xref: /linux/drivers/of/address.c (revision ad1b832bf1cf2df9304f8eb72943111625c7e5a7)
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/overflow.h>
12 #include <linux/pci.h>
13 #include <linux/pci_regs.h>
14 #include <linux/sizes.h>
15 #include <linux/slab.h>
16 #include <linux/string.h>
17 #include <linux/dma-direct.h> /* for bus_dma_region */
18 
19 #include <kunit/visibility.h>
20 
21 /* Uncomment me to enable of_dump_addr() debugging output */
22 // #define DEBUG
23 
24 #include "of_private.h"
25 
26 /* Callbacks for bus specific translators */
27 struct of_bus {
28 	const char	*name;
29 	const char	*addresses;
30 	int		(*match)(struct device_node *parent);
31 	void		(*count_cells)(struct device_node *child,
32 				       int *addrc, int *sizec);
33 	u64		(*map)(__be32 *addr, const __be32 *range,
34 				int na, int ns, int pna, int fna);
35 	int		(*translate)(__be32 *addr, u64 offset, int na);
36 	int		flag_cells;
37 	unsigned int	(*get_flags)(const __be32 *addr);
38 };
39 
40 /*
41  * Default translator (generic bus)
42  */
43 
of_bus_default_count_cells(struct device_node * dev,int * addrc,int * sizec)44 static void of_bus_default_count_cells(struct device_node *dev,
45 				       int *addrc, int *sizec)
46 {
47 	if (addrc)
48 		*addrc = of_n_addr_cells(dev);
49 	if (sizec)
50 		*sizec = of_n_size_cells(dev);
51 }
52 
of_bus_default_map(__be32 * addr,const __be32 * range,int na,int ns,int pna,int fna)53 static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
54 		int na, int ns, int pna, int fna)
55 {
56 	u64 cp, s, da;
57 
58 	cp = of_read_number(range + fna, na - fna);
59 	s  = of_read_number(range + na + pna, ns);
60 	da = of_read_number(addr + fna, na - fna);
61 
62 	pr_debug("default map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);
63 
64 	if (da < cp || da >= (cp + s))
65 		return OF_BAD_ADDR;
66 	return da - cp;
67 }
68 
of_bus_default_translate(__be32 * addr,u64 offset,int na)69 static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
70 {
71 	u64 a = of_read_number(addr, na);
72 	memset(addr, 0, na * 4);
73 	a += offset;
74 	if (na > 1)
75 		addr[na - 2] = cpu_to_be32(a >> 32);
76 	addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
77 
78 	return 0;
79 }
80 
of_bus_default_flags_get_flags(const __be32 * addr)81 static unsigned int of_bus_default_flags_get_flags(const __be32 *addr)
82 {
83 	return of_read_number(addr, 1);
84 }
85 
of_bus_default_get_flags(const __be32 * addr)86 static unsigned int of_bus_default_get_flags(const __be32 *addr)
87 {
88 	return IORESOURCE_MEM;
89 }
90 
of_bus_default_flags_map(__be32 * addr,const __be32 * range,int na,int ns,int pna,int fna)91 static u64 of_bus_default_flags_map(__be32 *addr, const __be32 *range, int na,
92 				    int ns, int pna, int fna)
93 {
94 	/* Check that flags match */
95 	if (*addr != *range)
96 		return OF_BAD_ADDR;
97 
98 	return of_bus_default_map(addr, range, na, ns, pna, fna);
99 }
100 
of_bus_default_flags_translate(__be32 * addr,u64 offset,int na)101 static int of_bus_default_flags_translate(__be32 *addr, u64 offset, int na)
102 {
103 	/* Keep "flags" part (high cell) in translated address */
104 	return of_bus_default_translate(addr + 1, offset, na - 1);
105 }
106 
107 #ifdef CONFIG_PCI
of_bus_pci_get_flags(const __be32 * addr)108 static unsigned int of_bus_pci_get_flags(const __be32 *addr)
109 {
110 	unsigned int flags = 0;
111 	u32 w = be32_to_cpup(addr);
112 
113 	if (!IS_ENABLED(CONFIG_PCI))
114 		return 0;
115 
116 	switch((w >> 24) & 0x03) {
117 	case 0x01:
118 		flags |= IORESOURCE_IO;
119 		break;
120 	case 0x02: /* 32 bits */
121 		flags |= IORESOURCE_MEM;
122 		break;
123 
124 	case 0x03: /* 64 bits */
125 		flags |= IORESOURCE_MEM | IORESOURCE_MEM_64;
126 		break;
127 	}
128 	if (w & 0x40000000)
129 		flags |= IORESOURCE_PREFETCH;
130 	return flags;
131 }
132 
133 /*
134  * PCI bus specific translator
135  */
136 
of_node_is_pcie(const struct device_node * np)137 static bool of_node_is_pcie(const struct device_node *np)
138 {
139 	bool is_pcie = of_node_name_eq(np, "pcie");
140 
141 	if (is_pcie)
142 		pr_warn_once("%pOF: Missing device_type\n", np);
143 
144 	return is_pcie;
145 }
146 
of_bus_pci_match(struct device_node * np)147 static int of_bus_pci_match(struct device_node *np)
148 {
149 	/*
150  	 * "pciex" is PCI Express
151 	 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
152 	 * "ht" is hypertransport
153 	 *
154 	 * If none of the device_type match, and that the node name is
155 	 * "pcie", accept the device as PCI (with a warning).
