2 * Contains common pci routines for ALL ppc platform
3 * (based on pci_32.c and pci_64.c)
5 * Port for PPC64 David Engebretsen, IBM Corp.
6 * Contains common pci routines for ppc64 platform, pSeries and iSeries brands.
8 * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
9 * Rework, based on alpha PCI code.
11 * Common pmac/prep/chrp pci routines. -- Cort
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
19 #include <linux/kernel.h>
20 #include <linux/pci.h>
21 #include <linux/string.h>
22 #include <linux/init.h>
23 #include <linux/bootmem.h>
25 #include <linux/list.h>
26 #include <linux/syscalls.h>
27 #include <linux/irq.h>
28 #include <linux/vmalloc.h>
29 #include <linux/slab.h>
31 #include <linux/of_address.h>
33 #include <asm/processor.h>
35 #include <asm/pci-bridge.h>
36 #include <asm/byteorder.h>
38 static DEFINE_SPINLOCK(hose_spinlock);
41 /* XXX kill that some day ... */
42 static int global_phb_number; /* Global phb counter */
44 /* ISA Memory physical address */
45 resource_size_t isa_mem_base;
47 /* Default PCI flags is 0 on ppc32, modified at boot on ppc64 */
48 unsigned int pci_flags;
50 static struct dma_map_ops *pci_dma_ops = &dma_direct_ops;
52 void set_pci_dma_ops(struct dma_map_ops *dma_ops)
54 pci_dma_ops = dma_ops;
57 struct dma_map_ops *get_pci_dma_ops(void)
61 EXPORT_SYMBOL(get_pci_dma_ops);
63 struct pci_controller *pcibios_alloc_controller(struct device_node *dev)
65 struct pci_controller *phb;
67 phb = zalloc_maybe_bootmem(sizeof(struct pci_controller), GFP_KERNEL);
70 spin_lock(&hose_spinlock);
71 phb->global_number = global_phb_number++;
72 list_add_tail(&phb->list_node, &hose_list);
73 spin_unlock(&hose_spinlock);
75 phb->is_dynamic = mem_init_done;
79 void pcibios_free_controller(struct pci_controller *phb)
81 spin_lock(&hose_spinlock);
82 list_del(&phb->list_node);
83 spin_unlock(&hose_spinlock);
89 static resource_size_t pcibios_io_size(const struct pci_controller *hose)
91 return hose->io_resource.end - hose->io_resource.start + 1;
94 int pcibios_vaddr_is_ioport(void __iomem *address)
97 struct pci_controller *hose;
100 spin_lock(&hose_spinlock);
101 list_for_each_entry(hose, &hose_list, list_node) {
102 size = pcibios_io_size(hose);
103 if (address >= hose->io_base_virt &&
104 address < (hose->io_base_virt + size)) {
109 spin_unlock(&hose_spinlock);
113 unsigned long pci_address_to_pio(phys_addr_t address)
115 struct pci_controller *hose;
116 resource_size_t size;
117 unsigned long ret = ~0;
119 spin_lock(&hose_spinlock);
120 list_for_each_entry(hose, &hose_list, list_node) {
121 size = pcibios_io_size(hose);
122 if (address >= hose->io_base_phys &&
123 address < (hose->io_base_phys + size)) {
125 (unsigned long)hose->io_base_virt - _IO_BASE;
126 ret = base + (address - hose->io_base_phys);
130 spin_unlock(&hose_spinlock);
134 EXPORT_SYMBOL_GPL(pci_address_to_pio);
137 * Return the domain number for this bus.
139 int pci_domain_nr(struct pci_bus *bus)
141 struct pci_controller *hose = pci_bus_to_host(bus);
143 return hose->global_number;
145 EXPORT_SYMBOL(pci_domain_nr);
147 /* This routine is meant to be used early during boot, when the
148 * PCI bus numbers have not yet been assigned, and you need to
149 * issue PCI config cycles to an OF device.
150 * It could also be used to "fix" RTAS config cycles if you want
151 * to set pci_assign_all_buses to 1 and still use RTAS for PCI
154 struct pci_controller *pci_find_hose_for_OF_device(struct device_node *node)
157 struct pci_controller *hose, *tmp;
158 list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
159 if (hose->dn == node)
166 static ssize_t pci_show_devspec(struct device *dev,
167 struct device_attribute *attr, char *buf)
169 struct pci_dev *pdev;
170 struct device_node *np;
172 pdev = to_pci_dev(dev);
173 np = pci_device_to_OF_node(pdev);
174 if (np == NULL || np->full_name == NULL)
176 return sprintf(buf, "%s", np->full_name);
178 static DEVICE_ATTR(devspec, S_IRUGO, pci_show_devspec, NULL);
180 /* Add sysfs properties */
181 int pcibios_add_platform_entries(struct pci_dev *pdev)
183 return device_create_file(&pdev->dev, &dev_attr_devspec);
186 char __devinit *pcibios_setup(char *str)
192 * Reads the interrupt pin to determine if interrupt is use by card.
193 * If the interrupt is used, then gets the interrupt line from the
194 * openfirmware and sets it in the pci_dev and pci_config line.
196 int pci_read_irq_line(struct pci_dev *pci_dev)
201 /* The current device-tree that iSeries generates from the HV
202 * PCI informations doesn't contain proper interrupt routing,
203 * and all the fallback would do is print out crap, so we
204 * don't attempt to resolve the interrupts here at all, some
205 * iSeries specific fixup does it.
