summaryrefslogtreecommitdiff
path: root/drivers/of/address.c
blob: e692809ff822790b7cf43e43a1d0f3d2c71976bb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
// SPDX-License-Identifier: GPL-2.0
#define pr_fmt(fmt)	"OF: " fmt

#include <linux/device.h>
#include <linux/fwnode.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/logic_pio.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/pci.h>
#include <linux/pci_regs.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/dma-direct.h> /* for bus_dma_region */

#include "of_private.h"

/* Max address size we deal with */
#define OF_MAX_ADDR_CELLS	4
#define OF_CHECK_ADDR_COUNT(na)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
#define OF_CHECK_COUNTS(na, ns)	(OF_CHECK_ADDR_COUNT(na) && (ns) > 0)

/* Debug utility */
#ifdef DEBUG
static void of_dump_addr(const char *s, const __be32 *addr, int na)
{
	pr_debug("%s", s);
	while (na--)
		pr_cont(" %08x", be32_to_cpu(*(addr++)));
	pr_cont("\n");
}
#else
static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
#endif

/* Callbacks for bus specific translators */
struct of_bus {
	const char	*name;
	const char	*addresses;
	int		(*match)(struct device_node *parent);
	void		(*count_cells)(struct device_node *child,
				       int *addrc, int *sizec);
	u64		(*map)(__be32 *addr, const __be32 *range,
				int na, int ns, int pna);
	int		(*translate)(__be32 *addr, u64 offset, int na);
	bool	has_flags;
	unsigned int	(*get_flags)(const __be32 *addr);
};

/*
 * Default translator (generic bus)
 */

static void of_bus_default_count_cells(struct device_node *dev,
				       int *addrc, int *sizec)
{
	if (addrc)
		*addrc = of_n_addr_cells(dev);
	if (sizec)
		*sizec = of_n_size_cells(dev);
}

static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
		int na, int ns, int pna)
{
	u64 cp, s, da;

	cp = of_read_number(range, na);
	s  = of_read_number(range + na + pna, ns);
	da = of_read_number(addr, na);

	pr_debug("default map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);

	if (da < cp || da >= (cp + s))
		return OF_BAD_ADDR;
	return da - cp;
}

static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
{
	u64 a = of_read_number(addr, na);
	memset(addr, 0, na * 4);
	a += offset;
	if (na > 1)
		addr[na - 2] = cpu_to_be32(a >> 32);
	addr[na - 1] = cpu_to_be32(a & 0xffffffffu);

	return 0;
}

static unsigned int of_bus_default_flags_get_flags(const __be32 *addr)
{
	return of_read_number(addr, 1);
}

static unsigned int of_bus_default_get_flags(const __be32 *addr)
{
	return IORESOURCE_MEM;
}


#ifdef CONFIG_PCI
static unsigned int of_bus_pci_get_flags(const __be32 *addr)
{
	unsigned int flags = 0;
	u32 w = be32_to_cpup(addr);

	if (!IS_ENABLED(CONFIG_PCI))
		return 0;

	switch((w >> 24) & 0x03) {
	case 0x01:
		flags |= IORESOURCE_IO;
		break;
	case 0x02: /* 32 bits */
		flags |= IORESOURCE_MEM;
		break;

	case 0x03: /* 64 bits */
		flags |= IORESOURCE_MEM | IORESOURCE_MEM_64;
		break;
	}
	if (w & 0x40000000)
		flags |= IORESOURCE_PREFETCH;
	return flags;
}

/*
 * PCI bus specific translator
 */

static bool of_node_is_pcie(struct device_node *np)
{
	bool is_pcie = of_node_name_eq(np, "pcie");

	if (is_pcie)
		pr_warn_once("%pOF: Missing device_type\n", np);

	return is_pcie;
}

static int of_bus_pci_match(struct device_node *np)
{
	/*
 	 * "pciex" is PCI Express
	 * "vci" is for the /chaos bridge on 1st-gen PCI powermacs
	 * "ht" is hypertransport
	 *
	 * If none of the device_type match, and that the node name is
	 * "pcie", accept the device as PCI (with a warning).
	 */
	return of_node_is_type(np, "pci") || of_node_is_type(np, "pciex") ||
		of_node_is_type(np, "vci") || of_node_is_type(np, "ht") ||
		of_node_is_pcie(np);
}

static void of_bus_pci_count_cells(struct device_node *np,
				   int *addrc, int *sizec)
{
	if (addrc)
		*addrc = 3;
	if (sizec)
		*sizec = 2;
}

static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns,
		int pna)
{
	u64 cp, s, da;
	unsigned int af, rf;

	af = of_bus_pci_get_flags(addr);
	rf = of_bus_pci_get_flags(range);

