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 (32*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
||
61 class == PCI_CLASS_SYSTEM_PIC
)
64 pdev_sort_resources(dev
, &head
);
67 for (list
= head
.next
; list
;) {
69 idx
= res
- &list
->dev
->resource
[0];
70 if (pci_assign_resource(list
->dev
, idx
)) {
81 void pci_setup_cardbus(struct pci_bus
*bus
)
83 struct pci_dev
*bridge
= bus
->self
;
84 struct pci_bus_region region
;
86 printk("PCI: Bus %d, cardbus bridge: %s\n",
87 bus
->number
, pci_name(bridge
));
89 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[0]);
90 if (bus
->resource
[0]->flags
& IORESOURCE_IO
) {
92 * The IO resource is allocated a range twice as large as it
93 * would normally need. This allows us to set both IO regs.
95 printk(" IO window: %08lx-%08lx\n",
96 region
.start
, region
.end
);
97 pci_write_config_dword(bridge
, PCI_CB_IO_BASE_0
,
99 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_0
,
103 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[1]);
104 if (bus
->resource
[1]->flags
& IORESOURCE_IO
) {
105 printk(" IO window: %08lx-%08lx\n",
106 region
.start
, region
.end
);
107 pci_write_config_dword(bridge
, PCI_CB_IO_BASE_1
,
109 pci_write_config_dword(bridge
, PCI_CB_IO_LIMIT_1
,
113 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[2]);
114 if (bus
->resource
[2]->flags
& IORESOURCE_MEM
) {
115 printk(" PREFETCH window: %08lx-%08lx\n",
116 region
.start
, region
.end
);
117 pci_write_config_dword(bridge
, PCI_CB_MEMORY_BASE_0
,
119 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_0
,
123 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[3]);
124 if (bus
->resource
[3]->flags
& IORESOURCE_MEM
) {
125 printk(" MEM window: %08lx-%08lx\n",
126 region
.start
, region
.end
);
127 pci_write_config_dword(bridge
, PCI_CB_MEMORY_BASE_1
,
129 pci_write_config_dword(bridge
, PCI_CB_MEMORY_LIMIT_1
,
133 EXPORT_SYMBOL(pci_setup_cardbus
);
135 /* Initialize bridges with base/limit values we have collected.
136 PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
137 requires that if there is no I/O ports or memory behind the
138 bridge, corresponding range must be turned off by writing base
139 value greater than limit to the bridge's base/limit registers.
141 Note: care must be taken when updating I/O base/limit registers
142 of bridges which support 32-bit I/O. This update requires two
143 config space writes, so it's quite possible that an I/O window of
144 the bridge will have some undesirable address (e.g. 0) after the
145 first write. Ditto 64-bit prefetchable MMIO. */
146 static void __devinit
147 pci_setup_bridge(struct pci_bus
*bus
)
149 struct pci_dev
*bridge
= bus
->self
;
150 struct pci_bus_region region
;
153 DBG(KERN_INFO
"PCI: Bridge: %s\n", pci_name(bridge
));
155 /* Set up the top and bottom of the PCI I/O segment for this bus. */
156 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[0]);
157 if (bus
->resource
[0]->flags
& IORESOURCE_IO
) {
158 pci_read_config_dword(bridge
, PCI_IO_BASE
, &l
);
160 l
|= (region
.start
>> 8) & 0x00f0;
161 l
|= region
.end
& 0xf000;
162 /* Set up upper 16 bits of I/O base/limit. */
163 io_upper16
= (region
.end
& 0xffff0000) | (region
.start
>> 16);
164 DBG(KERN_INFO
" IO window: %04lx-%04lx\n",
165 region
.start
, region
.end
);
168 /* Clear upper 16 bits of I/O base/limit. */
171 DBG(KERN_INFO
" IO window: disabled.\n");
173 /* Temporarily disable the I/O range before updating PCI_IO_BASE. */
174 pci_write_config_dword(bridge
, PCI_IO_BASE_UPPER16
, 0x0000ffff);
175 /* Update lower 16 bits of I/O base/limit. */
176 pci_write_config_dword(bridge
, PCI_IO_BASE
, l
);
177 /* Update upper 16 bits of I/O base/limit. */
178 pci_write_config_dword(bridge
, PCI_IO_BASE_UPPER16
, io_upper16
);
180 /* Set up the top and bottom of the PCI Memory segment
182 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[1]);
183 if (bus
->resource
[1]->flags
& IORESOURCE_MEM
) {
184 l
= (region
.start
>> 16) & 0xfff0;
185 l
|= region
.end
& 0xfff00000;
186 DBG(KERN_INFO
" MEM window: %08lx-%08lx\n",
187 region
.start
, region
.end
);
191 DBG(KERN_INFO
" 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. */
201 pcibios_resource_to_bus(bridge
, ®ion
, bus
