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
;
75 struct pci_bus_region region
;
77 dev_info(&bridge
->dev
, "CardBus bridge to [bus %02x-%02x]\n",
78 bus
->secondary
, bus
->subordinate
);
80 res
= bus
->resource
[0];
81 pcibios_resource_to_bus(bridge
, ®ion
, res
);
82 if (res
->flags
& IORESOURCE_IO
) {
84 * The IO resource is allocated a range twice as large as it
85 * would normally need. This allows us to set both IO regs.
87 dev_info(&bridge
->dev
, " bridge window %pR\n", res
);
88 pci_write_config_dword(bridge
, PCI_CB_IO_BASE_0
,
90 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_0
,
94 res
= bus
->resource
[1];
95 pcibios_resource_to_bus(bridge
, ®ion
, res
);
96 if (res
->flags
& IORESOURCE_IO
) {
97 dev_info(&bridge
->dev
, " bridge window %pR\n", res
);
98 pci_write_config_dword(bridge
, PCI_CB_IO_BASE_1
,
100 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_1
,
104 res
= bus
->resource
[2];
105 pcibios_resource_to_bus(bridge
, ®ion
, res
);
106 if (res
->flags
& IORESOURCE_MEM
) {
107 dev_info(&bridge
->dev
, " bridge window %pR\n", res
);
108 pci_write_config_dword(bridge
, PCI_CB_MEMORY_BASE_0
,
110 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_0
,
114 res
= bus
->resource
[3];
115 pcibios_resource_to_bus(bridge
, ®ion
, res
);
116 if (res
->flags
& IORESOURCE_MEM
) {
117 dev_info(&bridge
->dev
, " bridge window %pR\n", res
);
118 pci_write_config_dword(bridge
, PCI_CB_MEMORY_BASE_1
,
120 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_1
,
124 EXPORT_SYMBOL(pci_setup_cardbus
);
126 /* Initialize bridges with base/limit values we have collected.
127 PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
128 requires that if there is no I/O ports or memory behind the
129 bridge, corresponding range must be turned off by writing base
130 value greater than limit to the bridge's base/limit registers.
132 Note: care must be taken when updating I/O base/limit registers
133 of bridges which support 32-bit I/O. This update requires two
134 config space writes, so it's quite possible that an I/O window of
135 the bridge will have some undesirable address (e.g. 0) after the
136 first write. Ditto 64-bit prefetchable MMIO. */
137 static void pci_setup_bridge(struct pci_bus
*bus
)
139 struct pci_dev
*bridge
= bus
->self
;
140 struct resource
*res
;
141 struct pci_bus_region region
;
142 u32 l
, bu
, lu
, io_upper16
;
144 if (pci_is_enabled(bridge
))
147 dev_info(&bridge
->dev
, "PCI bridge to [bus %02x-%02x]\n",
148 bus
->secondary
, bus
->subordinate
);
150 /* Set up the top and bottom of the PCI I/O segment for this bus. */
151 res
= bus
->resource
[0];
152 pcibios_resource_to_bus(bridge
, ®ion
, res
);
153 if (res
->flags
& IORESOURCE_IO
) {
154 pci_read_config_dword(bridge
, PCI_IO_BASE
, &l
);
156 l
|= (region
.start
>> 8) & 0x00f0;
157 l
|= region
.end
& 0xf000;
158 /* Set up upper 16 bits of I/O base/limit. */
159 io_upper16
= (region
.end
& 0xffff0000) | (region
.start
>> 16);
160 dev_info(&bridge
->dev
, " bridge window %pR\n", res
);
163 /* Clear upper 16 bits of I/O base/limit. */
166 dev_info(&bridge
->dev
, " bridge window [io disabled]\n");
168 /* Temporarily disable the I/O range before updating PCI_IO_BASE. */
169 pci_write_config_dword(bridge
, PCI_IO_BASE_UPPER16
, 0x0000ffff);
170 /* Update lower 16 bits of I/O base/limit. */
171 pci_write_config_dword(bridge
, PCI_IO_BASE
, l
);
172 /* Update upper 16 bits of I/O base/limit. */
173 pci_write_config_dword(bridge
, PCI_IO_BASE_UPPER16
, io_upper16
);
175 /* Set up the top and bottom of the PCI Memory segment
177 res
= bus
->resource
[1];
178 pcibios_resource_to_bus(bridge
, ®ion
, res
);
179 if (res
->flags
& IORESOURCE_MEM
) {
180 l
= (region
.start
>> 16) & 0xfff0;
181 l
|= region
.end
& 0xfff00000;
182 dev_info(&bridge
->dev
, " bridge window %pR\n", res
);
186 dev_info(&bridge
->dev
, " bridge window [mem disabled]\n");
188 pci_write_config_dword(bridge
, PCI_MEMORY_BASE
, l
);
190 /* Clear out the upper 32 bits of PREF limit.
