aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/pci/setup-bus.c
blob: 5e5191ec8de65931f916c4659e42cf1758e49409 (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
/*
 *	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>


#define DEBUG_CONFIG 1
#if DEBUG_CONFIG
#define DBG(x...)     printk(x)
#else
#define DBG(x...)
#endif

static void pbus_assign_resources_sorted(struct pci_bus *bus)
{
	struct pci_dev *dev;
	struct resource *res;
	struct resource_list head, *list, *tmp;
	int idx;

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

		/* 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))
				continue;
		}

		pdev_sort_resources(dev, &head);
	}

	for (list = head.next; list;) {
		res = list->res;
		idx = res - &list->dev->resource[0];
		if (pci_assign_resource(list->dev, idx)) {
			res->start = 0;
			res->end = 0;
			res->flags = 0;
		}
		tmp = list;
		list = list->next;
		kfree(tmp);
	}
}

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

	printk("PCI: Bus %d, cardbus bridge: %s\n",
		bus->number, pci_name(bridge));

	pcibios_resource_to_bus(bridge, &region, bus->resource[0]);
	if (bus->resource[0]->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.
		 */
		printk("  IO window: %08lx-%08lx\n",
			region.start, region.end);
		pci_write_config_dword(bridge, PCI_CB_IO_BASE_0,
					region.start);
		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0,
					region.end);
	}

	pcibios_resource_to_bus(bridge, &region, bus->resource[1]);
	if (bus->resource[1]->flags & IORESOURCE_IO) {
		printk("  IO window: %08lx-%08lx\n",
			region.start, region.end);
		pci_write_config_dword(bridge, PCI_CB_IO_BASE_1,
					region.start);
		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1,
					region.end);
	}

	pcibios_resource_to_bus(bridge, &region, bus->resource[2]);
	if (bus->resource[2]->flags & IORESOURCE_MEM) {
		printk("  PREFETCH window: %08lx-%08lx\n",
			region.start, region.end);
		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0,
					region.start);
		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0,
					region.end);
	}

	pcibios_resource_to_bus(bridge, &region, bus->resource[3]);
	if (bus->resource[3]->flags & IORESOURCE_MEM) {
		printk("  MEM window: %08lx-%08lx\n",
			region.start, region.end);
		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 __devinit
pci_setup_bridge(struct pci_bus *bus)
{
	struct pci_dev *bridge = bus->self;
	struct pci_bus_region region;
	u32 l, io_upper16;

	DBG(KERN_INFO "PCI: Bridge: %s\n", pci_name(bridge));

	/* Set up the top and bottom of the PCI I/O segment for this bus. */
	pcibios_resource_to_bus(bridge, &region, bus->resource[0]);
	if (bus->resource[0]->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);
		DBG(KERN_INFO "  IO window: %04lx-%04lx\n",
				region.start, region.end);
	}
	else {
		/* Clear upper 16 bits of I/O base/limit. */
		io_upper16 = 0;
		l = 0x00f0;
		DBG(KERN_INFO "  IO window: 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);

	/* Set up the top and bottom of the PCI Memory segment
	   for this bus. */
	pcibios_resource_to_bus(bridge, &region, bus->resource[1]);
	if (bus->resource[1]->flags & IORESOURCE_MEM) {
		l = (region.start >> 16) & 0xfff0;
		l |= region.end & 0xfff00000;
		DBG(KERN_INFO "  MEM window: %08lx-%08lx\n",
				region.start, region.end);
	}
	else {
		l = 0x0000fff0;
		DBG(KERN_INFO "  MEM window: disabled.\n");
	}
	pci_write_config_dword(bridge, PCI_MEMORY_BASE, l);

	/* 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. */
	pcibios_resource_to_bus(bridge, &region, bus->resource[2]);
	if (bus->resource[2]->flags & IORESOURCE_PREFETCH) {
		l = (region.start >> 16) & 0xfff0;
		l |= region.end & 0xfff00000;
		DBG(KERN_INFO "  PREFETCH window: %08lx-%08lx\n",
				region.start, region.end);
	}
	else {
		l = 0x0000fff0;
		DBG(KERN_INFO "  PREFETCH window: disabled.\n");
	}
	pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);

	/* Clear out the upper 32 bits of PREF base. */
	pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, 0);

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

/* 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;
}

/* 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;

	for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
		r = bus->resource[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)
{
	struct pci_dev *dev;
	struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
	unsigned long size = 0, size1 = 0;

	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 = r->end - r->start + 1;

			if (r_size < 0x400)
				/* Might be re-aligned for ISA */
				size += r_size;
			else
				size1 += r_size;
		}
	}
/* 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) {
		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;
}

/* 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)
{
	struct pci_dev *dev;
	unsigned long min_align, align, size;
	unsigned long aligns[12];	/* Alignments from 1Mb to 2Gb */
	int order, max_order;
	struct resource *b_res = find_free_bus_resource(bus, type);

	if (!b_res)
		return 0;

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

	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 & mask) != type)
				continue;
			r_size = r->end - r->start + 1;
			/* For bridges size != alignment */
			align = (i < PCI_BRIDGE_RESOURCES) ? r_size : r->start;
			order = __ffs(align) - 20;
			if (order > 11) {
				printk(KERN_WARNING "PCI: region %s/%d "
				       "too large: %llx-%llx\n",
					pci_name(dev), i,
					(unsigned long long)r->start,
					(unsigned long long)r->end);
				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;
		}
	}

	align = 0;
	min_align = 0;
	for (order = 0; order <= max_order; order++) {
		unsigned long align1 = 1UL << (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) {
		b_res->flags = 0;
		return 1;
	}
	b_res->start = min_align;
	b_res->end = size + min_align - 1;
	return 1;
}

static void __devinit
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 = pci_cardbus_io_size;
	b_res[0].end = b_res[0].start + pci_cardbus_io_size - 1;
	b_res[0].flags |= IORESOURCE_IO;

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

	/*
	 * 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 = pci_cardbus_mem_size;
		b_res[2].end = b_res[2].start + pci_cardbus_mem_size - 1;
		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;

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

void pci_bus_size_bridges(struct pci_bus *bus)
{
	struct pci_dev *dev;
	unsigned long mask, prefmask;

	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);
	default:
		pbus_size_io(bus);
		/* 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))
			mask = prefmask; /* Success, size non-prefetch only. */
		pbus_size_mem(bus, mask, IORESOURCE_MEM);
		break;
	}
}
EXPORT_SYMBOL(pci_bus_size_bridges);

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

	pbus_assign_resources_sorted(bus);

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

		pci_bus_assign_resources(b);

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

		case PCI_CLASS_BRIDGE_CARDBUS:
			pci_setup_cardbus(b);
			break;

		default:
			printk(KERN_INFO "PCI: not setting up bridge %s "
			       "for bus %d\n", pci_name(dev), b->number);
			break;
		}
	}
}
EXPORT_SYMBOL(pci_bus_assign_resources);

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);
	}
}