s390/bpf: Fix skb_copy_bits() parameter passing
[linux/fpc-iii.git] / arch / microblaze / pci / pci-common.c
blobb30e41c0c0335cf2ab79e716c9c41c0ebced18e8
1 /*
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>
24 #include <linux/mm.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>
30 #include <linux/of.h>
31 #include <linux/of_address.h>
32 #include <linux/of_irq.h>
33 #include <linux/of_pci.h>
34 #include <linux/export.h>
36 #include <asm/processor.h>
37 #include <linux/io.h>
38 #include <asm/pci-bridge.h>
39 #include <asm/byteorder.h>
41 static DEFINE_SPINLOCK(hose_spinlock);
42 LIST_HEAD(hose_list);
44 /* XXX kill that some day ... */
45 static int global_phb_number; /* Global phb counter */
47 /* ISA Memory physical address */
48 resource_size_t isa_mem_base;
50 unsigned long isa_io_base;
51 static int pci_bus_count;
53 struct pci_controller *pcibios_alloc_controller(struct device_node *dev)
55 struct pci_controller *phb;
57 phb = zalloc_maybe_bootmem(sizeof(struct pci_controller), GFP_KERNEL);
58 if (!phb)
59 return NULL;
60 spin_lock(&hose_spinlock);
61 phb->global_number = global_phb_number++;
62 list_add_tail(&phb->list_node, &hose_list);
63 spin_unlock(&hose_spinlock);
64 phb->dn = dev;
65 phb->is_dynamic = mem_init_done;
66 return phb;
69 void pcibios_free_controller(struct pci_controller *phb)
71 spin_lock(&hose_spinlock);
72 list_del(&phb->list_node);
73 spin_unlock(&hose_spinlock);
75 if (phb->is_dynamic)
76 kfree(phb);
79 static resource_size_t pcibios_io_size(const struct pci_controller *hose)
81 return resource_size(&hose->io_resource);
84 int pcibios_vaddr_is_ioport(void __iomem *address)
86 int ret = 0;
87 struct pci_controller *hose;
88 resource_size_t size;
90 spin_lock(&hose_spinlock);
91 list_for_each_entry(hose, &hose_list, list_node) {
92 size = pcibios_io_size(hose);
93 if (address >= hose->io_base_virt &&
94 address < (hose->io_base_virt + size)) {
95 ret = 1;
96 break;
99 spin_unlock(&hose_spinlock);
100 return ret;
103 unsigned long pci_address_to_pio(phys_addr_t address)
105 struct pci_controller *hose;
106 resource_size_t size;
107 unsigned long ret = ~0;
109 spin_lock(&hose_spinlock);
110 list_for_each_entry(hose, &hose_list, list_node) {
111 size = pcibios_io_size(hose);
112 if (address >= hose->io_base_phys &&
113 address < (hose->io_base_phys + size)) {
114 unsigned long base =
115 (unsigned long)hose->io_base_virt - _IO_BASE;
116 ret = base + (address - hose->io_base_phys);
117 break;
120 spin_unlock(&hose_spinlock);
122 return ret;
124 EXPORT_SYMBOL_GPL(pci_address_to_pio);
127 * Return the domain number for this bus.
129 int pci_domain_nr(struct pci_bus *bus)
131 struct pci_controller *hose = pci_bus_to_host(bus);
133 return hose->global_number;
135 EXPORT_SYMBOL(pci_domain_nr);
137 /* This routine is meant to be used early during boot, when the
138 * PCI bus numbers have not yet been assigned, and you need to
139 * issue PCI config cycles to an OF device.
140 * It could also be used to "fix" RTAS config cycles if you want
141 * to set pci_assign_all_buses to 1 and still use RTAS for PCI
142 * config cycles.
144 struct pci_controller *pci_find_hose_for_OF_device(struct device_node *node)
146 while (node) {
147 struct pci_controller *hose, *tmp;
148 list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
149 if (hose->dn == node)
150 return hose;
151 node = node->parent;
153 return NULL;
156 void pcibios_set_master(struct pci_dev *dev)
158 /* No special bus mastering setup handling */
162 * Platform support for /proc/bus/pci/X/Y mmap()s,
163 * modelled on the sparc64 implementation by Dave Miller.
