xref: /openbmc/linux/drivers/of/address.c (revision d3402925)
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 static struct of_bus *of_match_bus(struct device_node *np);
26 static int __of_address_to_resource(struct device_node *dev, int index,
27 		int bar_no, struct resource *r);
28 static bool of_mmio_is_nonposted(struct device_node *np);
29 
30 /* Debug utility */
31 #ifdef DEBUG
32 static void of_dump_addr(const char *s, const __be32 *addr, int na)
33 {
34 	pr_debug("%s", s);
35 	while (na--)
36 		pr_cont(" %08x", be32_to_cpu(*(addr++)));
37 	pr_cont("\n");
38 }
39 #else
40 static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
41 #endif
42 
43 /* Callbacks for bus specific translators */
44 struct of_bus {
45 	const char	*name;
46 	const char	*addresses;
47 	int		(*match)(struct device_node *parent);
48 	void		(*count_cells)(struct device_node *child,
49 				       int *addrc, int *sizec);
50 	u64		(*map)(__be32 *addr, const __be32 *range,
51 				int na, int ns, int pna);
52 	int		(*translate)(__be32 *addr, u64 offset, int na);
53 	bool	has_flags;
54 	unsigned int	(*get_flags)(const __be32 *addr);
55 };
56 
57 /*
58  * Default translator (generic bus)
59  */
60 
61 static void of_bus_default_count_cells(struct device_node *dev,
62 				       int *addrc, int *sizec)
63 {
64 	if (addrc)
65 		*addrc = of_n_addr_cells(dev);
66 	if (sizec)
67 		*sizec = of_n_size_cells(dev);
68 }
69 
70 static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
71 		int na, int ns, int pna)
72 {
73 	u64 cp, s, da;
74 
75 	cp = of_read_number(range, na);
76 	s  = of_read_number(range + na + pna, ns);
77 	da = of_read_number(addr, na);
78 
79 	pr_debug("default map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);
80 
81 	if (da < cp || da >= (cp + s))
82 		return OF_BAD_ADDR;
83 	return da - cp;
84 }
85 
86 static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
87 {
88 	u64 a = of_read_number(addr, na);
89 	memset(addr, 0, na * 4);
90 	a += offset;
91 	if (na > 1)
92 		addr[na - 2] = cpu_to_be32(a >> 32);
93 	addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
94 
95 	return 0;
96 }
97 
98 static unsigned int of_bus_default_get_flags(const __be32 *addr)
99 {
100 	return IORESOURCE_MEM;
101 }
102 
103 #ifdef CONFIG_PCI
104 static unsigned int of_bus_pci_get_flags(const __be32 *addr)
105 {
106 	unsigned int flags = 0;
107 	u32 w = be32_to_cpup(addr);
108 
109 	if (!IS_ENABLED(CONFIG_PCI))
110 		return 0;
111 
112 	switch((w >> 24) & 0x03) {
113 	case 0x01:
114 		flags |= IORESOURCE_IO;
115 		break;
116 	case 0x02: /* 32 bits */
117 		flags |= IORESOURCE_MEM;
118 		break;
119 
120 	case 0x03: /* 64 bits */
121 		flags |= IORESOURCE_MEM | IORESOURCE_MEM_64;
122 		break;
123 	}
124 	if (w & 0x40000000)
125 		flags |= IORESOURCE_PREFETCH;
126 	return flags;
127 }
128 
129 /*
130  * PCI bus specific translator
131  */
132 
133 static bool of_node_is_pcie(struct device_node *np)
134 {
135 	bool is_pcie = of_node_name_eq(np, "pcie");
136 
137 	if (is_pcie)
138 		pr_warn_once("%pOF: Missing device_type\n", np);
139 
140 	return is_pcie;
141 }
142 
143 static int of_bus_pci_match(struct device_node *np)
144 {
145 	/*
146  	 * "pciex" is PCI Express
147 	 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
148 	 * "ht" is hypertransport
149 	 *
150 	 * If none of the device_type match, and that the node name is
151 	 * "pcie", accept the device as PCI (with a warning).
