2 #include <linux/device.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/sizes.h>
9 #include <linux/slab.h>
10 #include <linux/string.h>
12 /* Max address size we deal with */
13 #define OF_MAX_ADDR_CELLS 4
14 #define OF_CHECK_ADDR_COUNT(na) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
15 #define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
17 static struct of_bus *of_match_bus(struct device_node *np);
18 static int __of_address_to_resource(struct device_node *dev,
19 const __be32 *addrp, u64 size, unsigned int flags,
20 const char *name, struct resource *r);
24 static void of_dump_addr(const char *s, const __be32 *addr, int na)
26 printk(KERN_DEBUG "%s", s);
28 printk(" %08x", be32_to_cpu(*(addr++)));
32 static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
35 /* Callbacks for bus specific translators */
38 const char *addresses;
39 int (*match)(struct device_node *parent);
40 void (*count_cells)(struct device_node *child,
41 int *addrc, int *sizec);
42 u64 (*map)(__be32 *addr, const __be32 *range,
43 int na, int ns, int pna);
44 int (*translate)(__be32 *addr, u64 offset, int na);
45 unsigned int (*get_flags)(const __be32 *addr);
49 * Default translator (generic bus)
52 static void of_bus_default_count_cells(struct device_node *dev,
53 int *addrc, int *sizec)
56 *addrc = of_n_addr_cells(dev);
58 *sizec = of_n_size_cells(dev);
61 static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
62 int na, int ns, int pna)
66 cp = of_read_number(range, na);
67 s = of_read_number(range + na + pna, ns);
68 da = of_read_number(addr, na);
70 pr_debug("OF: default map, cp=%llx, s=%llx, da=%llx\n",
71 (unsigned long long)cp, (unsigned long long)s,
72 (unsigned long long)da);
74 if (da < cp || da >= (cp + s))
79 static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
81 u64 a = of_read_number(addr, na);
82 memset(addr, 0, na * 4);
85 addr[na - 2] = cpu_to_be32(a >> 32);
86 addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
91 static unsigned int of_bus_default_get_flags(const __be32 *addr)
93 return IORESOURCE_MEM;
96 #ifdef CONFIG_OF_ADDRESS_PCI
98 * PCI bus specific translator
101 static int of_bus_pci_match(struct device_node *np)
104 * "pciex" is PCI Express
105 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
106 * "ht" is hypertransport
108 return !strcmp(np->type, "pci") || !strcmp(np->type, "pciex") ||
109 !strcmp(np->type, "vci") || !strcmp(np->type, "ht");
112 static void of_bus_pci_count_cells(struct device_node *np,
113 int *addrc, int *sizec)
121 static unsigned int of_bus_pci_get_flags(const __be32 *addr)
123 unsigned int flags = 0;
124 u32 w = be32_to_cpup(addr);
126 switch((w >> 24) & 0x03) {
128 flags |= IORESOURCE_IO;
130 case 0x02: /* 32 bits */
131 case 0x03: /* 64 bits */
132 flags |= IORESOURCE_MEM;
136 flags |= IORESOURCE_PREFETCH;
140 static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
146 af = of_bus_pci_get_flags(addr);
147 rf = of_bus_pci_get_flags(range);
149 /* Check address type match */
150 if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
153 /* Read address values, skipping high cell */
154 cp = of_read_number(range + 1, na - 1);
155 s = of_read_number(range + na + pna, ns);
156 da = of_read_number(addr + 1, na - 1);
158 pr_debug("OF: PCI map, cp=%llx, s=%llx, da=%llx\n",
159 (unsigned long long)cp, (unsigned long long)s,
160 (unsigned long long)da);
162 if (da < cp || da >= (cp + s))
