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)) {
61 /* FIXME: get rid of this */
72 void pci_setup_cardbus(struct pci_bus *bus)
74 struct pci_dev *bridge = bus->self;
75 struct pci_bus_region region;
77 dev_info(&bridge->dev, "CardBus bridge, secondary bus %04x:%02x\n",
78 pci_domain_nr(bus), bus->number);
80 pcibios_resource_to_bus(bridge, ®ion, bus->resource[0]);
81 if (bus->resource[0]->flags & IORESOURCE_IO) {
83 * The IO resource is allocated a range twice as large as it
84 * would normally need. This allows us to set both IO regs.
86 dev_info(&bridge->dev, " IO window: %#08lx-%#08lx\n",
87 (unsigned long)region.start,
88 (unsigned long)region.end);
89 pci_write_config_dword(bridge, PCI_CB_IO_BASE_0,
91 pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0,
95 pcibios_resource_to_bus(bridge, ®ion, bus->resource[1]);
96 if (bus->resource[1]->flags & IORESOURCE_IO) {
97 dev_info(&bridge->dev, " IO window: %#08lx-%#08lx\n",
98 (unsigned long)region.start,
99 (unsigned long)region.end);
100 pci_write_config_dword(bridge, PCI_CB_IO_BASE_1,
102 pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1,
106 pcibios_resource_to_bus(bridge, ®ion, bus->resource[2]);
107 if (bus->resource[2]->flags & IORESOURCE_MEM) {
108 dev_info(&bridge->dev, " PREFETCH window: %#08lx-%#08lx\n",
109 (unsigned long)region.start,
110 (unsigned long)region.end);
111 pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0,
113 pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0,
117 pcibios_resource_to_bus(bridge, ®ion, bus->resource[3]);
118 if (bus->resource[3]->flags & IORESOURCE_MEM) {
119 dev_info(&bridge->dev, " MEM window: %#08lx-%#08lx\n",
120 (unsigned long)region.start,
121 (unsigned long)region.end);
122 pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_1,
124 pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_1,
128 EXPORT_SYMBOL(pci_setup_cardbus);
130 /* Initialize bridges with base/limit values we have collected.
131 PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
132 requires that if there is no I/O ports or memory behind the
133 bridge, corresponding range must be turned off by writing base
134 value greater than limit to the bridge's base/limit registers.
136 Note: care must be taken when updating I/O base/limit registers
137 of bridges which support 32-bit I/O. This update requires two
138 config space writes, so it's quite possible that an I/O window of
139 the bridge will have some undesirable address (e.g. 0) after the
140 first write. Ditto 64-bit prefetchable MMIO. */
141 static void pci_setup_bridge(struct pci_bus *bus)
143 struct pci_dev *bridge = bus->self;
144 struct pci_bus_region region;
145 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. */
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 bu = upper_32_bits(region.start);
207 lu = upper_32_bits(region.end);
208 dev_info(&bridge->dev, " PREFETCH window: %#016llx-%#016llx\n",
209 (unsigned long long)region.start,
210 (unsigned long long)region.end);
214 dev_info(&bridge->dev, " PREFETCH window: disabled\n");
216 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);
218 /* Set the upper 32 bits of PREF base & limit. */
219 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu);
220 pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu);
222 pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl);
225 /* Check whether the bridge supports optional I/O and
226 prefetchable memory ranges. If not, the respective
227 base/limit registers must be read-only and read as 0. */
228 static void pci_bridge_check_ranges(struct pci_bus *bus)
232 struct pci_dev *bridge = bus->self;
233 struct resource *b_res;
235 b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
236 b_res[1].flags |= IORESOURCE_MEM;
238 pci_read_config_word(bridge, PCI_IO_BASE, &io);
240 pci_write_config_word(bridge, PCI_IO_BASE, 0xf0f0);
241 pci_read_config_word(bridge, PCI_IO_BASE, &io);
242 pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
245 b_res[0].flags |= IORESOURCE_IO;
246 /* DECchip 21050 pass 2 errata: the bridge may miss an address
247 disconnect boundary by one PCI data phase.
248 Workaround: do not use prefetching on this device. */
249 if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
251 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
253 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
255 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
256 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
259 b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
262 /* Helper function for sizing routines: find first available
263 bus resource of a given type. Note: we intentionally skip
264 the bus resources which have already been assigned (that is,
265 have non-NULL parent resource). */
266 static struct resource *find_free_bus_resource(struct pci_bus *bus, unsigned long type)
270 unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
273 for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
274 r = bus->resource[i];
275 if (r == &ioport_resource || r == &iomem_resource)
277 if (r && (r->flags & type_mask) == type && !r->parent)
283 /* Sizing the IO windows of the PCI-PCI bridge is trivial,
284 since these windows have 4K granularity and the IO ranges
285 of non-bridge PCI devices are limited to 256 bytes.
