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v3.5.6
 
 
  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_COUNTS(na, ns)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS && \
 13			(ns) > 0)
 14
 15static struct of_bus *of_match_bus(struct device_node *np);
 16static 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
 22static 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
 30static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
 31#endif
 32
 33/* Callbacks for bus specific translators */
 34struct 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)(u32 *addr, const __be32 *range,
 41				int na, int ns, int pna);
 42	int		(*translate)(u32 *addr, u64 offset, int na);
 43	unsigned int	(*get_flags)(const __be32 *addr);
 44};
 45
 46/*
 47 * Default translator (generic bus)
 48 */
 49
 50static 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
 59static u64 of_bus_default_map(u32 *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
 77static int of_bus_default_translate(u32 *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
 89static unsigned int of_bus_default_get_flags(const __be32 *addr)
 90{
 91	return IORESOURCE_MEM;
 92}
 93
 94#ifdef CONFIG_PCI
 95/*
 96 * PCI bus specific translator
 97 */
 98
 99static int of_bus_pci_match(struct device_node *np)
100{
101	/* "vci" is for the /chaos bridge on 1st-gen PCI powermacs */
102	return !strcmp(np->type, "pci") || !strcmp(np->type, "vci");
 
 
 
 
 
103}
104
105static void of_bus_pci_count_cells(struct device_node *np,
106				   int *addrc, int *sizec)
107{
108	if (addrc)
109		*addrc = 3;
110	if (sizec)
111		*sizec = 2;
112}
113
114static unsigned int of_bus_pci_get_flags(const __be32 *addr)
115{
116	unsigned int flags = 0;
117	u32 w = be32_to_cpup(addr);
118
119	switch((w >> 24) & 0x03) {
120	case 0x01:
121		flags |= IORESOURCE_IO;
122		break;
123	case 0x02: /* 32 bits */
124	case 0x03: /* 64 bits */
125		flags |= IORESOURCE_MEM;
126		break;
127	}
128	if (w & 0x40000000)
129		flags |= IORESOURCE_PREFETCH;
130	return flags;
131}
132
133static u64 of_bus_pci_map(u32 *addr, const __be32 *range, int na, int ns,
134		int pna)
135{
136	u64 cp, s, da;
137	unsigned int af, rf;
138
139	af = of_bus_pci_get_flags(addr);
140	rf = of_bus_pci_get_flags(range);
141
142	/* Check address type match */
143	if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
144		return OF_BAD_ADDR;
145
146	/* Read address values, skipping high cell */
147	cp = of_read_number(range + 1, na - 1);
148	s  = of_read_number(range + na + pna, ns);
149	da = of_read_number(addr + 1, na - 1);
150
151	pr_debug("OF: PCI map, cp=%llx, s=%llx, da=%llx\n",
152		 (unsigned long long)cp, (unsigned long long)s,
153		 (unsigned long long)da);
154
155	if (da < cp || da >= (cp + s))
156		return OF_BAD_ADDR;
157	return da - cp;
158}
159
160static int of_bus_pci_translate(u32 *addr, u64 offset, int na)
161{
162	return of_bus_default_translate(addr + 1, offset, na - 1);
163}
164
165const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
166			unsigned int *flags)
167{
168	const __be32 *prop;
169	unsigned int psize;
170	struct device_node *parent;
171	struct of_bus *bus;
172	int onesize, i, na, ns;
173
174	/* Get parent & match bus type */
175	parent = of_get_parent(dev);
176	if (parent == NULL)
177		return NULL;
178	bus = of_match_bus(parent);
179	if (strcmp(bus->name, "pci")) {
180		of_node_put(parent);
181		return NULL;
182	}
183	bus->count_cells(dev, &na, &ns);
184	of_node_put(parent);
185	if (!OF_CHECK_COUNTS(na, ns))
186		return NULL;
187
188	/* Get "reg" or "assigned-addresses" property */
189	prop = of_get_property(dev, bus->addresses, &psize);
190	if (prop == NULL)
191		return NULL;
192	psize /= 4;
193
194	onesize = na + ns;
195	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
196		u32 val = be32_to_cpu(prop[0]);
197		if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
198			if (size)
199				*size = of_read_number(prop + na, ns);
200			if (flags)
201				*flags = bus->get_flags(prop);
202			return prop;
203		}
204	}
205	return NULL;
206}
207EXPORT_SYMBOL(of_get_pci_address);
208
209int of_pci_address_to_resource(struct device_node *dev, int bar,
210			       struct resource *r)
211{
212	const __be32	*addrp;
213	u64		size;
214	unsigned int	flags;
215
216	addrp = of_get_pci_address(dev, bar, &size, &flags);
217	if (addrp == NULL)
218		return -EINVAL;
219	return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
220}
221EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
222#endif /* CONFIG_PCI */
223
224/*
225 * ISA bus specific translator
226 */
227
228static int of_bus_isa_match(struct device_node *np)
229{
230	return !strcmp(np->name, "isa");
231}
232
233static void of_bus_isa_count_cells(struct device_node *child,
234				   int *addrc, int *sizec)
235{
236	if (addrc)
237		*addrc = 2;
238	if (sizec)
239		*sizec = 1;
240}
241
242static u64 of_bus_isa_map(u32 *addr, const __be32 *range, int na, int ns,
243		int pna)
244{
245	u64 cp, s, da;
246
247	/* Check address type match */
248	if ((addr[0] ^ range[0]) & cpu_to_be32(1))
249		return OF_BAD_ADDR;
250
251	/* Read address values, skipping high cell */
252	cp = of_read_number(range + 1, na - 1);
253	s  = of_read_number(range + na + pna, ns);
254	da = of_read_number(addr + 1, na - 1);
255
256	pr_debug("OF: ISA map, cp=%llx, s=%llx, da=%llx\n",
257		 (unsigned long long)cp, (unsigned long long)s,
258		 (unsigned long long)da);
259
260	if (da < cp || da >= (cp + s))
261		return OF_BAD_ADDR;
262	return da - cp;
263}
264
265static int of_bus_isa_translate(u32 *addr, u64 offset, int na)
266{
267	return of_bus_default_translate(addr + 1, offset, na - 1);
268}
269
270static unsigned int of_bus_isa_get_flags(const __be32 *addr)
271{
272	unsigned int flags = 0;
273	u32 w = be32_to_cpup(addr);
274
275	if (w & 1)
276		flags |= IORESOURCE_IO;
277	else
278		flags |= IORESOURCE_MEM;
279	return flags;
280}
281
282/*
283 * Array of bus specific translators
284 */
285
286static struct of_bus of_busses[] = {
287#ifdef CONFIG_PCI
288	/* PCI */
289	{
290		.name = "pci",
291		.addresses = "assigned-addresses",
292		.match = of_bus_pci_match,
293		.count_cells = of_bus_pci_count_cells,
294		.map = of_bus_pci_map,
295		.translate = of_bus_pci_translate,
296		.get_flags = of_bus_pci_get_flags,
297	},
298#endif /* CONFIG_PCI */
299	/* ISA */
300	{
301		.name = "isa",
302		.addresses = "reg",
303		.match = of_bus_isa_match,
304		.count_cells = of_bus_isa_count_cells,
305		.map = of_bus_isa_map,
306		.translate = of_bus_isa_translate,
307		.get_flags = of_bus_isa_get_flags,
308	},
309	/* Default */
310	{
311		.name = "default",
312		.addresses = "reg",
313		.match = NULL,
314		.count_cells = of_bus_default_count_cells,
315		.map = of_bus_default_map,
316		.translate = of_bus_default_translate,
317		.get_flags = of_bus_default_get_flags,
318	},
319};
320
321static struct of_bus *of_match_bus(struct device_node *np)
322{
323	int i;
324
325	for (i = 0; i < ARRAY_SIZE(of_busses); i++)
326		if (!of_busses[i].match || of_busses[i].match(np))
327			return &of_busses[i];
328	BUG();
329	return NULL;
330}
331
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
332static int of_translate_one(struct device_node *parent, struct of_bus *bus,
333			    struct of_bus *pbus, u32 *addr,
334			    int na, int ns, int pna, const char *rprop)
335{
336	const __be32 *ranges;
337	unsigned int rlen;
338	int rone;
339	u64 offset = OF_BAD_ADDR;
340
341	/* Normally, an absence of a "ranges" property means we are
 
