xref: /linux/drivers/of/address.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 
2 #include <linux/device.h>
3 #include <linux/io.h>
4 #include <linux/ioport.h>
5 #include <linux/module.h>
6 #include <linux/of_address.h>
7 #include <linux/pci_regs.h>
8 #include <linux/string.h>
9 
10 /* Max address size we deal with */
11 #define OF_MAX_ADDR_CELLS	4
12 #define OF_CHECK_ADDR_COUNT(na)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
13 #define OF_CHECK_COUNTS(na, ns)	(OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
14 
15 static struct of_bus *of_match_bus(struct device_node *np);
16 static int __of_address_to_resource(struct device_node *dev,
17 		const __be32 *addrp, u64 size, unsigned int flags,
18 		const char *name, struct resource *r);
19 
20 /* Debug utility */
21 #ifdef DEBUG
22 static void of_dump_addr(const char *s, const __be32 *addr, int na)
23 {
24 	printk(KERN_DEBUG "%s", s);
25 	while (na--)
26 		printk(" %08x", be32_to_cpu(*(addr++)));
27 	printk("\n");
28 }
29 #else
30 static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
31 #endif
32 
33 /* Callbacks for bus specific translators */
34 struct of_bus {
35 	const char	*name;
36 	const char	*addresses;
37 	int		(*match)(struct device_node *parent);
38 	void		(*count_cells)(struct device_node *child,
39 				       int *addrc, int *sizec);
40 	u64		(*map)(__be32 *addr, const __be32 *range,
41 				int na, int ns, int pna);
42 	int		(*translate)(__be32 *addr, u64 offset, int na);
43 	unsigned int	(*get_flags)(const __be32 *addr);
44 };
45 
46 /*
47  * Default translator (generic bus)
48  */
49 
50 static void of_bus_default_count_cells(struct device_node *dev,
51 				       int *addrc, int *sizec)
52 {
53 	if (addrc)
54 		*addrc = of_n_addr_cells(dev);
55 	if (sizec)
56 		*sizec = of_n_size_cells(dev);
57 }
58 
59 static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
60 		int na, int ns, int pna)
61 {
62 	u64 cp, s, da;
63 
64 	cp = of_read_number(range, na);
65 	s  = of_read_number(range + na + pna, ns);
66 	da = of_read_number(addr, na);
67 
68 	pr_debug("OF: default map, cp=%llx, s=%llx, da=%llx\n",
69 		 (unsigned long long)cp, (unsigned long long)s,
70 		 (unsigned long long)da);
71 
72 	/*
73 	 * If the number of address cells is larger than 2 we assume the
74 	 * mapping doesn't specify a physical address. Rather, the address
75 	 * specifies an identifier that must match exactly.
76 	 */
77 	if (na > 2 && memcmp(range, addr, na * 4) != 0)
78 		return OF_BAD_ADDR;
79 
80 	if (da < cp || da >= (cp + s))
81 		return OF_BAD_ADDR;
82 	return da - cp;
83 }
84 
85 static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
86 {
87 	u64 a = of_read_number(addr, na);
88 	memset(addr, 0, na * 4);
89 	a += offset;
90 	if (na > 1)
91 		addr[na - 2] = cpu_to_be32(a >> 32);
92 	addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
93 
94 	return 0;
95 }
96 
97 static unsigned int of_bus_default_get_flags(const __be32 *addr)
98 {
99 	return IORESOURCE_MEM;
100 }
101 
102 #ifdef CONFIG_PCI
103 /*
104  * PCI bus specific translator
105  */
106 
107 static int of_bus_pci_match(struct device_node *np)
108 {
109 	/* "vci" is for the /chaos bridge on 1st-gen PCI powermacs */
110 	return !strcmp(np->type, "pci") || !strcmp(np->type, "vci");
111 }
112 
113 static void of_bus_pci_count_cells(struct device_node *np,
114 				   int *addrc, int *sizec)
115 {
116 	if (addrc)
117 		*addrc = 3;
118 	if (sizec)
119 		*sizec = 2;
120 }
121 
122 static unsigned int of_bus_pci_get_flags(const __be32 *addr)
123 {
124 	unsigned int flags = 0;
125 	u32 w = be32_to_cpup(addr);
126 
127 	switch((w >> 24) & 0x03) {
128 	case 0x01:
129 		flags |= IORESOURCE_IO;
130 		break;
131 	case 0x02: /* 32 bits */
132 	case 0x03: /* 64 bits */
133 		flags |= IORESOURCE_MEM;
134 		break;
135 	}
136 	if (w & 0x40000000)
