On Tue, Nov 06, 2007 at 02:33:53AM -0800, akpm@linux-foundation.org wrote:
[mmotm.git] / drivers / pci / setup-bus.c
blob0959430534b2daae2c8799827936415dad502075
1 /*
2 * drivers/pci/setup-bus.c
4 * Extruded from code written by
5 * Dave Rusling (david.rusling@reo.mts.dec.com)
6 * David Mosberger (davidm@cs.arizona.edu)
7 * David Miller (davem@redhat.com)
9 * Support routines for initializing a PCI subsystem.
13 * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
14 * PCI-PCI bridges cleanup, sorted resource allocation.
15 * Feb 2002, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
16 * Converted to allocation in 3 passes, which gives
17 * tighter packing. Prefetchable range support.
20 #include <linux/init.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/pci.h>
24 #include <linux/errno.h>
25 #include <linux/ioport.h>
26 #include <linux/cache.h>
27 #include <linux/slab.h>
28 #include "pci.h"
30 static void pbus_assign_resources_sorted(const struct pci_bus *bus)
32 struct pci_dev *dev;
33 struct resource *res;
34 struct resource_list head, *list, *tmp;
35 int idx;
37 head.next = NULL;
38 list_for_each_entry(dev, &bus->devices, bus_list) {
39 u16 class = dev->class >> 8;
41 /* Don't touch classless devices or host bridges or ioapics. */
42 if (class == PCI_CLASS_NOT_DEFINED ||
43 class == PCI_CLASS_BRIDGE_HOST)
44 continue;
46 /* Don't touch ioapic devices already enabled by firmware */
47 if (class == PCI_CLASS_SYSTEM_PIC) {
48 u16 command;
49 pci_read_config_word(dev, PCI_COMMAND, &command);
50 if (command & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY))
51 continue;
54 pdev_sort_resources(dev, &head);
57 for (list = head.next; list;) {
58 res = list->res;
59 idx = res - &list->dev->resource[0];
60 if (pci_assign_resource(list->dev, idx)) {
61 res->start = 0;
62 res->end = 0;
63 res->flags = 0;
65 tmp = list;
66 list = list->next;
67 kfree(tmp);
71 void pci_setup_cardbus(struct pci_bus *bus)
73 struct pci_dev *bridge = bus->self;
74 struct pci_bus_region region;
76 dev_info(&bridge->dev, "CardBus bridge, secondary bus %04x:%02x\n",
77 pci_domain_nr(bus), bus->number);
79 pcibios_resource_to_bus(bridge, &region, bus->resource[0]);
80 if (bus->resource[0]->flags & IORESOURCE_IO) {
82 * The IO resource is allocated a range twice as large as it
83 * would normally need. This allows us to set both IO regs.
85 dev_info(&bridge->dev, " IO window: %#08lx-%#08lx\n",
86 (unsigned long)region.start,
87 (unsigned long)region.end);
88 pci_write_config_dword(bridge, PCI_CB_IO_BASE_0,
89 region.start);
90 pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0,
91 region.end);
94 pcibios_resource_to_bus(bridge, &region, bus->resource[1]);
95 if (bus->resource[1]->flags & IORESOURCE_IO) {
96 dev_info(&bridge->dev, " IO window: %#08lx-%#08lx\n",
97 (unsigned long)region.start,
98 (unsigned long)region.end);
99 pci_write_config_dword(bridge, PCI_CB_IO_BASE_1,
100 region.start);
101 pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1,
102 region.end);
105 pcibios_resource_to_bus(bridge, &region, bus->resource[2]);
106 if (bus->resource[2]->flags & IORESOURCE_MEM) {
107 dev_info(&bridge->dev, " PREFETCH window: %#08lx-%#08lx\n",
108 (unsigned long)region.start,
109 (unsigned long)region.end);
110 pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0,
111 region.start);
112 pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0,
113 region.end);
116 pcibios_resource_to_bus(bridge, &region, bus->resource[3]);
117 if (bus->resource[3]->flags & IORESOURCE_MEM) {
118 dev_info(&bridge->dev, " MEM window: %#08lx-%#08lx\n",
119 (unsigned long)region.start,
120 (unsigned long)region.end);
121 pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_1,
122 region.start);
123 pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_1,
124 region.end);
127 EXPORT_SYMBOL(pci_setup_cardbus);
129 /* Initialize bridges with base/limit values we have collected.