342	 * crossing a non-translatable boundary, and thus the addresses
343	 * below the current not cannot be converted to CPU physical ones.
344	 * Unfortunately, while this is very clear in the spec, it's not
345	 * what Apple understood, and they do have things like /uni-n or
346	 * /ht nodes with no "ranges" property and a lot of perfectly
347	 * useable mapped devices below them. Thus we treat the absence of
348	 * "ranges" as equivalent to an empty "ranges" property which means
349	 * a 1:1 translation at that level. It's up to the caller not to try
350	 * to translate addresses that aren't supposed to be translated in
351	 * the first place. --BenH.
352	 *
353	 * As far as we know, this damage only exists on Apple machines, so
354	 * This code is only enabled on powerpc. --gcl
355	 */
356	ranges = of_get_property(parent, rprop, &rlen);
357#if !defined(CONFIG_PPC)
358	if (ranges == NULL) {
359		pr_err("OF: no ranges; cannot translate\n");
360		return 1;
361	}
362#endif /* !defined(CONFIG_PPC) */
363	if (ranges == NULL || rlen == 0) {
364		offset = of_read_number(addr, na);
365		memset(addr, 0, pna * 4);
366		pr_debug("OF: empty ranges; 1:1 translation\n");
367		goto finish;
368	}
369
370	pr_debug("OF: walking ranges...\n");
371
372	/* Now walk through the ranges */
373	rlen /= 4;
374	rone = na + pna + ns;
375	for (; rlen >= rone; rlen -= rone, ranges += rone) {
376		offset = bus->map(addr, ranges, na, ns, pna);
377		if (offset != OF_BAD_ADDR)
378			break;
379	}
380	if (offset == OF_BAD_ADDR) {
381		pr_debug("OF: not found !\n");
382		return 1;
383	}
384	memcpy(addr, ranges + na, 4 * pna);
385
386 finish:
387	of_dump_addr("OF: parent translation for:", addr, pna);
388	pr_debug("OF: with offset: %llx\n", (unsigned long long)offset);
389
390	/* Translate it into parent bus space */
391	return pbus->translate(addr, offset, pna);
392}
393
394/*
395 * Translate an address from the device-tree into a CPU physical address,
396 * this walks up the tree and applies the various bus mappings on the
397 * way.
398 *
399 * Note: We consider that crossing any level with #size-cells == 0 to mean
400 * that translation is impossible (that is we are not dealing with a value
401 * that can be mapped to a cpu physical address). This is not really specified
402 * that way, but this is traditionally the way IBM at least do things
 
 
 
 
403 */
404u64 __of_translate_address(struct device_node *dev, const __be32 *in_addr,
405			   const char *rprop)
 
 
406{
407	struct device_node *parent = NULL;
408	struct of_bus *bus, *pbus;
409	u32 addr[OF_MAX_ADDR_CELLS];
410	int na, ns, pna, pns;
411	u64 result = OF_BAD_ADDR;
412
413	pr_debug("OF: ** translation for device %s **\n", dev->full_name);
414
415	/* Increase refcount at current level */
416	of_node_get(dev);
417
 
418	/* Get parent & match bus type */
419	parent = of_get_parent(dev);
420	if (parent == NULL)
421		goto bail;
422	bus = of_match_bus(parent);
423
424	/* Cound address cells & copy address locally */
425	bus->count_cells(dev, &na, &ns);
426	if (!OF_CHECK_COUNTS(na, ns)) {
427		printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
428		       dev->full_name);
429		goto bail;
430	}
431	memcpy(addr, in_addr, na * 4);
432
433	pr_debug("OF: bus is %s (na=%d, ns=%d) on %s\n",
434	    bus->name, na, ns, parent->full_name);
435	of_dump_addr("OF: translating address:", addr, na);
436
437	/* Translate */
438	for (;;) {
 
 
439		/* Switch to parent bus */
440		of_node_put(dev);
441		dev = parent;
442		parent = of_get_parent(dev);
443
444		/* If root, we have finished */
445		if (parent == NULL) {
446			pr_debug("OF: reached root node\n");
447			result = of_read_number(addr, na);
448			break;
449		}
450
 
 
 
 
 
 
 
 
 
 
 
 
 