137 		flags |= IORESOURCE_PREFETCH;
138 	return flags;
139 }
140 
141 static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
142 		int pna)
143 {
144 	u64 cp, s, da;
145 	unsigned int af, rf;
146 
147 	af = of_bus_pci_get_flags(addr);
148 	rf = of_bus_pci_get_flags(range);
149 
150 	/* Check address type match */
151 	if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
152 		return OF_BAD_ADDR;
153 
154 	/* Read address values, skipping high cell */
155 	cp = of_read_number(range + 1, na - 1);
156 	s  = of_read_number(range + na + pna, ns);
157 	da = of_read_number(addr + 1, na - 1);
158 
159 	pr_debug("OF: PCI map, cp=%llx, s=%llx, da=%llx\n",
160 		 (unsigned long long)cp, (unsigned long long)s,
161 		 (unsigned long long)da);
162 
163 	if (da < cp || da >= (cp + s))
164 		return OF_BAD_ADDR;
165 	return da - cp;
166 }
167 
168 static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
169 {
170 	return of_bus_default_translate(addr + 1, offset, na - 1);
171 }
172 
173 const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
174 			unsigned int *flags)
175 {
176 	const __be32 *prop;
177 	unsigned int psize;
178 	struct device_node *parent;
179 	struct of_bus *bus;
180 	int onesize, i, na, ns;
181 
182 	/* Get parent & match bus type */
183 	parent = of_get_parent(dev);
184 	if (parent == NULL)
185 		return NULL;
186 	bus = of_match_bus(parent);
187 	if (strcmp(bus->name, "pci")) {
188 		of_node_put(parent);
189 		return NULL;
190 	}
191 	bus->count_cells(dev, &na, &ns);
192 	of_node_put(parent);
193 	if (!OF_CHECK_ADDR_COUNT(na))
194 		return NULL;
195 
196 	/* Get "reg" or "assigned-addresses" property */
197 	prop = of_get_property(dev, bus->addresses, &psize);
198 	if (prop == NULL)
199 		return NULL;
200 	psize /= 4;
201 
202 	onesize = na + ns;
203 	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
204 		u32 val = be32_to_cpu(prop[0]);
205 		if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
206 			if (size)
207 				*size = of_read_number(prop + na, ns);
208 			if (flags)
209 				*flags = bus->get_flags(prop);
210 			return prop;
211 		}
212 	}
213 	return NULL;
214 }
215 EXPORT_SYMBOL(of_get_pci_address);
216 
217 int of_pci_address_to_resource(struct device_node *dev, int bar,
218 			       struct resource *r)
219 {
220 	const __be32	*addrp;
221 	u64		size;
222 	unsigned int	flags;
223 
224 	addrp = of_get_pci_address(dev, bar, &size, &flags);
225 	if (addrp == NULL)
226 		return -EINVAL;
227 	return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
228 }
229 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
230 #endif /* CONFIG_PCI */
231 
232 /*
233  * ISA bus specific translator
234  */
235 
236 static int of_bus_isa_match(struct device_node *np)
237 {
238 	return !strcmp(np->name, "isa");
239 }
240 
241 static void of_bus_isa_count_cells(struct device_node *child,
242 				   int *addrc, int *sizec)
243 {
244 	if (addrc)
245 		*addrc = 2;
246 	if (sizec)
247 		*sizec = 1;
248 }
249 
250 static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
251 		int pna)
252 {
253 	u64 cp, s, da;
254 
255 	/* Check address type match */
256 	if ((addr[0] ^ range[0]) & cpu_to_be32(1))
257 		return OF_BAD_ADDR;
258 
259 	/* Read address values, skipping high cell */
260 	cp = of_read_number(range + 1, na - 1);
261 	s  = of_read_number(range + na + pna, ns);
262 	da = of_read_number(addr + 1, na - 1);
263 
264 	pr_debug("OF: ISA map, cp=%llx, s=%llx, da=%llx\n",
265 		 (unsigned long long)cp, (unsigned long long)s,
266 		 (unsigned long long)da);
267 
268 	if (da < cp || da >= (cp + s))
269 		return OF_BAD_ADDR;
270 	return da - cp;
271 }
272 
273 static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
274 {
275 	return of_bus_default_translate(addr + 1, offset, na - 1);
276 }
277 
278 static unsigned int of_bus_isa_get_flags(const __be32 *addr)
279 {