	/* Check address type match */
	if ((af ^ rf) & (IORESOURCE_MEM | IORESOURCE_IO))
		return OF_BAD_ADDR;

	/* Read address values, skipping high cell */
	cp = of_read_number(range + 1, na - 1);
	s  = of_read_number(range + na + pna, ns);
	da = of_read_number(addr + 1, na - 1);

	pr_debug("PCI map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);

	if (da < cp || da >= (cp + s))
		return OF_BAD_ADDR;
	return da - cp;
}

static int of_bus_pci_translate(__be32 *addr, u64 offset, int na)
{
	return of_bus_default_translate(addr + 1, offset, na - 1);
}
#endif /* CONFIG_PCI */

/*
 * of_pci_range_to_resource - Create a resource from an of_pci_range
 * @range:	the PCI range that describes the resource
 * @np:		device node where the range belongs to
 * @res:	pointer to a valid resource that will be updated to
 *              reflect the values contained in the range.
 *
 * Returns -EINVAL if the range cannot be converted to resource.
 *
 * Note that if the range is an IO range, the resource will be converted
 * using pci_address_to_pio() which can fail if it is called too early or
 * if the range cannot be matched to any host bridge IO space (our case here).
 * To guard against that we try to register the IO range first.
 * If that fails we know that pci_address_to_pio() will do too.
 */
int of_pci_range_to_resource(struct of_pci_range *range,
			     struct device_node *np, struct resource *res)
{
	int err;
	res->flags = range->flags;
	res->parent = res->child = res->sibling = NULL;
	res->name = np->full_name;

	if (res->flags & IORESOURCE_IO) {
		unsigned long port;
		err = pci_register_io_range(&np->fwnode, range->cpu_addr,
				range->size);
		if (err)
			goto invalid_range;
		port = pci_address_to_pio(range->cpu_addr);
		if (port == (unsigned long)-1) {
			err = -EINVAL;
			goto invalid_range;
		}
		res->start = port;
	} else {
		if ((sizeof(resource_size_t) < 8) &&
		    upper_32_bits(range->cpu_addr)) {
			err = -EINVAL;
			goto invalid_range;
		}

		res->start = range->cpu_addr;
	}
	res->end = res->start + range->size - 1;
	return 0;

invalid_range:
	res->start = (resource_size_t)OF_BAD_ADDR;
	res->end = (resource_size_t)OF_BAD_ADDR;
	return err;
}
EXPORT_SYMBOL(of_pci_range_to_resource);

/*
 * of_range_to_resource - Create a resource from a ranges entry
 * @np:		device node where the range belongs to
 * @index:	the 'ranges' index to convert to a resource
 * @res:	pointer to a valid resource that will be updated to
 *              reflect the values contained in the range.
 *
 * Returns ENOENT if the entry is not found or EINVAL if the range cannot be
 * converted to resource.
 */
int of_range_to_resource(struct device_node *np, int index, struct resource *res)
{
	int ret, i = 0;
	struct of_range_parser parser;
	struct of_range range;

	ret = of_range_parser_init(&parser, np);
	if (ret)
		return ret;

	for_each_of_range(&parser, &range)
		if (i++ == index)
			return of_pci_range_to_resource(&range, np, res);

	return -ENOENT;
}
EXPORT_SYMBOL(of_range_to_resource);

/*
 * ISA bus specific translator
 */

static int of_bus_isa_match(struct device_node *np)
{
	return of_node_name_eq(np, "isa");
}

static void of_bus_isa_count_cells(struct device_node *child,
				   int *addrc, int *sizec)
{
	if (addrc)
		*addrc = 2;
	if (sizec)
		*sizec = 1;
}

static u64 of_bus_isa_map(__be32 *addr, const __be32 *range, int na, int ns,
		int pna)
{
	u64 cp, s, da;

	/* Check address type match */
	if ((addr[0] ^ range[0]) & cpu_to_be32(1))
		return OF_BAD_ADDR;