207 * In the long run, we will hopefully fix the generated device-tree
210 pr_debug("PCI: Try to map irq for %s...\n", pci_name(pci_dev));
213 memset(&oirq, 0xff, sizeof(oirq));
215 /* Try to get a mapping from the device-tree */
216 if (of_irq_map_pci(pci_dev, &oirq)) {
219 /* If that fails, lets fallback to what is in the config
220 * space and map that through the default controller. We
221 * also set the type to level low since that's what PCI
222 * interrupts are. If your platform does differently, then
223 * either provide a proper interrupt tree or don't use this
226 if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_PIN, &pin))
230 if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_LINE, &line) ||
231 line == 0xff || line == 0) {
234 pr_debug(" No map ! Using line %d (pin %d) from PCI config\n",
237 virq = irq_create_mapping(NULL, line);
239 set_irq_type(virq, IRQ_TYPE_LEVEL_LOW);
241 pr_debug(" Got one, spec %d cells (0x%08x 0x%08x...) on %s\n",
242 oirq.size, oirq.specifier[0], oirq.specifier[1],
243 oirq.controller ? oirq.controller->full_name :
246 virq = irq_create_of_mapping(oirq.controller, oirq.specifier,
249 if (virq == NO_IRQ) {
250 pr_debug(" Failed to map !\n");
254 pr_debug(" Mapped to linux irq %d\n", virq);
260 EXPORT_SYMBOL(pci_read_irq_line);
263 * Platform support for /proc/bus/pci/X/Y mmap()s,
264 * modelled on the sparc64 implementation by Dave Miller.
269 * Adjust vm_pgoff of VMA such that it is the physical page offset
270 * corresponding to the 32-bit pci bus offset for DEV requested by the user.
272 * Basically, the user finds the base address for his device which he wishes
273 * to mmap. They read the 32-bit value from the config space base register,
274 * add whatever PAGE_SIZE multiple offset they wish, and feed this into the
275 * offset parameter of mmap on /proc/bus/pci/XXX for that device.
277 * Returns negative error code on failure, zero on success.
279 static struct resource *__pci_mmap_make_offset(struct pci_dev *dev,
280 resource_size_t *offset,
281 enum pci_mmap_state mmap_state)
283 struct pci_controller *hose = pci_bus_to_host(dev->bus);
284 unsigned long io_offset = 0;
288 return NULL; /* should never happen */
290 /* If memory, add on the PCI bridge address offset */
291 if (mmap_state == pci_mmap_mem) {
292 #if 0 /* See comment in pci_resource_to_user() for why this is disabled */
293 *offset += hose->pci_mem_offset;
295 res_bit = IORESOURCE_MEM;
297 io_offset = (unsigned long)hose->io_base_virt - _IO_BASE;
298 *offset += io_offset;
299 res_bit = IORESOURCE_IO;
303 * Check that the offset requested corresponds to one of the
304 * resources of the device.
306 for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
307 struct resource *rp = &dev->resource[i];
308 int flags = rp->flags;
310 /* treat ROM as memory (should be already) */
311 if (i == PCI_ROM_RESOURCE)
312 flags |= IORESOURCE_MEM;
314 /* Active and same type? */
315 if ((flags & res_bit) == 0)
318 /* In the range of this resource? */
319 if (*offset < (rp->start & PAGE_MASK) || *offset > rp->end)
322 /* found it! construct the final physical address */
323 if (mmap_state == pci_mmap_io)
324 *offset += hose->io_base_phys - io_offset;
332 * Set vm_page_prot of VMA, as appropriate for this architecture, for a pci
335 static pgprot_t __pci_mmap_set_pgprot(struct pci_dev *dev, struct resource *rp,
337 enum pci_mmap_state mmap_state,
340 pgprot_t prot = protection;
342 /* Write combine is always 0 on non-memory space mappings. On
343 * memory space, if the user didn't pass 1, we check for a
344 * "prefetchable" resource. This is a bit hackish, but we use
345 * this to workaround the inability of /sysfs to provide a write
348 if (mmap_state != pci_mmap_mem)
350 else if (write_combine == 0) {
351 if (rp->flags & IORESOURCE_PREFETCH)
355 return pgprot_noncached(prot);
359 * This one is used by /dev/mem and fbdev who have no clue about the
360 * PCI device, it tries to find the PCI device first and calls the
363 pgprot_t pci_phys_mem_access_prot(struct file *file,
368 struct pci_dev *pdev = NULL;
369 struct resource *found = NULL;
370 resource_size_t offset = ((resource_size_t)pfn) << PAGE_SHIFT;
373 if (page_is_ram(pfn))
376 prot = pgprot_noncached(prot);
377 for_each_pci_dev(pdev) {
378 for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
379 struct resource *rp = &pdev->resource[i];
380 int flags = rp->flags;
382 /* Active and same type? */
383 if ((flags & IORESOURCE_MEM) == 0)
385 /* In the range of this resource? */
386 if (offset < (rp->start & PAGE_MASK) ||
396 if (found->flags & IORESOURCE_PREFETCH)
397 prot = pgprot_noncached_wc(prot);
401 pr_debug("PCI: Non-PCI map for %llx, prot: %lx\n",
402 (unsigned long long)offset, pgprot_val(prot));
408 * Perform the actual remap of the pages for a PCI device mapping, as
409 * appropriate for this architecture. The region in the process to map
410 * is described by vm_start and vm_end members of VMA, the base physical
411 * address is found in vm_pgoff.
412 * The pci device structure is provided so that architectures may make mapping
413 * decisions on a per-device or per-bus basis.
415 * Returns a negative error code on failure, zero on success.
417 int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
418 enum pci_mmap_state mmap_state, int write_combine)
420 resource_size_t offset =
421 ((resource_size_t)vma->vm_pgoff) << PAGE_SHIFT;
425 rp = __pci_mmap_make_offset(dev, &offset, mmap_state);
429 vma->vm_pgoff = offset >> PAGE_SHIFT;
430 vma->vm_page_prot = __pci_mmap_set_pgprot(dev, rp,
432 mmap_state, write_combine);
434 ret = remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
435 vma->vm_end - vma->vm_start, vma->vm_page_prot);
440 /* This provides legacy IO read access on a bus */
441 int pci_legacy_read(struct pci_bus *bus, loff_t port, u32 *val, size_t size)
443 unsigned long offset;
444 struct pci_controller *hose = pci_bus_to_host(bus);
445 struct resource *rp = &hose->io_resource;
448 /* Check if port can be supported by that bus. We only check
449 * the ranges of the PHB though, not the bus itself as the rules
450 * for forwarding legacy cycles down bridges are not our problem
451 * here. So if the host bridge supports it, we do it.