130 PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
131 requires that if there is no I/O ports or memory behind the
132 bridge, corresponding range must be turned off by writing base
133 value greater than limit to the bridge's base/limit registers.
135 Note: care must be taken when updating I/O base/limit registers
136 of bridges which support 32-bit I/O. This update requires two
137 config space writes, so it's quite possible that an I/O window of
138 the bridge will have some undesirable address (e.g. 0) after the
139 first write. Ditto 64-bit prefetchable MMIO. */
140 static void pci_setup_bridge(struct pci_bus *bus)
142 struct pci_dev *bridge = bus->self;
143 struct pci_bus_region region;
144 u32 l, bu, lu, io_upper16;
145 int pref_mem64;
147 if (pci_is_enabled(bridge))
148 return;
150 dev_info(&bridge->dev, "PCI bridge, secondary bus %04x:%02x\n",
151 pci_domain_nr(bus), bus->number);
153 /* Set up the top and bottom of the PCI I/O segment for this bus. */
154 pcibios_resource_to_bus(bridge, &region, bus->resource[0]);
155 if (bus->resource[0]->flags & IORESOURCE_IO) {
156 pci_read_config_dword(bridge, PCI_IO_BASE, &l);
157 l &= 0xffff0000;
158 l |= (region.start >> 8) & 0x00f0;
159 l |= region.end & 0xf000;
160 /* Set up upper 16 bits of I/O base/limit. */
161 io_upper16 = (region.end & 0xffff0000) | (region.start >> 16);
162 dev_info(&bridge->dev, " IO window: %#04lx-%#04lx\n",
163 (unsigned long)region.start,
164 (unsigned long)region.end);
166 else {
167 /* Clear upper 16 bits of I/O base/limit. */
168 io_upper16 = 0;
169 l = 0x00f0;
170 dev_info(&bridge->dev, " IO window: disabled\n");
172 /* Temporarily disable the I/O range before updating PCI_IO_BASE. */
173 pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, 0x0000ffff);
174 /* Update lower 16 bits of I/O base/limit. */
175 pci_write_config_dword(bridge, PCI_IO_BASE, l);
176 /* Update upper 16 bits of I/O base/limit. */
177 pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, io_upper16);
179 /* Set up the top and bottom of the PCI Memory segment
180 for this bus. */
181 pcibios_resource_to_bus(bridge, &region, bus->resource[1]);
182 if (bus->resource[1]->flags & IORESOURCE_MEM) {
183 l = (region.start >> 16) & 0xfff0;
184 l |= region.end & 0xfff00000;
185 dev_info(&bridge->dev, " MEM window: %#08lx-%#08lx\n",
186 (unsigned long)region.start,
187 (unsigned long)region.end);
189 else {
190 l = 0x0000fff0;
191 dev_info(&bridge->dev, " MEM window: disabled\n");
193 pci_write_config_dword(bridge, PCI_MEMORY_BASE, l);
195 /* Clear out the upper 32 bits of PREF limit.