152 	 */
153 	return of_node_is_type(np, "pci") || of_node_is_type(np, "pciex") ||
154 		of_node_is_type(np, "vci") || of_node_is_type(np, "ht") ||
155 		of_node_is_pcie(np);
156 }
157 
158 static void of_bus_pci_count_cells(struct device_node *np,
159 				   int *addrc, int *sizec)
160 {
161 	if (addrc)
162 		*addrc = 3;
163 	if (sizec)
164 		*sizec = 2;
165 }
166 
167 static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
168 		int pna)
169 {
170 	u64 cp, s, da;
171 	unsigned int af, rf;
172 
173 	af = of_bus_pci_get_flags(addr);
174 	rf = of_bus_pci_get_flags(range);
175 
176 	/* Check address type match */
177 	if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
178 		return OF_BAD_ADDR;
179 
180 	/* Read address values, skipping high cell */
181 	cp = of_read_number(range + 1, na - 1);
182 	s  = of_read_number(range + na + pna, ns);
183 	da = of_read_number(addr + 1, na - 1);
184 
185 	pr_debug("PCI map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);
186 
187 	if (da < cp || da >= (cp + s))
188 		return OF_BAD_ADDR;
189 	return da - cp;
190 }
191 
192 static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
193 {
194 	return of_bus_default_translate(addr + 1, offset, na - 1);
195 }
196 #endif /* CONFIG_PCI */
197 
198 int of_pci_address_to_resource(struct device_node *dev, int bar,
199 			       struct resource *r)
200 {
201 
202 	if (!IS_ENABLED(CONFIG_PCI))
203 		return -ENOSYS;
204 
205 	return __of_address_to_resource(dev, -1, bar, r);
206 }
207 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
208 
209 /*
210  * of_pci_range_to_resource - Create a resource from an of_pci_range
211  * @range:	the PCI range that describes the resource
212  * @np:		device node where the range belongs to
213  * @res:	pointer to a valid resource that will be updated to
214  *              reflect the values contained in the range.
215  *
216  * Returns EINVAL if the range cannot be converted to resource.
217  *
218  * Note that if the range is an IO range, the resource will be converted
219  * using pci_address_to_pio() which can fail if it is called too early or
220  * if the range cannot be matched to any host bridge IO space (our case here).
221  * To guard against that we try to register the IO range first.
222  * If that fails we know that pci_address_to_pio() will do too.
223  */
224 int of_pci_range_to_resource(struct of_pci_range *range,
225 			     struct device_node *np, struct resource *res)
226 {
227 	int err;
228 	res->flags = range->flags;
229 	res->parent = res->child = res->sibling = NULL;
230 	res->name = np->full_name;
231 
232 	if (!IS_ENABLED(CONFIG_PCI))
233 		return -ENOSYS;
234 
235 	if (res->flags & IORESOURCE_IO) {
236 		unsigned long port;
237 		err = pci_register_io_range(&np->fwnode, range->cpu_addr,
238 				range->size);
239 		if (err)
240 			goto invalid_range;
241 		port = pci_address_to_pio(range->cpu_addr);
242 		if (port == (unsigned long)-1) {
243 			err = -EINVAL;
244 			goto invalid_range;
245 		}
246 		res->start = port;
247 	} else {
248 		if ((sizeof(resource_size_t) < 8) &&
249 		    upper_32_bits(range->cpu_addr)) {
250 			err = -EINVAL;
251 			goto invalid_range;
252 		}
253 
254 		res->start = range->cpu_addr;
255 	}
256 	res->end = res->start + range->size - 1;
257 	return 0;
258 
259 invalid_range:
260 	res->start = (resource_size_t)OF_BAD_ADDR;
261 	res->end = (resource_size_t)OF_BAD_ADDR;
262 	return err;
263 }
264 EXPORT_SYMBOL(of_pci_range_to_resource);
265 
266 /*
267  * ISA bus specific translator
268  */
269 
270 static int of_bus_isa_match(struct device_node *np)
271 {
272 	return of_node_name_eq(np, "isa");
273 }
274 
275 static void of_bus_isa_count_cells(struct device_node *child,
276 				   int *addrc, int *sizec)
277 {
278 	if (addrc)
279 		*addrc = 2;
280 	if (sizec)
281 		*sizec = 1;
282 }
283 
284 static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
285 		int pna)
286 {
287 	u64 cp, s, da;
288 
289 	/* Check address type match */
290 	if ((addr[0] ^ range[0]) & cpu_to_be32(1))
291 		return OF_BAD_ADDR;
292 
293 	/* Read address values, skipping high cell */
294 	cp = of_read_number(range + 1, na - 1);
295 	s  = of_read_number(range + na + pna, ns);
296 	da = of_read_number(addr + 1, na - 1);
297 
298 	pr_debug("ISA map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);
299 
300 	if (da < cp || da >= (cp + s))
301 		return OF_BAD_ADDR;
302 	return da - cp;
303 }
304 
305 static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
306 {
307 	return of_bus_default_translate(addr + 1, offset, na - 1);
308 }
309 
310 static unsigned int of_bus_isa_get_flags(const __be32 *addr)