280 	unsigned int flags = 0;
281 	u32 w = be32_to_cpup(addr);
282 
283 	if (w & 1)
284 		flags |= IORESOURCE_IO;
285 	else
286 		flags |= IORESOURCE_MEM;
287 	return flags;
288 }
289 
290 /*
291  * Array of bus specific translators
292  */
293 
294 static struct of_bus of_busses[] = {
295 #ifdef CONFIG_PCI
296 	/* PCI */
297 	{
298 		.name = "pci",
299 		.addresses = "assigned-addresses",
300 		.match = of_bus_pci_match,
301 		.count_cells = of_bus_pci_count_cells,
302 		.map = of_bus_pci_map,
303 		.translate = of_bus_pci_translate,
304 		.get_flags = of_bus_pci_get_flags,
305 	},
306 #endif /* CONFIG_PCI */
307 	/* ISA */
308 	{
309 		.name = "isa",
310 		.addresses = "reg",
311 		.match = of_bus_isa_match,
312 		.count_cells = of_bus_isa_count_cells,
313 		.map = of_bus_isa_map,
314 		.translate = of_bus_isa_translate,
315 		.get_flags = of_bus_isa_get_flags,
316 	},
317 	/* Default */
318 	{
319 		.name = "default",
320 		.addresses = "reg",
321 		.match = NULL,
322 		.count_cells = of_bus_default_count_cells,
323 		.map = of_bus_default_map,
324 		.translate = of_bus_default_translate,
325 		.get_flags = of_bus_default_get_flags,
326 	},
327 };
328 
329 static struct of_bus *of_match_bus(struct device_node *np)
330 {
331 	int i;
332 
333 	for (i = 0; i < ARRAY_SIZE(of_busses); i++)
334 		if (!of_busses[i].match || of_busses[i].match(np))
335 			return &of_busses[i];
336 	BUG();
337 	return NULL;
338 }
339 
340 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
341 			    struct of_bus *pbus, __be32 *addr,
342 			    int na, int ns, int pna, const char *rprop)
343 {
344 	const __be32 *ranges;
345 	unsigned int rlen;
346 	int rone;
347 	u64 offset = OF_BAD_ADDR;
348 
349 	/* Normally, an absence of a "ranges" property means we are
350 	 * crossing a non-translatable boundary, and thus the addresses
351 	 * below the current not cannot be converted to CPU physical ones.
352 	 * Unfortunately, while this is very clear in the spec, it's not
353 	 * what Apple understood, and they do have things like /uni-n or
354 	 * /ht nodes with no "ranges" property and a lot of perfectly
355 	 * useable mapped devices below them. Thus we treat the absence of
356 	 * "ranges" as equivalent to an empty "ranges" property which means
357 	 * a 1:1 translation at that level. It's up to the caller not to try
358 	 * to translate addresses that aren't supposed to be translated in
359 	 * the first place. --BenH.
360 	 *
361 	 * As far as we know, this damage only exists on Apple machines, so
362 	 * This code is only enabled on powerpc. --gcl
363 	 */
364 	ranges = of_get_property(parent, rprop, &rlen);
365 #if !defined(CONFIG_PPC)
366 	if (ranges == NULL) {
367 		pr_err("OF: no ranges; cannot translate\n");
368 		return 1;
369 	}
370 #endif /* !defined(CONFIG_PPC) */
371 	if (ranges == NULL || rlen == 0) {
372 		offset = of_read_number(addr, na);
373 		memset(addr, 0, pna * 4);
374 		pr_debug("OF: empty ranges; 1:1 translation\n");
375 		goto finish;
376 	}
377 
378 	pr_debug("OF: walking ranges...\n");
379 
380 	/* Now walk through the ranges */
381 	rlen /= 4;
382 	rone = na + pna + ns;
383 	for (; rlen >= rone; rlen -= rone, ranges += rone) {
384 		offset = bus->map(addr, ranges, na, ns, pna);
385 		if (offset != OF_BAD_ADDR)
386 			break;
387 	}
388 	if (offset == OF_BAD_ADDR) {
389 		pr_debug("OF: not found !\n");
390 		return 1;
391 	}
392 	memcpy(addr, ranges + na, 4 * pna);
393 
394  finish:
395 	of_dump_addr("OF: parent translation for:", addr, pna);
396 	pr_debug("OF: with offset: %llx\n", (unsigned long long)offset);
397 
398 	/* Translate it into parent bus space */
399 	return pbus->translate(addr, offset, pna);
400 }
401 
402 /*
403  * Translate an address from the device-tree into a CPU physical address,
404  * this walks up the tree and applies the various bus mappings on the
405  * way.