196 If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily
197 disables PREF range, which is ok. */
198 pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0);
200 /* Set up PREF base/limit. */
201 pref_mem64 = 0;
202 bu = lu = 0;
203 pcibios_resource_to_bus(bridge, &region, bus->resource[2]);
204 if (bus->resource[2]->flags & IORESOURCE_PREFETCH) {
205 int width = 8;
206 l = (region.start >> 16) & 0xfff0;
207 l |= region.end & 0xfff00000;
208 if (bus->resource[2]->flags & IORESOURCE_MEM_64) {
209 pref_mem64 = 1;
210 bu = upper_32_bits(region.start);
211 lu = upper_32_bits(region.end);
212 width = 16;
214 dev_info(&bridge->dev, " PREFETCH window: %#0*llx-%#0*llx\n",
215 width, (unsigned long long)region.start,
216 width, (unsigned long long)region.end);
218 else {
219 l = 0x0000fff0;
220 dev_info(&bridge->dev, " PREFETCH window: disabled\n");
222 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);
224 if (pref_mem64) {
225 /* Set the upper 32 bits of PREF base & limit. */
226 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu);
227 pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu);
230 pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl);
233 /* Check whether the bridge supports optional I/O and
234 prefetchable memory ranges. If not, the respective
235 base/limit registers must be read-only and read as 0. */
236 static void pci_bridge_check_ranges(struct pci_bus *bus)
238 u16 io;
239 u32 pmem;
240 struct pci_dev *bridge = bus->self;
241 struct resource *b_res;
243 b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
244 b_res[1].flags |= IORESOURCE_MEM;
246 pci_read_config_word(bridge, PCI_IO_BASE, &io);
247 if (!io) {
248 pci_write_config_word(bridge, PCI_IO_BASE, 0xf0f0);
249 pci_read_config_word(bridge, PCI_IO_BASE, &io);
250 pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
252 if (io)
253 b_res[0].flags |= IORESOURCE_IO;
254 /* DECchip 21050 pass 2 errata: the bridge may miss an address
255 disconnect boundary by one PCI data phase.
256 Workaround: do not use prefetching on this device. */
257 if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
258 return;
259 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
260 if (!pmem) {
261 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
262 0xfff0fff0);
263 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
264 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
266 if (pmem) {
267 b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
268 if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64)
269 b_res[2].flags |= IORESOURCE_MEM_64;
272 /* double check if bridge does support 64 bit pref */
273 if (b_res[2].flags & IORESOURCE_MEM_64) {
274 u32 mem_base_hi, tmp;
275 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32,
276 &mem_base_hi);
277 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
278 0xffffffff);
279 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp);
280 if (!tmp)
281 b_res[2].flags &= ~IORESOURCE_MEM_64;
282 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
283 mem_base_hi);
287 /* Helper function for sizing routines: find first available
288 bus resource of a given type. Note: we intentionally skip
289 the bus resources which have already been assigned (that is,
290 have non-NULL parent resource). */
291 static struct resource *find_free_bus_resource(struct pci_bus *bus, unsigned long type)
293 int i;
294 struct resource *r;
295 unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
296 IORESOURCE_PREFETCH;
298 for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
299 r = bus->resource[i];
300 if (r == &ioport_resource || r == &iomem_resource)
301 continue;
302 if (r && (r->flags & type_mask) == type) {
303 if (!r->parent)
304 return r;
306 * if there is no child under that, we should release
307 * and use it. don't need to reset it, pbus_size_* will
308 * set it again
310 if (!r->child && !release_resource(r))
311 return r;
314 return NULL;
317 /* Sizing the IO windows of the PCI-PCI bridge is trivial,
318 since these windows have 4K granularity and the IO ranges
319 of non-bridge PCI devices are limited to 256 bytes.
