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Merge commit 'v2.6.32-rc5' into perf/probes
[karo-tx-linux.git] / drivers / pci / setup-bus.c
1 /*
2  *      drivers/pci/setup-bus.c
3  *
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)
8  *
9  * Support routines for initializing a PCI subsystem.
10  */
11
12 /*
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.
18  */
19
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"
29
30 static void pbus_assign_resources_sorted(const struct pci_bus *bus)
31 {
32         struct pci_dev *dev;
33         struct resource *res;
34         struct resource_list head, *list, *tmp;
35         int idx;
36
37         head.next = NULL;
38         list_for_each_entry(dev, &bus->devices, bus_list) {
39                 u16 class = dev->class >> 8;
40
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;
45
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;
52                 }
53
54                 pdev_sort_resources(dev, &head);
55         }
56
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;
64                 }
65                 tmp = list;
66                 list = list->next;
67                 kfree(tmp);
68         }
69 }
70
71 void pci_setup_cardbus(struct pci_bus *bus)
72 {
73         struct pci_dev *bridge = bus->self;
74         struct pci_bus_region region;
75
76         dev_info(&bridge->dev, "CardBus bridge, secondary bus %04x:%02x\n",
77                  pci_domain_nr(bus), bus->number);
78
79         pcibios_resource_to_bus(bridge, &region, bus->resource[0]);
80         if (bus->resource[0]->flags & IORESOURCE_IO) {
81                 /*
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.
84                  */
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);
92         }
93
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);
103         }
104
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);
114         }
115
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);
125         }
126 }
127 EXPORT_SYMBOL(pci_setup_cardbus);
128
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.
134
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)
141 {
142         struct pci_dev *bridge = bus->self;
143         struct pci_bus_region region;
144         u32 l, bu, lu, io_upper16;
145         int pref_mem64;
146
147         if (pci_is_enabled(bridge))
148                 return;
149
150         dev_info(&bridge->dev, "PCI bridge, secondary bus %04x:%02x\n",
151                  pci_domain_nr(bus), bus->number);
152
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);
165         }
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");
171         }
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);
178
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);
188         }
189         else {
190                 l = 0x0000fff0;
191                 dev_info(&bridge->dev, "  MEM window: disabled\n");
192         }
193         pci_write_config_dword(bridge, PCI_MEMORY_BASE, l);
194
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);
199
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;
213                 }
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);
217         }
218         else {
219                 l = 0x0000fff0;
220                 dev_info(&bridge->dev, "  PREFETCH window: disabled\n");
221         }
222         pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);
223
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);
228         }
229
230         pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl);
231 }
232
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)
237 {
238         u16 io;
239         u32 pmem;
240         struct pci_dev *bridge = bus->self;
241         struct resource *b_res;
242
243         b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
244         b_res[1].flags |= IORESOURCE_MEM;
245
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);
251         }
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);
265         }
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;
270         }
271
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);
284         }
285 }
286
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)
292 {
293         int i;
294         struct resource *r;
295         unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
296                                   IORESOURCE_PREFETCH;
297
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;
305                         /*
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
309                          */
310                         if (!r->child && !release_resource(r))
311                                 return r;
312                 }
313         }
314         return NULL;
315 }
316
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)
322 {
323         struct pci_dev *dev;
324         struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
325         unsigned long size = 0, size1 = 0;
326
327         if (!b_res)
328                 return;
329
330         list_for_each_entry(dev, &bus->devices, bus_list) {
331                 int i;
332
333                 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
334                         struct resource *r = &dev->resource[i];
335                         unsigned long r_size;
336
337                         if (r->parent || !(r->flags & IORESOURCE_IO))
338                                 continue;
339                         r_size = resource_size(r);
340
341                         if (r_size < 0x400)
342                                 /* Might be re-aligned for ISA */
343                                 size += r_size;
344                         else
345                                 size1 += r_size;
346                 }
347         }
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;
359         }
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;
364 }
365
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)
370 {
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;
377
378         if (!b_res)
379                 return 0;
380
381         memset(aligns, 0, sizeof(aligns));
382         max_order = 0;
383         size = 0;
384
385         mem64_mask = b_res->flags & IORESOURCE_MEM_64;
386         b_res->flags &= ~IORESOURCE_MEM_64;
387
388         list_for_each_entry(dev, &bus->devices, bus_list) {
389                 int i;
390
391                 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
392                         struct resource *r = &dev->resource[i];
393                         resource_size_t r_size;
394
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;
406                         }
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;
417                 }
418         }
419         if (size < min_size)
420                 size = min_size;
421
422         align = 0;
423         min_align = 0;
424         for (order = 0; order <= max_order; order++) {
425                 resource_size_t align1 = 1;
426
427                 align1 <<= (order + 20);
428
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];
434         }
435         size = ALIGN(size, min_align);
436         if (!size) {
437                 b_res->flags = 0;
438                 return 1;
439         }
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;
445 }
446
447 static void pci_bus_size_cardbus(struct pci_bus *bus)
448 {
449         struct pci_dev *bridge = bus->self;
450         struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
451         u16 ctrl;
452
453         /*
454          * Reserve some resources for CardBus.  We reserve
455          * a fixed amount of bus space for CardBus bridges.
