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 #define DEBUG_CONFIG 1
32 #define DBG(x...) printk(x)
37 #define ROUND_UP(x, a) (((x) + (a) - 1) & ~((a) - 1))
40 * FIXME: IO should be max 256 bytes. However, since we may
41 * have a P2P bridge below a cardbus bridge, we need 4K.
43 #define CARDBUS_IO_SIZE (256)
44 #define CARDBUS_MEM_SIZE (64*1024*1024)
47 pbus_assign_resources_sorted(struct pci_bus
*bus
)
51 struct resource_list head
, *list
, *tmp
;
55 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
56 u16
class = dev
->class >> 8;
58 /* Don't touch classless devices or host bridges or ioapics. */
59 if (class == PCI_CLASS_NOT_DEFINED
||
60 class == PCI_CLASS_BRIDGE_HOST
)
63 /* Don't touch ioapic devices already enabled by firmware */
64 if (class == PCI_CLASS_SYSTEM_PIC
) {
66 pci_read_config_word(dev
, PCI_COMMAND
, &command
);
67 if (command
& (PCI_COMMAND_IO
| PCI_COMMAND_MEMORY
))
71 pdev_sort_resources(dev
, &head
);
74 for (list
= head
.next
; list
;) {
76 idx
= res
- &list
->dev
->resource
[0];
77 if (pci_assign_resource(list
->dev
, idx
)) {
88 void pci_setup_cardbus(struct pci_bus
*bus
)
90 struct pci_dev
*bridge
= bus
->self
;
91 struct pci_bus_region region
;
93 printk("PCI: Bus %d, cardbus bridge: %s\n",
94 bus
->number
, pci_name(bridge
));
96 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[0]);
97 if (bus
->resource
[0]->flags
& IORESOURCE_IO
) {
99 * The IO resource is allocated a range twice as large as it
100 * would normally need. This allows us to set both IO regs.
102 printk(" IO window: %08lx-%08lx\n",
103 region
.start
, region
.end
);
104 pci_write_config_dword(bridge
, PCI_CB_IO_BASE_0
,
106 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_0
,
110 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[1]);
111 if (bus
->resource
[1]->flags
& IORESOURCE_IO
) {
112 printk(" IO window: %08lx-%08lx\n",
113 region
.start
, region
.end
);
114 pci_write_config_dword(bridge
, PCI_CB_IO_BASE_1
,
116 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_1
,
120 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[2]);
121 if (bus
->resource
[2]->flags
& IORESOURCE_MEM
) {
122 printk(" PREFETCH window: %08lx-%08lx\n",
123 region
.start
, region
.end
);
124 pci_write_config_dword(bridge
, PCI_CB_MEMORY_BASE_0
,
126 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_0
,
130 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[3]);
131 if (bus
->resource
[3]->flags
& IORESOURCE_MEM
) {
132 printk(" MEM window: %08lx-%08lx\n",
133 region
.start
, region
.end
);
134 pci_write_config_dword(bridge
, PCI_CB_MEMORY_BASE_1
,
136 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_1
,
140 EXPORT_SYMBOL(pci_setup_cardbus
);
142 /* Initialize bridges with base/limit values we have collected.
143 PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
144 requires that if there is no I/O ports or memory behind the
145 bridge, corresponding range must be turned off by writing base
146 value greater than limit to the bridge's base/limit registers.