311 {
312 	unsigned int flags = 0;
313 	u32 w = be32_to_cpup(addr);
314 
315 	if (w & 1)
316 		flags |= IORESOURCE_IO;
317 	else
318 		flags |= IORESOURCE_MEM;
319 	return flags;
320 }
321 
322 /*
323  * Array of bus specific translators
324  */
325 
326 static struct of_bus of_busses[] = {
327 #ifdef CONFIG_PCI
328 	/* PCI */
329 	{
330 		.name = "pci",
331 		.addresses = "assigned-addresses",
332 		.match = of_bus_pci_match,
333 		.count_cells = of_bus_pci_count_cells,
334 		.map = of_bus_pci_map,
335 		.translate = of_bus_pci_translate,
336 		.has_flags = true,
337 		.get_flags = of_bus_pci_get_flags,
338 	},
339 #endif /* CONFIG_PCI */
340 	/* ISA */
341 	{
342 		.name = "isa",
343 		.addresses = "reg",
344 		.match = of_bus_isa_match,
345 		.count_cells = of_bus_isa_count_cells,
346 		.map = of_bus_isa_map,
347 		.translate = of_bus_isa_translate,
348 		.has_flags = true,
349 		.get_flags = of_bus_isa_get_flags,
350 	},
351 	/* Default */
352 	{
353 		.name = "default",
354 		.addresses = "reg",
355 		.match = NULL,
356 		.count_cells = of_bus_default_count_cells,
357 		.map = of_bus_default_map,
358 		.translate = of_bus_default_translate,
359 		.get_flags = of_bus_default_get_flags,
360 	},
361 };
362 
363 static struct of_bus *of_match_bus(struct device_node *np)
364 {
365 	int i;
366 
367 	for (i = 0; i < ARRAY_SIZE(of_busses); i++)
368 		if (!of_busses[i].match || of_busses[i].match(np))
369 			return &of_busses[i];
370 	BUG();
371 	return NULL;
372 }
373 
374 static int of_empty_ranges_quirk(struct device_node *np)
375 {
376 	if (IS_ENABLED(CONFIG_PPC)) {
377 		/* To save cycles, we cache the result for global "Mac" setting */
378 		static int quirk_state = -1;
379 
380 		/* PA-SEMI sdc DT bug */
381 		if (of_device_is_compatible(np, "1682m-sdc"))
382 			return true;
383 
384 		/* Make quirk cached */
385 		if (quirk_state < 0)
386 			quirk_state =
387 				of_machine_is_compatible("Power Macintosh") ||
388 				of_machine_is_compatible("MacRISC");
389 		return quirk_state;
390 	}
391 	return false;
392 }
393 
394 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
395 			    struct of_bus *pbus, __be32 *addr,
396 			    int na, int ns, int pna, const char *rprop)
397 {
398 	const __be32 *ranges;
399 	unsigned int rlen;
400 	int rone;
401 	u64 offset = OF_BAD_ADDR;
402 
403 	/*
404 	 * Normally, an absence of a "ranges" property means we are
405 	 * crossing a non-translatable boundary, and thus the addresses
406 	 * below the current cannot be converted to CPU physical ones.
407 	 * Unfortunately, while this is very clear in the spec, it's not
408 	 * what Apple understood, and they do have things like /uni-n or
409 	 * /ht nodes with no "ranges" property and a lot of perfectly
410 	 * useable mapped devices below them. Thus we treat the absence of
411 	 * "ranges" as equivalent to an empty "ranges" property which means
412 	 * a 1:1 translation at that level. It's up to the caller not to try
413 	 * to translate addresses that aren't supposed to be translated in
414 	 * the first place. --BenH.
415 	 *
416 	 * As far as we know, this damage only exists on Apple machines, so
417 	 * This code is only enabled on powerpc. --gcl
418 	 *
419 	 * This quirk also applies for 'dma-ranges' which frequently exist in
420 	 * child nodes without 'dma-ranges' in the parent nodes. --RobH
421 	 */
422 	ranges = of_get_property(parent, rprop, &rlen);
423 	if (ranges == NULL && !of_empty_ranges_quirk(parent) &&
424 	    strcmp(rprop, "dma-ranges")) {
425 		pr_debug("no ranges; cannot translate\n");
426 		return 1;
427 	}
428 	if (ranges == NULL || rlen == 0) {
429 		offset = of_read_number(addr, na);
430 		memset(addr, 0, pna * 4);
431 		pr_debug("empty ranges; 1:1 translation\n");
432 		goto finish;
433 	}
434 
435 	pr_debug("walking ranges...\n");
436 
437 	/* Now walk through the ranges */
438 	rlen /= 4;
439 	rone = na + pna + ns;
440 	for (; rlen >= rone; rlen -= rone, ranges += rone) {
441 		offset = bus->map(addr, ranges, na, ns, pna);
442 		if (offset != OF_BAD_ADDR)
443 			break;
444 	}
445 	if (offset == OF_BAD_ADDR) {
446 		pr_debug("not found !\n");
447 		return 1;
448 	}
449 	memcpy(addr, ranges + na, 4 * pna);
450 
451  finish:
452 	of_dump_addr("parent translation for:", addr, pna);
453 	pr_debug("with offset: %llx\n", offset);
454 
455 	/* Translate it into parent bus space */
456 	return pbus->translate(addr, offset, pna);
457 }
458 
459 /*
460  * Translate an address from the device-tree into a CPU physical address,
461  * this walks up the tree and applies the various bus mappings on the
462  * way.
