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 (4096)
44 #define CARDBUS_MEM_SIZE (32*1024*1024)
47 pbus_assign_resources_sorted(struct pci_bus
*bus
)
51 struct resource_list head
, *list
, *tmp
;
54 bus
->bridge_ctl
&= ~PCI_BRIDGE_CTL_VGA
;
57 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
58 u16
class = dev
->class >> 8;
60 /* Don't touch classless devices and host bridges. */
61 if (class == PCI_CLASS_NOT_DEFINED
||
62 class == PCI_CLASS_BRIDGE_HOST
)
65 if (class == PCI_CLASS_DISPLAY_VGA
||
66 class == PCI_CLASS_NOT_DEFINED_VGA
)
67 bus
->bridge_ctl
|= PCI_BRIDGE_CTL_VGA
;
69 pdev_sort_resources(dev
, &head
);
72 for (list
= head
.next
; list
;) {
74 idx
= res
- &list
->dev
->resource
[0];
75 pci_assign_resource(list
->dev
, idx
);
83 pci_setup_cardbus(struct pci_bus
*bus
)
85 struct pci_dev
*bridge
= bus
->self
;
86 struct pci_bus_region region
;
88 printk("PCI: Bus %d, cardbus bridge: %s\n",
89 bus
->number
, pci_name(bridge
));
91 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[0]);
92 if (bus
->resource
[0]->flags
& IORESOURCE_IO
) {
94 * The IO resource is allocated a range twice as large as it
95 * would normally need. This allows us to set both IO regs.
97 printk(" IO window: %08lx-%08lx\n",
98 region
.start
, region
.end
);
99 pci_write_config_dword(bridge
, PCI_CB_IO_BASE_0
,
101 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_0
,
105 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[1]);
106 if (bus
->resource
[1]->flags
& IORESOURCE_IO
) {
107 printk(" IO window: %08lx-%08lx\n",
108 region
.start
, region
.end
);
109 pci_write_config_dword(bridge
, PCI_CB_IO_BASE_1
,
111 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_1
,
115 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[2]);
116 if (bus
->resource
[2]->flags
& IORESOURCE_MEM
) {
117 printk(" PREFETCH window: %08lx-%08lx\n",
118 region
.start
, region
.end
);
119 pci_write_config_dword(bridge
, PCI_CB_MEMORY_BASE_0
,
121 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_0
,
125 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[3]);
126 if (bus
->resource
[3]->flags
& IORESOURCE_MEM
) {
127 printk(" MEM window: %08lx-%08lx\n",
128 region
.start
, region
.end
);
129 pci_write_config_dword(bridge
, PCI_CB_MEMORY_BASE_1
,
131 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_1
,
136 /* Initialize bridges with base/limit values we have collected.
137 PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
138 requires that if there is no I/O ports or memory behind the
139 bridge, corresponding range must be turned off by writing base
140 value greater than limit to the bridge's base/limit registers.
