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