406  *
407  * Note: We consider that crossing any level with #size-cells == 0 to mean
408  * that translation is impossible (that is we are not dealing with a value
409  * that can be mapped to a cpu physical address). This is not really specified
410  * that way, but this is traditionally the way IBM at least do things
411  */
412 static u64 __of_translate_address(struct device_node *dev,
413 				  const __be32 *in_addr, const char *rprop)
414 {
415 	struct device_node *parent = NULL;
416 	struct of_bus *bus, *pbus;
417 	__be32 addr[OF_MAX_ADDR_CELLS];
418 	int na, ns, pna, pns;
419 	u64 result = OF_BAD_ADDR;
420 
421 	pr_debug("OF: ** translation for device %s **\n", dev->full_name);
422 
423 	/* Increase refcount at current level */
424 	of_node_get(dev);
425 
426 	/* Get parent & match bus type */
427 	parent = of_get_parent(dev);
428 	if (parent == NULL)
429 		goto bail;
430 	bus = of_match_bus(parent);
431 
432 	/* Cound address cells & copy address locally */
433 	bus->count_cells(dev, &na, &ns);
434 	if (!OF_CHECK_COUNTS(na, ns)) {
435 		printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
436 		       dev->full_name);
437 		goto bail;
438 	}
439 	memcpy(addr, in_addr, na * 4);
440 
441 	pr_debug("OF: bus is %s (na=%d, ns=%d) on %s\n",
442 	    bus->name, na, ns, parent->full_name);
443 	of_dump_addr("OF: translating address:", addr, na);
444 
445 	/* Translate */
446 	for (;;) {
447 		/* Switch to parent bus */
448 		of_node_put(dev);
449 		dev = parent;
450 		parent = of_get_parent(dev);
451 
452 		/* If root, we have finished */
453 		if (parent == NULL) {
454 			pr_debug("OF: reached root node\n");
455 			result = of_read_number(addr, na);
456 			break;
457 		}
458 
459 		/* Get new parent bus and counts */
460 		pbus = of_match_bus(parent);
461 		pbus->count_cells(dev, &pna, &pns);
462 		if (!OF_CHECK_COUNTS(pna, pns)) {
463 			printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
464 			       dev->full_name);
465 			break;
466 		}
467 
468 		pr_debug("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
469 		    pbus->name, pna, pns, parent->full_name);
470 
471 		/* Apply bus translation */
472 		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
473 			break;
474 
475 		/* Complete the move up one level */
476 		na = pna;
477 		ns = pns;
478 		bus = pbus;
479 
480 		of_dump_addr("OF: one level translation:", addr, na);
481 	}
482  bail:
483 	of_node_put(parent);
484 	of_node_put(dev);
485 
486 	return result;
487 }
488 
489 u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
490 {
491 	return __of_translate_address(dev, in_addr, "ranges");
492 }
493 EXPORT_SYMBOL(of_translate_address);
494 
495 u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
496 {
497 	return __of_translate_address(dev, in_addr, "dma-ranges");
498 }
499 EXPORT_SYMBOL(of_translate_dma_address);
500 
501 bool of_can_translate_address(struct device_node *dev)
502 {
503 	struct device_node *parent;
504 	struct of_bus *bus;
505 	int na, ns;
506 
507 	parent = of_get_parent(dev);
508 	if (parent == NULL)
509 		return false;
510 
511 	bus = of_match_bus(parent);
512 	bus->count_cells(dev, &na, &ns);
513 
514 	of_node_put(parent);
515 
516 	return OF_CHECK_COUNTS(na, ns);
517 }
518 EXPORT_SYMBOL(of_can_translate_address);
519 
520 const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
521 		    unsigned int *flags)
522 {
523 	const __be32 *prop;
524 	unsigned int psize;
525 	struct device_node *parent;
526 	struct of_bus *bus;
527 	int onesize, i, na, ns;
528 