453 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
456 if (!(rp->flags & IORESOURCE_IO))
458 if (offset < rp->start || (offset + size) > rp->end)
460 addr = hose->io_base_virt + port;
464 *((u8 *)val) = in_8(addr);
469 *((u16 *)val) = in_le16(addr);
474 *((u32 *)val) = in_le32(addr);
480 /* This provides legacy IO write access on a bus */
481 int pci_legacy_write(struct pci_bus *bus, loff_t port, u32 val, size_t size)
483 unsigned long offset;
484 struct pci_controller *hose = pci_bus_to_host(bus);
485 struct resource *rp = &hose->io_resource;
488 /* Check if port can be supported by that bus. We only check
489 * the ranges of the PHB though, not the bus itself as the rules
490 * for forwarding legacy cycles down bridges are not our problem
491 * here. So if the host bridge supports it, we do it.
493 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
496 if (!(rp->flags & IORESOURCE_IO))
498 if (offset < rp->start || (offset + size) > rp->end)
500 addr = hose->io_base_virt + port;
502 /* WARNING: The generic code is idiotic. It gets passed a pointer
503 * to what can be a 1, 2 or 4 byte quantity and always reads that
504 * as a u32, which means that we have to correct the location of
505 * the data read within those 32 bits for size 1 and 2
509 out_8(addr, val >> 24);
514 out_le16(addr, val >> 16);
525 /* This provides legacy IO or memory mmap access on a bus */
526 int pci_mmap_legacy_page_range(struct pci_bus *bus,
527 struct vm_area_struct *vma,
528 enum pci_mmap_state mmap_state)
530 struct pci_controller *hose = pci_bus_to_host(bus);
531 resource_size_t offset =
532 ((resource_size_t)vma->vm_pgoff) << PAGE_SHIFT;
533 resource_size_t size = vma->vm_end - vma->vm_start;
536 pr_debug("pci_mmap_legacy_page_range(%04x:%02x, %s @%llx..%llx)\n",
537 pci_domain_nr(bus), bus->number,
538 mmap_state == pci_mmap_mem ? "MEM" : "IO",
539 (unsigned long long)offset,
540 (unsigned long long)(offset + size - 1));
542 if (mmap_state == pci_mmap_mem) {
545 * Because X is lame and can fail starting if it gets an error
546 * trying to mmap legacy_mem (instead of just moving on without
547 * legacy memory access) we fake it here by giving it anonymous
548 * memory, effectively behaving just like /dev/zero
550 if ((offset + size) > hose->isa_mem_size) {
553 "Process %s (pid:%d) mapped non-existing PCI"
554 "legacy memory for 0%04x:%02x\n",
555 current->comm, current->pid, pci_domain_nr(bus),
558 if (vma->vm_flags & VM_SHARED)
559 return shmem_zero_setup(vma);
562 offset += hose->isa_mem_phys;
564 unsigned long io_offset = (unsigned long)hose->io_base_virt - \
566 unsigned long roffset = offset + io_offset;
567 rp = &hose->io_resource;
568 if (!(rp->flags & IORESOURCE_IO))
570 if (roffset < rp->start || (roffset + size) > rp->end)
572 offset += hose->io_base_phys;
574 pr_debug(" -> mapping phys %llx\n", (unsigned long long)offset);
576 vma->vm_pgoff = offset >> PAGE_SHIFT;
577 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
578 return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
579 vma->vm_end - vma->vm_start,
583 void pci_resource_to_user(const struct pci_dev *dev, int bar,
584 const struct resource *rsrc,
585 resource_size_t *start, resource_size_t *end)
587 struct pci_controller *hose = pci_bus_to_host(dev->bus);
588 resource_size_t offset = 0;
593 if (rsrc->flags & IORESOURCE_IO)
594 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
596 /* We pass a fully fixed up address to userland for MMIO instead of
597 * a BAR value because X is lame and expects to be able to use that
598 * to pass to /dev/mem !
600 * That means that we'll have potentially 64 bits values where some
601 * userland apps only expect 32 (like X itself since it thinks only
602 * Sparc has 64 bits MMIO) but if we don't do that, we break it on
605 * Hopefully, the sysfs insterface is immune to that gunk. Once X
606 * has been fixed (and the fix spread enough), we can re-enable the
607 * 2 lines below and pass down a BAR value to userland. In that case
608 * we'll also have to re-enable the matching code in
609 * __pci_mmap_make_offset().
614 else if (rsrc->flags & IORESOURCE_MEM)
615 offset = hose->pci_mem_offset;
618 *start = rsrc->start - offset;
619 *end = rsrc->end - offset;
623 * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
624 * @hose: newly allocated pci_controller to be setup
625 * @dev: device node of the host bridge
626 * @primary: set if primary bus (32 bits only, soon to be deprecated)
628 * This function will parse the "ranges" property of a PCI host bridge device
629 * node and setup the resource mapping of a pci controller based on its
632 * Life would be boring if it wasn't for a few issues that we have to deal
635 * - We can only cope with one IO space range and up to 3 Memory space
636 * ranges. However, some machines (thanks Apple !) tend to split their
637 * space into lots of small contiguous ranges. So we have to coalesce.
639 * - We can only cope with all memory ranges having the same offset
640 * between CPU addresses and PCI addresses. Unfortunately, some bridges
641 * are setup for a large 1:1 mapping along with a small "window" which
642 * maps PCI address 0 to some arbitrary high address of the CPU space in
643 * order to give access to the ISA memory hole.
644 * The way out of here that I've chosen for now is to always set the
645 * offset based on the first resource found, then override it if we
646 * have a different offset and the previous was set by an ISA hole.
648 * - Some busses have IO space not starting at 0, which causes trouble with
649 * the way we do our IO resource renumbering. The code somewhat deals with
650 * it for 64 bits but I would expect problems on 32 bits.