156 	 */
157 	return of_node_is_type(np, "pci") || of_node_is_type(np, "pciex") ||
158 		of_node_is_type(np, "vci") || of_node_is_type(np, "ht") ||
159 		of_node_is_pcie(np);
160 }
161 
of_bus_pci_count_cells(struct device_node * np,int * addrc,int * sizec)162 static void of_bus_pci_count_cells(struct device_node *np,
163 				   int *addrc, int *sizec)
164 {
165 	if (addrc)
166 		*addrc = 3;
167 	if (sizec)
168 		*sizec = 2;
169 }
170 
of_bus_pci_map(__be32 * addr,const __be32 * range,int na,int ns,int pna,int fna)171 static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
172 		int pna, int fna)
173 {
174 	unsigned int af, rf;
175 
176 	af = of_bus_pci_get_flags(addr);
177 	rf = of_bus_pci_get_flags(range);
178 
179 	/* Check address type match */
180 	if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
181 		return OF_BAD_ADDR;
182 
183 	return of_bus_default_map(addr, range, na, ns, pna, fna);
184 }
185 
186 #endif /* CONFIG_PCI */
187 
__of_address_resource_bounds(struct resource * r,u64 start,u64 size)188 VISIBLE_IF_KUNIT int __of_address_resource_bounds(struct resource *r, u64 start, u64 size)
189 {
190 	if (overflows_type(start, r->start))
191 		return -EOVERFLOW;
192 
193 	r->start = start;
194 
195 	if (!size)
196 		r->end = wrapping_sub(typeof(r->end), r->start, 1);
197 	else if (size && check_add_overflow(r->start, size - 1, &r->end))
198 		return -EOVERFLOW;
199 
200 	return 0;
201 }
202 EXPORT_SYMBOL_IF_KUNIT(__of_address_resource_bounds);
203 
204 /*
205  * of_pci_range_to_resource - Create a resource from an of_pci_range
206  * @range:	the PCI range that describes the resource
207  * @np:		device node where the range belongs to
208  * @res:	pointer to a valid resource that will be updated to
209  *              reflect the values contained in the range.
210  *
211  * Returns -EINVAL if the range cannot be converted to resource.
212  *
213  * Note that if the range is an IO range, the resource will be converted
214  * using pci_address_to_pio() which can fail if it is called too early or
215  * if the range cannot be matched to any host bridge IO space (our case here).
216  * To guard against that we try to register the IO range first.
217  * If that fails we know that pci_address_to_pio() will do too.
218  */
of_pci_range_to_resource(const struct of_pci_range * range,const struct device_node * np,struct resource * res)219 int of_pci_range_to_resource(const struct of_pci_range *range,
220 			     const struct device_node *np, struct resource *res)
221 {
222 	u64 start;
223 	int err;
224 	res->flags = range->flags;
225 	res->parent = res->child = res->sibling = NULL;
226 	res->name = np->full_name;
227 
228 	if (res->flags & IORESOURCE_IO) {
229 		unsigned long port;
230 		err = pci_register_io_range(&np->fwnode, range->cpu_addr,
231 				range->size);
232 		if (err)
233 			goto invalid_range;
234 		port = pci_address_to_pio(range->cpu_addr);
235 		if (port == (unsigned long)-1) {
236 			err = -EINVAL;
237 			goto invalid_range;
238 		}
239 		start = port;
240 	} else {
241 		start = range->cpu_addr;
242 	}
243 	return __of_address_resource_bounds(res, start, range->size);
244 
245 invalid_range:
246 	res->start = (resource_size_t)OF_BAD_ADDR;
247 	res->end = (resource_size_t)OF_BAD_ADDR;
248 	return err;
249 }
250 EXPORT_SYMBOL(of_pci_range_to_resource);
251 
252 /*
253  * of_range_to_resource - Create a resource from a ranges entry
254  * @np:		device node where the range belongs to
255  * @index:	the 'ranges' index to convert to a resource
256  * @res:	pointer to a valid resource that will be updated to
257  *              reflect the values contained in the range.
258  *
259  * Returns -ENOENT if the entry is not found or -EOVERFLOW if the range
260  * cannot be converted to resource.
261  */
of_range_to_resource(struct device_node * np,int index,struct resource * res)262 int of_range_to_resource(struct device_node *np, int index, struct resource *res)
263 {
264 	int ret, i = 0;
265 	struct of_range_parser parser;
266 	struct of_range range;
267 
268 	ret = of_range_parser_init(&parser, np);
269 	if (ret)
270 		return ret;
271 
272 	for_each_of_range(&parser, &range)
273 		if (i++ == index)
274 			return of_pci_range_to_resource(&range, np, res);
275 
276 	return -ENOENT;
277 }
278 EXPORT_SYMBOL(of_range_to_resource);
279 
280 /*
281  * ISA bus specific translator
282  */
283 
of_bus_isa_match(struct device_node * np)284 static int of_bus_isa_match(struct device_node *np)
285 {
286 	return of_node_name_eq(np, "isa");
287 }
288 
of_bus_isa_count_cells(struct device_node * child,int * addrc,int * sizec)289 static void of_bus_isa_count_cells(struct device_node *child,
290 				   int *addrc, int *sizec)
291 {
292 	if (addrc)
293 		*addrc = 2;
294 	if (sizec)
295 		*sizec = 1;
296 }
297 
of_bus_isa_map(__be32 * addr,const __be32 * range,int na,int ns,int pna,int fna)298 static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
299 		int pna, int fna)
300 {
301 	/* Check address type match */
302 	if ((addr[0] ^ range[0]) & cpu_to_be32(1))
303 		return OF_BAD_ADDR;
304 
305 	return of_bus_default_map(addr, range, na, ns, pna, fna);
306 }
307 
of_bus_isa_get_flags(const __be32 * addr)308 static unsigned int of_bus_isa_get_flags(const __be32 *addr)
309 {
310 	unsigned int flags = 0;
311 	u32 w = be32_to_cpup(addr);
312 
313 	if (w & 1)
314 		flags |= IORESOURCE_IO;
315 	else
316 		flags |= IORESOURCE_MEM;
317 	return flags;
318 }
319 
of_bus_default_flags_match(struct device_node * np)320 static int of_bus_default_flags_match(struct device_node *np)
321 {
322 	/*
323 	 * Check for presence first since of_bus_n_addr_cells() will warn when
324 	 * walking parent nodes.