167 static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
169 return of_bus_default_translate(addr + 1, offset, na - 1);
171 #endif /* CONFIG_OF_ADDRESS_PCI */
174 const __be32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
179 struct device_node *parent;
181 int onesize, i, na, ns;
183 /* Get parent & match bus type */
184 parent = of_get_parent(dev);
187 bus = of_match_bus(parent);
188 if (strcmp(bus->name, "pci")) {
192 bus->count_cells(dev, &na, &ns);
194 if (!OF_CHECK_ADDR_COUNT(na))
197 /* Get "reg" or "assigned-addresses" property */
198 prop = of_get_property(dev, bus->addresses, &psize);
204 for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
205 u32 val = be32_to_cpu(prop[0]);
206 if ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
208 *size = of_read_number(prop + na, ns);
210 *flags = bus->get_flags(prop);
216 EXPORT_SYMBOL(of_get_pci_address);
218 int of_pci_address_to_resource(struct device_node *dev, int bar,
225 addrp = of_get_pci_address(dev, bar, &size, &flags);
228 return __of_address_to_resource(dev, addrp, size, flags, NULL, r);
230 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
232 int of_pci_range_parser_init(struct of_pci_range_parser *parser,
233 struct device_node *node)
235 const int na = 3, ns = 2;
239 parser->pna = of_n_addr_cells(node);
240 parser->np = parser->pna + na + ns;
242 parser->range = of_get_property(node, "ranges", &rlen);
243 if (parser->range == NULL)
246 parser->end = parser->range + rlen / sizeof(__be32);
250 EXPORT_SYMBOL_GPL(of_pci_range_parser_init);
252 struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
253 struct of_pci_range *range)
255 const int na = 3, ns = 2;
260 if (!parser->range || parser->range + parser->np > parser->end)
263 range->pci_space = parser->range[0];
264 range->flags = of_bus_pci_get_flags(parser->range);
265 range->pci_addr = of_read_number(parser->range + 1, ns);
266 range->cpu_addr = of_translate_address(parser->node,
268 range->size = of_read_number(parser->range + parser->pna + na, ns);
270 parser->range += parser->np;
272 /* Now consume following elements while they are contiguous */
273 while (parser->range + parser->np <= parser->end) {
274 u32 flags, pci_space;
275 u64 pci_addr, cpu_addr, size;
277 pci_space = be32_to_cpup(parser->range);
278 flags = of_bus_pci_get_flags(parser->range);
279 pci_addr = of_read_number(parser->range + 1, ns);
280 cpu_addr = of_translate_address(parser->node,
282 size = of_read_number(parser->range + parser->pna + na, ns);
284 if (flags != range->flags)
286 if (pci_addr != range->pci_addr + range->size ||
287 cpu_addr != range->cpu_addr + range->size)
291 parser->range += parser->np;
296 EXPORT_SYMBOL_GPL(of_pci_range_parser_one);
299 * of_pci_range_to_resource - Create a resource from an of_pci_range
300 * @range: the PCI range that describes the resource
301 * @np: device node where the range belongs to
302 * @res: pointer to a valid resource that will be updated to
303 * reflect the values contained in the range.
305 * Returns EINVAL if the range cannot be converted to resource.
307 * Note that if the range is an IO range, the resource will be converted
308 * using pci_address_to_pio() which can fail if it is called too early or
309 * if the range cannot be matched to any host bridge IO space (our case here).
310 * To guard against that we try to register the IO range first.
311 * If that fails we know that pci_address_to_pio() will do too.