652 * - Some 32 bits platforms such as 4xx can have physical space larger than
653 * 32 bits so we need to use 64 bits values for the parsing
655 void __devinit pci_process_bridge_OF_ranges(struct pci_controller *hose,
656 struct device_node *dev,
661 int pna = of_n_addr_cells(dev);
663 int memno = 0, isa_hole = -1;
665 unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
666 unsigned long long isa_mb = 0;
667 struct resource *res;
669 printk(KERN_INFO "PCI host bridge %s %s ranges:\n",
670 dev->full_name, primary ? "(primary)" : "");
672 /* Get ranges property */
673 ranges = of_get_property(dev, "ranges", &rlen);
678 pr_debug("Parsing ranges property...\n");
679 while ((rlen -= np * 4) >= 0) {
680 /* Read next ranges element */
681 pci_space = ranges[0];
682 pci_addr = of_read_number(ranges + 1, 2);
683 cpu_addr = of_translate_address(dev, ranges + 3);
684 size = of_read_number(ranges + pna + 3, 2);
686 pr_debug("pci_space: 0x%08x pci_addr:0x%016llx "
687 "cpu_addr:0x%016llx size:0x%016llx\n",
688 pci_space, pci_addr, cpu_addr, size);
692 /* If we failed translation or got a zero-sized region
693 * (some FW try to feed us with non sensical zero sized regions
694 * such as power3 which look like some kind of attempt
695 * at exposing the VGA memory hole)
697 if (cpu_addr == OF_BAD_ADDR || size == 0)
700 /* Now consume following elements while they are contiguous */
701 for (; rlen >= np * sizeof(u32);
702 ranges += np, rlen -= np * 4) {
703 if (ranges[0] != pci_space)
705 pci_next = of_read_number(ranges + 1, 2);
706 cpu_next = of_translate_address(dev, ranges + 3);
707 if (pci_next != pci_addr + size ||
708 cpu_next != cpu_addr + size)
710 size += of_read_number(ranges + pna + 3, 2);
713 /* Act based on address space type */
715 switch ((pci_space >> 24) & 0x3) {
716 case 1: /* PCI IO space */
718 " IO 0x%016llx..0x%016llx -> 0x%016llx\n",
719 cpu_addr, cpu_addr + size - 1, pci_addr);
721 /* We support only one IO range */
722 if (hose->pci_io_size) {
724 " \\--> Skipped (too many) !\n");
727 /* On 32 bits, limit I/O space to 16MB */
728 if (size > 0x01000000)
731 /* 32 bits needs to map IOs here */
732 hose->io_base_virt = ioremap(cpu_addr, size);
734 /* Expect trouble if pci_addr is not 0 */
737 (unsigned long)hose->io_base_virt;
738 /* pci_io_size and io_base_phys always represent IO
739 * space starting at 0 so we factor in pci_addr
741 hose->pci_io_size = pci_addr + size;
742 hose->io_base_phys = cpu_addr - pci_addr;
745 res = &hose->io_resource;
746 res->flags = IORESOURCE_IO;
747 res->start = pci_addr;
749 case 2: /* PCI Memory space */
750 case 3: /* PCI 64 bits Memory space */
752 " MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
753 cpu_addr, cpu_addr + size - 1, pci_addr,
754 (pci_space & 0x40000000) ? "Prefetch" : "");
756 /* We support only 3 memory ranges */
759 " \\--> Skipped (too many) !\n");
762 /* Handles ISA memory hole space here */
766 if (primary || isa_mem_base == 0)
767 isa_mem_base = cpu_addr;
768 hose->isa_mem_phys = cpu_addr;
769 hose->isa_mem_size = size;
772 /* We get the PCI/Mem offset from the first range or
773 * the, current one if the offset came from an ISA
774 * hole. If they don't match, bugger.
777 (isa_hole >= 0 && pci_addr != 0 &&
778 hose->pci_mem_offset == isa_mb))
779 hose->pci_mem_offset = cpu_addr - pci_addr;
780 else if (pci_addr != 0 &&
781 hose->pci_mem_offset != cpu_addr - pci_addr) {
783 " \\--> Skipped (offset mismatch) !\n");
788 res = &hose->mem_resources[memno++];
789 res->flags = IORESOURCE_MEM;
790 if (pci_space & 0x40000000)
791 res->flags |= IORESOURCE_PREFETCH;
792 res->start = cpu_addr;
796 res->name = dev->full_name;
797 res->end = res->start + size - 1;
804 /* If there's an ISA hole and the pci_mem_offset is -not- matching
805 * the ISA hole offset, then we need to remove the ISA hole from
806 * the resource list for that brige
808 if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
809 unsigned int next = isa_hole + 1;
810 printk(KERN_INFO " Removing ISA hole at 0x%016llx\n", isa_mb);
812 memmove(&hose->mem_resources[isa_hole],
813 &hose->mem_resources[next],
814 sizeof(struct resource) * (memno - next));
815 hose->mem_resources[--memno].flags = 0;
819 /* Decide whether to display the domain number in /proc */
820 int pci_proc_domain(struct pci_bus *bus)
822 struct pci_controller *hose = pci_bus_to_host(bus);
824 if (!(pci_flags & PCI_ENABLE_PROC_DOMAINS))
826 if (pci_flags & PCI_COMPAT_DOMAIN_0)
827 return hose->global_number != 0;
831 void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
832 struct resource *res)
834 resource_size_t offset = 0, mask = (resource_size_t)-1;
835 struct pci_controller *hose = pci_bus_to_host(dev->bus);
839 if (res->flags & IORESOURCE_IO) {
840 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
842 } else if (res->flags & IORESOURCE_MEM)
843 offset = hose->pci_mem_offset;
845 region->start = (res->start - offset) & mask;
846 region->end = (res->end - offset) & mask;
848 EXPORT_SYMBOL(pcibios_resource_to_bus);
850 void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
851 struct pci_bus_region *region)
853 resource_size_t offset = 0, mask = (resource_size_t)-1;
854 struct pci_controller *hose = pci_bus_to_host(dev->bus);
858 if (res->flags & IORESOURCE_IO) {
859 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
861 } else if (res->flags & IORESOURCE_MEM)
862 offset = hose->pci_mem_offset;
863 res->start = (region->start + offset) & mask;
864 res->end = (region->end + offset) & mask;
866 EXPORT_SYMBOL(pcibios_bus_to_resource);
868 /* Fixup a bus resource into a linux resource */
869 static void __devinit fixup_resource(struct resource *res, struct pci_dev *dev)
871 struct pci_controller *hose = pci_bus_to_host(dev->bus);
872 resource_size_t offset = 0, mask = (resource_size_t)-1;
874 if (res->flags & IORESOURCE_IO) {
875 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
877 } else if (res->flags & IORESOURCE_MEM)
878 offset = hose->pci_mem_offset;
880 res->start = (res->start + offset) & mask;
881 res->end = (res->end + offset) & mask;
884 /* This header fixup will do the resource fixup for all devices as they are
885 * probed, but not for bridge ranges
887 static void __devinit pcibios_fixup_resources(struct pci_dev *dev)
889 struct pci_controller *hose = pci_bus_to_host(dev->bus);
893 printk(KERN_ERR "No host bridge for PCI dev %s !\n",
897 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
898 struct resource *res = dev->resource + i;
901 /* On platforms that have PCI_PROBE_ONLY set, we don't
902 * consider 0 as an unassigned BAR value. It's technically
903 * a valid value, but linux doesn't like it... so when we can
904 * re-assign things, we do so, but if we can't, we keep it
905 * around and hope for the best...
