summaryrefslogtreecommitdiffstats
path: root/drivers/pci/setup-bus.c
blob: 19b111383f62fe63c9859dfd509de2cda3801d9e (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
/*
 *	drivers/pci/setup-bus.c
 *
 * Extruded from code written by
 *      Dave Rusling (david.rusling@reo.mts.dec.com)
 *      David Mosberger (davidm@cs.arizona.edu)
 *	David Miller (davem@redhat.com)
 *
 * Support routines for initializing a PCI subsystem.
 */

/*
 * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
 *	     PCI-PCI bridges cleanup, sorted resource allocation.
 * Feb 2002, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
 *	     Converted to allocation in 3 passes, which gives
 *	     tighter packing. Prefetchable range support.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/cache.h>
#include <linux/slab.h>
#include "pci.h"

struct resource_list_x {
	struct resource_list_x *next;
	struct resource *res;
	struct pci_dev *dev;
	resource_size_t start;
	resource_size_t end;
	unsigned long flags;
};

static void add_to_failed_list(struct resource_list_x *head,
				 struct pci_dev *dev, struct resource *res)
{
	struct resource_list_x *list = head;
	struct resource_list_x *ln = list->next;
	struct resource_list_x *tmp;

	tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
	if (!tmp) {
		pr_warning("add_to_failed_list: kmalloc() failed!\n");
		return;
	}

	tmp->next = ln;
	tmp->res = res;
	tmp->dev = dev;
	tmp->start = res->start;
	tmp->end = res->end;
	tmp->flags = res->flags;
	list->next = tmp;
}

static void free_failed_list(struct resource_list_x *head)
{
	struct resource_list_x *list, *tmp;

	for (list = head->next; list;) {
		tmp = list;
		list = list->next;
		kfree(tmp);
	}

	head->next = NULL;
}

static void __dev_sort_resources(struct pci_dev *dev,
				 struct resource_list *head)
{
	u16 class = dev->class >> 8;

	/* Don't touch classless devices or host bridges or ioapics.  */
	if (class == PCI_CLASS_NOT_DEFINED || class == PCI_CLASS_BRIDGE_HOST)
		return;

	/* Don't touch ioapic devices already enabled by firmware */
	if (class == PCI_CLASS_SYSTEM_PIC) {
		u16 command;
		pci_read_config_word(dev, PCI_COMMAND, &command);
		if (command & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY))
			return;
	}

	pdev_sort_resources(dev, head);
}

static void __assign_resources_sorted(struct resource_list *head,
				 struct resource_list_x *fail_head)
{
	struct resource *res;
	struct resource_list *list, *tmp;
	int idx;

	for (list = head->next; list;) {
		res = list->res;
		idx = res - &list->dev->resource[0];

		if (pci_assign_resource(list->dev, idx)) {
			if (fail_head && !pci_is_root_bus(list->dev->bus)) {
				/*
				 * if the failed res is for ROM BAR, and it will
				 * be enabled later, don't add it to the list
				 */
				if (!((idx == PCI_ROM_RESOURCE) &&
				      (!(res->flags & IORESOURCE_ROM_ENABLE))))
					add_to_failed_list(fail_head, list->dev, res);
			}
			res->start = 0;
			res->end = 0;
			res->flags = 0;
		}
		tmp = list;
		list = list->next;
		kfree(tmp);
	}
}

static void pdev_assign_resources_sorted(struct pci_dev *dev,
				 struct resource_list_x *fail_head)
{
	struct resource_list head;

	head.next = NULL;
	__dev_sort_resources(dev, &head);
	__assign_resources_sorted(&head, fail_head);

}

static void pbus_assign_resources_sorted(const struct pci_bus *bus,
					 struct resource_list_x *fail_head)
{
	struct pci_dev *dev;
	struct resource_list head;

	head.next = NULL;
	list_for_each_entry(dev, &bus->devices, bus_list)
		__dev_sort_resources(dev, &head);