	/* Read address values, skipping high cell */
	cp = of_read_number(range + 1, na - 1);
	s  = of_read_number(range + na + pna, ns);
	da = of_read_number(addr + 1, na - 1);

	pr_debug("ISA map, cp=%llx, s=%llx, da=%llx\n", cp, s, da);

	if (da < cp || da >= (cp + s))
		return OF_BAD_ADDR;
	return da - cp;
}

static int of_bus_isa_translate(__be32 *addr, u64 offset, int na)
{
	return of_bus_default_translate(addr + 1, offset, na - 1);
}

static unsigned int of_bus_isa_get_flags(const __be32 *addr)
{
	unsigned int flags = 0;
	u32 w = be32_to_cpup(addr);

	if (w & 1)
		flags |= IORESOURCE_IO;
	else
		flags |= IORESOURCE_MEM;
	return flags;
}

static int of_bus_default_flags_match(struct device_node *np)
{
	return of_bus_n_addr_cells(np) == 3;
}

/*
 * Array of bus specific translators
 */

static struct of_bus of_busses[] = {
#ifdef CONFIG_PCI
	/* PCI */
	{
		.name = "pci",
		.addresses = "assigned-addresses",
		.match = of_bus_pci_match,
		.count_cells = of_bus_pci_count_cells,
		.map = of_bus_pci_map,
		.translate = of_bus_pci_translate,
		.has_flags = true,
		.get_flags = of_bus_pci_get_flags,
	},
#endif /* CONFIG_PCI */
	/* ISA */
	{
		.name = "isa",
		.addresses = "reg",
		.match = of_bus_isa_match,
		.count_cells = of_bus_isa_count_cells,
		.map = of_bus_isa_map,
		.translate = of_bus_isa_translate,
		.has_flags = true,
		.get_flags = of_bus_isa_get_flags,
	},
	/* Default with flags cell */
	{
		.name = "default-flags",
		.addresses = "reg",
		.match = of_bus_default_flags_match,
		.count_cells = of_bus_default_count_cells,
		.map = of_bus_default_map,
		.translate = of_bus_default_translate,
		.has_flags = true,
		.get_flags = of_bus_default_flags_get_flags,
	},
	/* Default */
	{
		.name = "default",
		.addresses = "reg",
		.match = NULL,
		.count_cells = of_bus_default_count_cells,
		.map = of_bus_default_map,
		.translate = of_bus_default_translate,
		.get_flags = of_bus_default_get_flags,
	},
};

static struct of_bus *of_match_bus(struct device_node *np)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(of_busses); i++)
		if (!of_busses[i].match || of_busses[i].match(np))
			return &of_busses[i];
	BUG();
	return NULL;
}

static int of_empty_ranges_quirk(struct device_node *np)
{
	if (IS_ENABLED(CONFIG_PPC)) {
		/* To save cycles, we cache the result for global "Mac" setting */
		static int quirk_state = -1;

		/* PA-SEMI sdc DT bug */
		if (of_device_is_compatible(np, "1682m-sdc"))
			return true;

		/* Make quirk cached */
		if (quirk_state < 0)
			quirk_state =
				of_machine_is_compatible("Power Macintosh") ||
				of_machine_is_compatible("MacRISC");
		return quirk_state;
	}
	return false;
}

static int 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)
{
	const __be32 *ranges;
	unsigned int rlen;
	int rone;
	u64 offset = OF_BAD_ADDR;

	/*
	 * Normally, an absence of a "ranges" property means we are
	 * crossing a non-translatable boundary, and thus the addresses
	 * below the current cannot be converted to CPU physical ones.
	 * Unfortunately, while this is very clear in the spec, it's not
	 * what Apple understood, and they do have things like /uni-n or
	 * /ht nodes with no "ranges" property and a lot of perfectly
	 * useable mapped devices below them. Thus we treat the absence of
	 * "ranges" as equivalent to an empty "ranges" property which means
	 * a 1:1 translation at that level. It's up to the caller not to try
	 * to translate addresses that aren't supposed to be translated in
	 * the first place. --BenH.
	 *
	 * As far as we know, this damage only exists on Apple machines, so
	 * This code is only enabled on powerpc. --gcl
	 *
	 * This quirk also applies for 'dma-ranges' which frequently exist in
	 * child nodes without 'dma-ranges' in the parent nodes. --RobH
	 */
	ranges = of_get_property(parent, rprop, &rlen);
	if (ranges == NULL && !of_empty_ranges_quirk(parent) &&
	    strcmp(rprop, "dma-ranges")) {
		pr_debug("no ranges; cannot translate\n");
		return 1;
	}
	if (ranges == NULL || rlen == 0) {
		offset = of_read_number(addr, na);
		memset(addr, 0, pna * 4);
		pr_debug("empty ranges; 1:1 translation\n");
		goto finish;
	}

	pr_debug("walking ranges...\n");