907 if (res->start == 0 && !(pci_flags & PCI_PROBE_ONLY)) {
908 pr_debug("PCI:%s Resource %d %016llx-%016llx [%x]" \
911 (unsigned long long)res->start,
912 (unsigned long long)res->end,
913 (unsigned int)res->flags);
914 res->end -= res->start;
916 res->flags |= IORESOURCE_UNSET;
920 pr_debug("PCI:%s Resource %d %016llx-%016llx [%x] fixup...\n",
922 (unsigned long long)res->start,\
923 (unsigned long long)res->end,
924 (unsigned int)res->flags);
926 fixup_resource(res, dev);
928 pr_debug("PCI:%s %016llx-%016llx\n",
930 (unsigned long long)res->start,
931 (unsigned long long)res->end);
934 DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pcibios_fixup_resources);
936 /* This function tries to figure out if a bridge resource has been initialized
937 * by the firmware or not. It doesn't have to be absolutely bullet proof, but
938 * things go more smoothly when it gets it right. It should covers cases such
939 * as Apple "closed" bridge resources and bare-metal pSeries unassigned bridges
941 static int __devinit pcibios_uninitialized_bridge_resource(struct pci_bus *bus,
942 struct resource *res)
944 struct pci_controller *hose = pci_bus_to_host(bus);
945 struct pci_dev *dev = bus->self;
946 resource_size_t offset;
950 /* We don't do anything if PCI_PROBE_ONLY is set */
951 if (pci_flags & PCI_PROBE_ONLY)
954 /* Job is a bit different between memory and IO */
955 if (res->flags & IORESOURCE_MEM) {
956 /* If the BAR is non-0 (res != pci_mem_offset) then it's
957 * probably been initialized by somebody
959 if (res->start != hose->pci_mem_offset)
962 /* The BAR is 0, let's check if memory decoding is enabled on
963 * the bridge. If not, we consider it unassigned
965 pci_read_config_word(dev, PCI_COMMAND, &command);
966 if ((command & PCI_COMMAND_MEMORY) == 0)
969 /* Memory decoding is enabled and the BAR is 0. If any of
970 * the bridge resources covers that starting address (0 then
971 * it's good enough for us for memory
973 for (i = 0; i < 3; i++) {
974 if ((hose->mem_resources[i].flags & IORESOURCE_MEM) &&
975 hose->mem_resources[i].start == hose->pci_mem_offset)
979 /* Well, it starts at 0 and we know it will collide so we may as
980 * well consider it as unassigned. That covers the Apple case.
984 /* If the BAR is non-0, then we consider it assigned */
985 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
986 if (((res->start - offset) & 0xfffffffful) != 0)
989 /* Here, we are a bit different than memory as typically IO
990 * space starting at low addresses -is- valid. What we do
991 * instead if that we consider as unassigned anything that
992 * doesn't have IO enabled in the PCI command register,
995 pci_read_config_word(dev, PCI_COMMAND, &command);
996 if (command & PCI_COMMAND_IO)
999 /* It's starting at 0 and IO is disabled in the bridge, consider
1006 /* Fixup resources of a PCI<->PCI bridge */
1007 static void __devinit pcibios_fixup_bridge(struct pci_bus *bus)
1009 struct resource *res;
1012 struct pci_dev *dev = bus->self;
1014 pci_bus_for_each_resource(bus, res, i) {
1015 res = bus->resource[i];
1020 if (i >= 3 && bus->self->transparent)
1023 pr_debug("PCI:%s Bus rsrc %d %016llx-%016llx [%x] fixup...\n",
1025 (unsigned long long)res->start,\
1026 (unsigned long long)res->end,
1027 (unsigned int)res->flags);
1030 fixup_resource(res, dev);
1032 /* Try to detect uninitialized P2P bridge resources,
1033 * and clear them out so they get re-assigned later
1035 if (pcibios_uninitialized_bridge_resource(bus, res)) {
1037 pr_debug("PCI:%s (unassigned)\n",
1040 pr_debug("PCI:%s %016llx-%016llx\n",
1042 (unsigned long long)res->start,
1043 (unsigned long long)res->end);
1048 void __devinit pcibios_setup_bus_self(struct pci_bus *bus)
1050 /* Fix up the bus resources for P2P bridges */
1051 if (bus->self != NULL)
1052 pcibios_fixup_bridge(bus);
1055 void __devinit pcibios_setup_bus_devices(struct pci_bus *bus)
1057 struct pci_dev *dev;
1059 pr_debug("PCI: Fixup bus devices %d (%s)\n",
1060 bus->number, bus->self ? pci_name(bus->self) : "PHB");
1062 list_for_each_entry(dev, &bus->devices, bus_list) {
1063 /* Setup OF node pointer in archdata */
1064 dev->dev.of_node = pci_device_to_OF_node(dev);
1066 /* Fixup NUMA node as it may not be setup yet by the generic
1067 * code and is needed by the DMA init
1069 set_dev_node(&dev->dev, pcibus_to_node(dev->bus));
1071 /* Hook up default DMA ops */
1072 set_dma_ops(&dev->dev, pci_dma_ops);
1073 dev->dev.archdata.dma_data = (void *)PCI_DRAM_OFFSET;
1075 /* Read default IRQs and fixup if necessary */
1076 pci_read_irq_line(dev);
1080 void __devinit pcibios_fixup_bus(struct pci_bus *bus)
1082 /* When called from the generic PCI probe, read PCI<->PCI bridge
1083 * bases. This is -not- called when generating the PCI tree from
1084 * the OF device-tree.