456          */
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;
460
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;
464
465         /*
466          * Check whether prefetchable memory is supported
467          * by this bridge.
468          */
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);
474         }
475
476         /*
477          * If we have prefetchable memory support, allocate
478          * two regions.  Otherwise, allocate one region of
479          * twice the size.
480          */
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;
485
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;
493         }
494 }
495
496 void __ref pci_bus_size_bridges(struct pci_bus *bus)
497 {
498         struct pci_dev *dev;
499         unsigned long mask, prefmask;
500         resource_size_t min_mem_size = 0, min_io_size = 0;
501
502         list_for_each_entry(dev, &bus->devices, bus_list) {
503                 struct pci_bus *b = dev->subordinate;
504                 if (!b)
505                         continue;
506
507                 switch (dev->class >> 8) {
508                 case PCI_CLASS_BRIDGE_CARDBUS:
509                         pci_bus_size_cardbus(b);
510                         break;
511
512                 case PCI_CLASS_BRIDGE_PCI:
513                 default:
514                         pci_bus_size_bridges(b);
515                         break;
516                 }
517         }
518
519         /* The root bus? */
520         if (!bus->self)
521                 return;
522
523         switch (bus->self->class >> 8) {
524         case PCI_CLASS_BRIDGE_CARDBUS:
525                 /* don't size cardbuses yet. */
526                 break;
527
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;
533                 }
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;
549         }
550 }
551 EXPORT_SYMBOL(pci_bus_size_bridges);
552
553 void __ref pci_bus_assign_resources(const struct pci_bus *bus)
554 {
555         struct pci_bus *b;
556         struct pci_dev *dev;
557
558         pbus_assign_resources_sorted(bus);
559
560         list_for_each_entry(dev, &bus->devices, bus_list) {
561                 b = dev->subordinate;
562                 if (!b)
563                         continue;
564
565                 pci_bus_assign_resources(b);
566
567                 switch (dev->class >> 8) {
568                 case PCI_CLASS_BRIDGE_PCI:
569                         pci_setup_bridge(b);
570                         break;
571
572                 case PCI_CLASS_BRIDGE_CARDBUS:
573                         pci_setup_cardbus(b);
574                         break;
575
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;
580                 }
581         }
582 }
583 EXPORT_SYMBOL(pci_bus_assign_resources);
584
585 static void pci_bus_dump_res(struct pci_bus *bus)
586 {
587         int i;
588
589         for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
590                 struct resource *res = bus->resource[i];
591                 if (!res || !res->end)
592                         continue;
593
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);
598         }
599 }
600
601 static void pci_bus_dump_resources(struct pci_bus *bus)
602 {
603         struct pci_bus *b;
604         struct pci_dev *dev;
605
606
607         pci_bus_dump_res(bus);
608
609         list_for_each_entry(dev, &bus->devices, bus_list) {
610                 b = dev->subordinate;
611                 if (!b)
612                         continue;
613
614                 pci_bus_dump_resources(b);
615         }
616 }
617
618 void __init
619 pci_assign_unassigned_resources(void)
620 {
621         struct pci_bus *bus;
622
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);
627         }
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);
632         }
633
634         /* dump the resource on buses */
635         list_for_each_entry(bus, &pci_root_buses, node) {
636                 pci_bus_dump_resources(bus);
637         }
638 }