142 Note: care must be taken when updating I/O base/limit registers
143 of bridges which support 32-bit I/O. This update requires two
144 config space writes, so it's quite possible that an I/O window of
145 the bridge will have some undesirable address (e.g. 0) after the
146 first write. Ditto 64-bit prefetchable MMIO. */
147 static void __devinit
148 pci_setup_bridge(struct pci_bus
*bus
)
150 struct pci_dev
*bridge
= bus
->self
;
151 struct pci_bus_region region
;
154 DBG(KERN_INFO
"PCI: Bridge: %s\n", pci_name(bridge
));
156 /* Set up the top and bottom of the PCI I/O segment for this bus. */
157 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[0]);
158 if (bus
->resource
[0]->flags
& IORESOURCE_IO
) {
159 pci_read_config_dword(bridge
, PCI_IO_BASE
, &l
);
161 l
|= (region
.start
>> 8) & 0x00f0;
162 l
|= region
.end
& 0xf000;
163 /* Set up upper 16 bits of I/O base/limit. */
164 io_upper16
= (region
.end
& 0xffff0000) | (region
.start
>> 16);
165 DBG(KERN_INFO
" IO window: %04lx-%04lx\n",
166 region
.start
, region
.end
);
169 /* Clear upper 16 bits of I/O base/limit. */
172 DBG(KERN_INFO
" IO window: disabled.\n");
174 /* Temporarily disable the I/O range before updating PCI_IO_BASE. */
175 pci_write_config_dword(bridge
, PCI_IO_BASE_UPPER16
, 0x0000ffff);
176 /* Update lower 16 bits of I/O base/limit. */
177 pci_write_config_dword(bridge
, PCI_IO_BASE
, l
);
178 /* Update upper 16 bits of I/O base/limit. */
179 pci_write_config_dword(bridge
, PCI_IO_BASE_UPPER16
, io_upper16
);
181 /* Set up the top and bottom of the PCI Memory segment
183 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[1]);
184 if (bus
->resource
[1]->flags
& IORESOURCE_MEM
) {
185 l
= (region
.start
>> 16) & 0xfff0;
186 l
|= region
.end
& 0xfff00000;
187 DBG(KERN_INFO
" MEM window: %08lx-%08lx\n",
188 region
.start
, region
.end
);
192 DBG(KERN_INFO
" MEM window: disabled.\n");
194 pci_write_config_dword(bridge
, PCI_MEMORY_BASE
, l
);
196 /* Clear out the upper 32 bits of PREF limit.
197 If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily
198 disables PREF range, which is ok. */
199 pci_write_config_dword(bridge
, PCI_PREF_LIMIT_UPPER32
, 0);
201 /* Set up PREF base/limit. */
202 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[2]);
203 if (bus
->resource
[2]->flags
& IORESOURCE_PREFETCH
) {
204 l
= (region
.start
>> 16) & 0xfff0;
205 l
|= region
.end
& 0xfff00000;
206 DBG(KERN_INFO
" PREFETCH window: %08lx-%08lx\n",
207 region
.start
, region
.end
);
211 DBG(KERN_INFO
" PREFETCH window: disabled.\n");
213 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, l
);
215 /* Clear out the upper 32 bits of PREF base. */
216 pci_write_config_dword(bridge
, PCI_PREF_BASE_UPPER32
, 0);
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 __devinit
225 pci_bridge_check_ranges(struct pci_bus
*bus
)
229 struct pci_dev
*bridge
= bus
->self
;
230 struct resource
*b_res
;
232 b_res
= &bridge
->resource
[PCI_BRIDGE_RESOURCES
];
233 b_res
[1].flags
|= IORESOURCE_MEM
;
235 pci_read_config_word(bridge
, PCI_IO_BASE
, &io
);
237 pci_write_config_word(bridge
, PCI_IO_BASE
, 0xf0f0);
238 pci_read_config_word(bridge
, PCI_IO_BASE
, &io
);
239 pci_write_config_word(bridge
, PCI_IO_BASE
, 0x0);
242 b_res
[0].flags
|= IORESOURCE_IO
;
243 /* DECchip 21050 pass 2 errata: the bridge may miss an address
244 disconnect boundary by one PCI data phase.
245 Workaround: do not use prefetching on this device. */
246 if (bridge
->vendor
== PCI_VENDOR_ID_DEC
&& bridge
->device
== 0x0001)
248 pci_read_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, &pmem
);
250 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
,
252 pci_read_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, &pmem
);
253 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, 0x0);
256 b_res
[2].flags
|= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
259 /* Helper function for sizing routines: find first available
260 bus resource of a given type. Note: we intentionally skip
261 the bus resources which have already been assigned (that is,
262 have non-NULL parent resource). */
263 static struct resource
* __devinit
264 find_free_bus_resource(struct pci_bus
*bus
, unsigned long type
)
268 unsigned long type_mask
= IORESOURCE_IO
| IORESOURCE_MEM
|
271 for (i
= 0; i
< PCI_BUS_NUM_RESOURCES
; i
++) {
272 r
= bus
->resource
[i
];
273 if (r
&& (r
->flags
& type_mask
) == type
&& !r
->parent
)
279 /* Sizing the IO windows of the PCI-PCI bridge is trivial,
280 since these windows have 4K granularity and the IO ranges
281 of non-bridge PCI devices are limited to 256 bytes.