1086 if (bus->self != NULL)
1087 pci_read_bridge_bases(bus);
1089 /* Now fixup the bus bus */
1090 pcibios_setup_bus_self(bus);
1092 /* Now fixup devices on that bus */
1093 pcibios_setup_bus_devices(bus);
1095 EXPORT_SYMBOL(pcibios_fixup_bus);
1097 static int skip_isa_ioresource_align(struct pci_dev *dev)
1099 if ((pci_flags & PCI_CAN_SKIP_ISA_ALIGN) &&
1100 !(dev->bus->bridge_ctl & PCI_BRIDGE_CTL_ISA))
1106 * We need to avoid collisions with `mirrored' VGA ports
1107 * and other strange ISA hardware, so we always want the
1108 * addresses to be allocated in the 0x000-0x0ff region
1111 * Why? Because some silly external IO cards only decode
1112 * the low 10 bits of the IO address. The 0x00-0xff region
1113 * is reserved for motherboard devices that decode all 16
1114 * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
1115 * but we want to try to avoid allocating at 0x2900-0x2bff
1116 * which might have be mirrored at 0x0100-0x03ff..
1118 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
1119 resource_size_t size, resource_size_t align)
1121 struct pci_dev *dev = data;
1122 resource_size_t start = res->start;
1124 if (res->flags & IORESOURCE_IO) {
1125 if (skip_isa_ioresource_align(dev))
1128 start = (start + 0x3ff) & ~0x3ff;
1133 EXPORT_SYMBOL(pcibios_align_resource);
1136 * Reparent resource children of pr that conflict with res
1137 * under res, and make res replace those children.
1139 static int __init reparent_resources(struct resource *parent,
1140 struct resource *res)
1142 struct resource *p, **pp;
1143 struct resource **firstpp = NULL;
1145 for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
1146 if (p->end < res->start)
1148 if (res->end < p->start)
1150 if (p->start < res->start || p->end > res->end)
1151 return -1; /* not completely contained */
1152 if (firstpp == NULL)
1155 if (firstpp == NULL)
1156 return -1; /* didn't find any conflicting entries? */
1157 res->parent = parent;
1158 res->child = *firstpp;
1162 for (p = res->child; p != NULL; p = p->sibling) {
1164 pr_debug("PCI: Reparented %s [%llx..%llx] under %s\n",
1166 (unsigned long long)p->start,
1167 (unsigned long long)p->end, res->name);
1173 * Handle resources of PCI devices. If the world were perfect, we could
1174 * just allocate all the resource regions and do nothing more. It isn't.
1175 * On the other hand, we cannot just re-allocate all devices, as it would
1176 * require us to know lots of host bridge internals. So we attempt to
1177 * keep as much of the original configuration as possible, but tweak it
1178 * when it's found to be wrong.
1180 * Known BIOS problems we have to work around:
1181 * - I/O or memory regions not configured
1182 * - regions configured, but not enabled in the command register
1183 * - bogus I/O addresses above 64K used
1184 * - expansion ROMs left enabled (this may sound harmless, but given
1185 * the fact the PCI specs explicitly allow address decoders to be
1186 * shared between expansion ROMs and other resource regions, it's
1187 * at least dangerous)
1190 * (1) Allocate resources for all buses behind PCI-to-PCI bridges.
1191 * This gives us fixed barriers on where we can allocate.
1192 * (2) Allocate resources for all enabled devices. If there is
1193 * a collision, just mark the resource as unallocated. Also
1194 * disable expansion ROMs during this step.
1195 * (3) Try to allocate resources for disabled devices. If the
1196 * resources were assigned correctly, everything goes well,
1197 * if they weren't, they won't disturb allocation of other
1199 * (4) Assign new addresses to resources which were either
1200 * not configured at all or misconfigured. If explicitly
1201 * requested by the user, configure expansion ROM address
1205 void pcibios_allocate_bus_resources(struct pci_bus *bus)
1209 struct resource *res, *pr;
1211 pr_debug("PCI: Allocating bus resources for %04x:%02x...\n",
1212 pci_domain_nr(bus), bus->number);
1214 pci_bus_for_each_resource(bus, res, i) {
1215 res = bus->resource[i];
1216 if (!res || !res->flags
1217 || res->start > res->end || res->parent)
1219 if (bus->parent == NULL)
1220 pr = (res->flags & IORESOURCE_IO) ?
1221 &ioport_resource : &iomem_resource;
1223 /* Don't bother with non-root busses when
1224 * re-assigning all resources. We clear the
1225 * resource flags as if they were colliding
1226 * and as such ensure proper re-allocation
1229 if (pci_flags & PCI_REASSIGN_ALL_RSRC)
1230 goto clear_resource;
1231 pr = pci_find_parent_resource(bus->self, res);
1233 /* this happens when the generic PCI
1234 * code (wrongly) decides that this
1235 * bridge is transparent -- paulus
1241 pr_debug("PCI: %s (bus %d) bridge rsrc %d: %016llx-%016llx "
1242 "[0x%x], parent %p (%s)\n",
1243 bus->self ? pci_name(bus->self) : "PHB",
1245 (unsigned long long)res->start,
1246 (unsigned long long)res->end,
1247 (unsigned int)res->flags,
1248 pr, (pr && pr->name) ? pr->name : "nil");
1250 if (pr && !(pr->flags & IORESOURCE_UNSET)) {
1251 if (request_resource(pr, res) == 0)
1254 * Must be a conflict with an existing entry.