451		/* Get new parent bus and counts */
452		pbus = of_match_bus(parent);
453		pbus->count_cells(dev, &pna, &pns);
454		if (!OF_CHECK_COUNTS(pna, pns)) {
455			printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
456			       dev->full_name);
457			break;
458		}
459
460		pr_debug("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
461		    pbus->name, pna, pns, parent->full_name);
462
463		/* Apply bus translation */
464		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
465			break;
466
467		/* Complete the move up one level */
468		na = pna;
469		ns = pns;
470		bus = pbus;
471
472		of_dump_addr("OF: one level translation:", addr, na);
473	}
474 bail:
475	of_node_put(parent);
476	of_node_put(dev);
477
478	return result;
479}
480
481u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
482{
483	return __of_translate_address(dev, in_addr, "ranges");
 
 
 
 
 
 
 
 
 
 
484}
485EXPORT_SYMBOL(of_translate_address);
486
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
487u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
488{
489	return __of_translate_address(dev, in_addr, "dma-ranges");
 
 
 
 
 
 
 
 
 
 
 
490}
491EXPORT_SYMBOL(of_translate_dma_address);
492
493const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
494		    unsigned int *flags)
495{
496	const __be32 *prop;
497	unsigned int psize;
498	struct device_node *parent;
499	struct of_bus *bus;
500	int onesize, i, na, ns;
501
502	/* Get parent & match bus type */
503	parent = of_get_parent(dev);
504	if (parent == NULL)
505		return NULL;
506	bus = of_match_bus(parent);
507	bus->count_cells(dev, &na, &ns);
508	of_node_put(parent);
509	if (!OF_CHECK_COUNTS(na, ns))
510		return NULL;
511
512	/* Get "reg" or "assigned-addresses" property */
513	prop = of_get_property(dev, bus->addresses, &psize);
514	if (prop == NULL)
515		return NULL;
516	psize /= 4;
517
518	onesize = na + ns;
519	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
520		if (i == index) {
521			if (size)
522				*size = of_read_number(prop + na, ns);
523			if (flags)
524				*flags = bus->get_flags(prop);
525			return prop;
526		}
527	return NULL;
528}
529EXPORT_SYMBOL(of_get_address);
530
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
531static int __of_address_to_resource(struct device_node *dev,
532		const __be32 *addrp, u64 size, unsigned int flags,
533		const char *name, struct resource *r)
534{
535	u64 taddr;
536
537	if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
 
 
 
 
538		return -EINVAL;
539	taddr = of_translate_address(dev, addrp);
540	if (taddr == OF_BAD_ADDR)
541		return -EINVAL;
542	memset(r, 0, sizeof(struct resource));
543	if (flags & IORESOURCE_IO) {
544		unsigned long port;
545		port = pci_address_to_pio(taddr);
546		if (port == (unsigned long)-1)
547			return -EINVAL;
548		r->start = port;
549		r->end = port + size - 1;
550	} else {
551		r->start = taddr;
552		r->end = taddr + size - 1;
553	}
554	r->flags = flags;
555	r->name = name ? name : dev->full_name;
556
557	return 0;
558}
559
560/**
561 * of_address_to_resource - Translate device tree address and return as resource
562 *
563 * Note that if your address is a PIO address, the conversion will fail if
564 * the physical address can't be internally converted to an IO token with
565 * pci_address_to_pio(), that is because it's either called to early or it
566 * can't be matched to any host bridge IO space
567 */
568int of_address_to_resource(struct device_node *dev, int index,
569			   struct resource *r)
570{
571	const __be32	*addrp;
572	u64		size;
573	unsigned int	flags;
574	const char	*name = NULL;
575
576	addrp = of_get_address(dev, index, &size, &flags);
577	if (addrp == NULL)
578		return -EINVAL;
579
580	/* Get optional "reg-names" property to add a name to a resource */
581	of_property_read_string_index(dev, "reg-names",	index, &name);
582
583	return __of_address_to_resource(dev, addrp, size, flags, name, r);
584}
585EXPORT_SYMBOL_GPL(of_address_to_resource);
586
587struct device_node *of_find_matching_node_by_address(struct device_node *from,
588					const struct of_device_id *matches,
589					u64 base_address)
590{
591	struct device_node *dn = of_find_matching_node(from, matches);
592	struct resource res;
593
594	while (dn) {
595		if (of_address_to_resource(dn, 0, &res))
596			continue;
597		if (res.start == base_address)
598			return dn;
 