148 Note: care must be taken when updating I/O base/limit registers
149 of bridges which support 32-bit I/O. This update requires two
150 config space writes, so it's quite possible that an I/O window of
151 the bridge will have some undesirable address (e.g. 0) after the
152 first write. Ditto 64-bit prefetchable MMIO. */
153 static void __devinit
154 pci_setup_bridge(struct pci_bus
*bus
)
156 struct pci_dev
*bridge
= bus
->self
;
157 struct pci_bus_region region
;
160 DBG(KERN_INFO
"PCI: Bridge: %s\n", pci_name(bridge
));
162 /* Set up the top and bottom of the PCI I/O segment for this bus. */
163 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[0]);
164 if (bus
->resource
[0]->flags
& IORESOURCE_IO
) {
165 pci_read_config_dword(bridge
, PCI_IO_BASE
, &l
);
167 l
|= (region
.start
>> 8) & 0x00f0;
168 l
|= region
.end
& 0xf000;
169 /* Set up upper 16 bits of I/O base/limit. */
170 io_upper16
= (region
.end
& 0xffff0000) | (region
.start
>> 16);
171 DBG(KERN_INFO
" IO window: %04lx-%04lx\n",
172 region
.start
, region
.end
);
175 /* Clear upper 16 bits of I/O base/limit. */
178 DBG(KERN_INFO
" IO window: disabled.\n");
180 /* Temporarily disable the I/O range before updating PCI_IO_BASE. */
181 pci_write_config_dword(bridge
, PCI_IO_BASE_UPPER16
, 0x0000ffff);
182 /* Update lower 16 bits of I/O base/limit. */
183 pci_write_config_dword(bridge
, PCI_IO_BASE
, l
);
184 /* Update upper 16 bits of I/O base/limit. */
185 pci_write_config_dword(bridge
, PCI_IO_BASE_UPPER16
, io_upper16
);
187 /* Set up the top and bottom of the PCI Memory segment
189 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[1]);
190 if (bus
->resource
[1]->flags
& IORESOURCE_MEM
) {
191 l
= (region
.start
>> 16) & 0xfff0;
192 l
|= region
.end
& 0xfff00000;
193 DBG(KERN_INFO
" MEM window: %08lx-%08lx\n",
194 region
.start
, region
.end
);
198 DBG(KERN_INFO
" MEM window: disabled.\n");
200 pci_write_config_dword(bridge
, PCI_MEMORY_BASE
, l
);
202 /* Clear out the upper 32 bits of PREF limit.
203 If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily
204 disables PREF range, which is ok. */
205 pci_write_config_dword(bridge
, PCI_PREF_LIMIT_UPPER32
, 0);
207 /* Set up PREF base/limit. */
208 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[2]);
209 if (bus
->resource
[2]->flags
& IORESOURCE_PREFETCH
) {
210 l
= (region
.start
>> 16) & 0xfff0;
211 l
|= region
.end
& 0xfff00000;
212 DBG(KERN_INFO
" PREFETCH window: %08lx-%08lx\n",
213 region
.start
, region
.end
);
217 DBG(KERN_INFO
" PREFETCH window: disabled.\n");
219 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, l
);
221 /* Clear out the upper 32 bits of PREF base. */
222 pci_write_config_dword(bridge
, PCI_PREF_BASE_UPPER32
, 0);
224 pci_write_config_word(bridge
, PCI_BRIDGE_CONTROL
, bus
->bridge_ctl
);
227 /* Check whether the bridge supports optional I/O and
228 prefetchable memory ranges. If not, the respective
229 base/limit registers must be read-only and read as 0. */
230 static void __devinit
231 pci_bridge_check_ranges(struct pci_bus
*bus
)
235 struct pci_dev
*bridge
= bus
->self
;
236 struct resource
*b_res
;
238 b_res
= &bridge
->resource
[PCI_BRIDGE_RESOURCES
];
239 b_res
[1].flags
|= IORESOURCE_MEM
;
241 pci_read_config_word(bridge
, PCI_IO_BASE
, &io
);
243 pci_write_config_word(bridge
, PCI_IO_BASE
, 0xf0f0);
244 pci_read_config_word(bridge
, PCI_IO_BASE
, &io
);
245 pci_write_config_word(bridge
, PCI_IO_BASE
, 0x0);
248 b_res
[0].flags
|= IORESOURCE_IO
;
249 /* DECchip 21050 pass 2 errata: the bridge may miss an address
250 disconnect boundary by one PCI data phase.