463  *
464  * Note: We consider that crossing any level with #size-cells == 0 to mean
465  * that translation is impossible (that is we are not dealing with a value
466  * that can be mapped to a cpu physical address). This is not really specified
467  * that way, but this is traditionally the way IBM at least do things
468  *
469  * Whenever the translation fails, the *host pointer will be set to the
470  * device that had registered logical PIO mapping, and the return code is
471  * relative to that node.
472  */
473 static u64 __of_translate_address(struct device_node *dev,
474 				  struct device_node *(*get_parent)(const struct device_node *),
475 				  const __be32 *in_addr, const char *rprop,
476 				  struct device_node **host)
477 {
478 	struct device_node *parent = NULL;
479 	struct of_bus *bus, *pbus;
480 	__be32 addr[OF_MAX_ADDR_CELLS];
481 	int na, ns, pna, pns;
482 	u64 result = OF_BAD_ADDR;
483 
484 	pr_debug("** translation for device %pOF **\n", dev);
485 
486 	/* Increase refcount at current level */
487 	of_node_get(dev);
488 
489 	*host = NULL;
490 	/* Get parent & match bus type */
491 	parent = get_parent(dev);
492 	if (parent == NULL)
493 		goto bail;
494 	bus = of_match_bus(parent);
495 
496 	/* Count address cells & copy address locally */
497 	bus->count_cells(dev, &na, &ns);
498 	if (!OF_CHECK_COUNTS(na, ns)) {
499 		pr_debug("Bad cell count for %pOF\n", dev);
500 		goto bail;
501 	}
502 	memcpy(addr, in_addr, na * 4);
503 
504 	pr_debug("bus is %s (na=%d, ns=%d) on %pOF\n",
505 	    bus->name, na, ns, parent);
506 	of_dump_addr("translating address:", addr, na);
507 
508 	/* Translate */
509 	for (;;) {
510 		struct logic_pio_hwaddr *iorange;
511 
512 		/* Switch to parent bus */
513 		of_node_put(dev);
514 		dev = parent;
515 		parent = get_parent(dev);
516 
517 		/* If root, we have finished */
518 		if (parent == NULL) {
519 			pr_debug("reached root node\n");
520 			result = of_read_number(addr, na);
521 			break;
522 		}
523 
524 		/*
525 		 * For indirectIO device which has no ranges property, get
526 		 * the address from reg directly.
527 		 */
528 		iorange = find_io_range_by_fwnode(&dev->fwnode);
529 		if (iorange && (iorange->flags != LOGIC_PIO_CPU_MMIO)) {
530 			result = of_read_number(addr + 1, na - 1);
531 			pr_debug("indirectIO matched(%pOF) 0x%llx\n",
532 				 dev, result);
533 			*host = of_node_get(dev);
534 			break;
535 		}
536 
537 		/* Get new parent bus and counts */
538 		pbus = of_match_bus(parent);
539 		pbus->count_cells(dev, &pna, &pns);
540 		if (!OF_CHECK_COUNTS(pna, pns)) {
541 			pr_err("Bad cell count for %pOF\n", dev);
542 			break;
543 		}
544 
545 		pr_debug("parent bus is %s (na=%d, ns=%d) on %pOF\n",
546 		    pbus->name, pna, pns, parent);
547 
548 		/* Apply bus translation */
549 		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
550 			break;
551 
552 		/* Complete the move up one level */
553 		na = pna;
554 		ns = pns;
555 		bus = pbus;
556 
557 		of_dump_addr("one level translation:", addr, na);
558 	}
559  bail:
560 	of_node_put(parent);
561 	of_node_put(dev);
562 
563 	return result;
564 }
565 
566 u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
567 {
568 	struct device_node *host;
569 	u64 ret;
570 
571 	ret = __of_translate_address(dev, of_get_parent,
572 				     in_addr, "ranges", &host);
573 	if (host) {
574 		of_node_put(host);
575 		return OF_BAD_ADDR;
576 	}
577 
578 	return ret;
579 }
580 EXPORT_SYMBOL(of_translate_address);
581 
582 #ifdef CONFIG_HAS_DMA
583 struct device_node *__of_get_dma_parent(const struct device_node *np)
584 {
585 	struct of_phandle_args args;
586 	int ret, index;
587 
588 	index = of_property_match_string(np, "interconnect-names", "dma-mem");
589 	if (index < 0)
590 		return of_get_parent(np);
591 
592 	ret = of_parse_phandle_with_args(np, "interconnects",
593 					 "#interconnect-cells",
594 					 index, &args);
595 	if (ret < 0)
596 		return of_get_parent(np);
597 
598 	return of_node_get(args.np);
599 }
600 #endif
601 
602 static struct device_node *of_get_next_dma_parent(struct device_node *np)
603 {
604 	struct device_node *parent;
605 
606 	parent = __of_get_dma_parent(np);
607 	of_node_put(np);
608 
609 	return parent;
610 }
611 
612 u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
613 {
614 	struct device_node *host;
615 	u64 ret;
616 
617 	ret = __of_translate_address(dev, __of_get_dma_parent,
618 				     in_addr, "dma-ranges", &host);
619 
620 	if (host) {
621 		of_node_put(host);
622 		return OF_BAD_ADDR;
623 	}
624 
625 	return ret;
626 }
627 EXPORT_SYMBOL(of_translate_dma_address);
628 
629 /**
630  * of_translate_dma_region - Translate device tree address and size tuple
631  * @dev: device tree node for which to translate
632  * @prop: pointer into array of cells
633  * @start: return value for the start of the DMA range
634  * @length: return value for the length of the DMA range
635  *
636  * Returns a pointer to the cell immediately following the translated DMA region.