191 If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily
192 disables PREF range, which is ok. */
193 pci_write_config_dword(bridge
, PCI_PREF_LIMIT_UPPER32
, 0);
195 /* Set up PREF base/limit. */
197 res
= bus
->resource
[2];
198 pcibios_resource_to_bus(bridge
, ®ion
, res
);
199 if (res
->flags
& IORESOURCE_PREFETCH
) {
200 l
= (region
.start
>> 16) & 0xfff0;
201 l
|= region
.end
& 0xfff00000;
202 if (res
->flags
& IORESOURCE_MEM_64
) {
203 bu
= upper_32_bits(region
.start
);
204 lu
= upper_32_bits(region
.end
);
206 dev_info(&bridge
->dev
, " bridge window %pR\n", res
);
210 dev_info(&bridge
->dev
, " bridge window [mem pref disabled]\n");
212 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, l
);
214 /* Set the upper 32 bits of PREF base & limit. */
215 pci_write_config_dword(bridge
, PCI_PREF_BASE_UPPER32
, bu
);
216 pci_write_config_dword(bridge
, PCI_PREF_LIMIT_UPPER32
, lu
);
218 pci_write_config_word(bridge
, PCI_BRIDGE_CONTROL
, bus
->bridge_ctl
);
221 /* Check whether the bridge supports optional I/O and
222 prefetchable memory ranges. If not, the respective
223 base/limit registers must be read-only and read as 0. */
224 static void pci_bridge_check_ranges(struct pci_bus
*bus
)
228 struct pci_dev
*bridge
= bus
->self
;
229 struct resource
*b_res
;
231 b_res
= &bridge
->resource
[PCI_BRIDGE_RESOURCES
];
232 b_res
[1].flags
|= IORESOURCE_MEM
;
234 pci_read_config_word(bridge
, PCI_IO_BASE
, &io
);
236 pci_write_config_word(bridge
, PCI_IO_BASE
, 0xf0f0);
237 pci_read_config_word(bridge
, PCI_IO_BASE
, &io
);
238 pci_write_config_word(bridge
, PCI_IO_BASE
, 0x0);
241 b_res
[0].flags
|= IORESOURCE_IO
;
242 /* DECchip 21050 pass 2 errata: the bridge may miss an address
243 disconnect boundary by one PCI data phase.
244 Workaround: do not use prefetching on this device. */
245 if (bridge
->vendor
== PCI_VENDOR_ID_DEC
&& bridge
->device
== 0x0001)
247 pci_read_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, &pmem
);
249 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
,
251 pci_read_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, &pmem
);
252 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, 0x0);
255 b_res
[2].flags
|= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
256 if ((pmem
& PCI_PREF_RANGE_TYPE_MASK
) == PCI_PREF_RANGE_TYPE_64
)
257 b_res
[2].flags
|= IORESOURCE_MEM_64
;
260 /* double check if bridge does support 64 bit pref */
261 if (b_res
[2].flags
& IORESOURCE_MEM_64
) {
262 u32 mem_base_hi
, tmp
;
263 pci_read_config_dword(bridge
, PCI_PREF_BASE_UPPER32
,
265 pci_write_config_dword(bridge
, PCI_PREF_BASE_UPPER32
,
267 pci_read_config_dword(bridge
, PCI_PREF_BASE_UPPER32
, &tmp
);
269 b_res
[2].flags
&= ~IORESOURCE_MEM_64
;
270 pci_write_config_dword(bridge
, PCI_PREF_BASE_UPPER32
,
275 /* Helper function for sizing routines: find first available
276 bus resource of a given type. Note: we intentionally skip
277 the bus resources which have already been assigned (that is,
278 have non-NULL parent resource). */
279 static struct resource
*find_free_bus_resource(struct pci_bus
*bus
, unsigned long type
)
283 unsigned long type_mask
= IORESOURCE_IO
| IORESOURCE_MEM
|
286 for (i
= 0; i
< PCI_BUS_NUM_RESOURCES
; i
++) {
287 r
= bus
->resource
[i
];
288 if (r
== &ioport_resource
|| r
== &iomem_resource
)
290 if (r
&& (r
->flags
& type_mask
) == type
&& !r
->parent
)
296 /* Sizing the IO windows of the PCI-PCI bridge is trivial,
297 since these windows have 4K granularity and the IO ranges
298 of non-bridge PCI devices are limited to 256 bytes.