599		dn = of_find_matching_node(dn, matches);
600	}
601
602	return NULL;
603}
604
605
606/**
607 * of_iomap - Maps the memory mapped IO for a given device_node
608 * @device:	the device whose io range will be mapped
609 * @index:	index of the io range
610 *
611 * Returns a pointer to the mapped memory
612 */
613void __iomem *of_iomap(struct device_node *np, int index)
614{
615	struct resource res;
616
617	if (of_address_to_resource(np, index, &res))
618		return NULL;
619
620	return ioremap(res.start, resource_size(&res));
621}
622EXPORT_SYMBOL(of_iomap);
v5.4
   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
  17/* Max address size we deal with */
  18#define OF_MAX_ADDR_CELLS	4
  19#define OF_CHECK_ADDR_COUNT(na)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
  20#define OF_CHECK_COUNTS(na, ns)	(OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
  21
  22static struct of_bus *of_match_bus(struct device_node *np);
  23static int __of_address_to_resource(struct device_node *dev,
  24		const __be32 *addrp, u64 size, unsigned int flags,
  25		const char *name, struct resource *r);
  26
  27/* Debug utility */
  28#ifdef DEBUG
  29static void of_dump_addr(const char *s, const __be32 *addr, int na)
  30{
  31	pr_debug("%s", s);
  32	while (na--)
  33		pr_cont(" %08x", be32_to_cpu(*(addr++)));
  34	pr_cont("\n");
  35}
  36#else
  37static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
  38#endif
  39
  40/* Callbacks for bus specific translators */
  41struct of_bus {
  42	const char	*name;
  43	const char	*addresses;
  44	int		(*match)(struct device_node *parent);
  45	void		(*count_cells)(struct device_node *child,
  46				       int *addrc, int *sizec);
  47	u64		(*map)(__be32 *addr, const __be32 *range,
  48				int na, int ns, int pna);
  49	int		(*translate)(__be32 *addr, u64 offset, int na);
  50	unsigned int	(*get_flags)(const __be32 *addr);
  51};
  52
  53/*
  54 * Default translator (generic bus)
  55 */
  56
  57static void of_bus_default_count_cells(struct device_node *dev,
  58				       int *addrc, int *sizec)
  59{
  60	if (addrc)
  61		*addrc = of_n_addr_cells(dev);
  62	if (sizec)
  63		*sizec = of_n_size_cells(dev);
  64}
  65
  66static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
  67		int na, int ns, int pna)
  68{
  69	u64 cp, s, da;
  70
  71	cp = of_read_number(range, na);
  72	s  = of_read_number(range + na + pna, ns);
  73	da = of_read_number(addr, na);
  74
  75	pr_debug("default map, cp=%llx, s=%llx, da=%llx\n",
  76		 (unsigned long long)cp, (unsigned long long)s,
  77		 (unsigned long long)da);
  78
  79	if (da < cp || da >= (cp + s))
  80		return OF_BAD_ADDR;
  81	return da - cp;
  82}
  83
  84static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
  85{
  86	u64 a = of_read_number(addr, na);
  87	memset(addr, 0, na * 4);
  88	a += offset;
  89	if (na > 1)
  90		addr[na - 2] = cpu_to_be32(a >> 32);
  91	addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
  92
  93	return 0;
  94}
  95
  96static unsigned int of_bus_default_get_flags(const __be32 *addr)
  97{
  98	return IORESOURCE_MEM;
  99}
 100
 101#ifdef CONFIG_PCI
 102/*
 103 * PCI bus specific translator
 104 */
 105
 106static int of_bus_pci_match(struct device_node *np)
 107{
 108	/*
 109 	 * "pciex" is PCI Express
 110	 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
 111	 * "ht" is hypertransport
 112	 */
 113	return of_node_is_type(np, "pci") || of_node_is_type(np, "pciex") ||
 114		of_node_is_type(np, "vci") || of_node_is_type(np, "ht");
 115}
 116
 117static void of_bus_pci_count_cells(struct device_node *np,
 118				   int *addrc, int *sizec)
 119{
 120	if (addrc)
 121		*addrc = 3;
 122	if (sizec)
 123		*sizec = 2;
 124}
 125
 126static unsigned int of_bus_pci_get_flags(const __be32 *addr)
 127{
 128	unsigned int flags = 0;
 129	u32 w = be32_to_cpup(addr);
 130
 131	switch((w >> 24) & 0x03) {
 132	case 0x01:
 133		flags |= IORESOURCE_IO;
 134		break;
 135	case 0x02: /* 32 bits */
 136	case 0x03: /* 64 bits */
 137		flags |= IORESOURCE_MEM;
 138		break;
 139	}
 140	if (w & 0x40000000)
 141		flags |= IORESOURCE_PREFETCH;
 142	return flags;
 143}
 144
 145static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
 146		int pna)
 147{
 148	u64 cp, s, da;
 149	unsigned int af, rf;
 150
 151	af = of_bus_pci_get_flags(addr);
 152	rf = of_bus_pci_get_flags(range);
 153
 154	/* Check address type match */
 155	if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
 156		return OF_BAD_ADDR;
 157
 158	/* Read address values, skipping high cell */
 159	cp = of_read_number(range + 1, na - 1);
 160	s  = of_read_number(range + na + pna, ns);
 161	da = of_read_number(addr + 1, na - 1);
 162
 163	pr_debug("PCI map, cp=%llx, s=%llx, da=%llx\n",
 164		 (unsigned long long)cp, (unsigned long long)s,
 165		 (unsigned long long)da);
 166
 167	if (da < cp || da >= (cp + s))
 168		return OF_BAD_ADDR;
 169	return da - cp;
 170}
 171
 172static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
 173{
 174	return of_bus_default_translate(addr + 1, offset, na - 1);
 175}
 176
 177const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
 178			unsigned int *flags)
 179{
 180	const __be32 *prop;
 181	unsigned int psize;
 182	struct device_node *parent;
 183	struct of_bus *bus;
 184	int onesize, i, na, ns;
 185
 186	/* Get parent & match bus type */
 187	parent = of_get_parent(dev);
 188	if (parent == NULL)
 189		return NULL;
 190	bus = of_match_bus(parent);
 191	if (strcmp(bus->name, "pci")) {
 192		of_node_put(parent);
 193		return NULL;
 194	}
 195	bus->count_cells(dev, &na, &ns);
 196	of_node_put(parent);
 197	if (!OF_CHECK_ADDR_COUNT(na))
 198		return NULL;
 199
 200	/* Get "reg" or "assigned-addresses" property */
 201	prop = of_get_property(dev, bus->addresses, &psize);
 202	if (prop == NULL)
 203		return NULL;
 204	psize /= 4;
 205
 206	onesize = na + ns;
 207	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
 208		u32 val = be32_to_cpu(prop[0]);
 209		if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
 210			if (size)
 211				*size = of_read_number(prop + na, ns);
 212			if (flags)
 213				*flags = bus->get_flags(prop);
 214			return prop;
 215		}
 216	}
 217	return NULL;
 218}
 219EXPORT_SYMBOL(of_get_pci_address);
 220
 221int of_pci_address_to_resource(struct device_node *dev, int bar,
 222			       struct resource *r)
 223{
 224	const __be32	*addrp;
 225	u64		size;
 226	unsigned int	flags;
 227
 228	addrp = of_get_pci_address(dev, bar, &size, &flags);
 229	if (addrp == NULL)
 230		return -EINVAL;
 231	return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
 232}
 233EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
 234
 235static int parser_init(struct of_pci_range_parser *parser,
 236			struct device_node *node, const char *name)
 237{
 238	const int na = 3, ns = 2;
 239	int rlen;
 240
 241	parser->node = node;
 242	parser->pna = of_n_addr_cells(node);
 243	parser->np = parser->pna + na + ns;
 244
 245	parser->range = of_get_property(node, name, &rlen);
 246	if (parser->range == NULL)
 247		return -ENOENT;
 248
 249	parser->end = parser->range + rlen / sizeof(__be32);
 250
 251	return 0;
 252}
 253
 254int of_pci_range_parser_init(struct of_pci_range_parser *parser,
 255				struct device_node *node)
 256{
 257	return parser_init(parser, node, "ranges");
 258}
 259EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
 260
 261int of_pci_dma_range_parser_init(struct of_pci_range_parser *parser,
 262				struct device_node *node)
 263{
 264	return parser_init(parser, node, "dma-ranges");
 265}
 266EXPORT_SYMBOL_GPL(of_pci_dma_range_parser_init);
 267
 268struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
 269						struct of_pci_range *range)
 270{
 271	const int na = 3, ns = 2;