325 	 */
326 	return of_property_present(np, "#address-cells") && (of_bus_n_addr_cells(np) == 3);
327 }
328 
of_bus_default_match(struct device_node * np)329 static int of_bus_default_match(struct device_node *np)
330 {
331 	/*
332 	 * Check for presence first since of_bus_n_addr_cells() will warn when
333 	 * walking parent nodes.
334 	 */
335 	return of_property_present(np, "#address-cells");
336 }
337 
338 /*
339  * Array of bus specific translators
340  */
341 
342 static const struct of_bus of_busses[] = {
343 #ifdef CONFIG_PCI
344 	/* PCI */
345 	{
346 		.name = "pci",
347 		.addresses = "assigned-addresses",
348 		.match = of_bus_pci_match,
349 		.count_cells = of_bus_pci_count_cells,
350 		.map = of_bus_pci_map,
351 		.translate = of_bus_default_flags_translate,
352 		.flag_cells = 1,
353 		.get_flags = of_bus_pci_get_flags,
354 	},
355 #endif /* CONFIG_PCI */
356 	/* ISA */
357 	{
358 		.name = "isa",
359 		.addresses = "reg",
360 		.match = of_bus_isa_match,
361 		.count_cells = of_bus_isa_count_cells,
362 		.map = of_bus_isa_map,
363 		.translate = of_bus_default_flags_translate,
364 		.flag_cells = 1,
365 		.get_flags = of_bus_isa_get_flags,
366 	},
367 	/* Default with flags cell */
368 	{
369 		.name = "default-flags",
370 		.addresses = "reg",
371 		.match = of_bus_default_flags_match,
372 		.count_cells = of_bus_default_count_cells,
373 		.map = of_bus_default_flags_map,
374 		.translate = of_bus_default_flags_translate,
375 		.flag_cells = 1,
376 		.get_flags = of_bus_default_flags_get_flags,
377 	},
378 	/* Default */
379 	{
380 		.name = "default",
381 		.addresses = "reg",
382 		.match = of_bus_default_match,
383 		.count_cells = of_bus_default_count_cells,
384 		.map = of_bus_default_map,
385 		.translate = of_bus_default_translate,
386 		.get_flags = of_bus_default_get_flags,
387 	},
388 };
389 
of_match_bus(struct device_node * np)390 static const struct of_bus *of_match_bus(struct device_node *np)
391 {
392 	int i;
393 
394 	for (i = 0; i < ARRAY_SIZE(of_busses); i++)
395 		if (!of_busses[i].match || of_busses[i].match(np))
396 			return &of_busses[i];
397 	return NULL;
398 }
399 
of_empty_ranges_quirk(const struct device_node * np)400 static int of_empty_ranges_quirk(const struct device_node *np)
401 {
402 	if (IS_ENABLED(CONFIG_PPC)) {
403 		/* To save cycles, we cache the result for global "Mac" setting */
404 		static int quirk_state = -1;
405 
406 		/* PA-SEMI sdc DT bug */
407 		if (of_device_is_compatible(np, "1682m-sdc"))
408 			return true;
409 
410 		/* Make quirk cached */
411 		if (quirk_state < 0)
412 			quirk_state =
413 				of_machine_is_compatible("Power Macintosh") ||
414 				of_machine_is_compatible("MacRISC");
415 		return quirk_state;
416 	}
417 	return false;
418 }
419 
of_translate_one(const struct device_node * parent,const struct of_bus * bus,const struct of_bus * pbus,__be32 * addr,int na,int ns,int pna,const char * rprop)420 static int of_translate_one(const struct device_node *parent, const struct of_bus *bus,
421 			    const struct of_bus *pbus, __be32 *addr,
422 			    int na, int ns, int pna, const char *rprop)
423 {
424 	const __be32 *ranges;
425 	unsigned int rlen;
426 	int rone;
427 	u64 offset = OF_BAD_ADDR;
428 
429 	/*
430 	 * Normally, an absence of a "ranges" property means we are
431 	 * crossing a non-translatable boundary, and thus the addresses
432 	 * below the current cannot be converted to CPU physical ones.
433 	 * Unfortunately, while this is very clear in the spec, it's not
434 	 * what Apple understood, and they do have things like /uni-n or
435 	 * /ht nodes with no "ranges" property and a lot of perfectly
436 	 * useable mapped devices below them. Thus we treat the absence of
437 	 * "ranges" as equivalent to an empty "ranges" property which means
438 	 * a 1:1 translation at that level. It's up to the caller not to try
439 	 * to translate addresses that aren't supposed to be translated in
440 	 * the first place. --BenH.