1255 * Move that entry (or entries) under the
1256 * bridge resource and try again.
1258 if (reparent_resources(pr, res) == 0)
1261 printk(KERN_WARNING "PCI: Cannot allocate resource region "
1262 "%d of PCI bridge %d, will remap\n", i, bus->number);
1264 res->start = res->end = 0;
1268 list_for_each_entry(b, &bus->children, node)
1269 pcibios_allocate_bus_resources(b);
1272 static inline void __devinit alloc_resource(struct pci_dev *dev, int idx)
1274 struct resource *pr, *r = &dev->resource[idx];
1276 pr_debug("PCI: Allocating %s: Resource %d: %016llx..%016llx [%x]\n",
1278 (unsigned long long)r->start,
1279 (unsigned long long)r->end,
1280 (unsigned int)r->flags);
1282 pr = pci_find_parent_resource(dev, r);
1283 if (!pr || (pr->flags & IORESOURCE_UNSET) ||
1284 request_resource(pr, r) < 0) {
1285 printk(KERN_WARNING "PCI: Cannot allocate resource region %d"
1286 " of device %s, will remap\n", idx, pci_name(dev));
1288 pr_debug("PCI: parent is %p: %016llx-%016llx [%x]\n",
1290 (unsigned long long)pr->start,
1291 (unsigned long long)pr->end,
1292 (unsigned int)pr->flags);
1293 /* We'll assign a new address later */
1294 r->flags |= IORESOURCE_UNSET;
1300 static void __init pcibios_allocate_resources(int pass)
1302 struct pci_dev *dev = NULL;
1307 for_each_pci_dev(dev) {
1308 pci_read_config_word(dev, PCI_COMMAND, &command);
1309 for (idx = 0; idx <= PCI_ROM_RESOURCE; idx++) {
1310 r = &dev->resource[idx];
1311 if (r->parent) /* Already allocated */
1313 if (!r->flags || (r->flags & IORESOURCE_UNSET))
1314 continue; /* Not assigned at all */
1315 /* We only allocate ROMs on pass 1 just in case they
1316 * have been screwed up by firmware
1318 if (idx == PCI_ROM_RESOURCE)
1320 if (r->flags & IORESOURCE_IO)
1321 disabled = !(command & PCI_COMMAND_IO);
1323 disabled = !(command & PCI_COMMAND_MEMORY);
1324 if (pass == disabled)
1325 alloc_resource(dev, idx);
1329 r = &dev->resource[PCI_ROM_RESOURCE];
1331 /* Turn the ROM off, leave the resource region,
1332 * but keep it unregistered.
1335 pci_read_config_dword(dev, dev->rom_base_reg, ®);
1336 if (reg & PCI_ROM_ADDRESS_ENABLE) {
1337 pr_debug("PCI: Switching off ROM of %s\n",
1339 r->flags &= ~IORESOURCE_ROM_ENABLE;
1340 pci_write_config_dword(dev, dev->rom_base_reg,
1341 reg & ~PCI_ROM_ADDRESS_ENABLE);
1347 static void __init pcibios_reserve_legacy_regions(struct pci_bus *bus)
1349 struct pci_controller *hose = pci_bus_to_host(bus);
1350 resource_size_t offset;
1351 struct resource *res, *pres;
1354 pr_debug("Reserving legacy ranges for domain %04x\n",
1355 pci_domain_nr(bus));
1358 if (!(hose->io_resource.flags & IORESOURCE_IO))
1360 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
1361 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
1362 BUG_ON(res == NULL);
1363 res->name = "Legacy IO";
1364 res->flags = IORESOURCE_IO;
1365 res->start = offset;
1366 res->end = (offset + 0xfff) & 0xfffffffful;
1367 pr_debug("Candidate legacy IO: %pR\n", res);
1368 if (request_resource(&hose->io_resource, res)) {
1370 "PCI %04x:%02x Cannot reserve Legacy IO %pR\n",
1371 pci_domain_nr(bus), bus->number, res);
1376 /* Check for memory */
1377 offset = hose->pci_mem_offset;
1378 pr_debug("hose mem offset: %016llx\n", (unsigned long long)offset);
1379 for (i = 0; i < 3; i++) {
1380 pres = &hose->mem_resources[i];
1381 if (!(pres->flags & IORESOURCE_MEM))
1383 pr_debug("hose mem res: %pR\n", pres);
1384 if ((pres->start - offset) <= 0xa0000 &&
1385 (pres->end - offset) >= 0xbffff)
1390 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
1391 BUG_ON(res == NULL);
1392 res->name = "Legacy VGA memory";
1393 res->flags = IORESOURCE_MEM;
1394 res->start = 0xa0000 + offset;
1395 res->end = 0xbffff + offset;
1396 pr_debug("Candidate VGA memory: %pR\n", res);
1397 if (request_resource(pres, res)) {
1399 "PCI %04x:%02x Cannot reserve VGA memory %pR\n",
1400 pci_domain_nr(bus), bus->number, res);
1405 void __init pcibios_resource_survey(void)
1409 /* Allocate and assign resources. If we re-assign everything, then
1410 * we skip the allocate phase
1412 list_for_each_entry(b, &pci_root_buses, node)
1413 pcibios_allocate_bus_resources(b);
1415 if (!(pci_flags & PCI_REASSIGN_ALL_RSRC)) {
1416 pcibios_allocate_resources(0);
1417 pcibios_allocate_resources(1);
1420 /* Before we start assigning unassigned resource, we try to reserve
1421 * the low IO area and the VGA memory area if they intersect the
1422 * bus available resources to avoid allocating things on top of them
1424 if (!(pci_flags & PCI_PROBE_ONLY)) {
1425 list_for_each_entry(b, &pci_root_buses, node)
1426 pcibios_reserve_legacy_regions(b);
1429 /* Now, if the platform didn't decide to blindly trust the firmware,
1430 * we proceed to assigning things that were left unassigned
1432 if (!(pci_flags & PCI_PROBE_ONLY)) {
1433 pr_debug("PCI: Assigning unassigned resources...\n");
1434 pci_assign_unassigned_resources();
1438 #ifdef CONFIG_HOTPLUG
1440 /* This is used by the PCI hotplug driver to allocate resource
1441 * of newly plugged busses. We can try to consolidate with the
1442 * rest of the code later, for now, keep it as-is as our main
1443 * resource allocation function doesn't deal with sub-trees yet.