 272
 273	if (!range)
 274		return NULL;
 275
 276	if (!parser->range || parser->range + parser->np > parser->end)
 277		return NULL;
 278
 279	range->pci_space = be32_to_cpup(parser->range);
 280	range->flags = of_bus_pci_get_flags(parser->range);
 281	range->pci_addr = of_read_number(parser->range + 1, ns);
 282	range->cpu_addr = of_translate_address(parser->node,
 283				parser->range + na);
 284	range->size = of_read_number(parser->range + parser->pna + na, ns);
 285
 286	parser->range += parser->np;
 287
 288	/* Now consume following elements while they are contiguous */
 289	while (parser->range + parser->np <= parser->end) {
 290		u32 flags;
 291		u64 pci_addr, cpu_addr, size;
 292
 293		flags = of_bus_pci_get_flags(parser->range);
 294		pci_addr = of_read_number(parser->range + 1, ns);
 295		cpu_addr = of_translate_address(parser->node,
 296				parser->range + na);
 297		size = of_read_number(parser->range + parser->pna + na, ns);
 298
 299		if (flags != range->flags)
 300			break;
 301		if (pci_addr != range->pci_addr + range->size ||
 302		    cpu_addr != range->cpu_addr + range->size)
 303			break;
 304
 305		range->size += size;
 306		parser->range += parser->np;
 307	}
 308
 309	return range;
 310}
 311EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
 312
 313/*
 314 * of_pci_range_to_resource - Create a resource from an of_pci_range
 315 * @range:	the PCI range that describes the resource
 316 * @np:		device node where the range belongs to
 317 * @res:	pointer to a valid resource that will be updated to
 318 *              reflect the values contained in the range.
 319 *
 320 * Returns EINVAL if the range cannot be converted to resource.
 321 *
 322 * Note that if the range is an IO range, the resource will be converted
 323 * using pci_address_to_pio() which can fail if it is called too early or
 324 * if the range cannot be matched to any host bridge IO space (our case here).
 325 * To guard against that we try to register the IO range first.
 326 * If that fails we know that pci_address_to_pio() will do too.
 327 */
 328int of_pci_range_to_resource(struct of_pci_range *range,
 329			     struct device_node *np, struct resource *res)
 330{
 331	int err;
 332	res->flags = range->flags;
 333	res->parent = res->child = res->sibling = NULL;
 334	res->name = np->full_name;
 335
 336	if (res->flags & IORESOURCE_IO) {
 337		unsigned long port;
 338		err = pci_register_io_range(&np->fwnode, range->cpu_addr,
 339				range->size);
 340		if (err)
 341			goto invalid_range;
 342		port = pci_address_to_pio(range->cpu_addr);
 343		if (port == (unsigned long)-1) {
 344			err = -EINVAL;
 345			goto invalid_range;
 346		}
 347		res->start = port;
 348	} else {
 349		if ((sizeof(resource_size_t) < 8) &&
 350		    upper_32_bits(range->cpu_addr)) {
 351			err = -EINVAL;
 352			goto invalid_range;
 353		}
 354
 355		res->start = range->cpu_addr;
 356	}
 357	res->end = res->start + range->size - 1;
 358	return 0;
 359
 360invalid_range:
 361	res->start = (resource_size_t)OF_BAD_ADDR;
 362	res->end = (resource_size_t)OF_BAD_ADDR;
 363	return err;
 364}
 365EXPORT_SYMBOL(of_pci_range_to_resource);
 366#endif /* CONFIG_PCI */
 367
 368/*
 369 * ISA bus specific translator
 370 */
 371
 372static int of_bus_isa_match(struct device_node *np)
 373{
 374	return of_node_name_eq(np, "isa");
 375}
 376
 377static void of_bus_isa_count_cells(struct device_node *child,
 378				   int *addrc, int *sizec)
 379{
 380	if (addrc)
 381		*addrc = 2;
 382	if (sizec)
 383		*sizec = 1;
 384}
 385
 386static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
 387		int pna)
 388{
 389	u64 cp, s, da;
 390
 391	/* Check address type match */
 392	if ((addr[0] ^ range[0]) & cpu_to_be32(1))
 393		return OF_BAD_ADDR;
 394
 395	/* Read address values, skipping high cell */
 396	cp = of_read_number(range + 1, na - 1);
 397	s  = of_read_number(range + na + pna, ns);
 398	da = of_read_number(addr + 1, na - 1);
 399
 400	pr_debug("ISA map, cp=%llx, s=%llx, da=%llx\n",
 401		 (unsigned long long)cp, (unsigned long long)s,
 402		 (unsigned long long)da);
 403
 404	if (da < cp || da >= (cp + s))
 405		return OF_BAD_ADDR;
 406	return da - cp;
 407}
 408
 409static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
 410{
 411	return of_bus_default_translate(addr + 1, offset, na - 1);
 412}
 413
 414static unsigned int of_bus_isa_get_flags(const __be32 *addr)
 415{
 416	unsigned int flags = 0;
 417	u32 w = be32_to_cpup(addr);
 418
 419	if (w & 1)
 420		flags |= IORESOURCE_IO;
 421	else
 422		flags |= IORESOURCE_MEM;
 423	return flags;
 424}
 425
 426/*
 427 * Array of bus specific translators
 428 */
 429
 430static struct of_bus of_busses[] = {
 431#ifdef CONFIG_PCI
 432	/* PCI */
 433	{
 434		.name = "pci",
 435		.addresses = "assigned-addresses",
 436		.match = of_bus_pci_match,
 437		.count_cells = of_bus_pci_count_cells,
 438		.map = of_bus_pci_map,
 439		.translate = of_bus_pci_translate,
 440		.get_flags = of_bus_pci_get_flags,
 441	},
 442#endif /* CONFIG_PCI */
 443	/* ISA */
 444	{
 445		.name = "isa",
 446		.addresses = "reg",
 447		.match = of_bus_isa_match,
 448		.count_cells = of_bus_isa_count_cells,
 449		.map = of_bus_isa_map,
 450		.translate = of_bus_isa_translate,
 451		.get_flags = of_bus_isa_get_flags,
 452	},
 453	/* Default */
 454	{
 455		.name = "default",
 456		.addresses = "reg",
 457		.match = NULL,
 458		.count_cells = of_bus_default_count_cells,
 459		.map = of_bus_default_map,
 460		.translate = of_bus_default_translate,
 461		.get_flags = of_bus_default_get_flags,
 462	},
 463};
 464
 465static struct of_bus *of_match_bus(struct device_node *np)
 466{
 467	int i;
 468
 469	for (i = 0; i < ARRAY_SIZE(of_busses); i++)
 470		if (!of_busses[i].match || of_busses[i].match(np))
 471			return &of_busses[i];
 472	BUG();
 473	return NULL;
 474}
 475
 476static int of_empty_ranges_quirk(struct device_node *np)
 477{
 478	if (IS_ENABLED(CONFIG_PPC)) {
 479		/* To save cycles, we cache the result for global "Mac" setting */
 480		static int quirk_state = -1;
 481
 482		/* PA-SEMI sdc DT bug */
 483		if (of_device_is_compatible(np, "1682m-sdc"))
 484			return true;
 485
 486		/* Make quirk cached */
 487		if (quirk_state < 0)
 488			quirk_state =
 489				of_machine_is_compatible("Power Macintosh") ||
 490				of_machine_is_compatible("MacRISC");
 491		return quirk_state;
 492	}
 493	return false;
 494}
 495
 496static int of_translate_one(struct device_node *parent, struct of_bus *bus,
 497			    struct of_bus *pbus, __be32 *addr,
 498			    int na, int ns, int pna, const char *rprop)
 499{
 500	const __be32 *ranges;
 501	unsigned int rlen;
 502	int rone;
 503	u64 offset = OF_BAD_ADDR;
 504
 505	/*
 506	 * Normally, an absence of a "ranges" property means we are
 507	 * crossing a non-translatable boundary, and thus the addresses
 508	 * below the current cannot be converted to CPU physical ones.
 509	 * Unfortunately, while this is very clear in the spec, it's not
 510	 * what Apple understood, and they do have things like /uni-n or
 511	 * /ht nodes with no "ranges" property and a lot of perfectly
 512	 * useable mapped devices below them. Thus we treat the absence of
 513	 * "ranges" as equivalent to an empty "ranges" property which means
 514	 * a 1:1 translation at that level. It's up to the caller not to try
 515	 * to translate addresses that aren't supposed to be translated in
 516	 * the first place. --BenH.
 517	 *
 518	 * As far as we know, this damage only exists on Apple machines, so
 519	 * This code is only enabled on powerpc. --gcl
 520	 */
 521	ranges = of_get_property(parent, rprop, &rlen);
 522	if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
 523		pr_debug("no ranges; cannot translate\n");
 