441 	 *
442 	 * As far as we know, this damage only exists on Apple machines, so
443 	 * This code is only enabled on powerpc. --gcl
444 	 *
445 	 * This quirk also applies for 'dma-ranges' which frequently exist in
446 	 * child nodes without 'dma-ranges' in the parent nodes. --RobH
447 	 */
448 	ranges = of_get_property(parent, rprop, &rlen);
449 	if (ranges == NULL && !of_empty_ranges_quirk(parent) &&
450 	    strcmp(rprop, "dma-ranges")) {
451 		pr_debug("no ranges; cannot translate\n");
452 		return 1;
453 	}
454 	if (ranges == NULL || rlen == 0) {
455 		offset = of_read_number(addr, na);
456 		/* set address to zero, pass flags through */
457 		memset(addr + pbus->flag_cells, 0, (pna - pbus->flag_cells) * 4);
458 		pr_debug("empty ranges; 1:1 translation\n");
459 		goto finish;
460 	}
461 
462 	pr_debug("walking ranges...\n");
463 
464 	/* Now walk through the ranges */
465 	rlen /= 4;
466 	rone = na + pna + ns;
467 	for (; rlen >= rone; rlen -= rone, ranges += rone) {
468 		offset = bus->map(addr, ranges, na, ns, pna, bus->flag_cells);
469 		if (offset != OF_BAD_ADDR)
470 			break;
471 	}
472 	if (offset == OF_BAD_ADDR) {
473 		pr_debug("not found !\n");
474 		return 1;
475 	}
476 	memcpy(addr, ranges + na, 4 * pna);
477 
478  finish:
479 	of_dump_addr("parent translation for:", addr, pna);
480 	pr_debug("with offset: %llx\n", offset);
481 
482 	/* Translate it into parent bus space */
483 	return pbus->translate(addr, offset, pna);
484 }
485 
486 /*
487  * Translate an address from the device-tree into a CPU physical address,
488  * this walks up the tree and applies the various bus mappings on the
489  * way.
490  *
491  * Note: We consider that crossing any level with #size-cells == 0 to mean
492  * that translation is impossible (that is we are not dealing with a value
493  * that can be mapped to a cpu physical address). This is not really specified
494  * that way, but this is traditionally the way IBM at least do things
495  *
496  * Whenever the translation fails, the *host pointer will be set to the
497  * device that had registered logical PIO mapping, and the return code is
498  * relative to that node.
499  */
__of_translate_address(struct device_node * node,struct device_node * (* get_parent)(const struct device_node *),const __be32 * in_addr,const char * rprop,struct device_node ** host)500 static u64 __of_translate_address(struct device_node *node,
501 				  struct device_node *(*get_parent)(const struct device_node *),
502 				  const __be32 *in_addr, const char *rprop,
503 				  struct device_node **host)
504 {
505 	struct device_node *dev __free(device_node) = of_node_get(node);
506 	struct device_node *parent __free(device_node) = get_parent(dev);
507 	const struct of_bus *bus, *pbus;
508 	__be32 addr[OF_MAX_ADDR_CELLS];
509 	int na, ns, pna, pns;
510 
511 	pr_debug("** translation for device %pOF **\n", dev);
512 
513 	*host = NULL;
514 
515 	if (parent == NULL)
516 		return OF_BAD_ADDR;
517 	bus = of_match_bus(parent);
518 	if (!bus)
519 		return OF_BAD_ADDR;
520 
521 	/* Count address cells & copy address locally */
522 	bus->count_cells(dev, &na, &ns);
523 	if (!OF_CHECK_COUNTS(na, ns)) {
524 		pr_debug("Bad cell count for %pOF\n", dev);
525 		return OF_BAD_ADDR;
526 	}
527 	memcpy(addr, in_addr, na * 4);
528 
529 	pr_debug("bus is %s (na=%d, ns=%d) on %pOF\n",
530 	    bus->name, na, ns, parent);
531 	of_dump_addr("translating address:", addr, na);
532 
533 	/* Translate */
534 	for (;;) {
535 		struct logic_pio_hwaddr *iorange;
536 
537 		/* Switch to parent bus */
538 		of_node_put(dev);
539 		dev = parent;
540 		parent = get_parent(dev);
541 
542 		/* If root, we have finished */
543 		if (parent == NULL) {
544 			pr_debug("reached root node\n");
545 			return of_read_number(addr, na);
546 		}
547 
548 		/*
549 		 * For indirectIO device which has no ranges property, get
550 		 * the address from reg directly.