282 We must be careful with the ISA aliasing though. */
283 static void __devinit
284 pbus_size_io(struct pci_bus
*bus
)
287 struct resource
*b_res
= find_free_bus_resource(bus
, IORESOURCE_IO
);
288 unsigned long size
= 0, size1
= 0;
293 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
296 for (i
= 0; i
< PCI_NUM_RESOURCES
; i
++) {
297 struct resource
*r
= &dev
->resource
[i
];
298 unsigned long r_size
;
300 if (r
->parent
|| !(r
->flags
& IORESOURCE_IO
))
302 r_size
= r
->end
- r
->start
+ 1;
305 /* Might be re-aligned for ISA */
311 /* To be fixed in 2.5: we should have sort of HAVE_ISA
312 flag in the struct pci_bus. */
313 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
314 size
= (size
& 0xff) + ((size
& ~0xffUL
) << 2);
316 size
= ROUND_UP(size
+ size1
, 4096);
321 /* Alignment of the IO window is always 4K */
323 b_res
->end
= b_res
->start
+ size
- 1;
326 /* Calculate the size of the bus and minimal alignment which
327 guarantees that all child resources fit in this size. */
329 pbus_size_mem(struct pci_bus
*bus
, unsigned long mask
, unsigned long type
)
332 unsigned long min_align
, align
, size
;
333 unsigned long aligns
[12]; /* Alignments from 1Mb to 2Gb */
334 int order
, max_order
;
335 struct resource
*b_res
= find_free_bus_resource(bus
, type
);
340 memset(aligns
, 0, sizeof(aligns
));
344 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
347 for (i
= 0; i
< PCI_NUM_RESOURCES
; i
++) {
348 struct resource
*r
= &dev
->resource
[i
];
349 unsigned long r_size
;
351 if (r
->parent
|| (r
->flags
& mask
) != type
)
353 r_size
= r
->end
- r
->start
+ 1;
354 /* For bridges size != alignment */
355 align
= (i
< PCI_BRIDGE_RESOURCES
) ? r_size
: r
->start
;
356 order
= __ffs(align
) - 20;
358 printk(KERN_WARNING
"PCI: region %s/%d "
359 "too large: %lx-%lx\n",
360 pci_name(dev
), i
, r
->start
, r
->end
);
367 /* Exclude ranges with size > align from
368 calculation of the alignment. */
370 aligns
[order
] += align
;
371 if (order
> max_order
)
378 for (order
= 0; order
<= max_order
; order
++) {
379 unsigned long align1
= 1UL << (order
+ 20);
383 else if (ROUND_UP(align
+ min_align
, min_align
) < align1
)
384 min_align
= align1
>> 1;
385 align
+= aligns
[order
];
387 size
= ROUND_UP(size
, min_align
);
392 b_res
->start
= min_align
;
393 b_res
->end
= size
+ min_align
- 1;
397 static void __devinit
398 pci_bus_size_cardbus(struct pci_bus
*bus
)
400 struct pci_dev
*bridge
= bus
->self
;
401 struct resource
*b_res
= &bridge
->resource
[PCI_BRIDGE_RESOURCES
];
405 * Reserve some resources for CardBus. We reserve
406 * a fixed amount of bus space for CardBus bridges.