->resource
[2]);
202 if (bus
->resource
[2]->flags
& IORESOURCE_PREFETCH
) {
203 l
= (region
.start
>> 16) & 0xfff0;
204 l
|= region
.end
& 0xfff00000;
205 DBG(KERN_INFO
" PREFETCH window: %08lx-%08lx\n",
206 region
.start
, region
.end
);
210 DBG(KERN_INFO
" PREFETCH window: disabled.\n");
212 pci_write_config_dword(bridge
, PCI_PREF_MEMORY_BASE
, l
);
214 /* Clear out the upper 32 bits of PREF base. */
215 pci_write_config_dword(bridge
, PCI_PREF_BASE_UPPER32
, 0);
217 pci_write_config_word(bridge
, PCI_BRIDGE_CONTROL
, bus
->bridge_ctl
);
220 /* Check whether the bridge supports optional I/O and
221 prefetchable memory ranges. If not, the respective
222 base/limit registers must be read-only and read as 0. */
223 static void __devinit
224 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
;
258 /* Helper function for sizing routines: find first available
259 bus resource of a given type. Note: we intentionally skip
260 the bus resources which have already been assigned (that is,
261 have non-NULL parent resource). */
262 static struct resource
* __devinit
263 find_free_bus_resource(struct pci_bus
*bus
, unsigned long type
)
267 unsigned long type_mask
= IORESOURCE_IO
| IORESOURCE_MEM
|
270 for (i
= 0; i
< PCI_BUS_NUM_RESOURCES
; i
++) {
271 r
= bus
->resource
[i
];
272 if (r
== &ioport_resource
|| r
== &iomem_resource
)
274 if (r
&& (r
->flags
& type_mask
) == type
&& !r
->parent
)
280 /* Sizing the IO windows of the PCI-PCI bridge is trivial,
281 since these windows have 4K granularity and the IO ranges
282 of non-bridge PCI devices are limited to 256 bytes.
283 We must be careful with the ISA aliasing though. */
284 static void __devinit
285 pbus_size_io(struct pci_bus
*bus
)
288 struct resource
*b_res
= find_free_bus_resource(bus
, IORESOURCE_IO
);
289 unsigned long size
= 0, size1
= 0;
294 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
297 for (i
= 0; i
< PCI_NUM_RESOURCES
; i
++) {
298 struct resource
*r
= &dev
->resource
[i
];
299 unsigned long r_size
;
301 if (r
->parent
|| !(r
->flags
& IORESOURCE_IO
))
303 r_size
= r
->end
- r
->start
+ 1;
306 /* Might be re-aligned for ISA */
312 /* To be fixed in 2.5: we should have sort of HAVE_ISA
313 flag in the struct pci_bus. */
314 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
315 size
= (size
& 0xff) + ((size
& ~0xffUL
) << 2);
317 size
= ROUND_UP(size
+ size1
, 4096);
322 /* Alignment of the IO window is always 4K */
324 b_res
->end
= b_res
->start
+ size
- 1;
327 /* Calculate the size of the bus and minimal alignment which
328 guarantees that all child resources fit in this size. */
330 pbus_size_mem(struct pci_bus
*bus
, unsigned long mask
, unsigned long type
)
333 unsigned long min_align
, align
, size
;
334 unsigned long aligns
[12]; /* Alignments from 1Mb to 2Gb */
335 int order
, max_order
;
336 struct resource
*b_res
= find_free_bus_resource(bus
, type
);
341 memset(aligns
, 0, sizeof(aligns
));
345 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
348 for (i
= 0; i
< PCI_NUM_RESOURCES
; i
++) {
349 struct resource
*r
= &dev
->resource
[i
];
350 unsigned long r_size
;
352 if (r
->parent
|| (r
->flags
& mask
) != type
)
354 r_size
= r
->end
- r
->start
+ 1;
355 /* For bridges size != alignment */
356 align
= (i
< PCI_BRIDGE_RESOURCES
) ? r_size
: r
->start
;
357 order
= __ffs(align
) - 20;
359 printk(KERN_WARNING
"PCI: region %s/%d "
360 "too large: %lx-%lx\n",
361 pci_name(dev
), i
, r
->start
, r
->end
);
368 /* Exclude ranges with size > align from
369 calculation of the alignment. */
371 aligns
[order
] += align
;
372 if (order
> max_order
)
379 for (order
= 0; order
<= max_order
; order
++) {
380 unsigned long align1
= 1UL << (order
+ 20);
384 else if (ROUND_UP(align
+ min_align
, min_align
) < align1
)
385 min_align
= align1
>> 1;
386 align
+= aligns
[order
];
388 size
= ROUND_UP(size
, min_align
);
393 b_res
->start
= min_align
;
394 b_res
->end
= size
+ min_align
- 1;
398 static void __devinit
399 pci_bus_size_cardbus(struct pci_bus
*bus
)
401 struct pci_dev
*bridge
= bus
->self
;
402 struct resource
*b_res
= &bridge
->resource
[PCI_BRIDGE_RESOURCES
];
406 * Reserve some resources for CardBus. We reserve
407 * a fixed amount of bus space for CardBus bridges.