313 int of_pci_range_to_resource(struct of_pci_range *range,
314 struct device_node *np, struct resource *res)
317 res->flags = range->flags;
318 res->parent = res->child = res->sibling = NULL;
319 res->name = np->full_name;
321 if (res->flags & IORESOURCE_IO) {
323 err = pci_register_io_range(range->cpu_addr, range->size);
326 port = pci_address_to_pio(range->cpu_addr);
327 if (port == (unsigned long)-1) {
333 if ((sizeof(resource_size_t) < 8) &&
334 upper_32_bits(range->cpu_addr)) {
339 res->start = range->cpu_addr;
341 res->end = res->start + range->size - 1;
345 res->start = (resource_size_t)OF_BAD_ADDR;
346 res->end = (resource_size_t)OF_BAD_ADDR;
349 #endif /* CONFIG_PCI */
352 * ISA bus specific translator
355 static int of_bus_isa_match(struct device_node *np)
357 return !strcmp(np->name, "isa");
360 static void of_bus_isa_count_cells(struct device_node *child,
361 int *addrc, int *sizec)
369 static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
374 /* Check address type match */
375 if ((addr[0] ^ range[0]) & cpu_to_be32(1))
378 /* Read address values, skipping high cell */
379 cp = of_read_number(range + 1, na - 1);
380 s = of_read_number(range + na + pna, ns);
381 da = of_read_number(addr + 1, na - 1);
383 pr_debug("OF: ISA map, cp=%llx, s=%llx, da=%llx\n",
384 (unsigned long long)cp, (unsigned long long)s,
385 (unsigned long long)da);
387 if (da < cp || da >= (cp + s))
392 static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
394 return of_bus_default_translate(addr + 1, offset, na - 1);
397 static unsigned int of_bus_isa_get_flags(const __be32 *addr)
399 unsigned int flags = 0;
400 u32 w = be32_to_cpup(addr);
403 flags |= IORESOURCE_IO;
405 flags |= IORESOURCE_MEM;
410 * Array of bus specific translators
413 static struct of_bus of_busses[] = {
414 #ifdef CONFIG_OF_ADDRESS_PCI
418 .addresses = "assigned-addresses",
419 .match = of_bus_pci_match,
420 .count_cells = of_bus_pci_count_cells,
421 .map = of_bus_pci_map,
422 .translate = of_bus_pci_translate,
423 .get_flags = of_bus_pci_get_flags,
425 #endif /* CONFIG_OF_ADDRESS_PCI */
430 .match = of_bus_isa_match,
431 .count_cells = of_bus_isa_count_cells,
432 .map = of_bus_isa_map,
433 .translate = of_bus_isa_translate,
434 .get_flags = of_bus_isa_get_flags,
441 .count_cells = of_bus_default_count_cells,
442 .map = of_bus_default_map,
443 .translate = of_bus_default_translate,
444 .get_flags = of_bus_default_get_flags,
448 static struct of_bus *of_match_bus(struct device_node *np)
452 for (i = 0; i < ARRAY_SIZE(of_busses); i++)
453 if (!of_busses[i].match || of_busses[i].match(np))
454 return &of_busses[i];
459 static int of_empty_ranges_quirk(struct device_node *np)
461 if (IS_ENABLED(CONFIG_PPC)) {
462 /* To save cycles, we cache the result for global "Mac" setting */
463 static int quirk_state = -1;
465 /* PA-SEMI sdc DT bug */
466 if (of_device_is_compatible(np, "1682m-sdc"))
469 /* Make quirk cached */
472 of_machine_is_compatible("Power Macintosh") ||
473 of_machine_is_compatible("MacRISC");
479 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
480 struct of_bus *pbus, __be32 *addr,
481 int na, int ns, int pna, const char *rprop)
483 const __be32 *ranges;
486 u64 offset = OF_BAD_ADDR;
488 /* Normally, an absence of a "ranges" property means we are
489 * crossing a non-translatable boundary, and thus the addresses
490 * below the current not cannot be converted to CPU physical ones.
491 * Unfortunately, while this is very clear in the spec, it's not
492 * what Apple understood, and they do have things like /uni-n or
493 * /ht nodes with no "ranges" property and a lot of perfectly
494 * useable mapped devices below them. Thus we treat the absence of
495 * "ranges" as equivalent to an empty "ranges" property which means
496 * a 1:1 translation at that level. It's up to the caller not to try
497 * to translate addresses that aren't supposed to be translated in
498 * the first place. --BenH.