408 b_res
[0].start
= CARDBUS_IO_SIZE
;
409 b_res
[0].end
= b_res
[0].start
+ CARDBUS_IO_SIZE
- 1;
410 b_res
[0].flags
|= IORESOURCE_IO
;
412 b_res
[1].start
= CARDBUS_IO_SIZE
;
413 b_res
[1].end
= b_res
[1].start
+ CARDBUS_IO_SIZE
- 1;
414 b_res
[1].flags
|= IORESOURCE_IO
;
417 * Check whether prefetchable memory is supported
420 pci_read_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, &ctrl
);
421 if (!(ctrl
& PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
)) {
422 ctrl
|= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
;
423 pci_write_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, ctrl
);
424 pci_read_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, &ctrl
);
428 * If we have prefetchable memory support, allocate
429 * two regions. Otherwise, allocate one region of
432 if (ctrl
& PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
) {
433 b_res
[2].start
= CARDBUS_MEM_SIZE
;
434 b_res
[2].end
= b_res
[2].start
+ CARDBUS_MEM_SIZE
- 1;
435 b_res
[2].flags
|= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
437 b_res
[3].start
= CARDBUS_MEM_SIZE
;
438 b_res
[3].end
= b_res
[3].start
+ CARDBUS_MEM_SIZE
- 1;
439 b_res
[3].flags
|= IORESOURCE_MEM
;
441 b_res
[3].start
= CARDBUS_MEM_SIZE
* 2;
442 b_res
[3].end
= b_res
[3].start
+ CARDBUS_MEM_SIZE
* 2 - 1;
443 b_res
[3].flags
|= IORESOURCE_MEM
;
448 pci_bus_size_bridges(struct pci_bus
*bus
)
451 unsigned long mask
, prefmask
;
453 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
454 struct pci_bus
*b
= dev
->subordinate
;
458 switch (dev
->class >> 8) {
459 case PCI_CLASS_BRIDGE_CARDBUS
:
460 pci_bus_size_cardbus(b
);
463 case PCI_CLASS_BRIDGE_PCI
:
465 pci_bus_size_bridges(b
);
474 switch (bus
->self
->class >> 8) {
475 case PCI_CLASS_BRIDGE_CARDBUS
:
476 /* don't size cardbuses yet. */
479 case PCI_CLASS_BRIDGE_PCI
:
480 pci_bridge_check_ranges(bus
);
483 /* If the bridge supports prefetchable range, size it
484 separately. If it doesn't, or its prefetchable window
485 has already been allocated by arch code, try
486 non-prefetchable range for both types of PCI memory
488 mask
= IORESOURCE_MEM
;
489 prefmask
= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
490 if (pbus_size_mem(bus
, prefmask
, prefmask
))
491 mask
= prefmask
; /* Success, size non-prefetch only. */
492 pbus_size_mem(bus
, mask
, IORESOURCE_MEM
);
496 EXPORT_SYMBOL(pci_bus_size_bridges
);
499 pci_bus_assign_resources(struct pci_bus
*bus
)
504 pbus_assign_resources_sorted(bus
);
506 if (bus
->bridge_ctl
& PCI_BRIDGE_CTL_VGA
) {
507 /* Propagate presence of the VGA to upstream bridges */
508 for (b
= bus
; b
->parent
; b
= b
->parent
) {
509 b
->bridge_ctl
|= PCI_BRIDGE_CTL_VGA
;
512 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
513 b
= dev
->subordinate
;
517 pci_bus_assign_resources(b
);
519 switch (dev
->class >> 8) {
520 case PCI_CLASS_BRIDGE_PCI
:
524 case PCI_CLASS_BRIDGE_CARDBUS
:
525 pci_setup_cardbus(b
);
529 printk(KERN_INFO
"PCI: not setting up bridge %s "
530 "for bus %d\n", pci_name(dev
), b
->number
);
535 EXPORT_SYMBOL(pci_bus_assign_resources
);
538 pci_assign_unassigned_resources(void)
542 /* Depth first, calculate sizes and alignments of all
543 subordinate buses. */
544 list_for_each_entry(bus
, &pci_root_buses
, node
) {
545 pci_bus_size_bridges(bus
);
547 /* Depth last, allocate resources and update the hardware. */
548 list_for_each_entry(bus
, &pci_root_buses
, node
) {
549 pci_bus_assign_resources(bus
);
550 pci_enable_bridges(bus
);