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 && !r->parent)
308 /* Sizing the IO windows of the PCI-PCI bridge is trivial,
309 since these windows have 4K granularity and the IO ranges
310 of non-bridge PCI devices are limited to 256 bytes.
311 We must be careful with the ISA aliasing though. */
312 static void pbus_size_io(struct pci_bus *bus)
315 struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
316 unsigned long size = 0, size1 = 0;
321 list_for_each_entry(dev, &bus->devices, bus_list) {
324 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
325 struct resource *r = &dev->resource[i];
326 unsigned long r_size;
328 if (r->parent || !(r->flags & IORESOURCE_IO))
330 r_size = resource_size(r);
333 /* Might be re-aligned for ISA */
339 /* To be fixed in 2.5: we should have sort of HAVE_ISA
340 flag in the struct pci_bus. */
341 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
342 size = (size & 0xff) + ((size & ~0xffUL) << 2);
344 size = ALIGN(size + size1, 4096);
349 /* Alignment of the IO window is always 4K */
351 b_res->end = b_res->start + size - 1;
352 b_res->flags |= IORESOURCE_STARTALIGN;
355 /* Calculate the size of the bus and minimal alignment which
356 guarantees that all child resources fit in this size. */
357 static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type)
360 resource_size_t min_align, align, size;
361 resource_size_t aligns[12]; /* Alignments from 1Mb to 2Gb */
362 int order, max_order;
363 struct resource *b_res = find_free_bus_resource(bus, type);
364 unsigned int mem64_mask = 0;
369 memset(aligns, 0, sizeof(aligns));
373 mem64_mask = b_res->flags & IORESOURCE_MEM_64;
374 b_res->flags &= ~IORESOURCE_MEM_64;
376 list_for_each_entry(dev, &bus->devices, bus_list) {
379 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
380 struct resource *r = &dev->resource[i];
381 resource_size_t r_size;
383 if (r->parent || (r->flags & mask) != type)
385 r_size = resource_size(r);
386 /* For bridges size != alignment */
387 align = resource_alignment(r);
388 order = __ffs(align) - 20;
390 dev_warn(&dev->dev, "BAR %d bad alignment %llx: "
391 "%pR\n", i, (unsigned long long)align, r);
398 /* Exclude ranges with size > align from
399 calculation of the alignment. */
401 aligns[order] += align;
402 if (order > max_order)
404 mem64_mask &= r->flags & IORESOURCE_MEM_64;
410 for (order = 0; order <= max_order; order++) {
411 resource_size_t align1 = 1;
413 align1 <<= (order + 20);
417 else if (ALIGN(align + min_align, min_align) < align1)
418 min_align = align1 >> 1;
419 align += aligns[order];
421 size = ALIGN(size, min_align);
426 b_res->start = min_align;
427 b_res->end = size + min_align - 1;
428 b_res->flags |= IORESOURCE_STARTALIGN;
429 b_res->flags |= mem64_mask;
433 static void pci_bus_size_cardbus(struct pci_bus *bus)
435 struct pci_dev *bridge = bus->self;
436 struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
440 * Reserve some resources for CardBus. We reserve
441 * a fixed amount of bus space for CardBus bridges.
444 b_res[0].end = pci_cardbus_io_size - 1;
445 b_res[0].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
448 b_res[1].end = pci_cardbus_io_size - 1;
449 b_res[1].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
452 * Check whether prefetchable memory is supported
455 pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
456 if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) {
457 ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0;
458 pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
459 pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
463 * If we have prefetchable memory support, allocate
464 * two regions. Otherwise, allocate one region of
467 if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
469 b_res[2].end = pci_cardbus_mem_size - 1;
470 b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_SIZEALIGN;
473 b_res[3].end = pci_cardbus_mem_size - 1;
474 b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
477 b_res[3].end = pci_cardbus_mem_size * 2 - 1;
478 b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
482 void __ref pci_bus_size_bridges(struct pci_bus *bus)
485 unsigned long mask, prefmask;
487 list_for_each_entry(dev, &bus->devices, bus_list) {
488 struct pci_bus *b = dev->subordinate;
492 switch (dev->class >> 8) {
493 case PCI_CLASS_BRIDGE_CARDBUS:
494 pci_bus_size_cardbus(b);
497 case PCI_CLASS_BRIDGE_PCI:
499 pci_bus_size_bridges(b);
508 switch (bus->self->class >> 8) {
509 case PCI_CLASS_BRIDGE_CARDBUS:
510 /* don't size cardbuses yet. */
513 case PCI_CLASS_BRIDGE_PCI:
514 pci_bridge_check_ranges(bus);
517 /* If the bridge supports prefetchable range, size it
518 separately. If it doesn't, or its prefetchable window
519 has already been allocated by arch code, try
520 non-prefetchable range for both types of PCI memory
522 mask = IORESOURCE_MEM;
523 prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
524 if (pbus_size_mem(bus, prefmask, prefmask))
525 mask = prefmask; /* Success, size non-prefetch only. */
526 pbus_size_mem(bus, mask, IORESOURCE_MEM);
530 EXPORT_SYMBOL(pci_bus_size_bridges);
532 void __ref pci_bus_assign_resources(const struct pci_bus *bus)
537 pbus_assign_resources_sorted(bus);
539 list_for_each_entry(dev, &bus->devices, bus_list) {
540 b = dev->subordinate;
544 pci_bus_assign_resources(b);
546 switch (dev->class >> 8) {
547 case PCI_CLASS_BRIDGE_PCI:
551 case PCI_CLASS_BRIDGE_CARDBUS:
552 pci_setup_cardbus(b);
556 dev_info(&dev->dev, "not setting up bridge for bus "
557 "%04x:%02x\n", pci_domain_nr(b), b->number);
562 EXPORT_SYMBOL(pci_bus_assign_resources);
564 static void pci_bus_dump_res(struct pci_bus *bus)
568 for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
569 struct resource *res = bus->resource[i];
570 if (!res || !res->end)
573 dev_printk(KERN_DEBUG, &bus->dev, "resource %d %s %pR\n", i,
574 (res->flags & IORESOURCE_IO) ? "io: " :
575 ((res->flags & IORESOURCE_PREFETCH)? "pref mem":"mem:"),
580 static void pci_bus_dump_resources(struct pci_bus *bus)
586 pci_bus_dump_res(bus);
588 list_for_each_entry(dev, &bus->devices, bus_list) {
589 b = dev->subordinate;
593 pci_bus_dump_resources(b);
598 pci_assign_unassigned_resources(void)
602 /* Depth first, calculate sizes and alignments of all
603 subordinate buses. */
604 list_for_each_entry(bus, &pci_root_buses, node) {
605 pci_bus_size_bridges(bus);
607 /* Depth last, allocate resources and update the hardware. */
608 list_for_each_entry(bus, &pci_root_buses, node) {
609 pci_bus_assign_resources(bus);
610 pci_enable_bridges(bus);
613 /* dump the resource on buses */
614 list_for_each_entry(bus, &pci_root_buses, node) {
615 pci_bus_dump_resources(bus);