	__assign_resources_sorted(&head, fail_head);
}

void pci_setup_cardbus(struct pci_bus *bus)
{
	struct pci_dev *bridge = bus->self;
	struct resource *res;
	struct pci_bus_region region;

	dev_info(&bridge->dev, "CardBus bridge to [bus %02x-%02x]\n",
		 bus->secondary, bus->subordinate);

	res = bus->resource[0];
	pcibios_resource_to_bus(bridge, &region, res);
	if (res->flags & IORESOURCE_IO) {
		/*
		 * The IO resource is allocated a range twice as large as it
		 * would normally need.  This allows us to set both IO regs.
		 */
		dev_info(&bridge->dev, "  bridge window %pR\n", res);
		pci_write_config_dword(bridge, PCI_CB_IO_BASE_0,
					region.start);
		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0,
					region.end);
	}

	res = bus->resource[1];
	pcibios_resource_to_bus(bridge, &region, res);
	if (res->flags & IORESOURCE_IO) {
		dev_info(&bridge->dev, "  bridge window %pR\n", res);
		pci_write_config_dword(bridge, PCI_CB_IO_BASE_1,
					region.start);
		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1,
					region.end);
	}

	res = bus->resource[2];
	pcibios_resource_to_bus(bridge, &region, res);
	if (res->flags & IORESOURCE_MEM) {
		dev_info(&bridge->dev, "  bridge window %pR\n", res);
		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0,
					region.start);
		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0,
					region.end);
	}

	res = bus->resource[3];
	pcibios_resource_to_bus(bridge, &region, res);
	if (res->flags & IORESOURCE_MEM) {
		dev_info(&bridge->dev, "  bridge window %pR\n", res);
		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_1,
					region.start);
		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_1,
					region.end);
	}
}
EXPORT_SYMBOL(pci_setup_cardbus);

/* Initialize bridges with base/limit values we have collected.
   PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
   requires that if there is no I/O ports or memory behind the
   bridge, corresponding range must be turned off by writing base
   value greater than limit to the bridge's base/limit registers.

   Note: care must be taken when updating I/O base/limit registers
   of bridges which support 32-bit I/O. This update requires two
   config space writes, so it's quite possible that an I/O window of
   the bridge will have some undesirable address (e.g. 0) after the
   first write. Ditto 64-bit prefetchable MMIO.  */
static void pci_setup_bridge_io(struct pci_bus *bus)
{
	struct pci_dev *bridge = bus->self;
	struct resource *res;
	struct pci_bus_region region;
	u32 l, io_upper16;

	/* Set up the top and bottom of the PCI I/O segment for this bus. */
	res = bus->resource[0];
	pcibios_resource_to_bus(bridge, &region, res);
	if (res->flags & IORESOURCE_IO) {
		pci_read_config_dword(bridge, PCI_IO_BASE, &l);
		l &= 0xffff0000;
		l |= (region.start >> 8) & 0x00f0;
		l |= region.end & 0xf000;
		/* Set up upper 16 bits of I/O base/limit. */
		io_upper16 = (region.end & 0xffff0000) | (region.start >> 16);
		dev_info(&bridge->dev, "  bridge window %pR\n", res);
	} else {
		/* Clear upper 16 bits of I/O base/limit. */
		io_upper16 = 0;
		l = 0x00f0;
		dev_info(&bridge->dev, "  bridge window [io  disabled]\n");
	}
	/* Temporarily disable the I/O range before updating PCI_IO_BASE. */
	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, 0x0000ffff);
	/* Update lower 16 bits of I/O base/limit. */
	pci_write_config_dword(bridge, PCI_IO_BASE, l);
	/* Update upper 16 bits of I/O base/limit. */
	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, io_upper16);
}

static void pci_setup_bridge_mmio(struct pci_bus *bus)
{
	struct pci_dev *bridge = bus->self;
	struct resource *res;
	struct pci_bus_region region;
	u32 l;

	/* Set up the top and bottom of the PCI Memory segment for this bus. */
	res = bus->resource[1];
	pcibios_resource_to_bus(bridge, &region, res);
	if (res->flags & IORESOURCE_MEM) {
		l = (region.start >> 16) & 0xfff0;
		l |= region.end & 0xfff00000;
		dev_info(&bridge->dev, "  bridge window %pR\n", res);
	} else {
		l = 0x0000fff0;
		dev_info(&bridge->dev, "  bridge window [mem disabled]\n");
	}
	pci_write_config_dword(bridge, PCI_MEMORY_BASE, l);
}

static void pci_setup_bridge_mmio_pref(struct pci_bus *bus)
{
	struct pci_dev *bridge = bus->self;
	struct resource *res;
	struct pci_bus_region region;
	u32 l, bu, lu;

	/* Clear out the upper 32 bits of PREF limit.
	   If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily
	   disables PREF range, which is ok. */
	pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0);