500 * As far as we know, this damage only exists on Apple machines, so
501 * This code is only enabled on powerpc. --gcl
503 ranges = of_get_property(parent, rprop, &rlen);
504 if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
505 pr_debug("OF: no ranges; cannot translate\n");
508 if (ranges == NULL || rlen == 0) {
509 offset = of_read_number(addr, na);
510 memset(addr, 0, pna * 4);
511 pr_debug("OF: empty ranges; 1:1 translation\n");
515 pr_debug("OF: walking ranges...\n");
517 /* Now walk through the ranges */
519 rone = na + pna + ns;
520 for (; rlen >= rone; rlen -= rone, ranges += rone) {
521 offset = bus->map(addr, ranges, na, ns, pna);
522 if (offset != OF_BAD_ADDR)
525 if (offset == OF_BAD_ADDR) {
526 pr_debug("OF: not found !\n");
529 memcpy(addr, ranges + na, 4 * pna);
532 of_dump_addr("OF: parent translation for:", addr, pna);
533 pr_debug("OF: with offset: %llx\n", (unsigned long long)offset);
535 /* Translate it into parent bus space */
536 return pbus->translate(addr, offset, pna);
540 * Translate an address from the device-tree into a CPU physical address,
541 * this walks up the tree and applies the various bus mappings on the
544 * Note: We consider that crossing any level with #size-cells == 0 to mean
545 * that translation is impossible (that is we are not dealing with a value
546 * that can be mapped to a cpu physical address). This is not really specified
547 * that way, but this is traditionally the way IBM at least do things
549 static u64 __of_translate_address(struct device_node *dev,
550 const __be32 *in_addr, const char *rprop)
552 struct device_node *parent = NULL;
553 struct of_bus *bus, *pbus;
554 __be32 addr[OF_MAX_ADDR_CELLS];
555 int na, ns, pna, pns;
556 u64 result = OF_BAD_ADDR;
558 pr_debug("OF: ** translation for device %s **\n", of_node_full_name(dev));
560 /* Increase refcount at current level */
563 /* Get parent & match bus type */
564 parent = of_get_parent(dev);
567 bus = of_match_bus(parent);
569 /* Count address cells & copy address locally */
570 bus->count_cells(dev, &na, &ns);
571 if (!OF_CHECK_COUNTS(na, ns)) {
572 pr_debug("OF: Bad cell count for %s\n", of_node_full_name(dev));
575 memcpy(addr, in_addr, na * 4);
577 pr_debug("OF: bus is %s (na=%d, ns=%d) on %s\n",
578 bus->name, na, ns, of_node_full_name(parent));
579 of_dump_addr("OF: translating address:", addr, na);
583 /* Switch to parent bus */
586 parent = of_get_parent(dev);
588 /* If root, we have finished */
589 if (parent == NULL) {
590 pr_debug("OF: reached root node\n");
591 result = of_read_number(addr, na);
595 /* Get new parent bus and counts */
596 pbus = of_match_bus(parent);
597 pbus->count_cells(dev, &pna, &pns);
598 if (!OF_CHECK_COUNTS(pna, pns)) {
599 printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
600 of_node_full_name(dev));
604 pr_debug("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
605 pbus->name, pna, pns, of_node_full_name(parent));
607 /* Apply bus translation */
608 if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
611 /* Complete the move up one level */
616 of_dump_addr("OF: one level translation:", addr, na);
625 u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
627 return __of_translate_address(dev, in_addr, "ranges");
629 EXPORT_SYMBOL(of_translate_address);
631 u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
633 return __of_translate_address(dev, in_addr, "dma-ranges");
635 EXPORT_SYMBOL(of_translate_dma_address);
637 const __be32 *of_get_address(struct device_node *dev, int index, u64 *size,
642 struct device_node *parent;
644 int onesize, i, na, ns;
646 /* Get parent & match bus type */
647 parent = of_get_parent(dev);
650 bus = of_match_bus(parent);
651 bus->count_cells(dev, &na, &ns);
653 if (!OF_CHECK_ADDR_COUNT(na))
656 /* Get "reg" or "assigned-addresses" property */
657 prop = of_get_property(dev, bus->addresses, &psize);
663 for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
666 *size = of_read_number(prop + na, ns);
668 *flags = bus->get_flags(prop);
673 EXPORT_SYMBOL(of_get_address);
677 struct list_head list;
679 resource_size_t size;
682 static LIST_HEAD(io_range_list);
683 static DEFINE_SPINLOCK(io_range_lock);
687 * Record the PCI IO range (expressed as CPU physical address + size).