409 b_res
[0].start
= CARDBUS_IO_SIZE
;
410 b_res
[0].end
= b_res
[0].start
+ CARDBUS_IO_SIZE
- 1;
411 b_res
[0].flags
|= IORESOURCE_IO
;
413 b_res
[1].start
= CARDBUS_IO_SIZE
;
414 b_res
[1].end
= b_res
[1].start
+ CARDBUS_IO_SIZE
- 1;
415 b_res
[1].flags
|= IORESOURCE_IO
;
418 * Check whether prefetchable memory is supported
421 pci_read_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, &ctrl
);
422 if (!(ctrl
& PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
)) {
423 ctrl
|= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
;
424 pci_write_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, ctrl
);
425 pci_read_config_word(bridge
, PCI_CB_BRIDGE_CONTROL
, &ctrl
);
429 * If we have prefetchable memory support, allocate
430 * two regions. Otherwise, allocate one region of
433 if (ctrl
& PCI_CB_BRIDGE_CTL_PREFETCH_MEM0
) {
434 b_res
[2].start
= CARDBUS_MEM_SIZE
;
435 b_res
[2].end
= b_res
[2].start
+ CARDBUS_MEM_SIZE
- 1;
436 b_res
[2].flags
|= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
438 b_res
[3].start
= CARDBUS_MEM_SIZE
;
439 b_res
[3].end
= b_res
[3].start
+ CARDBUS_MEM_SIZE
- 1;
440 b_res
[3].flags
|= IORESOURCE_MEM
;
442 b_res
[3].start
= CARDBUS_MEM_SIZE
* 2;
443 b_res
[3].end
= b_res
[3].start
+ CARDBUS_MEM_SIZE
* 2 - 1;
444 b_res
[3].flags
|= IORESOURCE_MEM
;
449 pci_bus_size_bridges(struct pci_bus
*bus
)
452 unsigned long mask
, prefmask
;
454 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
455 struct pci_bus
*b
= dev
->subordinate
;
459 switch (dev
->class >> 8) {
460 case PCI_CLASS_BRIDGE_CARDBUS
:
461 pci_bus_size_cardbus(b
);
464 case PCI_CLASS_BRIDGE_PCI
:
466 pci_bus_size_bridges(b
);
475 switch (bus
->self
->class >> 8) {
476 case PCI_CLASS_BRIDGE_CARDBUS
:
477 /* don't size cardbuses yet. */
480 case PCI_CLASS_BRIDGE_PCI
:
481 pci_bridge_check_ranges(bus
);
484 /* If the bridge supports prefetchable range, size it
485 separately. If it doesn't, or its prefetchable window
486 has already been allocated by arch code, try
487 non-prefetchable range for both types of PCI memory
489 mask
= IORESOURCE_MEM
;
490 prefmask
= IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
491 if (pbus_size_mem(bus
, prefmask
, prefmask
))
492 mask
= prefmask
; /* Success, size non-prefetch only. */
493 pbus_size_mem(bus
, mask
, IORESOURCE_MEM
);
497 EXPORT_SYMBOL(pci_bus_size_bridges
);
500 pci_bus_assign_resources(struct pci_bus
*bus
)
505 pbus_assign_resources_sorted(bus
);
507 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
508 b
= dev
->subordinate
;
512 pci_bus_assign_resources(b
);
514 switch (dev
->class >> 8) {
515 case PCI_CLASS_BRIDGE_PCI
:
519 case PCI_CLASS_BRIDGE_CARDBUS
:
520 pci_setup_cardbus(b
);
524 printk(KERN_INFO
"PCI: not setting up bridge %s "
525 "for bus %d\n", pci_name(dev
), b
->number
);
530 EXPORT_SYMBOL(pci_bus_assign_resources
);
533 pci_assign_unassigned_resources(void)
537 /* Depth first, calculate sizes and alignments of all
538 subordinate buses. */
539 list_for_each_entry(bus
, &pci_root_buses
, node
) {
540 pci_bus_size_bridges(bus
);
542 /* Depth last, allocate resources and update the hardware. */
543 list_for_each_entry(bus
, &pci_root_buses
, node
) {
544 pci_bus_assign_resources(bus
);
545 pci_enable_bridges(bus
);