	/* Set up PREF base/limit. */
	bu = lu = 0;
	res = bus->resource[2];
	pcibios_resource_to_bus(bridge, &region, res);
	if (res->flags & IORESOURCE_PREFETCH) {
		l = (region.start >> 16) & 0xfff0;
		l |= region.end & 0xfff00000;
		if (res->flags & IORESOURCE_MEM_64) {
			bu = upper_32_bits(region.start);
			lu = upper_32_bits(region.end);
		}
		dev_info(&bridge->dev, "  bridge window %pR\n", res);
	} else {
		l = 0x0000fff0;
		dev_info(&bridge->dev, "  bridge window [mem pref disabled]\n");
	}
	pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);

	/* Set the upper 32 bits of PREF base & limit. */
	pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu);
	pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu);
}

static void __pci_setup_bridge(struct pci_bus *bus, unsigned long type)
{
	struct pci_dev *bridge = bus->self;

	dev_info(&bridge->dev, "PCI bridge to [bus %02x-%02x]\n",
		 bus->secondary, bus->subordinate);

	if (type & IORESOURCE_IO)
		pci_setup_bridge_io(bus);

	if (type & IORESOURCE_MEM)
		pci_setup_bridge_mmio(bus);

	if (type & IORESOURCE_PREFETCH)
		pci_setup_bridge_mmio_pref(bus);

	pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl);
}

static void pci_setup_bridge(struct pci_bus *bus)
{
	unsigned long type = IORESOURCE_IO | IORESOURCE_MEM |
				  IORESOURCE_PREFETCH;

	__pci_setup_bridge(bus, type);
}

/* Check whether the bridge supports optional I/O and
   prefetchable memory ranges. If not, the respective
   base/limit registers must be read-only and read as 0. */
static void pci_bridge_check_ranges(struct pci_bus *bus)
{
	u16 io;
	u32 pmem;
	struct pci_dev *bridge = bus->self;
	struct resource *b_res;

	b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
	b_res[1].flags |= IORESOURCE_MEM;

	pci_read_config_word(bridge, PCI_IO_BASE, &io);
	if (!io) {
		pci_write_config_word(bridge, PCI_IO_BASE, 0xf0f0);
		pci_read_config_word(bridge, PCI_IO_BASE, &io);
 		pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
 	}
 	if (io)
		b_res[0].flags |= IORESOURCE_IO;
	/*  DECchip 21050 pass 2 errata: the bridge may miss an address
	    disconnect boundary by one PCI data phase.
	    Workaround: do not use prefetching on this device. */
	if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
		return;
	pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
	if (!pmem) {
		pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
					       0xfff0fff0);
		pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
		pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
	}
	if (pmem) {
		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
		if ((pmem & PCI_PREF_RANGE_TYPE_MASK) ==
		    PCI_PREF_RANGE_TYPE_64) {
			b_res[2].flags |= IORESOURCE_MEM_64;
			b_res[2].flags |= PCI_PREF_RANGE_TYPE_64;
		}
	}

	/* double check if bridge does support 64 bit pref */
	if (b_res[2].flags & IORESOURCE_MEM_64) {
		u32 mem_base_hi, tmp;
		pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32,
					 &mem_base_hi);
		pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
					       0xffffffff);
		pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp);
		if (!tmp)
			b_res[2].flags &= ~IORESOURCE_MEM_64;
		pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
				       mem_base_hi);
	}
}

/* Helper function for sizing routines: find first available
   bus resource of a given type. Note: we intentionally skip
   the bus resources which have already been assigned (that is,
   have non-NULL parent resource). */
static struct resource *find_free_bus_resource(struct pci_bus *bus, unsigned long type)
{
	int i;
	struct resource *r;
	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
				  IORESOURCE_PREFETCH;

	pci_bus_for_each_resource(bus, r, i) {
		if (r == &ioport_resource || r == &iomem_resource)
			continue;
		if (r && (r->flags & type_mask) == type && !r->parent)
			return r;
	}
	return NULL;
}

/* Sizing the IO windows of the PCI-PCI bridge is trivial,
   since these windows have 4K granularity and the IO ranges
   of non-bridge PCI devices are limited to 256 bytes.
   We must be careful with the ISA aliasing though. */
static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size)
{
	struct pci_dev *dev;
	struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
	unsigned long size = 0, size1 = 0, old_size;

	if (!b_res)
 		return;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		int i;