1445 void __devinit pcibios_claim_one_bus(struct pci_bus *bus)
1447 struct pci_dev *dev;
1448 struct pci_bus *child_bus;
1450 list_for_each_entry(dev, &bus->devices, bus_list) {
1453 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
1454 struct resource *r = &dev->resource[i];
1456 if (r->parent || !r->start || !r->flags)
1459 pr_debug("PCI: Claiming %s: "
1460 "Resource %d: %016llx..%016llx [%x]\n",
1462 (unsigned long long)r->start,
1463 (unsigned long long)r->end,
1464 (unsigned int)r->flags);
1466 pci_claim_resource(dev, i);
1470 list_for_each_entry(child_bus, &bus->children, node)
1471 pcibios_claim_one_bus(child_bus);
1473 EXPORT_SYMBOL_GPL(pcibios_claim_one_bus);
1476 /* pcibios_finish_adding_to_bus
1478 * This is to be called by the hotplug code after devices have been
1479 * added to a bus, this include calling it for a PHB that is just
1482 void pcibios_finish_adding_to_bus(struct pci_bus *bus)
1484 pr_debug("PCI: Finishing adding to hotplug bus %04x:%02x\n",
1485 pci_domain_nr(bus), bus->number);
1487 /* Allocate bus and devices resources */
1488 pcibios_allocate_bus_resources(bus);
1489 pcibios_claim_one_bus(bus);
1491 /* Add new devices to global lists. Register in proc, sysfs. */
1492 pci_bus_add_devices(bus);
1495 /* eeh_add_device_tree_late(bus); */
1497 EXPORT_SYMBOL_GPL(pcibios_finish_adding_to_bus);
1499 #endif /* CONFIG_HOTPLUG */
1501 int pcibios_enable_device(struct pci_dev *dev, int mask)
1503 return pci_enable_resources(dev, mask);
1506 void __devinit pcibios_setup_phb_resources(struct pci_controller *hose)
1508 struct pci_bus *bus = hose->bus;
1509 struct resource *res;
1512 /* Hookup PHB IO resource */
1513 bus->resource[0] = res = &hose->io_resource;
1516 printk(KERN_WARNING "PCI: I/O resource not set for host"
1517 " bridge %s (domain %d)\n",
1518 hose->dn->full_name, hose->global_number);
1519 /* Workaround for lack of IO resource only on 32-bit */
1520 res->start = (unsigned long)hose->io_base_virt - isa_io_base;
1521 res->end = res->start + IO_SPACE_LIMIT;
1522 res->flags = IORESOURCE_IO;
1525 pr_debug("PCI: PHB IO resource = %016llx-%016llx [%lx]\n",
1526 (unsigned long long)res->start,
1527 (unsigned long long)res->end,
1528 (unsigned long)res->flags);
1530 /* Hookup PHB Memory resources */
1531 for (i = 0; i < 3; ++i) {
1532 res = &hose->mem_resources[i];
1536 printk(KERN_ERR "PCI: Memory resource 0 not set for "
1537 "host bridge %s (domain %d)\n",
1538 hose->dn->full_name, hose->global_number);
1540 /* Workaround for lack of MEM resource only on 32-bit */
1541 res->start = hose->pci_mem_offset;
1542 res->end = (resource_size_t)-1LL;
1543 res->flags = IORESOURCE_MEM;
1546 bus->resource[i+1] = res;
1548 pr_debug("PCI: PHB MEM resource %d = %016llx-%016llx [%lx]\n",
1549 i, (unsigned long long)res->start,
1550 (unsigned long long)res->end,
1551 (unsigned long)res->flags);
1554 pr_debug("PCI: PHB MEM offset = %016llx\n",
1555 (unsigned long long)hose->pci_mem_offset);
1556 pr_debug("PCI: PHB IO offset = %08lx\n",
1557 (unsigned long)hose->io_base_virt - _IO_BASE);
1561 * Null PCI config access functions, for the case when we can't
1564 #define NULL_PCI_OP(rw, size, type) \
1566 null_##rw##_config_##size(struct pci_dev *dev, int offset, type val) \
1568 return PCIBIOS_DEVICE_NOT_FOUND; \
1572 null_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
1575 return PCIBIOS_DEVICE_NOT_FOUND;
1579 null_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
1582 return PCIBIOS_DEVICE_NOT_FOUND;
1585 static struct pci_ops null_pci_ops = {
1586 .read = null_read_config,
1587 .write = null_write_config,
1591 * These functions are used early on before PCI scanning is done
1592 * and all of the pci_dev and pci_bus structures have been created.
1594 static struct pci_bus *
1595 fake_pci_bus(struct pci_controller *hose, int busnr)
1597 static struct pci_bus bus;
1600 printk(KERN_ERR "Can't find hose for PCI bus %d!\n", busnr);
1604 bus.ops = hose ? hose->ops : &null_pci_ops;
1608 #define EARLY_PCI_OP(rw, size, type) \
1609 int early_##rw##_config_##size(struct pci_controller *hose, int bus, \
1610 int devfn, int offset, type value) \
1612 return pci_bus_##rw##_config_##size(fake_pci_bus(hose, bus), \
1613 devfn, offset, value); \
1616 EARLY_PCI_OP(read, byte, u8 *)
1617 EARLY_PCI_OP(read, word, u16 *)
1618 EARLY_PCI_OP(read, dword, u32 *)
1619 EARLY_PCI_OP(write, byte, u8)
1620 EARLY_PCI_OP(write, word, u16)
1621 EARLY_PCI_OP(write, dword, u32)
1623 int early_find_capability(struct pci_controller *hose, int bus, int devfn,
1626 return pci_bus_find_capability(fake_pci_bus(hose, bus), devfn, cap);