299 We must be careful with the ISA aliasing though. */
300 static void pbus_size_io(struct pci_bus
*bus
, resource_size_t min_size
)
303 struct resource
*b_res
= find_free_bus_resource(bus
, IORESOURCE_IO
);
304 unsigned long size
= 0, size1
= 0;
309 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
312 for (i
= 0; i
< PCI_NUM_RESOURCES
; i
++) {
313 struct resource
*r
= &dev
->resource
[i
];
314 unsigned long r_size
;
316 if (r
->parent
|| !(r
->flags
& IORESOURCE_IO
))
318 r_size
= resource_size(r
);
321 /* Might be re-aligned for ISA */
329 /* To be fixed in 2.5: we should have sort of HAVE_ISA
330 flag in the struct pci_bus. */
331 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
332 size
= (size
& 0xff) + ((size
& ~0xffUL
) << 2);
334 size
= ALIGN(size
+ size1
, 4096);
336 if (b_res
->start
|| b_res
->end
)
337 dev_info(&bus
->self
->dev
, "disabling bridge window "
338 "%pR to [bus %02x-%02x] (unused)\n", b_res
,
339 bus
->secondary
, bus
->subordinate
);
343 /* Alignment of the IO window is always 4K */
345 b_res
->end
= b_res
->start
+ size
- 1;
346 b_res
->flags
|= IORESOURCE_STARTALIGN
;
349 /* Calculate the size of the bus and minimal alignment which
350 guarantees that all child resources fit in this size. */
351 static int pbus_size_mem(struct pci_bus
*bus
, unsigned long mask
,
352 unsigned long type
, resource_size_t min_size
)
355 resource_size_t min_align
, align
, size
;
356 resource_size_t aligns
[12]; /* Alignments from 1Mb to 2Gb */
357 int order
, max_order
;
358 struct resource
*b_res
= find_free_bus_resource(bus
, type
);
359 unsigned int mem64_mask
= 0;
364 memset(aligns
, 0, sizeof(aligns
));
368 mem64_mask
= b_res
->flags
& IORESOURCE_MEM_64
;
369 b_res
->flags
&= ~IORESOURCE_MEM_64
;
371 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
374 for (i
= 0; i
< PCI_NUM_RESOURCES
; i
++) {
375 struct resource
*r
= &dev
->resource
[i
];
376 resource_size_t r_size
;
378 if (r
->parent
|| (r
->flags
& mask
) != type
)
380 r_size
= resource_size(r
);
381 /* For bridges size != alignment */
382 align
= pci_resource_alignment(dev
, r
);
383 order
= __ffs(align
) - 20;
385 dev_warn(&dev
->dev
, "disabling BAR %d: %pR "
386 "(bad alignment %#llx)\n", i
, r
,
387 (unsigned long long) align
);
394 /* Exclude ranges with size > align from
395 calculation of the alignment. */
397 aligns
[order
] += align
;
398 if (order
> max_order
)
400 mem64_mask
&= r
->flags
& IORESOURCE_MEM_64
;
408 for (order
= 0; order
<= max_order
; order
++) {
409 resource_size_t align1
= 1;
411 align1
<<= (order
+ 20);
415 else if (ALIGN(align
+ min_align
, min_align
) < align1
)
416 min_align
= align1
>> 1;
417 align
+= aligns
[order
];
419 size
= ALIGN(size
, min_align
);
421 if (b_res
->start
|| b_res
->end
)
422 dev_info(&bus
->self
->dev
, "disabling bridge window "
423 "%pR to [bus %02x-%02x] (unused)\n", b_res
,
424 bus
->secondary
, bus
->subordinate
);
428 b_res
->start
= min_align
;
429 b_res
->end
= size
+ min_align
- 1;
430 b_res
->flags
|= IORESOURCE_STARTALIGN
;
431 b_res
->flags
|= mem64_mask
;
435 static void pci_bus_size_cardbus(struct pci_bus
*bus
)
437 struct pci_dev
*bridge
= bus
->self
;
438 struct resource
*b_res
= &bridge
->resource
[PCI_BRIDGE_RESOURCES
];
442 * Reserve some resources for CardBus. We reserve
443 * a fixed amount of bus space for CardBus bridges.