		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
			struct resource *r = &dev->resource[i];
			unsigned long r_size;

			if (r->parent || !(r->flags & IORESOURCE_IO))
				continue;
			r_size = resource_size(r);

			if (r_size < 0x400)
				/* Might be re-aligned for ISA */
				size += r_size;
			else
				size1 += r_size;
		}
	}
	if (size < min_size)
		size = min_size;
	old_size = resource_size(b_res);
	if (old_size == 1)
		old_size = 0;
/* To be fixed in 2.5: we should have sort of HAVE_ISA
   flag in the struct pci_bus. */
#if defined(CONFIG_ISA) || defined(CONFIG_EISA)
	size = (size & 0xff) + ((size & ~0xffUL) << 2);
#endif
	size = ALIGN(size + size1, 4096);
	if (size < old_size)
		size = old_size;
	if (!size) {
		if (b_res->start || b_res->end)
			dev_info(&bus->self->dev, "disabling bridge window "
				 "%pR to [bus %02x-%02x] (unused)\n", b_res,
				 bus->secondary, bus->subordinate);
		b_res->flags = 0;
		return;
	}
	/* Alignment of the IO window is always 4K */
	b_res->start = 4096;
	b_res->end = b_res->start + size - 1;
	b_res->flags |= IORESOURCE_STARTALIGN;
}

/* Calculate the size of the bus and minimal alignment which
   guarantees that all child resources fit in this size. */
static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
			 unsigned long type, resource_size_t min_size)
{
	struct pci_dev *dev;
	resource_size_t min_align, align, size, old_size;
	resource_size_t aligns[12];	/* Alignments from 1Mb to 2Gb */
	int order, max_order;
	struct resource *b_res = find_free_bus_resource(bus, type);
	unsigned int mem64_mask = 0;

	if (!b_res)
		return 0;

	memset(aligns, 0, sizeof(aligns));
	max_order = 0;
	size = 0;

	mem64_mask = b_res->flags & IORESOURCE_MEM_64;
	b_res->flags &= ~IORESOURCE_MEM_64;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		int i;

		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
			struct resource *r = &dev->resource[i];
			resource_size_t r_size;

			if (r->parent || (r->flags & mask) != type)
				continue;
			r_size = resource_size(r);
			/* For bridges size != alignment */
			align = pci_resource_alignment(dev, r);
			order = __ffs(align) - 20;
			if (order > 11) {
				dev_warn(&dev->dev, "disabling BAR %d: %pR "
					 "(bad alignment %#llx)\n", i, r,
					 (unsigned long long) align);
				r->flags = 0;
				continue;
			}
			size += r_size;
			if (order < 0)
				order = 0;
			/* Exclude ranges with size > align from
			   calculation of the alignment. */
			if (r_size == align)
				aligns[order] += align;
			if (order > max_order)
				max_order = order;
			mem64_mask &= r->flags & IORESOURCE_MEM_64;
		}
	}
	if (size < min_size)
		size = min_size;
	old_size = resource_size(b_res);
	if (old_size == 1)
		old_size = 0;
	if (size < old_size)
		size = old_size;

	align = 0;
	min_align = 0;
	for (order = 0; order <= max_order; order++) {
		resource_size_t align1 = 1;

		align1 <<= (order + 20);

		if (!align)
			min_align = align1;
		else if (ALIGN(align + min_align, min_align) < align1)
			min_align = align1 >> 1;
		align += aligns[order];
	}
	size = ALIGN(size, min_align);
	if (!size) {
		if (b_res->start || b_res->end)
			dev_info(&bus->self->dev, "disabling bridge window "
				 "%pR to [bus %02x-%02x] (unused)\n", b_res,
				 bus->secondary, bus->subordinate);
		b_res->flags = 0;
		return 1;
	}
	b_res->start = min_align;
	b_res->end = size + min_align - 1;
	b_res->flags |= IORESOURCE_STARTALIGN;
	b_res->flags |= mem64_mask;
	return 1;
}

static void pci_bus_size_cardbus(struct pci_bus *bus)
{
	struct pci_dev *bridge = bus->self;
	struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
	u16 ctrl;

	/*
	 * Reserve some resources for CardBus.  We reserve
	 * a fixed amount of bus space for CardBus bridges.
	 */
	b_res[0].start = 0;
	b_res[0].end = pci_cardbus_io_size - 1;
	b_res[0].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;

	b_res[1].start = 0;
	b_res[1].end = pci_cardbus_io_size - 1;
	b_res[1].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;

	/*
	 * Check whether prefetchable memory is supported
	 * by this bridge.
	 */
	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
	if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) {
		ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0;
		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
	}