164 * -- paulus.
168 * Adjust vm_pgoff of VMA such that it is the physical page offset
169 * corresponding to the 32-bit pci bus offset for DEV requested by the user.
171 * Basically, the user finds the base address for his device which he wishes
172 * to mmap. They read the 32-bit value from the config space base register,
173 * add whatever PAGE_SIZE multiple offset they wish, and feed this into the
174 * offset parameter of mmap on /proc/bus/pci/XXX for that device.
176 * Returns negative error code on failure, zero on success.
178 static struct resource *__pci_mmap_make_offset(struct pci_dev *dev,
179 resource_size_t *offset,
180 enum pci_mmap_state mmap_state)
182 struct pci_controller *hose = pci_bus_to_host(dev->bus);
183 unsigned long io_offset = 0;
184 int i, res_bit;
186 if (!hose)
187 return NULL; /* should never happen */
189 /* If memory, add on the PCI bridge address offset */
190 if (mmap_state == pci_mmap_mem) {
191 #if 0 /* See comment in pci_resource_to_user() for why this is disabled */
192 *offset += hose->pci_mem_offset;
193 #endif
194 res_bit = IORESOURCE_MEM;
195 } else {
196 io_offset = (unsigned long)hose->io_base_virt - _IO_BASE;
197 *offset += io_offset;
198 res_bit = IORESOURCE_IO;
202 * Check that the offset requested corresponds to one of the
203 * resources of the device.
205 for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
206 struct resource *rp = &dev->resource[i];
207 int flags = rp->flags;
209 /* treat ROM as memory (should be already) */
210 if (i == PCI_ROM_RESOURCE)
211 flags |= IORESOURCE_MEM;
213 /* Active and same type? */
214 if ((flags & res_bit) == 0)
215 continue;
217 /* In the range of this resource? */
218 if (*offset < (rp->start & PAGE_MASK) || *offset > rp->end)
219 continue;
221 /* found it! construct the final physical address */
222 if (mmap_state == pci_mmap_io)
223 *offset += hose->io_base_phys - io_offset;
224 return rp;
227 return NULL;
231 * Set vm_page_prot of VMA, as appropriate for this architecture, for a pci
232 * device mapping.
234 static pgprot_t __pci_mmap_set_pgprot(struct pci_dev *dev, struct resource *rp,
235 pgprot_t protection,
236 enum pci_mmap_state mmap_state,
237 int write_combine)
239 pgprot_t prot = protection;
241 /* Write combine is always 0 on non-memory space mappings. On
242 * memory space, if the user didn't pass 1, we check for a
243 * "prefetchable" resource. This is a bit hackish, but we use
244 * this to workaround the inability of /sysfs to provide a write
245 * combine bit
247 if (mmap_state != pci_mmap_mem)
248 write_combine = 0;
249 else if (write_combine == 0) {
250 if (rp->flags & IORESOURCE_PREFETCH)
251 write_combine = 1;
254 return pgprot_noncached(prot);
258 * This one is used by /dev/mem and fbdev who have no clue about the
259 * PCI device, it tries to find the PCI device first and calls the
260 * above routine
262 pgprot_t pci_phys_mem_access_prot(struct file *file,
263 unsigned long pfn,
264 unsigned long size,
265 pgprot_t prot)
267 struct pci_dev *pdev = NULL;
268 struct resource *found = NULL;
269 resource_size_t offset = ((resource_size_t)pfn) << PAGE_SHIFT;
270 int i;
272 if (page_is_ram(pfn))
273 return prot;
275 prot = pgprot_noncached(prot);
276 for_each_pci_dev(pdev) {
277 for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
278 struct resource *rp = &pdev->resource[i];
279 int flags = rp->flags;
281 /* Active and same type? */
282 if ((flags & IORESOURCE_MEM) == 0)
283 continue;
284 /* In the range of this resource? */
285 if (offset < (rp->start & PAGE_MASK) ||
286 offset > rp->end)
287 continue;
288 found = rp;
289 break;
291 if (found)
292 break;
294 if (found) {
295 if (found->flags & IORESOURCE_PREFETCH)
296 prot = pgprot_noncached_wc(prot);
297 pci_dev_put(pdev);
300 pr_debug("PCI: Non-PCI map for %llx, prot: %lx\n",
301 (unsigned long long)offset, pgprot_val(prot));
303 return prot;
307 * Perform the actual remap of the pages for a PCI device mapping, as
308 * appropriate for this architecture. The region in the process to map
309 * is described by vm_start and vm_end members of VMA, the base physical
310 * address is found in vm_pgoff.