286 We must be careful with the ISA aliasing though. */
287 static void pbus_size_io(struct pci_bus *bus)
290 struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
291 unsigned long size = 0, size1 = 0;
296 list_for_each_entry(dev, &bus->devices, bus_list) {
299 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
300 struct resource *r = &dev->resource[i];
301 unsigned long r_size;
303 if (r->parent || !(r->flags & IORESOURCE_IO))
305 r_size = resource_size(r);
308 /* Might be re-aligned for ISA */
314 /* To be fixed in 2.5: we should have sort of HAVE_ISA
315 flag in the struct pci_bus. */
316 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
317 size = (size & 0xff) + ((size & ~0xffUL) << 2);
319 size = ALIGN(size + size1, 4096);
324 /* Alignment of the IO window is always 4K */
326 b_res->end = b_res->start + size - 1;
327 b_res->flags |= IORESOURCE_STARTALIGN;
330 /* Calculate the size of the bus and minimal alignment which
331 guarantees that all child resources fit in this size. */
332 static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type)
335 resource_size_t min_align, align, size;
336 resource_size_t aligns[12]; /* Alignments from 1Mb to 2Gb */
337 int order, max_order;
338 struct resource *b_res = find_free_bus_resource(bus, type);
343 memset(aligns, 0, sizeof(aligns));
347 list_for_each_entry(dev, &bus->devices, bus_list) {
350 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
351 struct resource *r = &dev->resource[i];
352 resource_size_t r_size;
354 if (r->parent || (r->flags & mask) != type)
356 r_size = resource_size(r);
357 /* For bridges size != alignment */
358 align = resource_alignment(r);
359 order = __ffs(align) - 20;
361 dev_warn(&dev->dev, "BAR %d bad alignment %llx: "
362 "%pR\n", i, (unsigned long long)align, r);
369 /* Exclude ranges with size > align from
370 calculation of the alignment. */
372 aligns[order] += align;
373 if (order > max_order)
380 for (order = 0; order <= max_order; order++) {
381 resource_size_t align1 = 1;
383 align1 <<= (order + 20);
387 else if (ALIGN(align + min_align, min_align) < align1)
388 min_align = align1 >> 1;
389 align += aligns[order];
391 size = ALIGN(size, min_align);
396 b_res->start = min_align;
397 b_res->end = size + min_align - 1;
398 b_res->flags |= IORESOURCE_STARTALIGN;
402 static void pci_bus_size_cardbus(struct pci_bus *bus)
404 struct pci_dev *bridge = bus->self;
405 struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
409 * Reserve some resources for CardBus. We reserve
410 * a fixed amount of bus space for CardBus bridges.
413 b_res[0].end = pci_cardbus_io_size - 1;
414 b_res[0].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
417 b_res[1].end = pci_cardbus_io_size - 1;
418 b_res[1].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
421 * Check whether prefetchable memory is supported
424 pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
425 if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) {
426 ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0;
427 pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
428 pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
432 * If we have prefetchable memory support, allocate
433 * two regions. Otherwise, allocate one region of
436 if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
438 b_res[2].end = pci_cardbus_mem_size - 1;
439 b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_SIZEALIGN;
442 b_res[3].end = pci_cardbus_mem_size - 1;
443 b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
446 b_res[3].end = pci_cardbus_mem_size * 2 - 1;
447 b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
451 void __ref pci_bus_size_bridges(struct pci_bus *bus)
454 unsigned long mask, prefmask;
456 list_for_each_entry(dev, &bus->devices, bus_list) {
457 struct pci_bus *b = dev->subordinate;
461 switch (dev->class >> 8) {
462 case PCI_CLASS_BRIDGE_CARDBUS:
463 pci_bus_size_cardbus(b);
466 case PCI_CLASS_BRIDGE_PCI:
468 pci_bus_size_bridges(b);
477 switch (bus->self->class >> 8) {
478 case PCI_CLASS_BRIDGE_CARDBUS:
479 /* don't size cardbuses yet. */
482 case PCI_CLASS_BRIDGE_PCI:
483 pci_bridge_check_ranges(bus);
486 /* If the bridge supports prefetchable range, size it
487 separately. If it doesn't, or its prefetchable window
488 has already been allocated by arch code, try
489 non-prefetchable range for both types of PCI memory
491 mask = IORESOURCE_MEM;
492 prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
493 if (pbus_size_mem(bus, prefmask, prefmask))
494 mask = prefmask; /* Success, size non-prefetch only. */
495 pbus_size_mem(bus, mask, IORESOURCE_MEM);
499 EXPORT_SYMBOL(pci_bus_size_bridges);
501 void __ref pci_bus_assign_resources(const struct pci_bus *bus)
506 pbus_assign_resources_sorted(bus);
508 list_for_each_entry(dev, &bus->devices, bus_list) {
509 b = dev->subordinate;
513 pci_bus_assign_resources(b);
515 switch (dev->class >> 8) {
516 case PCI_CLASS_BRIDGE_PCI:
520 case PCI_CLASS_BRIDGE_CARDBUS:
521 pci_setup_cardbus(b);
525 dev_info(&dev->dev, "not setting up bridge for bus "
526 "%04x:%02x\n", pci_domain_nr(b), b->number);
531 EXPORT_SYMBOL(pci_bus_assign_resources);
533 static void pci_bus_dump_res(struct pci_bus *bus)
537 for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
538 struct resource *res = bus->resource[i];
539 if (!res || !res->end)
542 dev_printk(KERN_DEBUG, &bus->dev, "resource %d %s %pR\n", i,
543 (res->flags & IORESOURCE_IO) ? "io: " :
544 ((res->flags & IORESOURCE_PREFETCH)? "pref mem":"mem:"),
549 static void pci_bus_dump_resources(struct pci_bus *bus)
555 pci_bus_dump_res(bus);
557 list_for_each_entry(dev, &bus->devices, bus_list) {
558 b = dev->subordinate;
562 pci_bus_dump_resources(b);
567 pci_assign_unassigned_resources(void)
571 /* Depth first, calculate sizes and alignments of all
572 subordinate buses. */
573 list_for_each_entry(bus, &pci_root_buses, node) {
574 pci_bus_size_bridges(bus);
576 /* Depth last, allocate resources and update the hardware. */
577 list_for_each_entry(bus, &pci_root_buses, node) {
578 pci_bus_assign_resources(bus);
579 pci_enable_bridges(bus);
582 /* dump the resource on buses */
583 list_for_each_entry(bus, &pci_root_buses, node) {
584 pci_bus_dump_resources(bus);