	/* Now walk through the ranges */
	rlen /= 4;
	rone = na + pna + ns;
	for (; rlen >= rone; rlen -= rone, ranges += rone) {
		offset = bus->map(addr, ranges, na, ns, pna);
		if (offset != OF_BAD_ADDR)
			break;
	}
	if (offset == OF_BAD_ADDR) {
		pr_debug("not found !\n");
		return 1;
	}
	memcpy(addr, ranges + na, 4 * pna);

 finish:
	of_dump_addr("parent translation for:", addr, pna);
	pr_debug("with offset: %llx\n", offset);

	/* Translate it into parent bus space */
	return pbus->translate(addr, offset, pna);
}

/*
 * Translate an address from the device-tree into a CPU physical address,
 * this walks up the tree and applies the various bus mappings on the
 * way.
 *
 * Note: We consider that crossing any level with #size-cells == 0 to mean
 * that translation is impossible (that is we are not dealing with a value
 * that can be mapped to a cpu physical address). This is not really specified
 * that way, but this is traditionally the way IBM at least do things
 *
 * Whenever the translation fails, the *host pointer will be set to the
 * device that had registered logical PIO mapping, and the return code is
 * relative to that node.
 */
static u64 __of_translate_address(struct device_node *dev,
				  struct device_node *(*get_parent)(const struct device_node *),
				  const __be32 *in_addr, const char *rprop,
				  struct device_node **host)
{
	struct device_node *parent = NULL;
	struct of_bus *bus, *pbus;
	__be32 addr[OF_MAX_ADDR_CELLS];
	int na, ns, pna, pns;
	u64 result = OF_BAD_ADDR;

	pr_debug("** translation for device %pOF **\n", dev);

	/* Increase refcount at current level */
	of_node_get(dev);

	*host = NULL;
	/* Get parent & match bus type */
	parent = get_parent(dev);
	if (parent == NULL)
		goto bail;
	bus = of_match_bus(parent);

	/* Count address cells & copy address locally */
	bus->count_cells(dev, &na, &ns);
	if (!OF_CHECK_COUNTS(na, ns)) {
		pr_debug("Bad cell count for %pOF\n", dev);
		goto bail;
	}
	memcpy(addr, in_addr, na * 4);

	pr_debug("bus is %s (na=%d, ns=%d) on %pOF\n",
	    bus->name, na, ns, parent);
	of_dump_addr("translating address:", addr, na);

	/* Translate */
	for (;;) {
		struct logic_pio_hwaddr *iorange;

		/* Switch to parent bus */
		of_node_put(dev);
		dev = parent;
		parent = get_parent(dev);

		/* If root, we have finished */
		if (parent == NULL) {
			pr_debug("reached root node\n");
			result = of_read_number(addr, na);
			break;
		}

		/*
		 * For indirectIO device which has no ranges property, get
		 * the address from reg directly.
		 */
		iorange = find_io_range_by_fwnode(&dev->fwnode);
		if (iorange && (iorange->flags != LOGIC_PIO_CPU_MMIO)) {
			result = of_read_number(addr + 1, na - 1);
			pr_debug("indirectIO matched(%pOF) 0x%llx\n",
				 dev, result);
			*host = of_node_get(dev);
			break;
		}

		/* Get new parent bus and counts */
		pbus = of_match_bus(parent);
		pbus->count_cells(dev, &pna, &pns);
		if (!OF_CHECK_COUNTS(pna, pns)) {
			pr_err("Bad cell count for %pOF\n", dev);
			break;
		}

		pr_debug("parent bus is %s (na=%d, ns=%d) on %pOF\n",
		    pbus->name, pna, pns, parent);

		/* Apply bus translation */
		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
			break;

		/* Complete the move up one level */
		na = pna;
		ns = pns;
		bus = pbus;

		of_dump_addr("one level translation:", addr, na);
	}
 bail:
	of_node_put(parent);
	of_node_put(dev);

	return result;
}

u64 of_translate_address(struct device_node *dev, const __be32 *in_addr)
{
	struct device_node *host;
	u64 ret;

	ret = __of_translate_address(dev, of_get_parent,
				     in_addr, "ranges", &host);
	if (host) {
		of_node_put(host);
		return OF_BAD_ADDR;
	}

	return ret;
}
EXPORT_SYMBOL(of_translate_address);