 524		return 1;
 525	}
 
 526	if (ranges == NULL || rlen == 0) {
 527		offset = of_read_number(addr, na);
 528		memset(addr, 0, pna * 4);
 529		pr_debug("empty ranges; 1:1 translation\n");
 530		goto finish;
 531	}
 532
 533	pr_debug("walking ranges...\n");
 534
 535	/* Now walk through the ranges */
 536	rlen /= 4;
 537	rone = na + pna + ns;
 538	for (; rlen >= rone; rlen -= rone, ranges += rone) {
 539		offset = bus->map(addr, ranges, na, ns, pna);
 540		if (offset != OF_BAD_ADDR)
 541			break;
 542	}
 543	if (offset == OF_BAD_ADDR) {
 544		pr_debug("not found !\n");
 545		return 1;
 546	}
 547	memcpy(addr, ranges + na, 4 * pna);
 548
 549 finish:
 550	of_dump_addr("parent translation for:", addr, pna);
 551	pr_debug("with offset: %llx\n", (unsigned long long)offset);
 552
 553	/* Translate it into parent bus space */
 554	return pbus->translate(addr, offset, pna);
 555}
 556
 557/*
 558 * Translate an address from the device-tree into a CPU physical address,
 559 * this walks up the tree and applies the various bus mappings on the
 560 * way.
 561 *
 562 * Note: We consider that crossing any level with #size-cells == 0 to mean
 563 * that translation is impossible (that is we are not dealing with a value
 564 * that can be mapped to a cpu physical address). This is not really specified
 565 * that way, but this is traditionally the way IBM at least do things
 566 *
 567 * Whenever the translation fails, the *host pointer will be set to the
 568 * device that had registered logical PIO mapping, and the return code is
 569 * relative to that node.
 570 */
 571static u64 __of_translate_address(struct device_node *dev,
 572				  struct device_node *(*get_parent)(const struct device_node *),
 573				  const __be32 *in_addr, const char *rprop,
 574				  struct device_node **host)
 575{
 576	struct device_node *parent = NULL;
 577	struct of_bus *bus, *pbus;
 578	__be32 addr[OF_MAX_ADDR_CELLS];
 579	int na, ns, pna, pns;
 580	u64 result = OF_BAD_ADDR;
 581
 582	pr_debug("** translation for device %pOF **\n", dev);
 583
 584	/* Increase refcount at current level */
 585	of_node_get(dev);
 586
 587	*host = NULL;
 588	/* Get parent & match bus type */
 589	parent = get_parent(dev);
 590	if (parent == NULL)
 591		goto bail;
 592	bus = of_match_bus(parent);
 593
 594	/* Count address cells & copy address locally */
 595	bus->count_cells(dev, &na, &ns);
 596	if (!OF_CHECK_COUNTS(na, ns)) {
 597		pr_debug("Bad cell count for %pOF\n", dev);
 