637  */
638 const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *prop,
639 				      phys_addr_t *start, size_t *length)
640 {
641 	struct device_node *parent;
642 	u64 address, size;
643 	int na, ns;
644 
645 	parent = __of_get_dma_parent(dev);
646 	if (!parent)
647 		return NULL;
648 
649 	na = of_bus_n_addr_cells(parent);
650 	ns = of_bus_n_size_cells(parent);
651 
652 	of_node_put(parent);
653 
654 	address = of_translate_dma_address(dev, prop);
655 	if (address == OF_BAD_ADDR)
656 		return NULL;
657 
658 	size = of_read_number(prop + na, ns);
659 
660 	if (start)
661 		*start = address;
662 
663 	if (length)
664 		*length = size;
665 
666 	return prop + na + ns;
667 }
668 EXPORT_SYMBOL(of_translate_dma_region);
669 
670 const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no,
671 			       u64 *size, unsigned int *flags)
672 {
673 	const __be32 *prop;
674 	unsigned int psize;
675 	struct device_node *parent;
676 	struct of_bus *bus;
677 	int onesize, i, na, ns;
678 
679 	/* Get parent & match bus type */
680 	parent = of_get_parent(dev);
681 	if (parent == NULL)
682 		return NULL;
683 	bus = of_match_bus(parent);
684 	if (strcmp(bus->name, "pci") && (bar_no >= 0)) {
685 		of_node_put(parent);
686 		return NULL;
687 	}
688 	bus->count_cells(dev, &na, &ns);
689 	of_node_put(parent);
690 	if (!OF_CHECK_ADDR_COUNT(na))
691 		return NULL;
692 
693 	/* Get "reg" or "assigned-addresses" property */
694 	prop = of_get_property(dev, bus->addresses, &psize);
695 	if (prop == NULL)
696 		return NULL;
697 	psize /= 4;
698 
699 	onesize = na + ns;
700 	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
701 		u32 val = be32_to_cpu(prop[0]);
702 		/* PCI bus matches on BAR number instead of index */
703 		if (((bar_no >= 0) && ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0))) ||
704 		    ((index >= 0) && (i == index))) {
705 			if (size)
706 				*size = of_read_number(prop + na, ns);
707 			if (flags)
708 				*flags = bus->get_flags(prop);
709 			return prop;
710 		}
711 	}
712 	return NULL;
713 }
714 EXPORT_SYMBOL(__of_get_address);
715 
716 static int parser_init(struct of_pci_range_parser *parser,
717 			struct device_node *node, const char *name)
718 {
719 	int rlen;
720 
721 	parser->node = node;
722 	parser->pna = of_n_addr_cells(node);
723 	parser->na = of_bus_n_addr_cells(node);
724 	parser->ns = of_bus_n_size_cells(node);
725 	parser->dma = !strcmp(name, "dma-ranges");
726 	parser->bus = of_match_bus(node);
727 
728 	parser->range = of_get_property(node, name, &rlen);
729 	if (parser->range == NULL)
730 		return -ENOENT;
731 
732 	parser->end = parser->range + rlen / sizeof(__be32);
733 
734 	return 0;
735 }
736 
737 int of_pci_range_parser_init(struct of_pci_range_parser *parser,
738 				struct device_node *node)
739 {
740 	return parser_init(parser, node, "ranges");
741 }
742 EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
743 
744 int of_pci_dma_range_parser_init(struct of_pci_range_parser *parser,
745 				struct device_node *node)
746 {
747 	return parser_init(parser, node, "dma-ranges");
748 }
749 EXPORT_SYMBOL_GPL(of_pci_dma_range_parser_init);
750 #define of_dma_range_parser_init of_pci_dma_range_parser_init
751 
752 struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
753 						struct of_pci_range *range)
754 {
755 	int na = parser->na;
756 	int ns = parser->ns;
757 	int np = parser->pna + na + ns;
758 	int busflag_na = 0;
759 
760 	if (!range)
761 		return NULL;
762 
763 	if (!parser->range || parser->range + np > parser->end)
764 		return NULL;
765 
766 	range->flags = parser->bus->get_flags(parser->range);
767 
768 	/* A extra cell for resource flags */
769 	if (parser->bus->has_flags)
770 		busflag_na = 1;
771 
772 	range->bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);
773 
774 	if (parser->dma)