	/*
	 * If we have prefetchable memory support, allocate
	 * two regions.  Otherwise, allocate one region of
	 * twice the size.
	 */
	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
		b_res[2].start = 0;
		b_res[2].end = pci_cardbus_mem_size - 1;
		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_SIZEALIGN;

		b_res[3].start = 0;
		b_res[3].end = pci_cardbus_mem_size - 1;
		b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
	} else {
		b_res[3].start = 0;
		b_res[3].end = pci_cardbus_mem_size * 2 - 1;
		b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
	}
}

void __ref pci_bus_size_bridges(struct pci_bus *bus)
{
	struct pci_dev *dev;
	unsigned long mask, prefmask;
	resource_size_t min_mem_size = 0, min_io_size = 0;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		struct pci_bus *b = dev->subordinate;
		if (!b)
			continue;

		switch (dev->class >> 8) {
		case PCI_CLASS_BRIDGE_CARDBUS:
			pci_bus_size_cardbus(b);
			break;

		case PCI_CLASS_BRIDGE_PCI:
		default:
			pci_bus_size_bridges(b);
			break;
		}
	}

	/* The root bus? */
	if (!bus->self)
		return;

	switch (bus->self->class >> 8) {
	case PCI_CLASS_BRIDGE_CARDBUS:
		/* don't size cardbuses yet. */
		break;

	case PCI_CLASS_BRIDGE_PCI:
		pci_bridge_check_ranges(bus);
		if (bus->self->is_hotplug_bridge) {
			min_io_size  = pci_hotplug_io_size;
			min_mem_size = pci_hotplug_mem_size;
		}
	default:
		pbus_size_io(bus, min_io_size);
		/* If the bridge supports prefetchable range, size it
		   separately. If it doesn't, or its prefetchable window
		   has already been allocated by arch code, try
		   non-prefetchable range for both types of PCI memory
		   resources. */
		mask = IORESOURCE_MEM;
		prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
		if (pbus_size_mem(bus, prefmask, prefmask, min_mem_size))
			mask = prefmask; /* Success, size non-prefetch only. */
		else
			min_mem_size += min_mem_size;
		pbus_size_mem(bus, mask, IORESOURCE_MEM, min_mem_size);
		break;
	}
}
EXPORT_SYMBOL(pci_bus_size_bridges);

static void __ref __pci_bus_assign_resources(const struct pci_bus *bus,
					 struct resource_list_x *fail_head)
{
	struct pci_bus *b;
	struct pci_dev *dev;

	pbus_assign_resources_sorted(bus, fail_head);

	list_for_each_entry(dev, &bus->devices, bus_list) {
		b = dev->subordinate;
		if (!b)
			continue;

		__pci_bus_assign_resources(b, fail_head);

		switch (dev->class >> 8) {
		case PCI_CLASS_BRIDGE_PCI:
			if (!pci_is_enabled(dev))
				pci_setup_bridge(b);
			break;

		case PCI_CLASS_BRIDGE_CARDBUS:
			pci_setup_cardbus(b);
			break;

		default:
			dev_info(&dev->dev, "not setting up bridge for bus "
				 "%04x:%02x\n", pci_domain_nr(b), b->number);
			break;
		}
	}
}

void __ref pci_bus_assign_resources(const struct pci_bus *bus)
{
	__pci_bus_assign_resources(bus, NULL);
}
EXPORT_SYMBOL(pci_bus_assign_resources);

static void __ref __pci_bridge_assign_resources(const struct pci_dev *bridge,
					 struct resource_list_x *fail_head)
{
	struct pci_bus *b;

	pdev_assign_resources_sorted((struct pci_dev *)bridge, fail_head);

	b = bridge->subordinate;
	if (!b)
		return;

	__pci_bus_assign_resources(b, fail_head);

	switch (bridge->class >> 8) {
	case PCI_CLASS_BRIDGE_PCI:
		pci_setup_bridge(b);
		break;

	case PCI_CLASS_BRIDGE_CARDBUS:
		pci_setup_cardbus(b);
		break;

	default:
		dev_info(&bridge->dev, "not setting up bridge for bus "
			 "%04x:%02x\n", pci_domain_nr(b), b->number);
		break;
	}
}
static void pci_bridge_release_resources(struct pci_bus *bus,
					  unsigned long type)
{
	int idx;
	bool changed = false;
	struct pci_dev *dev;
	struct resource *r;
	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
				  IORESOURCE_PREFETCH;

