVAL;
1137 
1138 	if (taddr == OF_BAD_ADDR)
1139 		return -EINVAL;
1140 	memset(r, 0, sizeof(struct resource));
1141 
1142 	if (of_mmio_is_nonposted(dev))
1143 		flags |= IORESOURCE_MEM_NONPOSTED;
1144 
1145 	r->start = taddr;
1146 	r->end = taddr + size - 1;
1147 	r->flags = flags;
1148 	r->name = name ? name : dev->full_name;
1149 
1150 	return 0;
1151 }
1152 
1153 /**
1154  * of_address_to_resource - Translate device tree address and return as resource
1155  * @dev:	Caller's Device Node
1156  * @index:	Index into the array
1157  * @r:		Pointer to resource array
1158  *
1159  * Returns -EINVAL if the range cannot be converted to resource.
1160  *
1161  * Note that if your address is a PIO address, the conversion will fail if
1162  * the physical address can't be internally converted to an IO token with
1163  * pci_address_to_pio(), that is because it's either called too early or it
1164  * can't be matched to any host bridge IO space
1165  */
1166 int of_address_to_resource(struct device_node *dev, int index,
1167 			   struct resource *r)
1168 {
1169 	return __of_address_to_resource(dev, index, -1, r);
1170 }
1171 EXPORT_SYMBOL_GPL(of_address_to_resource);
1172 
1173 int of_pci_address_to_resource(struct device_node *dev, int bar,
1174 			       struct resource *r)
1175 {
1176 
1177 	if (!IS_ENABLED(CONFIG_PCI))
1178 		return -ENOSYS;
1179 
1180 	return __of_address_to_resource(dev, -1, bar, r);
1181 }
1182 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
1183 
1184 /**
1185  * of_iomap - Maps the memory mapped IO for a given device_node
1186  * @np:		the device whose io range will be mapped
1187  * @index:	index of the io range
1188  *
1189  * Returns a pointer to the mapped memory
1190  */
1191 void __iomem *of_iomap(struct device_node *np, int index)
1192 {
1193 	struct resource res;
1194 
1195 	if (of_address_to_resource(np, index, &res))
1196 		return NULL;
1197 
1198 	if (res.flags & IORESOURCE_MEM_NONPOSTED)
1199 		return ioremap_np(res.start, resource_size(&res));
1200 	else
1201 		return ioremap(res.start, resource_size(&res));
1202 }
1203 EXPORT_SYMBOL(of_iomap);
1204 
1205 /*
1206  * of_io_request_and_map - Requests a resource and maps the memory mapped IO
1207  *			   for a given device_node
1208  * @device:	the device whose io range will be mapped
1209  * @index:	index of the io range
1210  * @name:	name "override" for the memory region request or NULL
1211  *
1212  * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
1213  * error code on failure. Usage example:
1214  *
1215  *	base = of_io_request_and_map(node, 0, "foo");
1216  *	if (IS_ERR(base))
1217  *		return PTR_ERR(base);
1218  */
1219 void __iomem *of_io_request_and_map(struct device_node *np, int index,
1220 				    const char *name)
1221 {
1222 	struct resource res;
1223 	void __iomem *mem;
1224 
1225 	if (of_address_to_resource(np, index, &res))
1226 		return IOMEM_ERR_PTR(-EINVAL);
1227 
1228 	if (!name)
1229 		name = res.name;
1230 	if (!request_mem_region(res.start, resource_size(&res), name))
1231 		return IOMEM_ERR_PTR(-EBUSY);
1232 
1233 	if (res.flags & IORESOURCE_MEM_NONPOSTED)
1234 		mem = ioremap_np(res.start, resource_size(&res));
1235 	else
1236 		mem = ioremap(res.start, resource_size(&res));
1237 
1238 	if (!mem) {
1239 		release_mem_region(res.start, resource_size(&res));
1240 		return IOMEM_ERR_PTR(-ENOMEM);
1241 	}
1242 
1243 	return mem;
1244 }
1245 EXPORT_SYMBOL(of_io_request_and_map);
1246