320 We must be careful with the ISA aliasing though. */
321 static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size)
323 struct pci_dev *dev;
324 struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
325 unsigned long size = 0, size1 = 0;
327 if (!b_res)
328 return;
330 list_for_each_entry(dev, &bus->devices, bus_list) {
331 int i;
333 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
334 struct resource *r = &dev->resource[i];
335 unsigned long r_size;
337 if (r->parent || !(r->flags & IORESOURCE_IO))
338 continue;
339 r_size = resource_size(r);
341 if (r_size < 0x400)
342 /* Might be re-aligned for ISA */
343 size += r_size;
344 else
345 size1 += r_size;
348 if (size < min_size)
349 size = min_size;
350 /* To be fixed in 2.5: we should have sort of HAVE_ISA
351 flag in the struct pci_bus. */
352 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
353 size = (size & 0xff) + ((size & ~0xffUL) << 2);
354 #endif
355 size = ALIGN(size + size1, 4096);
356 if (!size) {
357 b_res->flags = 0;
358 return;
360 /* Alignment of the IO window is always 4K */
361 b_res->start = 4096;
362 b_res->end = b_res->start + size - 1;
363 b_res->flags |= IORESOURCE_STARTALIGN;
366 /* Calculate the size of the bus and minimal alignment which
367 guarantees that all child resources fit in this size. */
368 static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
369 unsigned long type, resource_size_t min_size)
371 struct pci_dev *dev;
372 resource_size_t min_align, align, size;
373 resource_size_t aligns[12]; /* Alignments from 1Mb to 2Gb */
374 int order, max_order;
375 struct resource *b_res = find_free_bus_resource(bus, type);
376 unsigned int mem64_mask = 0;
378 if (!b_res)
379 return 0;
381 memset(aligns, 0, sizeof(aligns));
382 max_order = 0;
383 size = 0;
385 mem64_mask = b_res->flags & IORESOURCE_MEM_64;
386 b_res->flags &= ~IORESOURCE_MEM_64;
388 list_for_each_entry(dev, &bus->devices, bus_list) {
389 int i;
391 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
392 struct resource *r = &dev->resource[i];
393 resource_size_t r_size;
395 if (r->parent || (r->flags & mask) != type)
396 continue;
397 r_size = resource_size(r);
398 /* For bridges size != alignment */
399 align = pci_resource_alignment(dev, r);
400 order = __ffs(align) - 20;
401 if (order > 11) {
402 dev_warn(&dev->dev, "BAR %d bad alignment %llx: "
403 "%pR\n", i, (unsigned long long)align, r);
404 r->flags = 0;
405 continue;
407 size += r_size;
408 if (order < 0)
409 order = 0;
410 /* Exclude ranges with size > align from
411 calculation of the alignment. */
412 if (r_size == align)
413 aligns[order] += align;
414 if (order > max_order)
415 max_order = order;
416 mem64_mask &= r->flags & IORESOURCE_MEM_64;
419 if (size < min_size)
420 size = min_size;
422 align = 0;
423 min_align = 0;
424 for (order = 0; order <= max_order; order++) {
425 resource_size_t align1 = 1;
427 align1 <<= (order + 20);
429 if (!align)
430 min_align = align1;
431 else if (ALIGN(align + min_align, min_align) < align1)
432 min_align = align1 >> 1;
433 align += aligns[order];
435 size = ALIGN(size, min_align);
436 if (!size) {
437 b_res->flags = 0;
438 return 1;
440 b_res->start = min_align;
441 b_res->end = size + min_align - 1;
442 b_res->flags |= IORESOURCE_STARTALIGN;
443 b_res->flags |= mem64_mask;
444 return 1;
447 static void pci_bus_size_cardbus(struct pci_bus *bus)
449 struct pci_dev *bridge = bus->self;
450 struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
451 u16 ctrl;
454 * Reserve some resources for CardBus. We reserve
455 * a fixed amount of bus space for CardBus bridges.
457 b_res[0].start = 0;
458 b_res[0].end = pci_cardbus_io_size - 1;
459 b_res[0].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
461 b_res[1].start = 0;
462 b_res[1].end = pci_cardbus_io_size - 1;
463 b_res[1].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
466 * Check whether prefetchable memory is supported
467 * by this bridge.
469 pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
470 if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) {
471 ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0;
472 pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
473 pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
477 * If we have prefetchable memory support, allocate
478 * two regions. Otherwise, allocate one region of
479 * twice the size.