551 		 */
552 		iorange = find_io_range_by_fwnode(&dev->fwnode);
553 		if (iorange && (iorange->flags != LOGIC_PIO_CPU_MMIO)) {
554 			u64 result = of_read_number(addr + 1, na - 1);
555 			pr_debug("indirectIO matched(%pOF) 0x%llx\n",
556 				 dev, result);
557 			*host = no_free_ptr(dev);
558 			return result;
559 		}
560 
561 		/* Get new parent bus and counts */
562 		pbus = of_match_bus(parent);
563 		if (!pbus)
564 			return OF_BAD_ADDR;
565 		pbus->count_cells(dev, &pna, &pns);
566 		if (!OF_CHECK_COUNTS(pna, pns)) {
567 			pr_err("Bad cell count for %pOF\n", dev);
568 			return OF_BAD_ADDR;
569 		}
570 
571 		pr_debug("parent bus is %s (na=%d, ns=%d) on %pOF\n",
572 		    pbus->name, pna, pns, parent);
573 
574 		/* Apply bus translation */
575 		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
576 			return OF_BAD_ADDR;
577 
578 		/* Complete the move up one level */
579 		na = pna;
580 		ns = pns;
581 		bus = pbus;
582 
583 		of_dump_addr("one level translation:", addr, na);
584 	}
585 
586 	unreachable();
587 }
588 
of_translate_address(struct device_node * dev,const __be32 * in_addr)589 u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
590 {
591 	struct device_node *host;
592 	u64 ret;
593 
594 	ret = __of_translate_address(dev, of_get_parent,
595 				     in_addr, "ranges", &host);
596 	if (host) {
597 		of_node_put(host);
598 		return OF_BAD_ADDR;
599 	}
600 
601 	return ret;
602 }
603 EXPORT_SYMBOL(of_translate_address);
604 
605 #ifdef CONFIG_HAS_DMA
__of_get_dma_parent(const struct device_node * np)606 struct device_node *__of_get_dma_parent(const struct device_node *np)
607 {
608 	struct of_phandle_args args;
609 	int ret, index;
610 
611 	index = of_property_match_string(np, "interconnect-names", "dma-mem");
612 	if (index < 0)
613 		return of_get_parent(np);
614 
615 	ret = of_parse_phandle_with_args(np, "interconnects",
616 					 "#interconnect-cells",
617 					 index, &args);
618 	if (ret < 0)
619 		return of_get_parent(np);
620 
621 	return args.np;
622 }
623 #endif
624 
of_get_next_dma_parent(struct device_node * np)625 static struct device_node *of_get_next_dma_parent(struct device_node *np)
626 {
627 	struct device_node *parent;
628 
629 	parent = __of_get_dma_parent(np);
630 	of_node_put(np);
631 
632 	return parent;
633 }
634 
of_translate_dma_address(struct device_node * dev,const __be32 * in_addr)635 u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
636 {
637 	struct device_node *host;
638 	u64 ret;
639 
640 	ret = __of_translate_address(dev, __of_get_dma_parent,
641 				     in_addr, "dma-ranges", &host);
642 
643 	if (host) {
644 		of_node_put(host);
645 		return OF_BAD_ADDR;
646 	}
647 
648 	return ret;
649 }
650 EXPORT_SYMBOL(of_translate_dma_address);
651 
652 /**
653  * of_translate_dma_region - Translate device tree address and size tuple
654  * @dev: device tree node for which to translate
655  * @prop: pointer into array of cells
656  * @start: return value for the start of the DMA range
657  * @length: return value for the length of the DMA range
658  *
659  * Returns a pointer to the cell immediately following the translated DMA region.
660  */
of_translate_dma_region(struct device_node * dev,const __be32 * prop,phys_addr_t * start,size_t * length)661 const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *prop,
662 				      phys_addr_t *start, size_t *length)
663 {
664 	struct device_node *parent __free(device_node) = __of_get_dma_parent(dev);
665 	u64 address, size;
666 	int na, ns;
667 
668 	if (!parent)
669 		return NULL;
670 
671 	na = of_bus_n_addr_cells(parent);
672 	ns = of_bus_n_size_cells(parent);
673 
674 	address = of_translate_dma_address(dev, prop);
675 	if (address == OF_BAD_ADDR)
676 		return NULL;
677 
678 	size = of_read_number(prop + na, ns);
679 
680 	if (start)
681 		*start = address;
682 
683 	if (length)
684 		*length = size;
685 
686 	return prop + na + ns;
687 }
688 EXPORT_SYMBOL(of_translate_dma_region);
689 
__of_get_address(struct device_node * dev,int index,int bar_no,u64 * size,unsigned int * flags)690 const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no,
691 			       u64 *size, unsigned int *flags)
692 {
693 	const __be32 *prop;
694 	unsigned int psize;
695 	struct device_node *parent __free(device_node) = of_get_parent(dev);
696 	const struct of_bus *bus;
697 	int onesize, i, na, ns;
698 
699 	if (parent == NULL)
700 		return NULL;
701 
702 	/* match the parent's bus type */
703 	bus = of_match_bus(parent);
704 	if (!bus || (strcmp(bus->name, "pci") && (bar_no >= 0)))
705 		return NULL;
706 
707 	/* Get "reg" or "assigned-addresses" property */
708 	prop = of_get_property(dev, bus->addresses, &psize);
709 	if (prop == NULL)
710 		return NULL;
711 	psize /= 4;
712 
713 	bus->count_cells(dev, &na, &ns);
714 	if (!OF_CHECK_ADDR_COUNT(na))
715 		return NULL;
716 
717 	onesize = na + ns;
718 	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
719 		u32 val = be32_to_cpu(prop[0]);
720 		/* PCI bus matches on BAR number instead of index */
721 		if (((bar_no >= 0) && ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0))) ||
722 		    ((index >= 0) && (i == index))) {
723 			if (size)
724 				*size = of_read_number(prop + na, ns);
725 			if (flags)
726 				*flags = bus->get_flags(prop);
727 			return prop;
728 		}
729 	}
730 	return NULL;
731 }
732 EXPORT_SYMBOL(__of_get_address);
733 
734 /**
735  * of_property_read_reg - Retrieve the specified "reg" entry index without translating
736  * @np: device tree node for which to retrieve "reg" from
737  * @idx: "reg" entry index to read
738  * @addr: return value for the untranslated address
739  * @size: return value for the entry size
740  *
741  * Returns -EINVAL if "reg" is not found. Returns 0 on success with addr and
742  * size values filled in.