251 Workaround: do not use prefetching on this device. */
252 if (bridge
->vendor
== PCI_VENDOR_ID_DEC
&& bridge
->device
== 0x0001)
254 pci_read_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, &pmem
);
256 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
,
258 pci_read_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, &pmem
);
259 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, 0x0);
262 b_res
[2].flags
|= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
265 /* Helper function for sizing routines: find first available
266 bus resource of a given type. Note: we intentionally skip
267 the bus resources which have already been assigned (that is,
268 have non-NULL parent resource). */
269 static struct resource
* __devinit
270 find_free_bus_resource(struct pci_bus
*bus
, unsigned long type
)
274 unsigned long type_mask
= IORESOURCE_IO
| IORESOURCE_MEM
|
277 for (i
= 0; i
< PCI_BUS_NUM_RESOURCES
; i
++) {
278 r
= bus
->resource
[i
];
279 if (r
== &ioport_resource
|| r
== &iomem_resource
)
281 if (r
&& (r
->flags
& type_mask
) == type
&& !r
->parent
)
287 /* Sizing the IO windows of the PCI-PCI bridge is trivial,
288 since these windows have 4K granularity and the IO ranges
289 of non-bridge PCI devices are limited to 256 bytes.
290 We must be careful with the ISA aliasing though. */
291 static void __devinit
292 pbus_size_io(struct pci_bus
*bus
)
295 struct resource
*b_res
= find_free_bus_resource(bus
, IORESOURCE_IO
);
296 unsigned long size
= 0, size1
= 0;
301 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
304 for (i
= 0; i
< PCI_NUM_RESOURCES
; i
++) {
305 struct resource
*r
= &dev
->resource
[i
];
306 unsigned long r_size
;
308 if (r
->parent
|| !(r
->flags
& IORESOURCE_IO
))
310 r_size
= r
->end
- r
->start
+ 1;
313 /* Might be re-aligned for ISA */
319 /* To be fixed in 2.5: we should have sort of HAVE_ISA
320 flag in the struct pci_bus. */
321 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
322 size
= (size
& 0xff) + ((size
& ~0xffUL
) << 2);
324 size
= ROUND_UP(size
+ size1
, 4096);
329 /* Alignment of the IO window is always 4K */
331 b_res
->end
= b_res
->start
+ size
- 1;
334 /* Calculate the size of the bus and minimal alignment which
335 guarantees that all child resources fit in this size. */
337 pbus_size_mem(struct pci_bus
*bus
, unsigned long mask
, unsigned long type
)
340 unsigned long min_align
, align
, size
;
341 unsigned long aligns
[12]; /* Alignments from 1Mb to 2Gb */
342 int order
, max_order
;
343 struct resource
*b_res
= find_free_bus_resource(bus
, type
);
348 memset(aligns
, 0, sizeof(aligns
));
352 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
355 for (i
= 0; i
< PCI_NUM_RESOURCES
; i
++) {
356 struct resource
*r
= &dev
->resource
[i
];
357 unsigned long r_size
;
359 if (r
->parent
|| (r
->flags
& mask
) != type
)
361 r_size
= r
->end
- r
->start
+ 1;
362 /* For bridges size != alignment */
363 align
= (i
< PCI_BRIDGE_RESOURCES
) ? r_size
: r
->start
;
364 order
= __ffs(align
) - 20;
366 printk(KERN_WARNING
"PCI: region %s/%d "
367 "too large: %llx-%llx\n",
369 (unsigned long long)r
->start
,
370 (unsigned long long)r
->end
);
377 /* Exclude ranges with size > align from
378 calculation of the alignment. */
380 aligns
[order
] += align
;
381 if (order
> max_order
)
388 for (order
= 0; order
<= max_order
; order
++) {
389 unsigned long align1
= 1UL << (order
+ 20);
393 else if (ROUND_UP(align
+ min_align
, min_align
) < align1
)
394 min_align
= align1
>> 1;
395 align
+= aligns
[order
];
397 size
= ROUND_UP(size
, min_align
);
402 b_res
->start
= min_align
;
403 b_res
->end
= size
+ min_align
- 1;
407 static void __devinit
408 pci_bus_size_cardbus(struct pci_bus
*bus
)
410 struct pci_dev
*bridge
= bus
->self
;
411 struct resource
*b_res
= &bridge
->resource
[PCI_BRIDGE_RESOURCES
];
415 * Reserve some resources for CardBus. We reserve
416 * a fixed amount of bus space for CardBus bridges.