688 * Return a negative value if an error has occured, zero otherwise
690 int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size)
695 struct io_range *range;
696 resource_size_t allocated_size = 0;
698 /* check if the range hasn't been previously recorded */
699 spin_lock(&io_range_lock);
700 list_for_each_entry(range, &io_range_list, list) {
701 if (addr >= range->start && addr + size <= range->start + size) {
702 /* range already registered, bail out */
705 allocated_size += range->size;
708 /* range not registed yet, check for available space */
709 if (allocated_size + size - 1 > IO_SPACE_LIMIT) {
710 /* if it's too big check if 64K space can be reserved */
711 if (allocated_size + SZ_64K - 1 > IO_SPACE_LIMIT) {
717 pr_warn("Requested IO range too big, new size set to 64K\n");
720 /* add the range to the list */
721 range = kzalloc(sizeof(*range), GFP_ATOMIC);
730 list_add_tail(&range->list, &io_range_list);
733 spin_unlock(&io_range_lock);
739 phys_addr_t pci_pio_to_address(unsigned long pio)
741 phys_addr_t address = (phys_addr_t)OF_BAD_ADDR;
744 struct io_range *range;
745 resource_size_t allocated_size = 0;
747 if (pio > IO_SPACE_LIMIT)
750 spin_lock(&io_range_lock);
751 list_for_each_entry(range, &io_range_list, list) {
752 if (pio >= allocated_size && pio < allocated_size + range->size) {
753 address = range->start + pio - allocated_size;
756 allocated_size += range->size;
758 spin_unlock(&io_range_lock);
764 unsigned long __weak pci_address_to_pio(phys_addr_t address)
767 struct io_range *res;
768 resource_size_t offset = 0;
769 unsigned long addr = -1;
771 spin_lock(&io_range_lock);
772 list_for_each_entry(res, &io_range_list, list) {
773 if (address >= res->start && address < res->start + res->size) {
774 addr = address - res->start + offset;
779 spin_unlock(&io_range_lock);
783 if (address > IO_SPACE_LIMIT)
784 return (unsigned long)-1;
786 return (unsigned long) address;
790 static int __of_address_to_resource(struct device_node *dev,
791 const __be32 *addrp, u64 size, unsigned int flags,
792 const char *name, struct resource *r)
796 if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
798 taddr = of_translate_address(dev, addrp);
799 if (taddr == OF_BAD_ADDR)
801 memset(r, 0, sizeof(struct resource));
802 if (flags & IORESOURCE_IO) {
804 port = pci_address_to_pio(taddr);
805 if (port == (unsigned long)-1)
808 r->end = port + size - 1;
811 r->end = taddr + size - 1;
814 r->name = name ? name : dev->full_name;
820 * of_address_to_resource - Translate device tree address and return as resource
822 * Note that if your address is a PIO address, the conversion will fail if
823 * the physical address can't be internally converted to an IO token with
824 * pci_address_to_pio(), that is because it's either called to early or it
825 * can't be matched to any host bridge IO space
827 int of_address_to_resource(struct device_node *dev, int index,
833 const char *name = NULL;
835 addrp = of_get_address(dev, index, &size, &flags);
839 /* Get optional "reg-names" property to add a name to a resource */
840 of_property_read_string_index(dev, "reg-names", index, &name);
842 return __of_address_to_resource(dev, addrp, size, flags, name, r);
844 EXPORT_SYMBOL_GPL(of_address_to_resource);
846 struct device_node *of_find_matching_node_by_address(struct device_node *from,
847 const struct of_device_id *matches,
850 struct device_node *dn = of_find_matching_node(from, matches);