743  */
of_property_read_reg(struct device_node * np,int idx,u64 * addr,u64 * size)744 int of_property_read_reg(struct device_node *np, int idx, u64 *addr, u64 *size)
745 {
746 	const __be32 *prop = of_get_address(np, idx, size, NULL);
747 
748 	if (!prop)
749 		return -EINVAL;
750 
751 	*addr = of_read_number(prop, of_n_addr_cells(np));
752 
753 	return 0;
754 }
755 EXPORT_SYMBOL(of_property_read_reg);
756 
parser_init(struct of_pci_range_parser * parser,struct device_node * node,const char * name)757 static int parser_init(struct of_pci_range_parser *parser,
758 			struct device_node *node, const char *name)
759 {
760 	int rlen;
761 
762 	parser->node = node;
763 	parser->pna = of_n_addr_cells(node);
764 	parser->na = of_bus_n_addr_cells(node);
765 	parser->ns = of_bus_n_size_cells(node);
766 	parser->dma = !strcmp(name, "dma-ranges");
767 	parser->bus = of_match_bus(node);
768 
769 	parser->range = of_get_property(node, name, &rlen);
770 	if (parser->range == NULL)
771 		return -ENOENT;
772 
773 	parser->end = parser->range + rlen / sizeof(__be32);
774 
775 	return 0;
776 }
777 
of_pci_range_parser_init(struct of_pci_range_parser * parser,struct device_node * node)778 int of_pci_range_parser_init(struct of_pci_range_parser *parser,
779 				struct device_node *node)
780 {
781 	return parser_init(parser, node, "ranges");
782 }
783 EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
784 
of_pci_dma_range_parser_init(struct of_pci_range_parser * parser,struct device_node * node)785 int of_pci_dma_range_parser_init(struct of_pci_range_parser *parser,
786 				struct device_node *node)
787 {
788 	return parser_init(parser, node, "dma-ranges");
789 }
790 EXPORT_SYMBOL_GPL(of_pci_dma_range_parser_init);
791 #define of_dma_range_parser_init of_pci_dma_range_parser_init
792 
of_pci_range_parser_one(struct of_pci_range_parser * parser,struct of_pci_range * range)793 struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
794 						struct of_pci_range *range)
795 {
796 	int na = parser->na;
797 	int ns = parser->ns;
798 	int np = parser->pna + na + ns;
799 	int busflag_na = parser->bus->flag_cells;
800 
801 	if (!range)
802 		return NULL;
803 
804 	if (!parser->range || parser->range + np > parser->end)
805 		return NULL;
806 
807 	range->flags = parser->bus->get_flags(parser->range);
808 
809 	range->bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);
810 
811 	if (parser->dma)
812 		range->cpu_addr = of_translate_dma_address(parser->node,
813 				parser->range + na);
814 	else
815 		range->cpu_addr = of_translate_address(parser->node,
816 				parser->range + na);
817 
818 	range->parent_bus_addr = of_read_number(parser->range + na, parser->pna);
819 	range->size = of_read_number(parser->range + parser->pna + na, ns);
820 
821 	parser->range += np;
822 
823 	/* Now consume following elements while they are contiguous */
824 	while (parser->range + np <= parser->end) {
825 		u32 flags = 0;
826 		u64 bus_addr, cpu_addr, size;
827 
828 		flags = parser->bus->get_flags(parser->range);
829 		bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);
830 		if (parser->dma)
831 			cpu_addr = of_translate_dma_address(parser->node,
832 					parser->range + na);
833 		else
834 			cpu_addr = of_translate_address(parser->node,
835 					parser->range + na);
836 		size = of_read_number(parser->range + parser->pna + na, ns);
837 
838 		if (flags != range->flags)
839 			break;
840 		if (bus_addr != range->bus_addr + range->size ||
841 		    cpu_addr != range->cpu_addr + range->size)
842 			break;
843 
844 		range->size += size;
845 		parser->range += np;
846 	}
847 
848 	return range;
849 }
850 EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
851 
of_translate_ioport(struct device_node * dev,const __be32 * in_addr,u64 size)852 static u64 of_translate_ioport(struct device_node *dev, const __be32 *in_addr,
853 			u64 size)
854 {
855 	u64 taddr;
856 	unsigned long port;
857 	struct device_node *host;
858 
859 	taddr = __of_translate_address(dev, of_get_parent,
860 				       in_addr, "ranges", &host);
861 	if (host) {
862 		/* host-specific port access */
863 		port = logic_pio_trans_hwaddr(&host->fwnode, taddr, size);
864 		of_node_put(host);
865 	} else {
866 		/* memory-mapped I/O range */
867 		port = pci_address_to_pio(taddr);
868 	}
869 
870 	if (port == (unsigned long)-1)
871 		return OF_BAD_ADDR;
872 
873 	return port;
874 }
875 
876 #ifdef CONFIG_HAS_DMA
877 /**
878  * of_dma_get_range - Get DMA range info and put it into a map array
879  * @np:		device node to get DMA range info
880  * @map:	dma range structure to return
881  *
882  * Look in bottom up direction for the first "dma-ranges" property
883  * and parse it.  Put the information into a DMA offset map array.
884  *
885  * dma-ranges format:
886  *	DMA addr (dma_addr)	: naddr cells
887  *	CPU addr (phys_addr_t)	: pna cells
888  *	size			: nsize cells
889  *
890  * It returns -ENODEV if "dma-ranges" property was not found for this
891  * device in the DT.