 598		goto bail;
 599	}
 600	memcpy(addr, in_addr, na * 4);
 601
 602	pr_debug("bus is %s (na=%d, ns=%d) on %pOF\n",
 603	    bus->name, na, ns, parent);
 604	of_dump_addr("translating address:", addr, na);
 605
 606	/* Translate */
 607	for (;;) {
 608		struct logic_pio_hwaddr *iorange;
 609
 610		/* Switch to parent bus */
 611		of_node_put(dev);
 612		dev = parent;
 613		parent = get_parent(dev);
 614
 615		/* If root, we have finished */
 616		if (parent == NULL) {
 617			pr_debug("reached root node\n");
 618			result = of_read_number(addr, na);
 619			break;
 620		}
 621
 622		/*
 623		 * For indirectIO device which has no ranges property, get
 624		 * the address from reg directly.
 625		 */
 626		iorange = find_io_range_by_fwnode(&dev->fwnode);
 627		if (iorange && (iorange->flags != LOGIC_PIO_CPU_MMIO)) {
 628			result = of_read_number(addr + 1, na - 1);
 629			pr_debug("indirectIO matched(%pOF) 0x%llx\n",
 630				 dev, result);
 631			*host = of_node_get(dev);
 632			break;
 633		}
 634
 635		/* Get new parent bus and counts */
 636		pbus = of_match_bus(parent);
 637		pbus->count_cells(dev, &pna, &pns);
 638		if (!OF_CHECK_COUNTS(pna, pns)) {
 639			pr_err("Bad cell count for %pOF\n", dev);
 
 640			break;
 641		}
 642
 643		pr_debug("parent bus is %s (na=%d, ns=%d) on %pOF\n",
 644		    pbus->name, pna, pns, parent);
 645
 646		/* Apply bus translation */
 647		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
 648			break;
 649
 650		/* Complete the move up one level */
 651		na = pna;
 652		ns = pns;
 653		bus = pbus;
 654
 655		of_dump_addr("one level translation:", addr, na);
 656	}
 657 bail:
 658	of_node_put(parent);
 659	of_node_put(dev);
 660
 661	return result;
 662}
 663
 664u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
 665{
 666	struct device_node *host;
 667	u64 ret;
 668
 669	ret = __of_translate_address(dev, of_get_parent,
 670				     in_addr, "ranges", &host);
 671	if (host) {
 672		of_node_put(host);
 673		return OF_BAD_ADDR;
 674	}
 675
 676	return ret;
 677}
 678EXPORT_SYMBOL(of_translate_address);
 679
 680static struct device_node *__of_get_dma_parent(const struct device_node *np)
 681{
 682	struct of_phandle_args args;
 683	int ret, index;
 684
 685	index = of_property_match_string(np, "interconnect-names", "dma-mem");
 686	if (index < 0)
 687		return of_get_parent(np);
 688
 689	ret = of_parse_phandle_with_args(np, "interconnects",
 690					 "#interconnect-cells",
 691					 index, &args);
 692	if (ret < 0)
 693		return of_get_parent(np);
 694
 695	return of_node_get(args.np);
 696}
 697
 698u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
 699{
 700	struct device_node *host;
 701	u64 ret;
 702
 703	ret = __of_translate_address(dev, __of_get_dma_parent,
 704				     in_addr, "dma-ranges", &host);
 705
 706	if (host) {
 707		of_node_put(host);
 708		return OF_BAD_ADDR;
 709	}
 710
 711	return ret;
 712}
 713EXPORT_SYMBOL(of_translate_dma_address);
 714
 715const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
 716		    unsigned int *flags)
 717{
 718	const __be32 *prop;
 719	unsigned int psize;
 720	struct device_node *parent;
 721	struct of_bus *bus;
 722	int onesize, i, na, ns;
 723
 724	/* Get parent & match bus type */
 725	parent = of_get_parent(dev);
 726	if (parent == NULL)
 727		return NULL;
 728	bus = of_match_bus(parent);
 729	bus->count_cells(dev, &na, &ns);
 730	of_node_put(parent);
 731	if (!OF_CHECK_ADDR_COUNT(na))
 732		return NULL;
 733
 734	/* Get "reg" or "assigned-addresses" property */
 735	prop = of_get_property(dev, bus->addresses, &psize);
 736	if (prop == NULL)
 737		return NULL;
 738	psize /= 4;
 739
 740	onesize = na + ns;
 741	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
 742		if (i == index) {
 743			if (size)
 744				*size = of_read_number(prop + na, ns);
 745			if (flags)
 746				*flags = bus->get_flags(prop);
 747			return prop;
 748		}
 749	return NULL;
 750}
 751EXPORT_SYMBOL(of_get_address);
 752
 753static u64 of_translate_ioport(struct device_node *dev, const __be32 *in_addr,
 754			u64 size)
 755{
 756	u64 taddr;
 757	unsigned long port;
 758	struct device_node *host;
 759
 760	taddr = __of_translate_address(dev, of_get_parent,
 761				       in_addr, "ranges", &host);
 762	if (host) {
 763		/* host-specific port access */
 764		port = logic_pio_trans_hwaddr(&host->fwnode, taddr, size);
 765		of_node_put(host);
 766	} else {
 767		/* memory-mapped I/O range */
 768		port = pci_address_to_pio(taddr);
 769	}
 770
 771	if (port == (unsigned long)-1)
 772		return OF_BAD_ADDR;
 773
 774	return port;
 775}
 776
 777static int __of_address_to_resource(struct device_node *dev,
 778		const __be32 *addrp, u64 size, unsigned int flags,
 779		const char *name, struct resource *r)
 780{
 781	u64 taddr;
 782
 783	if (flags & IORESOURCE_MEM)
 784		taddr = of_translate_address(dev, addrp);
 785	else if (flags & IORESOURCE_IO)
 786		taddr = of_translate_ioport(dev, addrp, size);
 787	else
 788		return -EINVAL;
 789
 790	if (taddr == OF_BAD_ADDR)
 791		return -EINVAL;
 792	memset(r, 0, sizeof(struct resource));
 793
 794	r->start = taddr;
 795	r->end = taddr + size - 1;
 
 
 
 
 
 
 
 
 796	r->flags = flags;
 797	r->name = name ? name : dev->full_name;
 798
 799	return 0;
 800}
 801
 802/**
 803 * of_address_to_resource - Translate device tree address and return as resource
 804 *
 805 * Note that if your address is a PIO address, the conversion will fail if
 806 * the physical address can't be internally converted to an IO token with
 807 * pci_address_to_pio(), that is because it's either called too early or it
 808 * can't be matched to any host bridge IO space
 809 */
 810int of_address_to_resource(struct device_node *dev, int index,
 811			   struct resource *r)
 812{
 813	const __be32	*addrp;
 814	u64		size;
 815	unsigned int	flags;
 816	const char	*name = NULL;
 817
 818	addrp = of_get_address(dev, index, &size, &flags);
 819	if (addrp == NULL)
 820		return -EINVAL;
 821
 822	/* Get optional "reg-names" property to add a name to a resource */
 823	of_property_read_string_index(dev, "reg-names",	index, &name);
 824
 825	return __of_address_to_resource(dev, addrp, size, flags, name, r);
 826}
 827EXPORT_SYMBOL_GPL(of_address_to_resource);
 828
 829struct device_node *of_find_matching_node_by_address(struct device_node *from,
 830					const struct of_device_id *matches,
 831					u64 base_address)
 832{
 833	struct device_node *dn = of_find_matching_node(from, matches);
 834	struct resource res;
 835
 836	while (dn) {
 837		if (!of_address_to_resource(dn, 0, &res) &&
 838		    res.start == base_address)
 