854 if (!of_address_to_resource(dn, 0, &res) &&
855 res.start == base_address)
858 dn = of_find_matching_node(dn, matches);
866 * of_iomap - Maps the memory mapped IO for a given device_node
867 * @device: the device whose io range will be mapped
868 * @index: index of the io range
870 * Returns a pointer to the mapped memory
872 void __iomem *of_iomap(struct device_node *np, int index)
876 if (of_address_to_resource(np, index, &res))
879 return ioremap(res.start, resource_size(&res));
881 EXPORT_SYMBOL(of_iomap);
884 * of_io_request_and_map - Requests a resource and maps the memory mapped IO
885 * for a given device_node
886 * @device: the device whose io range will be mapped
887 * @index: index of the io range
888 * @name: name of the resource
890 * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
891 * error code on failure. Usage example:
893 * base = of_io_request_and_map(node, 0, "foo");
895 * return PTR_ERR(base);
897 void __iomem *of_io_request_and_map(struct device_node *np, int index,
903 if (of_address_to_resource(np, index, &res))
904 return IOMEM_ERR_PTR(-EINVAL);
906 if (!request_mem_region(res.start, resource_size(&res), name))
907 return IOMEM_ERR_PTR(-EBUSY);
909 mem = ioremap(res.start, resource_size(&res));
911 release_mem_region(res.start, resource_size(&res));
912 return IOMEM_ERR_PTR(-ENOMEM);
917 EXPORT_SYMBOL(of_io_request_and_map);
920 * of_dma_get_range - Get DMA range info
921 * @np: device node to get DMA range info
922 * @dma_addr: pointer to store initial DMA address of DMA range
923 * @paddr: pointer to store initial CPU address of DMA range
924 * @size: pointer to store size of DMA range
926 * Look in bottom up direction for the first "dma-ranges" property
929 * DMA addr (dma_addr) : naddr cells
930 * CPU addr (phys_addr_t) : pna cells
933 * It returns -ENODEV if "dma-ranges" property was not found
934 * for this device in DT.
936 int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
938 struct device_node *node = of_node_get(np);
939 const __be32 *ranges = NULL;
940 int len, naddr, nsize, pna;
948 naddr = of_n_addr_cells(node);
949 nsize = of_n_size_cells(node);
950 node = of_get_next_parent(node);
954 ranges = of_get_property(node, "dma-ranges", &len);
956 /* Ignore empty ranges, they imply no translation required */
957 if (ranges && len > 0)
961 * At least empty ranges has to be defined for parent node if
969 pr_debug("%s: no dma-ranges found for node(%s)\n",
970 __func__, np->full_name);
977 pna = of_n_addr_cells(node);
979 /* dma-ranges format:
980 * DMA addr : naddr cells
981 * CPU addr : pna cells
984 dmaaddr = of_read_number(ranges, naddr);
985 *paddr = of_translate_dma_address(np, ranges);
986 if (*paddr == OF_BAD_ADDR) {
987 pr_err("%s: translation of DMA address(%pad) to CPU address failed node(%s)\n",
988 __func__, dma_addr, np->full_name);
994 *size = of_read_number(ranges + naddr + pna, nsize);
996 pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
997 *dma_addr, *paddr, *size);
1004 EXPORT_SYMBOL_GPL(of_dma_get_range);
1007 * of_dma_is_coherent - Check if device is coherent
1010 * It returns true if "dma-coherent" property was found
1011 * for this device in DT.
1013 bool of_dma_is_coherent(struct device_node *np)
1015 struct device_node *node = of_node_get(np);
1018 if (of_property_read_bool(node, "dma-coherent")) {
1022 node = of_get_next_parent(node);
1027 EXPORT_SYMBOL_GPL(of_dma_is_coherent);