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>
30 static void pbus_assign_resources_sorted(const struct pci_bus
*bus
)
34 struct resource_list head
, *list
, *tmp
;
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
)
46 /* Don't touch ioapic devices already enabled by firmware */
47 if (class == PCI_CLASS_SYSTEM_PIC
) {
49 pci_read_config_word(dev
, PCI_COMMAND
, &command
);
50 if (command
& (PCI_COMMAND_IO
| PCI_COMMAND_MEMORY
))
54 pdev_sort_resources(dev
, &head
);
57 for (list
= head
.next
; list
;) {
59 idx
= res
- &list
->dev
->resource
[0];
60 if (pci_assign_resource(list
->dev
, idx
)) {
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
, ®ion
, 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
,
90 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_0
,
94 pcibios_resource_to_bus(bridge
, ®ion
, 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
,
101 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_1
,
105 pcibios_resource_to_bus(bridge
, ®ion
, 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
,
112 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_0
,
116 pcibios_resource_to_bus(bridge
, ®ion
, 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
,
123 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_1
,
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
;
147 if (pci_is_enabled(bridge
))
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
, ®ion
, bus
->resource
[0]);
155 if (bus
->resource
[0]->flags
& IORESOURCE_IO
) {
156 pci_read_config_dword(bridge
, PCI_IO_BASE
, &l
);
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
);
167 /* Clear upper 16 bits of I/O base/limit. */
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
181 pcibios_resource_to_bus(bridge
, ®ion
, 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
);
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. */
203 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[2]);
204 if (bus
->resource
[2]->flags
& IORESOURCE_PREFETCH
) {
206 l
= (region
.start
>> 16) & 0xfff0;
207 l
|= region
.end
& 0xfff00000;
208 if (bus
->resource
[2]->flags
& IORESOURCE_MEM_64
) {
210 bu
= upper_32_bits(region
.start
);
211 lu
= upper_32_bits(region
.end
);
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
);
220 dev_info(&bridge
->dev
, " PREFETCH window: disabled\n");
222 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, l
);
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
)
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
);
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);
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)
259 pci_read_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, &pmem
);
261 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
,
263 pci_read_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, &pmem
);
264 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, 0x0);
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
,
277 pci_write_config_dword(bridge
, PCI_PREF_BASE_UPPER32
,
279 pci_read_config_dword(bridge
, PCI_PREF_BASE_UPPER32
, &tmp
);
281 b_res
[2].flags
&= ~IORESOURCE_MEM_64
;
282 pci_write_config_dword(bridge
, PCI_PREF_BASE_UPPER32
,
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
)
295 unsigned long type_mask
= IORESOURCE_IO
| IORESOURCE_MEM
|
298 for (i
= 0; i
< PCI_BUS_NUM_RESOURCES
; i
++) {
299 r
= bus
->resource
[i
];
300 if (r
== &ioport_resource
|| r
== &iomem_resource
)
302 if (r
&& (r
->flags
& type_mask
) == type
) {
306 * if there is no child under that, we should release
307 * and use it. don't need to reset it, pbus_size_* will
310 if (!r
->child
&& !release_resource(r
))
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
)
324 struct resource
*b_res
= find_free_bus_resource(bus
, IORESOURCE_IO
);
325 unsigned long size
= 0, size1
= 0;
330 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
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
))
339 r_size
= resource_size(r
);
342 /* Might be re-aligned for ISA */
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);
355 size
= ALIGN(size
+ size1
, 4096);
360 /* Alignment of the IO window is always 4K */
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
)
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;
381 memset(aligns
, 0, sizeof(aligns
));
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
) {
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
)
397 r_size
= resource_size(r
);
398 /* For bridges size != alignment */
399 align
= pci_resource_alignment(dev
, r
);
400 order
= __ffs(align
) - 20;
402 dev_warn(&dev
->dev
, "BAR %d bad alignment %llx: "
403 "%pR\n", i
, (unsigned long long)align
, r
);
410 /* Exclude ranges with size > align from
411 calculation of the alignment. */
413 aligns
[order
] += align
;
414 if (order
> max_order
)
416 mem64_mask
&= r
->flags
& IORESOURCE_MEM_64
;
424 for (order
= 0; order
<= max_order
; order
++) {
425 resource_size_t align1
= 1;
427 align1
<<= (order
+ 20);
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
);
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
;
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
];
454 * Reserve some resources for CardBus. We reserve
455 * a fixed amount of bus space for CardBus bridges.
458 b_res
[0].end
= pci_cardbus_io_size
- 1;
459 b_res
[0].flags
|= IORESOURCE_IO
| IORESOURCE_SIZEALIGN
;
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
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
481 if (ctrl
& PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
) {
483 b_res
[2].end
= pci_cardbus_mem_size
- 1;
484 b_res
[2].flags
|= IORESOURCE_MEM
| IORESOURCE_PREFETCH
| IORESOURCE_SIZEALIGN
;
487 b_res
[3].end
= pci_cardbus_mem_size
- 1;
488 b_res
[3].flags
|= IORESOURCE_MEM
| IORESOURCE_SIZEALIGN
;
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
)
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
;
507 switch (dev
->class >> 8) {
508 case PCI_CLASS_BRIDGE_CARDBUS
:
509 pci_bus_size_cardbus(b
);
512 case PCI_CLASS_BRIDGE_PCI
:
514 pci_bus_size_bridges(b
);
523 switch (bus
->self
->class >> 8) {
524 case PCI_CLASS_BRIDGE_CARDBUS
:
525 /* don't size cardbuses yet. */
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
;
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
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. */
546 min_mem_size
+= min_mem_size
;
547 pbus_size_mem(bus
, mask
, IORESOURCE_MEM
, min_mem_size
);
551 EXPORT_SYMBOL(pci_bus_size_bridges
);
553 void __ref
pci_bus_assign_resources(const struct pci_bus
*bus
)
558 pbus_assign_resources_sorted(bus
);
560 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
561 b
= dev
->subordinate
;
565 pci_bus_assign_resources(b
);
567 switch (dev
->class >> 8) {
568 case PCI_CLASS_BRIDGE_PCI
:
572 case PCI_CLASS_BRIDGE_CARDBUS
:
573 pci_setup_cardbus(b
);
577 dev_info(&dev
->dev
, "not setting up bridge for bus "
578 "%04x:%02x\n", pci_domain_nr(b
), b
->number
);
583 EXPORT_SYMBOL(pci_bus_assign_resources
);
585 static void pci_bus_dump_res(struct pci_bus
*bus
)
589 for (i
= 0; i
< PCI_BUS_NUM_RESOURCES
; i
++) {
590 struct resource
*res
= bus
->resource
[i
];
591 if (!res
|| !res
->end
)
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:"),
601 static void pci_bus_dump_resources(struct pci_bus
*bus
)
607 pci_bus_dump_res(bus
);
609 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
610 b
= dev
->subordinate
;
614 pci_bus_dump_resources(b
);
619 pci_assign_unassigned_resources(void)
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
);