892  */
of_dma_get_range(struct device_node * np,const struct bus_dma_region ** map)893 int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
894 {
895 	struct device_node *node __free(device_node) = of_node_get(np);
896 	const __be32 *ranges = NULL;
897 	bool found_dma_ranges = false;
898 	struct of_range_parser parser;
899 	struct of_range range;
900 	struct bus_dma_region *r;
901 	int len, num_ranges = 0;
902 
903 	while (node) {
904 		ranges = of_get_property(node, "dma-ranges", &len);
905 
906 		/* Ignore empty ranges, they imply no translation required */
907 		if (ranges && len > 0)
908 			break;
909 
910 		/* Once we find 'dma-ranges', then a missing one is an error */
911 		if (found_dma_ranges && !ranges)
912 			return -ENODEV;
913 
914 		found_dma_ranges = true;
915 
916 		node = of_get_next_dma_parent(node);
917 	}
918 
919 	if (!node || !ranges) {
920 		pr_debug("no dma-ranges found for node(%pOF)\n", np);
921 		return -ENODEV;
922 	}
923 	of_dma_range_parser_init(&parser, node);
924 	for_each_of_range(&parser, &range) {
925 		if (range.cpu_addr == OF_BAD_ADDR) {
926 			pr_err("translation of DMA address(%llx) to CPU address failed node(%pOF)\n",
927 			       range.bus_addr, node);
928 			continue;
929 		}
930 		num_ranges++;
931 	}
932 
933 	if (!num_ranges)
934 		return -EINVAL;
935 
936 	r = kcalloc(num_ranges + 1, sizeof(*r), GFP_KERNEL);
937 	if (!r)
938 		return -ENOMEM;
939 
940 	/*
941 	 * Record all info in the generic DMA ranges array for struct device,
942 	 * returning an error if we don't find any parsable ranges.
943 	 */
944 	*map = r;
945 	of_dma_range_parser_init(&parser, node);
946 	for_each_of_range(&parser, &range) {
947 		pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
948 			 range.bus_addr, range.cpu_addr, range.size);
949 		if (range.cpu_addr == OF_BAD_ADDR)
950 			continue;
951 		r->cpu_start = range.cpu_addr;
952 		r->dma_start = range.bus_addr;
953 		r->size = range.size;
954 		r++;
955 	}
956 	return 0;
957 }
958 #endif /* CONFIG_HAS_DMA */
959 
960 /**
961  * of_dma_get_max_cpu_address - Gets highest CPU address suitable for DMA
962  * @np: The node to start searching from or NULL to start from the root
963  *
964  * Gets the highest CPU physical address that is addressable by all DMA masters
965  * in the sub-tree pointed by np, or the whole tree if NULL is passed. If no
966  * DMA constrained device is found, it returns PHYS_ADDR_MAX.
967  */
of_dma_get_max_cpu_address(struct device_node * np)968 phys_addr_t __init of_dma_get_max_cpu_address(struct device_node *np)
969 {
970 	phys_addr_t max_cpu_addr = PHYS_ADDR_MAX;
971 	struct of_range_parser parser;
972 	phys_addr_t subtree_max_addr;
973 	struct device_node *child;
974 	struct of_range range;
975 	const __be32 *ranges;
976 	u64 cpu_end = 0;
977 	int len;
978 
979 	if (!np)
980 		np = of_root;
981 
982 	ranges = of_get_property(np, "dma-ranges", &len);
983 	if (ranges && len) {
984 		of_dma_range_parser_init(&parser, np);
985 		for_each_of_range(&parser, &range)
986 			if (range.cpu_addr + range.size > cpu_end)
987 				cpu_end = range.cpu_addr + range.size - 1;
988 
989 		if (max_cpu_addr > cpu_end)
990 			max_cpu_addr = cpu_end;
991 	}
992 
993 	for_each_available_child_of_node(np, child) {
994 		subtree_max_addr = of_dma_get_max_cpu_address(child);
995 		if (max_cpu_addr > subtree_max_addr)
996 			max_cpu_addr = subtree_max_addr;
997 	}
998 
999 	return max_cpu_addr;
1000 }
1001 
1002 /**
1003  * of_dma_is_coherent - Check if device is coherent
1004  * @np:	device node
1005  *
1006  * It returns true if "dma-coherent" property was found
1007  * for this device in the DT, or if DMA is coherent by
1008  * default for OF devices on the current platform and no
1009  * "dma-noncoherent" property was found for this device.
1010  */
of_dma_is_coherent(struct device_node * np)1011 bool of_dma_is_coherent(struct device_node *np)
1012 {
1013 	struct device_node *node __free(device_node) = of_node_get(np);
1014 
1015 	while (node) {
1016 		if (of_property_read_bool(node, "dma-coherent"))
1017 			return true;
1018 
1019 		if (of_property_read_bool(node, "dma-noncoherent"))
1020 			return false;
1021 
1022 		node = of_get_next_dma_parent(node);
1023 	}
1024 	return dma_default_coherent;
1025 }
1026 EXPORT_SYMBOL_GPL(of_dma_is_coherent);
1027 
1028 /**
1029  * of_mmio_is_nonposted - Check if device uses non-posted MMIO
1030  * @np:	device node
1031  *
1032  * Returns true if the "nonposted-mmio" property was found for
1033  * the device's bus.
1034  *
1035  * This is currently only enabled on builds that support Apple ARM devices, as
1036  * an optimization.