	dev = bus->self;
	for (idx = PCI_BRIDGE_RESOURCES; idx <= PCI_BRIDGE_RESOURCE_END;
	     idx++) {
		r = &dev->resource[idx];
		if ((r->flags & type_mask) != type)
			continue;
		if (!r->parent)
			continue;
		/*
		 * if there are children under that, we should release them
		 *  all
		 */
		release_child_resources(r);
		if (!release_resource(r)) {
			dev_printk(KERN_DEBUG, &dev->dev,
				 "resource %d %pR released\n", idx, r);
			/* keep the old size */
			r->end = resource_size(r) - 1;
			r->start = 0;
			r->flags = 0;
			changed = true;
		}
	}

	if (changed) {
		/* avoiding touch the one without PREF */
		if (type & IORESOURCE_PREFETCH)
			type = IORESOURCE_PREFETCH;
		__pci_setup_bridge(bus, type);
	}
}

enum release_type {
	leaf_only,
	whole_subtree,
};
/*
 * try to release pci bridge resources that is from leaf bridge,
 * so we can allocate big new one later
 */
static void __ref pci_bus_release_bridge_resources(struct pci_bus *bus,
						   unsigned long type,
						   enum release_type rel_type)
{
	struct pci_dev *dev;
	bool is_leaf_bridge = true;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		struct pci_bus *b = dev->subordinate;
		if (!b)
			continue;

		is_leaf_bridge = false;

		if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
			continue;

		if (rel_type == whole_subtree)
			pci_bus_release_bridge_resources(b, type,
						 whole_subtree);
	}

	if (pci_is_root_bus(bus))
		return;

	if ((bus->self->class >> 8) != PCI_CLASS_BRIDGE_PCI)
		return;

	if ((rel_type == whole_subtree) || is_leaf_bridge)
		pci_bridge_release_resources(bus, type);
}

static void pci_bus_dump_res(struct pci_bus *bus)
{
	struct resource *res;
	int i;

	pci_bus_for_each_resource(bus, res, i) {
		if (!res || !res->end || !res->flags)
                        continue;

		dev_printk(KERN_DEBUG, &bus->dev, "resource %d %pR\n", i, res);
        }
}

static void pci_bus_dump_resources(struct pci_bus *bus)
{
	struct pci_bus *b;
	struct pci_dev *dev;


	pci_bus_dump_res(bus);

	list_for_each_entry(dev, &bus->devices, bus_list) {
		b = dev->subordinate;
		if (!b)
			continue;

		pci_bus_dump_resources(b);
	}
}

void __init
pci_assign_unassigned_resources(void)
{
	struct pci_bus *bus;

	/* Depth first, calculate sizes and alignments of all
	   subordinate buses. */
	list_for_each_entry(bus, &pci_root_buses, node) {
		pci_bus_size_bridges(bus);
	}
	/* Depth last, allocate resources and update the hardware. */
	list_for_each_entry(bus, &pci_root_buses, node) {
		pci_bus_assign_resources(bus);
		pci_enable_bridges(bus);
	}

	/* dump the resource on buses */
	list_for_each_entry(bus, &pci_root_buses, node) {
		pci_bus_dump_resources(bus);
	}
}

void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
{
	struct pci_bus *parent = bridge->subordinate;
	int tried_times = 0;
	struct resource_list_x head, *list;
	int retval;
	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
				  IORESOURCE_PREFETCH;

	head.next = NULL;

again:
	pci_bus_size_bridges(parent);
	__pci_bridge_assign_resources(bridge, &head);
	retval = pci_reenable_device(bridge);
	pci_set_master(bridge);
	pci_enable_bridges(parent);

	tried_times++;

	if (!head.next)
		return;

	if (tried_times >= 2) {
		/* still fail, don't need to try more */
		free_failed_list(&head);
		return;
	}

	printk(KERN_DEBUG "PCI: No. %d try to assign unassigned res\n",
			 tried_times + 1);

	/*
	 * Try to release leaf bridge's resources that doesn't fit resource of
	 * child device under that bridge
	 */
	for (list = head.next; list;) {
		struct pci_bus *bus = list->dev->bus;
		unsigned long flags = list->flags;

		pci_bus_release_bridge_resources(bus, flags & type_mask,
						 whole_subtree);
		list = list->next;
	}
	/* restore size and flags */
	for (list = head.next; list;) {
		struct resource *res = list->res;

		res->start = list->start;
		res->end = list->end;
		res->flags = list->flags;
		if (list->dev->subordinate)
			res->flags = 0;

		list = list->next;
	}
	free_failed_list(&head);

	goto again;
}
EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources);
OpenPOWER on IntegriCloud