#ifdef CONFIG_HAS_DMA
struct device_node *__of_get_dma_parent(const struct device_node *np)
{
	struct of_phandle_args args;
	int ret, index;

	index = of_property_match_string(np, "interconnect-names", "dma-mem");
	if (index < 0)
		return of_get_parent(np);

	ret = of_parse_phandle_with_args(np, "interconnects",
					 "#interconnect-cells",
					 index, &args);
	if (ret < 0)
		return of_get_parent(np);

	return of_node_get(args.np);
}
#endif

static struct device_node *of_get_next_dma_parent(struct device_node *np)
{
	struct device_node *parent;

	parent = __of_get_dma_parent(np);
	of_node_put(np);

	return parent;
}

u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr)
{
	struct device_node *host;
	u64 ret;

	ret = __of_translate_address(dev, __of_get_dma_parent,
				     in_addr, "dma-ranges", &host);

	if (host) {
		of_node_put(host);
		return OF_BAD_ADDR;
	}

	return ret;
}
EXPORT_SYMBOL(of_translate_dma_address);

/**
 * of_translate_dma_region - Translate device tree address and size tuple
 * @dev: device tree node for which to translate
 * @prop: pointer into array of cells
 * @start: return value for the start of the DMA range
 * @length: return value for the length of the DMA range
 *
 * Returns a pointer to the cell immediately following the translated DMA region.
 */
const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *prop,
				      phys_addr_t *start, size_t *length)
{
	struct device_node *parent;
	u64 address, size;
	int na, ns;

	parent = __of_get_dma_parent(dev);
	if (!parent)
		return NULL;

	na = of_bus_n_addr_cells(parent);
	ns = of_bus_n_size_cells(parent);

	of_node_put(parent);

	address = of_translate_dma_address(dev, prop);
	if (address == OF_BAD_ADDR)
		return NULL;

	size = of_read_number(prop + na, ns);

	if (start)
		*start = address;

	if (length)
		*length = size;

	return prop + na + ns;
}
EXPORT_SYMBOL(of_translate_dma_region);

const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no,
			       u64 *size, unsigned int *flags)
{
	const __be32 *prop;
	unsigned int psize;
	struct device_node *parent;
	struct of_bus *bus;
	int onesize, i, na, ns;

	/* Get parent & match bus type */
	parent = of_get_parent(dev);
	if (parent == NULL)
		return NULL;
	bus = of_match_bus(parent);
	if (strcmp(bus->name, "pci") && (bar_no >= 0)) {
		of_node_put(parent);
		return NULL;
	}
	bus->count_cells(dev, &na, &ns);
	of_node_put(parent);
	if (!OF_CHECK_ADDR_COUNT(na))
		return NULL;

	/* Get "reg" or "assigned-addresses" property */
	prop = of_get_property(dev, bus->addresses, &psize);
	if (prop == NULL)
		return NULL;
	psize /= 4;

	onesize = na + ns;
	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {
		u32 val = be32_to_cpu(prop[0]);
		/* PCI bus matches on BAR number instead of index */
		if (((bar_no >= 0) && ((val & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0))) ||
		    ((index >= 0) && (i == index))) {
			if (size)
				*size = of_read_number(prop + na, ns);
			if (flags)
				*flags = bus->get_flags(prop);
			return prop;
		}
	}
	return NULL;
}
EXPORT_SYMBOL(__of_get_address);

/**
 * of_property_read_reg - Retrieve the specified "reg" entry index without translating
 * @np: device tree node for which to retrieve "reg" from
 * @idx: "reg" entry index to read
 * @addr: return value for the untranslated address
 * @size: return value for the entry size
 *
 * Returns -EINVAL if "reg" is not found. Returns 0 on success with addr and
 * size values filled in.
 */
int of_property_read_reg(struct device_node *np, int idx, u64 *addr, u64 *size)
{
	const __be32 *prop = of_get_address(np, idx, size, NULL);

	if (!prop)
		return -EINVAL;