775 		range->cpu_addr = of_translate_dma_address(parser->node,
776 				parser->range + na);
777 	else
778 		range->cpu_addr = of_translate_address(parser->node,
779 				parser->range + na);
780 	range->size = of_read_number(parser->range + parser->pna + na, ns);
781 
782 	parser->range += np;
783 
784 	/* Now consume following elements while they are contiguous */
785 	while (parser->range + np <= parser->end) {
786 		u32 flags = 0;
787 		u64 bus_addr, cpu_addr, size;
788 
789 		flags = parser->bus->get_flags(parser->range);
790 		bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);
791 		if (parser->dma)
792 			cpu_addr = of_translate_dma_address(parser->node,
793 					parser->range + na);
794 		else
795 			cpu_addr = of_translate_address(parser->node,
796 					parser->range + na);
797 		size = of_read_number(parser->range + parser->pna + na, ns);
798 
799 		if (flags != range->flags)
800 			break;
801 		if (bus_addr != range->bus_addr + range->size ||
802 		    cpu_addr != range->cpu_addr + range->size)
803 			break;
804 
805 		range->size += size;
806 		parser->range += np;
807 	}
808 
809 	return range;
810 }
811 EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
812 
813 static u64 of_translate_ioport(struct device_node *dev, const __be32 *in_addr,
814 			u64 size)
815 {
816 	u64 taddr;
817 	unsigned long port;
818 	struct device_node *host;
819 
820 	taddr = __of_translate_address(dev, of_get_parent,
821 				       in_addr, "ranges", &host);
822 	if (host) {
823 		/* host-specific port access */
824 		port = logic_pio_trans_hwaddr(&host->fwnode, taddr, size);
825 		of_node_put(host);
826 	} else {
827 		/* memory-mapped I/O range */
828 		port = pci_address_to_pio(taddr);
829 	}
830 
831 	if (port == (unsigned long)-1)
832 		return OF_BAD_ADDR;
833 
834 	return port;
835 }
836 
837 static int __of_address_to_resource(struct device_node *dev, int index, int bar_no,
838 		struct resource *r)
839 {
840 	u64 taddr;
841 	const __be32	*addrp;
842 	u64		size;
843 	unsigned int	flags;
844 	const char	*name = NULL;
845 
846 	addrp = __of_get_address(dev, index, bar_no, &size, &flags);
847 	if (addrp == NULL)
848 		return -EINVAL;
849 
850 	/* Get optional "reg-names" property to add a name to a resource */
851 	if (index >= 0)
852 		of_property_read_string_index(dev, "reg-names",	index, &name);
853 
854 	if (flags & IORESOURCE_MEM)
855 		taddr = of_translate_address(dev, addrp);
856 	else if (flags & IORESOURCE_IO)
857 		taddr = of_translate_ioport(dev, addrp, size);
858 	else
859 		return -EINVAL;
860 
861 	if (taddr == OF_BAD_ADDR)
862 		return -EINVAL;
863 	memset(r, 0, sizeof(struct resource));
864 
865 	if (of_mmio_is_nonposted(dev))
866 		flags |= IORESOURCE_MEM_NONPOSTED;
867 
868 	r->start = taddr;
869 	r->end = taddr + size - 1;
870 	r->flags = flags;
871 	r->name = name ? name : dev->full_name;
872 
873 	return 0;
874 }
875 
876 /**
877  * of_address_to_resource - Translate device tree address and return as resource
878  * @dev:	Caller's Device Node
879  * @index:	Index into the array
880  * @r:		Pointer to resource array
881  *
882  * Note that if your address is a PIO address, the conversion will fail if
883  * the physical address can't be internally converted to an IO token with
884  * pci_address_to_pio(), that is because it's either called too early or it
885  * can't be matched to any host bridge IO space
886  */
887 int of_address_to_resource(struct device_node *dev, int index,
888 			   struct resource *r)
889 {
890 	return __of_address_to_resource(dev, index, -1, r);
891 }
892 EXPORT_SYMBOL_GPL(of_address_to_resource);
893 
894 /**
895  * of_iomap - Maps the memory mapped IO for a given device_node
896  * @np:		the device whose io range will be mapped
897  * @index:	index of the io range
898  *
899  * Returns a pointer to the mapped memory
900  */
901 void __iomem *of_iomap(struct device_node *np, int index)