311 * The pci device structure is provided so that architectures may make mapping
312 * decisions on a per-device or per-bus basis.
314 * Returns a negative error code on failure, zero on success.
316 int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
317 enum pci_mmap_state mmap_state, int write_combine)
319 resource_size_t offset =
320 ((resource_size_t)vma->vm_pgoff) << PAGE_SHIFT;
321 struct resource *rp;
322 int ret;
324 rp = __pci_mmap_make_offset(dev, &offset, mmap_state);
325 if (rp == NULL)
326 return -EINVAL;
328 vma->vm_pgoff = offset >> PAGE_SHIFT;
329 vma->vm_page_prot = __pci_mmap_set_pgprot(dev, rp,
330 vma->vm_page_prot,
331 mmap_state, write_combine);
333 ret = remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
334 vma->vm_end - vma->vm_start, vma->vm_page_prot);
336 return ret;
339 /* This provides legacy IO read access on a bus */
340 int pci_legacy_read(struct pci_bus *bus, loff_t port, u32 *val, size_t size)
342 unsigned long offset;
343 struct pci_controller *hose = pci_bus_to_host(bus);
344 struct resource *rp = &hose->io_resource;
345 void __iomem *addr;
347 /* Check if port can be supported by that bus. We only check
348 * the ranges of the PHB though, not the bus itself as the rules
349 * for forwarding legacy cycles down bridges are not our problem
350 * here. So if the host bridge supports it, we do it.
352 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
353 offset += port;
355 if (!(rp->flags & IORESOURCE_IO))
356 return -ENXIO;
357 if (offset < rp->start || (offset + size) > rp->end)
358 return -ENXIO;
359 addr = hose->io_base_virt + port;
361 switch (size) {
362 case 1:
363 *((u8 *)val) = in_8(addr);
364 return 1;
365 case 2:
366 if (port & 1)
367 return -EINVAL;
368 *((u16 *)val) = in_le16(addr);
369 return 2;
370 case 4:
371 if (port & 3)
372 return -EINVAL;
373 *((u32 *)val) = in_le32(addr);
374 return 4;
376 return -EINVAL;
379 /* This provides legacy IO write access on a bus */
380 int pci_legacy_write(struct pci_bus *bus, loff_t port, u32 val, size_t size)
382 unsigned long offset;
383 struct pci_controller *hose = pci_bus_to_host(bus);
384 struct resource *rp = &hose->io_resource;
385 void __iomem *addr;
387 /* Check if port can be supported by that bus. We only check
388 * the ranges of the PHB though, not the bus itself as the rules
389 * for forwarding legacy cycles down bridges are not our problem
390 * here. So if the host bridge supports it, we do it.