	*addr = of_read_number(prop, of_n_addr_cells(np));

	return 0;
}
EXPORT_SYMBOL(of_property_read_reg);

static int parser_init(struct of_pci_range_parser *parser,
			struct device_node *node, const char *name)
{
	int rlen;

	parser->node = node;
	parser->pna = of_n_addr_cells(node);
	parser->na = of_bus_n_addr_cells(node);
	parser->ns = of_bus_n_size_cells(node);
	parser->dma = !strcmp(name, "dma-ranges");
	parser->bus = of_match_bus(node);

	parser->range = of_get_property(node, name, &rlen);
	if (parser->range == NULL)
		return -ENOENT;

	parser->end = parser->range + rlen / sizeof(__be32);

	return 0;
}

int of_pci_range_parser_init(struct of_pci_range_parser *parser,
				struct device_node *node)
{
	return parser_init(parser, node, "ranges");
}
EXPORT_SYMBOL_GPL(of_pci_range_parser_init);

int of_pci_dma_range_parser_init(struct of_pci_range_parser *parser,
				struct device_node *node)
{
	return parser_init(parser, node, "dma-ranges");
}
EXPORT_SYMBOL_GPL(of_pci_dma_range_parser_init);
#define of_dma_range_parser_init of_pci_dma_range_parser_init

struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
						struct of_pci_range *range)
{
	int na = parser->na;
	int ns = parser->ns;
	int np = parser->pna + na + ns;
	int busflag_na = 0;

	if (!range)
		return NULL;

	if (!parser->range || parser->range + np > parser->end)
		return NULL;

	range->flags = parser->bus->get_flags(parser->range);

	/* A extra cell for resource flags */
	if (parser->bus->has_flags)
		busflag_na = 1;

	range->bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);

	if (parser->dma)
		range->cpu_addr = of_translate_dma_address(parser->node,
				parser->range + na);
	else
		range->cpu_addr = of_translate_address(parser->node,
				parser->range + na);
	range->size = of_read_number(parser->range + parser->pna + na, ns);

	parser->range += np;

	/* Now consume following elements while they are contiguous */
	while (parser->range + np <= parser->end) {
		u32 flags = 0;
		u64 bus_addr, cpu_addr, size;

		flags = parser->bus->get_flags(parser->range);
		bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);
		if (parser->dma)
			cpu_addr = of_translate_dma_address(parser->node,
					parser->range + na);
		else
			cpu_addr = of_translate_address(parser->node,
					parser->range + na);
		size = of_read_number(parser->range + parser->pna + na, ns);

		if (flags != range->flags)
			break;
		if (bus_addr != range->bus_addr + range->size ||
		    cpu_addr != range->cpu_addr + range->size)
			break;

		range->size += size;
		parser->range += np;
	}

	return range;
}
EXPORT_SYMBOL_GPL(of_pci_range_parser_one);

static u64 of_translate_ioport(struct device_node *dev, const __be32 *in_addr,
			u64 size)
{
	u64 taddr;
	unsigned long port;
	struct device_node *host;

	taddr = __of_translate_address(dev, of_get_parent,
				       in_addr, "ranges", &host);
	if (host) {
		/* host-specific port access */
		port = logic_pio_trans_hwaddr(&host->fwnode, taddr, size);
		of_node_put(host);
	} else {
		/* memory-mapped I/O range */
		port = pci_address_to_pio(taddr);
	}

	if (port == (unsigned long)-1)
		return OF_BAD_ADDR;

	return port;
}

#ifdef CONFIG_HAS_DMA
/**
 * of_dma_get_range - Get DMA range info and put it into a map array
 * @np:		device node to get DMA range info
 * @map:	dma range structure to return
 *
 * Look in bottom up direction for the first "dma-ranges" property
 * and parse it.  Put the information into a DMA offset map array.
 *
 * dma-ranges format:
 *	DMA addr (dma_addr)	: naddr cells
 *	CPU addr (phys_addr_t)	: pna cells
 *	size			: nsize cells
 *
 * It returns -ENODEV if "dma-ranges" property was not found for this
 * device in the DT.
 */
int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
{
	struct device_node *node = of_node_get(np);
	const __be32 *ranges = NULL;
	bool found_dma_ranges = false;
	struct of_range_parser parser;
	struct of_range range;
	struct bus_dma_region *r;
	int len, num_ranges = 0;
	int ret = 0;

	while (node) {
		ranges = of_get_property(node, "dma-ranges", &len);

		/* Ignore empty ranges, they imply no translation required */
		if (ranges && len > 0)
			break;