902 {
903 	struct resource res;
904 
905 	if (of_address_to_resource(np, index, &res))
906 		return NULL;
907 
908 	if (res.flags & IORESOURCE_MEM_NONPOSTED)
909 		return ioremap_np(res.start, resource_size(&res));
910 	else
911 		return ioremap(res.start, resource_size(&res));
912 }
913 EXPORT_SYMBOL(of_iomap);
914 
915 /*
916  * of_io_request_and_map - Requests a resource and maps the memory mapped IO
917  *			   for a given device_node
918  * @device:	the device whose io range will be mapped
919  * @index:	index of the io range
920  * @name:	name "override" for the memory region request or NULL
921  *
922  * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
923  * error code on failure. Usage example:
924  *
925  *	base = of_io_request_and_map(node, 0, "foo");
926  *	if (IS_ERR(base))
927  *		return PTR_ERR(base);
928  */
929 void __iomem *of_io_request_and_map(struct device_node *np, int index,
930 				    const char *name)
931 {
932 	struct resource res;
933 	void __iomem *mem;
934 
935 	if (of_address_to_resource(np, index, &res))
936 		return IOMEM_ERR_PTR(-EINVAL);
937 
938 	if (!name)
939 		name = res.name;
940 	if (!request_mem_region(res.start, resource_size(&res), name))
941 		return IOMEM_ERR_PTR(-EBUSY);
942 
943 	if (res.flags & IORESOURCE_MEM_NONPOSTED)
944 		mem = ioremap_np(res.start, resource_size(&res));
945 	else
946 		mem = ioremap(res.start, resource_size(&res));
947 
948 	if (!mem) {
949 		release_mem_region(res.start, resource_size(&res));
950 		return IOMEM_ERR_PTR(-ENOMEM);
951 	}
952 
953 	return mem;
954 }
955 EXPORT_SYMBOL(of_io_request_and_map);
956 
957 #ifdef CONFIG_HAS_DMA
958 /**
959  * of_dma_get_range - Get DMA range info and put it into a map array
960  * @np:		device node to get DMA range info
961  * @map:	dma range structure to return
962  *
963  * Look in bottom up direction for the first "dma-ranges" property
964  * and parse it.  Put the information into a DMA offset map array.
965  *
966  * dma-ranges format:
967  *	DMA addr (dma_addr)	: naddr cells
968  *	CPU addr (phys_addr_t)	: pna cells
969  *	size			: nsize cells
970  *
971  * It returns -ENODEV if "dma-ranges" property was not found for this
972  * device in the DT.
973  */
974 int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
975 {
976 	struct device_node *node = of_node_get(np);
977 	const __be32 *ranges = NULL;
978 	bool found_dma_ranges = false;
979 	struct of_range_parser parser;
980 	struct of_range range;
981 	struct bus_dma_region *r;
982 	int len, num_ranges = 0;
983 	int ret = 0;
984 
985 	while (node) {
986 		ranges = of_get_property(node, "dma-ranges", &len);
987 
988 		/* Ignore empty ranges, they imply no translation required */
989 		if (ranges && len > 0)
990 			break;
991 
992 		/* Once we find 'dma-ranges', then a missing one is an error */
993 		if (found_dma_ranges && !ranges) {
994 			ret = -ENODEV;
995 			goto out;
996 		}
997 		found_dma_ranges = true;
998 
999 		node = of_get_next_dma_parent(node);
1000 	}
1001 
1002 	if (!node || !ranges) {
1003 		pr_debug("no dma-ranges found for node(%pOF)\n", np);
1004 		ret = -ENODEV;
1005 		goto out;
1006 	}
1007 
1008 	of_dma_range_parser_init(&parser, node);
1009 	for_each_of_range(&parser, &range) {
1010 		if (range.cpu_addr == OF_BAD_ADDR) {
1011 			pr_err("translation of DMA address(%llx) to CPU address failed node(%pOF)\n",
1012 			       range.bus_addr, node);
1013 			continue;
1014 		}
1015 		num_ranges++;
1016 	}
1017 
1018 	if (!num_ranges) {
1019 		ret = -EINVAL;
1020 		goto out;
1021 	}
1022 
1023 	r = kcalloc(num_ranges + 1, sizeof(*r), GFP_KERNEL);
1024 	if (!r) {
1025 		ret = -ENOMEM;
1026 		goto out;
1027 	}
1028 
1029 	/*
1030 	 * Record all info in the generic DMA ranges array for struct device,
1031 	 * returning an error if we don't find any parsable ranges.