 839			return dn;
 840
 841		dn = of_find_matching_node(dn, matches);
 842	}
 843
 844	return NULL;
 845}
 846
 847
 848/**
 849 * of_iomap - Maps the memory mapped IO for a given device_node
 850 * @device:	the device whose io range will be mapped
 851 * @index:	index of the io range
 852 *
 853 * Returns a pointer to the mapped memory
 854 */
 855void __iomem *of_iomap(struct device_node *np, int index)
 856{
 857	struct resource res;
 858
 859	if (of_address_to_resource(np, index, &res))
 860		return NULL;
 861
 862	return ioremap(res.start, resource_size(&res));
 863}
 864EXPORT_SYMBOL(of_iomap);
 865
 866/*
 867 * of_io_request_and_map - Requests a resource and maps the memory mapped IO
 868 *			   for a given device_node
 869 * @device:	the device whose io range will be mapped
 870 * @index:	index of the io range
 871 * @name:	name "override" for the memory region request or NULL
 872 *
 873 * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
 874 * error code on failure. Usage example:
 875 *
 876 *	base = of_io_request_and_map(node, 0, "foo");
 877 *	if (IS_ERR(base))
 878 *		return PTR_ERR(base);
 879 */
 880void __iomem *of_io_request_and_map(struct device_node *np, int index,
 881				    const char *name)
 882{
 883	struct resource res;
 884	void __iomem *mem;
 885
 886	if (of_address_to_resource(np, index, &res))
 887		return IOMEM_ERR_PTR(-EINVAL);
 888
 889	if (!name)
 890		name = res.name;
 891	if (!request_mem_region(res.start, resource_size(&res), name))
 892		return IOMEM_ERR_PTR(-EBUSY);
 893
 894	mem = ioremap(res.start, resource_size(&res));
 895	if (!mem) {
 896		release_mem_region(res.start, resource_size(&res));
 897		return IOMEM_ERR_PTR(-ENOMEM);
 898	}
 899
 900	return mem;
 901}
 902EXPORT_SYMBOL(of_io_request_and_map);
 903
 904/**
 905 * of_dma_get_range - Get DMA range info
 906 * @np:		device node to get DMA range info
 907 * @dma_addr:	pointer to store initial DMA address of DMA range
 908 * @paddr:	pointer to store initial CPU address of DMA range
 909 * @size:	pointer to store size of DMA range
 910 *
 911 * Look in bottom up direction for the first "dma-ranges" property
 912 * and parse it.
 913 *  dma-ranges format:
 914 *	DMA addr (dma_addr)	: naddr cells
 915 *	CPU addr (phys_addr_t)	: pna cells
 916 *	size			: nsize cells
 917 *
 918 * It returns -ENODEV if "dma-ranges" property was not found
 919 * for this device in DT.
 920 */
 921int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
 922{
 923	struct device_node *node = of_node_get(np);
 924	const __be32 *ranges = NULL;
 925	int len, naddr, nsize, pna;
 926	int ret = 0;
 927	u64 dmaaddr;
 928
 929	if (!node)
 930		return -EINVAL;
 931
 932	while (1) {
 933		struct device_node *parent;
 934
 935		naddr = of_n_addr_cells(node);
 936		nsize = of_n_size_cells(node);
 937
 938		parent = __of_get_dma_parent(node);
 939		of_node_put(node);
 940
 941		node = parent;
 942		if (!node)
 943			break;
 944
 945		ranges = of_get_property(node, "dma-ranges", &len);
 946
 947		/* Ignore empty ranges, they imply no translation required */
 948		if (ranges && len > 0)
 949			break;
 950
 951		/*
 952		 * At least empty ranges has to be defined for parent node if
 953		 * DMA is supported
 954		 */
 955		if (!ranges)
 956			break;
 957	}
 958
 959	if (!ranges) {
 960		pr_debug("no dma-ranges found for node(%pOF)\n", np);
 961		ret = -ENODEV;
 962		goto out;
 963	}
 964
 965	len /= sizeof(u32);
 966
 967	pna = of_n_addr_cells(node);
 968
 969	/* dma-ranges format:
 970	 * DMA addr	: naddr cells
 971	 * CPU addr	: pna cells
 972	 * size		: nsize cells
 973	 */
 974	dmaaddr = of_read_number(ranges, naddr);
 975	*paddr = of_translate_dma_address(np, ranges);
 976	if (*paddr == OF_BAD_ADDR) {
 977		pr_err("translation of DMA address(%pad) to CPU address failed node(%pOF)\n",
 978		       dma_addr, np);
 979		ret = -EINVAL;
 980		goto out;
 981	}
 982	*dma_addr = dmaaddr;
 983
 984	*size = of_read_number(ranges + naddr + pna, nsize);
 985
 986	pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
 987		 *dma_addr, *paddr, *size);
 988
 989out:
 990	of_node_put(node);
 991
 992	return ret;
 993}
 994EXPORT_SYMBOL_GPL(of_dma_get_range);
 995
 996/**
 997 * of_dma_is_coherent - Check if device is coherent
 998 * @np:	device node
 999 *
1000 * It returns true if "dma-coherent" property was found
1001 * for this device in DT.
1002 */
1003bool of_dma_is_coherent(struct device_node *np)
1004{
1005	struct device_node *node = of_node_get(np);
1006
1007	while (node) {
1008		if (of_property_read_bool(node, "dma-coherent")) {
1009			of_node_put(node);
1010			return true;
1011		}
1012		node = of_get_next_parent(node);
1013	}
1014	of_node_put(node);
1015	return false;
1016}
1017EXPORT_SYMBOL_GPL(of_dma_is_coherent);