		/* Once we find 'dma-ranges', then a missing one is an error */
		if (found_dma_ranges && !ranges) {
			ret = -ENODEV;
			goto out;
		}
		found_dma_ranges = true;

		node = of_get_next_dma_parent(node);
	}

	if (!node || !ranges) {
		pr_debug("no dma-ranges found for node(%pOF)\n", np);
		ret = -ENODEV;
		goto out;
	}

	of_dma_range_parser_init(&parser, node);
	for_each_of_range(&parser, &range) {
		if (range.cpu_addr == OF_BAD_ADDR) {
			pr_err("translation of DMA address(%llx) to CPU address failed node(%pOF)\n",
			       range.bus_addr, node);
			continue;
		}
		num_ranges++;
	}

	if (!num_ranges) {
		ret = -EINVAL;
		goto out;
	}

	r = kcalloc(num_ranges + 1, sizeof(*r), GFP_KERNEL);
	if (!r) {
		ret = -ENOMEM;
		goto out;
	}

	/*
	 * Record all info in the generic DMA ranges array for struct device,
	 * returning an error if we don't find any parsable ranges.
	 */
	*map = r;
	of_dma_range_parser_init(&parser, node);
	for_each_of_range(&parser, &range) {
		pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
			 range.bus_addr, range.cpu_addr, range.size);
		if (range.cpu_addr == OF_BAD_ADDR)
			continue;
		r->cpu_start = range.cpu_addr;
		r->dma_start = range.bus_addr;
		r->size = range.size;
		r->offset = range.cpu_addr - range.bus_addr;
		r++;
	}
out:
	of_node_put(node);
	return ret;
}
#endif /* CONFIG_HAS_DMA */

/**
 * of_dma_get_max_cpu_address - Gets highest CPU address suitable for DMA
 * @np: The node to start searching from or NULL to start from the root
 *
 * Gets the highest CPU physical address that is addressable by all DMA masters
 * in the sub-tree pointed by np, or the whole tree if NULL is passed. If no
 * DMA constrained device is found, it returns PHYS_ADDR_MAX.
 */
phys_addr_t __init of_dma_get_max_cpu_address(struct device_node *np)
{
	phys_addr_t max_cpu_addr = PHYS_ADDR_MAX;
	struct of_range_parser parser;
	phys_addr_t subtree_max_addr;
	struct device_node *child;
	struct of_range range;
	const __be32 *ranges;
	u64 cpu_end = 0;
	int len;

	if (!np)
		np = of_root;

	ranges = of_get_property(np, "dma-ranges", &len);
	if (ranges && len) {
		of_dma_range_parser_init(&parser, np);
		for_each_of_range(&parser, &range)
			if (range.cpu_addr + range.size > cpu_end)
				cpu_end = range.cpu_addr + range.size - 1;

		if (max_cpu_addr > cpu_end)
			max_cpu_addr = cpu_end;
	}

	for_each_available_child_of_node(np, child) {
		subtree_max_addr = of_dma_get_max_cpu_address(child);
		if (max_cpu_addr > subtree_max_addr)
			max_cpu_addr = subtree_max_addr;
	}

	return max_cpu_addr;
}

/**
 * of_dma_is_coherent - Check if device is coherent
 * @np:	device node
 *
 * It returns true if "dma-coherent" property was found
 * for this device in the DT, or if DMA is coherent by
 * default for OF devices on the current platform and no
 * "dma-noncoherent" property was found for this device.
 */
bool of_dma_is_coherent(struct device_node *np)
{
	struct device_node *node;
	bool is_coherent = dma_default_coherent;

	node = of_node_get(np);

	while (node) {
		if (of_property_read_bool(node, "dma-coherent")) {
			is_coherent = true;
			break;
		}
		if (of_property_read_bool(node, "dma-noncoherent")) {
			is_coherent = false;
			break;
		}
		node = of_get_next_dma_parent(node);
	}
	of_node_put(node);
	return is_coherent;
}
EXPORT_SYMBOL_GPL(of_dma_is_coherent);