481 if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
482 b_res[2].start = 0;
483 b_res[2].end = pci_cardbus_mem_size - 1;
484 b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_SIZEALIGN;
486 b_res[3].start = 0;
487 b_res[3].end = pci_cardbus_mem_size - 1;
488 b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
489 } else {
490 b_res[3].start = 0;
491 b_res[3].end = pci_cardbus_mem_size * 2 - 1;
492 b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
496 void __ref pci_bus_size_bridges(struct pci_bus *bus)
498 struct pci_dev *dev;
499 unsigned long mask, prefmask;
500 resource_size_t min_mem_size = 0, min_io_size = 0;
502 list_for_each_entry(dev, &bus->devices, bus_list) {
503 struct pci_bus *b = dev->subordinate;
504 if (!b)
505 continue;
507 switch (dev->class >> 8) {
508 case PCI_CLASS_BRIDGE_CARDBUS:
509 pci_bus_size_cardbus(b);
510 break;
512 case PCI_CLASS_BRIDGE_PCI:
513 default:
514 pci_bus_size_bridges(b);
515 break;
519 /* The root bus? */
520 if (!bus->self)
521 return;
523 switch (bus->self->class >> 8) {
524 case PCI_CLASS_BRIDGE_CARDBUS:
525 /* don't size cardbuses yet. */
526 break;
528 case PCI_CLASS_BRIDGE_PCI:
529 pci_bridge_check_ranges(bus);
530 if (bus->self->is_hotplug_bridge) {
531 min_io_size = pci_hotplug_io_size;
532 min_mem_size = pci_hotplug_mem_size;
534 default:
535 pbus_size_io(bus, min_io_size);
536 /* If the bridge supports prefetchable range, size it
537 separately. If it doesn't, or its prefetchable window
538 has already been allocated by arch code, try
539 non-prefetchable range for both types of PCI memory
540 resources. */
541 mask = IORESOURCE_MEM;
542 prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
543 if (pbus_size_mem(bus, prefmask, prefmask, min_mem_size))
544 mask = prefmask; /* Success, size non-prefetch only. */
545 else
546 min_mem_size += min_mem_size;
547 pbus_size_mem(bus, mask, IORESOURCE_MEM, min_mem_size);
548 break;
551 EXPORT_SYMBOL(pci_bus_size_bridges);
553 void __ref pci_bus_assign_resources(const struct pci_bus *bus)
555 struct pci_bus *b;
556 struct pci_dev *dev;
558 pbus_assign_resources_sorted(bus);
560 list_for_each_entry(dev, &bus->devices, bus_list) {
561 b = dev->subordinate;
562 if (!b)
563 continue;
565 pci_bus_assign_resources(b);
567 switch (dev->class >> 8) {
568 case PCI_CLASS_BRIDGE_PCI:
569 pci_setup_bridge(b);
570 break;
572 case PCI_CLASS_BRIDGE_CARDBUS:
573 pci_setup_cardbus(b);
574 break;
576 default:
577 dev_info(&dev->dev, "not setting up bridge for bus "
578 "%04x:%02x\n", pci_domain_nr(b), b->number);
579 break;
583 EXPORT_SYMBOL(pci_bus_assign_resources);
585 static void pci_bus_dump_res(struct pci_bus *bus)
587 int i;
589 for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
590 struct resource *res = bus->resource[i];
591 if (!res || !res->end)
592 continue;
594 dev_printk(KERN_DEBUG, &bus->dev, "resource %d %s %pR\n", i,
595 (res->flags & IORESOURCE_IO) ? "io: " :
596 ((res->flags & IORESOURCE_PREFETCH)? "pref mem":"mem:"),
597 res);
601 static void pci_bus_dump_resources(struct pci_bus *bus)
603 struct pci_bus *b;
604 struct pci_dev *dev;
607 pci_bus_dump_res(bus);
609 list_for_each_entry(dev, &bus->devices, bus_list) {
610 b = dev->subordinate;
611 if (!b)
612 continue;
614 pci_bus_dump_resources(b);
618 void __init
619 pci_assign_unassigned_resources(void)
621 struct pci_bus *bus;
623 /* Depth first, calculate sizes and alignments of all
624 subordinate buses. */
625 list_for_each_entry(bus, &pci_root_buses, node) {
626 pci_bus_size_bridges(bus);
628 /* Depth last, allocate resources and update the hardware. */
629 list_for_each_entry(bus, &pci_root_buses, node) {
630 pci_bus_assign_resources(bus);
631 pci_enable_bridges(bus);
634 /* dump the resource on buses */
635 list_for_each_entry(bus, &pci_root_buses, node) {
636 pci_bus_dump_resources(bus);