418 b_res
[0].start
= CARDBUS_IO_SIZE
;
419 b_res
[0].end
= b_res
[0].start
+ CARDBUS_IO_SIZE
- 1;
420 b_res
[0].flags
|= IORESOURCE_IO
;
422 b_res
[1].start
= CARDBUS_IO_SIZE
;
423 b_res
[1].end
= b_res
[1].start
+ CARDBUS_IO_SIZE
- 1;
424 b_res
[1].flags
|= IORESOURCE_IO
;
427 * Check whether prefetchable memory is supported
430 pci_read_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, &ctrl
);
431 if (!(ctrl
& PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
)) {
432 ctrl
|= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
;
433 pci_write_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, ctrl
);
434 pci_read_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, &ctrl
);
438 * If we have prefetchable memory support, allocate
439 * two regions. Otherwise, allocate one region of
442 if (ctrl
& PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
) {
443 b_res
[2].start
= CARDBUS_MEM_SIZE
;
444 b_res
[2].end
= b_res
[2].start
+ CARDBUS_MEM_SIZE
- 1;
445 b_res
[2].flags
|= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
447 b_res
[3].start
= CARDBUS_MEM_SIZE
;
448 b_res
[3].end
= b_res
[3].start
+ CARDBUS_MEM_SIZE
- 1;
449 b_res
[3].flags
|= IORESOURCE_MEM
;
451 b_res
[3].start
= CARDBUS_MEM_SIZE
* 2;
452 b_res
[3].end
= b_res
[3].start
+ CARDBUS_MEM_SIZE
* 2 - 1;
453 b_res
[3].flags
|= IORESOURCE_MEM
;
458 pci_bus_size_bridges(struct pci_bus
*bus
)
461 unsigned long mask
, prefmask
;
463 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
464 struct pci_bus
*b
= dev
->subordinate
;
468 switch (dev
->class >> 8) {
469 case PCI_CLASS_BRIDGE_CARDBUS
:
470 pci_bus_size_cardbus(b
);
473 case PCI_CLASS_BRIDGE_PCI
:
475 pci_bus_size_bridges(b
);
484 switch (bus
->self
->class >> 8) {
485 case PCI_CLASS_BRIDGE_CARDBUS
:
486 /* don't size cardbuses yet. */
489 case PCI_CLASS_BRIDGE_PCI
:
490 pci_bridge_check_ranges(bus
);
493 /* If the bridge supports prefetchable range, size it
494 separately. If it doesn't, or its prefetchable window
495 has already been allocated by arch code, try
496 non-prefetchable range for both types of PCI memory
498 mask
= IORESOURCE_MEM
;
499 prefmask
= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
500 if (pbus_size_mem(bus
, prefmask
, prefmask
))
501 mask
= prefmask
; /* Success, size non-prefetch only. */
502 pbus_size_mem(bus
, mask
, IORESOURCE_MEM
);
506 EXPORT_SYMBOL(pci_bus_size_bridges
);
509 pci_bus_assign_resources(struct pci_bus
*bus
)
514 pbus_assign_resources_sorted(bus
);
516 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
517 b
= dev
->subordinate
;
521 pci_bus_assign_resources(b
);
523 switch (dev
->class >> 8) {
524 case PCI_CLASS_BRIDGE_PCI
:
528 case PCI_CLASS_BRIDGE_CARDBUS
:
529 pci_setup_cardbus(b
);
533 printk(KERN_INFO
"PCI: not setting up bridge %s "
534 "for bus %d\n", pci_name(dev
), b
->number
);
539 EXPORT_SYMBOL(pci_bus_assign_resources
);
542 pci_assign_unassigned_resources(void)
546 /* Depth first, calculate sizes and alignments of all
547 subordinate buses. */
548 list_for_each_entry(bus
, &pci_root_buses
, node
) {
549 pci_bus_size_bridges(bus
);
551 /* Depth last, allocate resources and update the hardware. */
552 list_for_each_entry(bus
, &pci_root_buses
, node
) {
553 pci_bus_assign_resources(bus
);
554 pci_enable_bridges(bus
);