1032 	 */
1033 	*map = r;
1034 	of_dma_range_parser_init(&parser, node);
1035 	for_each_of_range(&parser, &range) {
1036 		pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
1037 			 range.bus_addr, range.cpu_addr, range.size);
1038 		if (range.cpu_addr == OF_BAD_ADDR)
1039 			continue;
1040 		r->cpu_start = range.cpu_addr;
1041 		r->dma_start = range.bus_addr;
1042 		r->size = range.size;
1043 		r->offset = range.cpu_addr - range.bus_addr;
1044 		r++;
1045 	}
1046 out:
1047 	of_node_put(node);
1048 	return ret;
1049 }
1050 #endif /* CONFIG_HAS_DMA */
1051 
1052 /**
1053  * of_dma_get_max_cpu_address - Gets highest CPU address suitable for DMA
1054  * @np: The node to start searching from or NULL to start from the root
1055  *
1056  * Gets the highest CPU physical address that is addressable by all DMA masters
1057  * in the sub-tree pointed by np, or the whole tree if NULL is passed. If no
1058  * DMA constrained device is found, it returns PHYS_ADDR_MAX.
1059  */
1060 phys_addr_t __init of_dma_get_max_cpu_address(struct device_node *np)
1061 {
1062 	phys_addr_t max_cpu_addr = PHYS_ADDR_MAX;
1063 	struct of_range_parser parser;
1064 	phys_addr_t subtree_max_addr;
1065 	struct device_node *child;
1066 	struct of_range range;
1067 	const __be32 *ranges;
1068 	u64 cpu_end = 0;
1069 	int len;
1070 
1071 	if (!np)
1072 		np = of_root;
1073 
1074 	ranges = of_get_property(np, "dma-ranges", &len);
1075 	if (ranges && len) {
1076 		of_dma_range_parser_init(&parser, np);
1077 		for_each_of_range(&parser, &range)
1078 			if (range.cpu_addr + range.size > cpu_end)
1079 				cpu_end = range.cpu_addr + range.size - 1;
1080 
1081 		if (max_cpu_addr > cpu_end)
1082 			max_cpu_addr = cpu_end;
1083 	}
1084 
1085 	for_each_available_child_of_node(np, child) {
1086 		subtree_max_addr = of_dma_get_max_cpu_address(child);
1087 		if (max_cpu_addr > subtree_max_addr)
1088 			max_cpu_addr = subtree_max_addr;
1089 	}
1090 
1091 	return max_cpu_addr;
1092 }
1093 
1094 /**
1095  * of_dma_is_coherent - Check if device is coherent
1096  * @np:	device node
1097  *
1098  * It returns true if "dma-coherent" property was found
1099  * for this device in the DT, or if DMA is coherent by
1100  * default for OF devices on the current platform and no
1101  * "dma-noncoherent" property was found for this device.
1102  */
1103 bool of_dma_is_coherent(struct device_node *np)
1104 {
1105 	struct device_node *node;
1106 	bool is_coherent = IS_ENABLED(CONFIG_OF_DMA_DEFAULT_COHERENT);
1107 
1108 	node = of_node_get(np);
1109 
1110 	while (node) {
1111 		if (of_property_read_bool(node, "dma-coherent")) {
1112 			is_coherent = true;
1113 			break;
1114 		}
1115 		if (of_property_read_bool(node, "dma-noncoherent")) {
1116 			is_coherent = false;
1117 			break;
1118 		}
1119 		node = of_get_next_dma_parent(node);
1120 	}
1121 	of_node_put(node);
1122 	return is_coherent;
1123 }
1124 EXPORT_SYMBOL_GPL(of_dma_is_coherent);
1125 
1126 /**
1127  * of_mmio_is_nonposted - Check if device uses non-posted MMIO
1128  * @np:	device node
1129  *
1130  * Returns true if the "nonposted-mmio" property was found for
1131  * the device's bus.
1132  *
1133  * This is currently only enabled on builds that support Apple ARM devices, as
1134  * an optimization.
1135  */
1136 static bool of_mmio_is_nonposted(struct device_node *np)
1137 {
1138 	struct device_node *parent;
1139 	bool nonposted;
1140 
1141 	if (!IS_ENABLED(CONFIG_ARCH_APPLE))
1142 		return false;
1143 
1144 	parent = of_get_parent(np);
1145 	if (!parent)
1146 		return false;
1147 
1148 	nonposted = of_property_read_bool(parent, "nonposted-mmio");
1149 
1150 	of_node_put(parent);
1151 	return nonposted;
1152 }
1153