/**
 * of_mmio_is_nonposted - Check if device uses non-posted MMIO
 * @np:	device node
 *
 * Returns true if the "nonposted-mmio" property was found for
 * the device's bus.
 *
 * This is currently only enabled on builds that support Apple ARM devices, as
 * an optimization.
 */
static bool of_mmio_is_nonposted(struct device_node *np)
{
	struct device_node *parent;
	bool nonposted;

	if (!IS_ENABLED(CONFIG_ARCH_APPLE))
		return false;

	parent = of_get_parent(np);
	if (!parent)
		return false;

	nonposted = of_property_read_bool(parent, "nonposted-mmio");

	of_node_put(parent);
	return nonposted;
}

static int __of_address_to_resource(struct device_node *dev, int index, int bar_no,
		struct resource *r)
{
	u64 taddr;
	const __be32	*addrp;
	u64		size;
	unsigned int	flags;
	const char	*name = NULL;

	addrp = __of_get_address(dev, index, bar_no, &size, &flags);
	if (addrp == NULL)
		return -EINVAL;

	/* Get optional "reg-names" property to add a name to a resource */
	if (index >= 0)
		of_property_read_string_index(dev, "reg-names",	index, &name);

	if (flags & IORESOURCE_MEM)
		taddr = of_translate_address(dev, addrp);
	else if (flags & IORESOURCE_IO)
		taddr = of_translate_ioport(dev, addrp, size);
	else
		return -EINVAL;

	if (taddr == OF_BAD_ADDR)
		return -EINVAL;
	memset(r, 0, sizeof(struct resource));

	if (of_mmio_is_nonposted(dev))
		flags |= IORESOURCE_MEM_NONPOSTED;

	r->start = taddr;
	r->end = taddr + size - 1;
	r->flags = flags;
	r->name = name ? name : dev->full_name;

	return 0;
}

/**
 * of_address_to_resource - Translate device tree address and return as resource
 * @dev:	Caller's Device Node
 * @index:	Index into the array
 * @r:		Pointer to resource array
 *
 * Returns -EINVAL if the range cannot be converted to resource.
 *
 * Note that if your address is a PIO address, the conversion will fail if
 * the physical address can't be internally converted to an IO token with
 * pci_address_to_pio(), that is because it's either called too early or it
 * can't be matched to any host bridge IO space
 */
int of_address_to_resource(struct device_node *dev, int index,
			   struct resource *r)
{
	return __of_address_to_resource(dev, index, -1, r);
}
EXPORT_SYMBOL_GPL(of_address_to_resource);

int of_pci_address_to_resource(struct device_node *dev, int bar,
			       struct resource *r)
{

	if (!IS_ENABLED(CONFIG_PCI))
		return -ENOSYS;

	return __of_address_to_resource(dev, -1, bar, r);
}
EXPORT_SYMBOL_GPL(of_pci_address_to_resource);

/**
 * of_iomap - Maps the memory mapped IO for a given device_node
 * @np:		the device whose io range will be mapped
 * @index:	index of the io range
 *
 * Returns a pointer to the mapped memory
 */
void __iomem *of_iomap(struct device_node *np, int index)
{
	struct resource res;

	if (of_address_to_resource(np, index, &res))
		return NULL;

	if (res.flags & IORESOURCE_MEM_NONPOSTED)
		return ioremap_np(res.start, resource_size(&res));
	else
		return ioremap(res.start, resource_size(&res));
}
EXPORT_SYMBOL(of_iomap);

/*
 * of_io_request_and_map - Requests a resource and maps the memory mapped IO
 *			   for a given device_node
 * @device:	the device whose io range will be mapped
 * @index:	index of the io range
 * @name:	name "override" for the memory region request or NULL
 *
 * Returns a pointer to the requested and mapped memory or an ERR_PTR() encoded
 * error code on failure. Usage example:
 *
 *	base = of_io_request_and_map(node, 0, "foo");
 *	if (IS_ERR(base))
 *		return PTR_ERR(base);
 */
void __iomem *of_io_request_and_map(struct device_node *np, int index,
				    const char *name)
{
	struct resource res;
	void __iomem *mem;

	if (of_address_to_resource(np, index, &res))
		return IOMEM_ERR_PTR(-EINVAL);

	if (!name)
		name = res.name;
	if (!request_mem_region(res.start, resource_size(&res), name))
		return IOMEM_ERR_PTR(-EBUSY);

	if (res.flags & IORESOURCE_MEM_NONPOSTED)
		mem = ioremap_np(res.start, resource_size(&res));
	else
		mem = ioremap(res.start, resource_size(&res));

	if (!mem) {
		release_mem_region(res.start, resource_size(&res));
		return IOMEM_ERR_PTR(-ENOMEM);
	}

	return mem;
}
EXPORT_SYMBOL(of_io_request_and_map);