446 b_res
[0].end
= pci_cardbus_io_size
- 1;
447 b_res
[0].flags
|= IORESOURCE_IO
| IORESOURCE_SIZEALIGN
;
450 b_res
[1].end
= pci_cardbus_io_size
- 1;
451 b_res
[1].flags
|= IORESOURCE_IO
| IORESOURCE_SIZEALIGN
;
454 * Check whether prefetchable memory is supported
457 pci_read_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, &ctrl
);
458 if (!(ctrl
& PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
)) {
459 ctrl
|= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
;
460 pci_write_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, ctrl
);
461 pci_read_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, &ctrl
);
465 * If we have prefetchable memory support, allocate
466 * two regions. Otherwise, allocate one region of
469 if (ctrl
& PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
) {
471 b_res
[2].end
= pci_cardbus_mem_size
- 1;
472 b_res
[2].flags
|= IORESOURCE_MEM
| IORESOURCE_PREFETCH
| IORESOURCE_SIZEALIGN
;
475 b_res
[3].end
= pci_cardbus_mem_size
- 1;
476 b_res
[3].flags
|= IORESOURCE_MEM
| IORESOURCE_SIZEALIGN
;
479 b_res
[3].end
= pci_cardbus_mem_size
* 2 - 1;
480 b_res
[3].flags
|= IORESOURCE_MEM
| IORESOURCE_SIZEALIGN
;
484 void __ref
pci_bus_size_bridges(struct pci_bus
*bus
)
487 unsigned long mask
, prefmask
;
488 resource_size_t min_mem_size
= 0, min_io_size
= 0;
490 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
491 struct pci_bus
*b
= dev
->subordinate
;
495 switch (dev
->class >> 8) {
496 case PCI_CLASS_BRIDGE_CARDBUS
:
497 pci_bus_size_cardbus(b
);
500 case PCI_CLASS_BRIDGE_PCI
:
502 pci_bus_size_bridges(b
);
511 switch (bus
->self
->class >> 8) {
512 case PCI_CLASS_BRIDGE_CARDBUS
:
513 /* don't size cardbuses yet. */
516 case PCI_CLASS_BRIDGE_PCI
:
517 pci_bridge_check_ranges(bus
);
518 if (bus
->self
->is_hotplug_bridge
) {
519 min_io_size
= pci_hotplug_io_size
;
520 min_mem_size
= pci_hotplug_mem_size
;
523 pbus_size_io(bus
, min_io_size
);
524 /* If the bridge supports prefetchable range, size it
525 separately. If it doesn't, or its prefetchable window
526 has already been allocated by arch code, try
527 non-prefetchable range for both types of PCI memory
529 mask
= IORESOURCE_MEM
;
530 prefmask
= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
531 if (pbus_size_mem(bus
, prefmask
, prefmask
, min_mem_size
))
532 mask
= prefmask
; /* Success, size non-prefetch only. */
534 min_mem_size
+= min_mem_size
;
535 pbus_size_mem(bus
, mask
, IORESOURCE_MEM
, min_mem_size
);
539 EXPORT_SYMBOL(pci_bus_size_bridges
);
541 void __ref
pci_bus_assign_resources(const struct pci_bus
*bus
)
546 pbus_assign_resources_sorted(bus
);
548 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
549 b
= dev
->subordinate
;
553 pci_bus_assign_resources(b
);
555 switch (dev
->class >> 8) {
556 case PCI_CLASS_BRIDGE_PCI
:
560 case PCI_CLASS_BRIDGE_CARDBUS
:
561 pci_setup_cardbus(b
);
565 dev_info(&dev
->dev
, "not setting up bridge for bus "
566 "%04x:%02x\n", pci_domain_nr(b
), b
->number
);
571 EXPORT_SYMBOL(pci_bus_assign_resources
);
573 static void pci_bus_dump_res(struct pci_bus
*bus
)
577 for (i
= 0; i
< PCI_BUS_NUM_RESOURCES
; i
++) {
578 struct resource
*res
= bus
->resource
[i
];
579 if (!res
|| !res
->end
)
582 dev_printk(KERN_DEBUG
, &bus
->dev
, "resource %d %pR\n", i
, res
);
586 static void pci_bus_dump_resources(struct pci_bus
*bus
)
592 pci_bus_dump_res(bus
);
594 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
595 b
= dev
->subordinate
;
599 pci_bus_dump_resources(b
);
604 pci_assign_unassigned_resources(void)
608 /* Depth first, calculate sizes and alignments of all
609 subordinate buses. */
610 list_for_each_entry(bus
, &pci_root_buses
, node
) {
611 pci_bus_size_bridges(bus
);
613 /* Depth last, allocate resources and update the hardware. */
614 list_for_each_entry(bus
, &pci_root_buses
, node
) {
615 pci_bus_assign_resources(bus
);
616 pci_enable_bridges(bus
);
619 /* dump the resource on buses */
620 list_for_each_entry(bus
, &pci_root_buses
, node
) {
621 pci_bus_dump_resources(bus
);