529 	/* Get parent & match bus type */
530 	parent = of_get_parent(dev);
531 	if (parent == NULL)
532 		return NULL;
533 	bus = of_match_bus(parent);
534 	bus->count_cells(dev, &na, &ns);
535 	of_node_put(parent);
536 	if (!OF_CHECK_ADDR_COUNT(na))
537 		return NULL;
538 
539 	/* Get "reg" or "assigned-addresses" property */
540 	prop = of_get_property(dev, bus->addresses, &psize);
541 	if (prop == NULL)
542 		return NULL;
543 	psize /= 4;
544 
545 	onesize = na + ns;
546 	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
547 		if (i == index) {
548 			if (size)
549 				*size = of_read_number(prop + na, ns);
550 			if (flags)
551 				*flags = bus->get_flags(prop);
552 			return prop;
553 		}
554 	return NULL;
555 }
556 EXPORT_SYMBOL(of_get_address);
557 
558 static int __of_address_to_resource(struct device_node *dev,
559 		const __be32 *addrp, u64 size, unsigned int flags,
560 		const char *name, struct resource *r)
561 {
562 	u64 taddr;
563 
564 	if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
565 		return -EINVAL;
566 	taddr = of_translate_address(dev, addrp);
567 	if (taddr == OF_BAD_ADDR)
568 		return -EINVAL;
569 	memset(r, 0, sizeof(struct resource));
570 	if (flags & IORESOURCE_IO) {
571 		unsigned long port;
572 		port = pci_address_to_pio(taddr);
573 		if (port == (unsigned long)-1)
574 			return -EINVAL;
575 		r->start = port;
576 		r->end = port + size - 1;
577 	} else {
578 		r->start = taddr;
579 		r->end = taddr + size - 1;
580 	}
581 	r->flags = flags;
582 	r->name = name ? name : dev->full_name;
583 
584 	return 0;
585 }
586 
587 /**
588  * of_address_to_resource - Translate device tree address and return as resource
589  *
590  * Note that if your address is a PIO address, the conversion will fail if
591  * the physical address can't be internally converted to an IO token with
592  * pci_address_to_pio(), that is because it's either called to early or it
593  * can't be matched to any host bridge IO space
594  */
595 int of_address_to_resource(struct device_node *dev, int index,
596 			   struct resource *r)
597 {
598 	const __be32	*addrp;
599 	u64		size;
600 	unsigned int	flags;
601 	const char	*name = NULL;
602 
603 	addrp = of_get_address(dev, index, &size, &flags);
604 	if (addrp == NULL)
605 		return -EINVAL;
606 
607 	/* Get optional "reg-names" property to add a name to a resource */
608 	of_property_read_string_index(dev, "reg-names",	index, &name);
609 
610 	return __of_address_to_resource(dev, addrp, size, flags, name, r);
611 }
612 EXPORT_SYMBOL_GPL(of_address_to_resource);
613 
614 struct device_node *of_find_matching_node_by_address(struct device_node *from,
615 					const struct of_device_id *matches,
616 					u64 base_address)
617 {
618 	struct device_node *dn = of_find_matching_node(from, matches);
619 	struct resource res;
620 
621 	while (dn) {
622 		if (of_address_to_resource(dn, 0, &res))
623 			continue;
624 		if (res.start == base_address)
625 			return dn;
626 		dn = of_find_matching_node(dn, matches);
627 	}
628 
629 	return NULL;
630 }
631 
632 
633 /**
634  * of_iomap - Maps the memory mapped IO for a given device_node
635  * @device:	the device whose io range will be mapped
636  * @index:	index of the io range
637  *
638  * Returns a pointer to the mapped memory
639  */
640 void __iomem *of_iomap(struct device_node *np, int index)
641 {
642 	struct resource res;
643 
644 	if (of_address_to_resource(np, index, &res))
645 		return NULL;
646 
647 	return ioremap(res.start, resource_size(&res));
648 }
649 EXPORT_SYMBOL(of_iomap);
650