1037  */
of_mmio_is_nonposted(const struct device_node * np)1038 static bool of_mmio_is_nonposted(const struct device_node *np)
1039 {
1040 	if (!IS_ENABLED(CONFIG_ARCH_APPLE))
1041 		return false;
1042 
1043 	struct device_node *parent __free(device_node) = of_get_parent(np);
1044 	if (!parent)
1045 		return false;
1046 
1047 	return of_property_read_bool(parent, "nonposted-mmio");
1048 }
1049 
__of_address_to_resource(struct device_node * dev,int index,int bar_no,struct resource * r)1050 static int __of_address_to_resource(struct device_node *dev, int index, int bar_no,
1051 		struct resource *r)
1052 {
1053 	u64 taddr;
1054 	const __be32	*addrp;
1055 	u64		size;
1056 	unsigned int	flags;
1057 	const char	*name = NULL;
1058 
1059 	addrp = __of_get_address(dev, index, bar_no, &size, &flags);
1060 	if (addrp == NULL)
1061 		return -EINVAL;
1062 
1063 	/* Get optional "reg-names" property to add a name to a resource */
1064 	if (index >= 0)
1065 		of_property_read_string_index(dev, "reg-names",	index, &name);
1066 
1067 	if (flags & IORESOURCE_MEM)
1068 		taddr = of_translate_address(dev, addrp);
1069 	else if (flags & IORESOURCE_IO)
1070 		taddr = of_translate_ioport(dev, addrp, size);
1071 	else
1072 		return -EINVAL;
1073 
1074 	if (taddr == OF_BAD_ADDR)
1075 		return -EINVAL;
1076 	memset(r, 0, sizeof(struct resource));
1077 
1078 	if (of_mmio_is_nonposted(dev))
1079 		flags |= IORESOURCE_MEM_NONPOSTED;
1080 
1081 	r->flags = flags;
1082 	r->name = name ? name : dev->full_name;
1083 
1084 	return __of_address_resource_bounds(r, taddr, size);
1085 }
1086 
1087 /**
1088  * of_address_to_resource - Translate device tree address and return as resource
1089  * @dev:	Caller's Device Node
1090  * @index:	Index into the array
1091  * @r:		Pointer to resource array
1092  *
1093  * Returns -EINVAL if the range cannot be converted to resource.
1094  *
1095  * Note that if your address is a PIO address, the conversion will fail if
1096  * the physical address can't be internally converted to an IO token with
1097  * pci_address_to_pio(), that is because it's either called too early or it
1098  * can't be matched to any host bridge IO space
1099  */
of_address_to_resource(struct device_node * dev,int index,struct resource * r)1100 int of_address_to_resource(struct device_node *dev, int index,
1101 			   struct resource *r)
1102 {
1103 	return __of_address_to_resource(dev, index, -1, r);
1104 }
1105 EXPORT_SYMBOL_GPL(of_address_to_resource);
1106 
of_pci_address_to_resource(struct device_node * dev,int bar,struct resource * r)1107 int of_pci_address_to_resource(struct device_node *dev, int bar,
1108 			       struct resource *r)
1109 {
1110 
1111 	if (!IS_ENABLED(CONFIG_PCI))
1112 		return -ENOSYS;
1113 
1114 	return __of_address_to_resource(dev, -1, bar, r);
1115 }
1116 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
1117 
1118 /**
1119  * of_iomap - Maps the memory mapped IO for a given device_node
1120  * @np:		the device whose io range will be mapped
1121  * @index:	index of the io range
1122  *
1123  * Returns a pointer to the mapped memory
1124  */
of_iomap(struct device_node * np,int index)1125 void __iomem *of_iomap(struct device_node *np, int index)
1126 {
1127 	struct resource res;
1128 
1129 	if (of_address_to_resource(np, index, &res))
1130 		return NULL;
1131 
1132 	if (res.flags & IORESOURCE_MEM_NONPOSTED)
1133 		return ioremap_np(res.start, resource_size(&res));
1134 	else
1135 		return ioremap(res.start, resource_size(&res));
1136 }
1137 EXPORT_SYMBOL(of_iomap);
1138 
1139 /*
1140  * of_io_request_and_map - Requests a resource and maps the memory mapped IO
1141  *			   for a given device_node
1142  * @device:	the device whose io range will be mapped
1143  * @index:	index of the io range
1144  * @name:	name "override" for the memory region request or NULL
1145  *
1146  * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
1147  * error code on failure. Usage example:
1148  *
1149  *	base = of_io_request_and_map(node, 0, "foo");
1150  *	if (IS_ERR(base))
1151  *		return PTR_ERR(base);
1152  */
of_io_request_and_map(struct device_node * np,int index,const char * name)1153 void __iomem *of_io_request_and_map(struct device_node *np, int index,
1154 				    const char *name)
1155 {
1156 	struct resource res;
1157 	void __iomem *mem;
1158 
1159 	if (of_address_to_resource(np, index, &res))
1160 		return IOMEM_ERR_PTR(-EINVAL);
1161 
1162 	if (!name)
1163 		name = res.name;
1164 	if (!request_mem_region(res.start, resource_size(&res), name))
1165 		return IOMEM_ERR_PTR(-EBUSY);
1166 
1167 	if (res.flags & IORESOURCE_MEM_NONPOSTED)
1168 		mem = ioremap_np(res.start, resource_size(&res));
1169 	else
1170 		mem = ioremap(res.start, resource_size(&res));
1171 
1172 	if (!mem) {
1173 		release_mem_region(res.start, resource_size(&res));
1174 		return IOMEM_ERR_PTR(-ENOMEM);
1175 	}
1176 
1177 	return mem;
1178 }
1179 EXPORT_SYMBOL(of_io_request_and_map);
1180