392 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
393 offset += port;
395 if (!(rp->flags & IORESOURCE_IO))
396 return -ENXIO;
397 if (offset < rp->start || (offset + size) > rp->end)
398 return -ENXIO;
399 addr = hose->io_base_virt + port;
401 /* WARNING: The generic code is idiotic. It gets passed a pointer
402 * to what can be a 1, 2 or 4 byte quantity and always reads that
403 * as a u32, which means that we have to correct the location of
404 * the data read within those 32 bits for size 1 and 2
406 switch (size) {
407 case 1:
408 out_8(addr, val >> 24);
409 return 1;
410 case 2:
411 if (port & 1)
412 return -EINVAL;
413 out_le16(addr, val >> 16);
414 return 2;
415 case 4:
416 if (port & 3)
417 return -EINVAL;
418 out_le32(addr, val);
419 return 4;
421 return -EINVAL;
424 /* This provides legacy IO or memory mmap access on a bus */
425 int pci_mmap_legacy_page_range(struct pci_bus *bus,
426 struct vm_area_struct *vma,
427 enum pci_mmap_state mmap_state)
429 struct pci_controller *hose = pci_bus_to_host(bus);
430 resource_size_t offset =
431 ((resource_size_t)vma->vm_pgoff) << PAGE_SHIFT;
432 resource_size_t size = vma->vm_end - vma->vm_start;
433 struct resource *rp;
435 pr_debug("pci_mmap_legacy_page_range(%04x:%02x, %s @%llx..%llx)\n",
436 pci_domain_nr(bus), bus->number,
437 mmap_state == pci_mmap_mem ? "MEM" : "IO",
438 (unsigned long long)offset,
439 (unsigned long long)(offset + size - 1));
441 if (mmap_state == pci_mmap_mem) {
442 /* Hack alert !
444 * Because X is lame and can fail starting if it gets an error
445 * trying to mmap legacy_mem (instead of just moving on without
446 * legacy memory access) we fake it here by giving it anonymous
447 * memory, effectively behaving just like /dev/zero
449 if ((offset + size) > hose->isa_mem_size) {
450 #ifdef CONFIG_MMU
451 pr_debug("Process %s (pid:%d) mapped non-existing PCI",
452 current->comm, current->pid);
453 pr_debug("legacy memory for 0%04x:%02x\n",
454 pci_domain_nr(bus), bus->number);
455 #endif
456 if (vma->vm_flags & VM_SHARED)
457 return shmem_zero_setup(vma);
458 return 0;
460 offset += hose->isa_mem_phys;
461 } else {
462 unsigned long io_offset = (unsigned long)hose->io_base_virt -
463 _IO_BASE;
464 unsigned long roffset = offset + io_offset;
465 rp = &hose->io_resource;
466 if (!(rp->flags & IORESOURCE_IO))
467 return -ENXIO;
468 if (roffset < rp->start || (roffset + size) > rp->end)
469 return -ENXIO;
470 offset += hose->io_base_phys;
472 pr_debug(" -> mapping phys %llx\n", (unsigned long long)offset);
474 vma->vm_pgoff = offset >> PAGE_SHIFT;
475 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
476 return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
477 vma->vm_end - vma->vm_start,
478 vma->vm_page_prot);
481 void pci_resource_to_user(const struct pci_dev *dev, int bar,
482 const struct resource *rsrc,
483 resource_size_t *start, resource_size_t *end)
485 struct pci_controller *hose = pci_bus_to_host(dev->bus);
486 resource_size_t offset = 0;
488 if (hose == NULL)
489 return;
491 if (rsrc->flags & IORESOURCE_IO)
492 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
494 /* We pass a fully fixed up address to userland for MMIO instead of
495 * a BAR value because X is lame and expects to be able to use that
496 * to pass to /dev/mem !
498 * That means that we'll have potentially 64 bits values where some
499 * userland apps only expect 32 (like X itself since it thinks only
500 * Sparc has 64 bits MMIO) but if we don't do that, we break it on
501 * 32 bits CHRPs :-(
503 * Hopefully, the sysfs insterface is immune to that gunk. Once X
504 * has been fixed (and the fix spread enough), we can re-enable the
505 * 2 lines below and pass down a BAR value to userland. In that case
506 * we'll also have to re-enable the matching code in
507 * __pci_mmap_make_offset().
509 * BenH.
511 #if 0
512 else if (rsrc->flags & IORESOURCE_MEM)
513 offset = hose->pci_mem_offset;
514 #endif
516 *start = rsrc->start - offset;
517 *end = rsrc->end - offset;
521 * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
522 * @hose: newly allocated pci_controller to be setup
523 * @dev: device node of the host bridge
524 * @primary: set if primary bus (32 bits only, soon to be deprecated)
526 * This function will parse the "ranges" property of a PCI host bridge device
527 * node and setup the resource mapping of a pci controller based on its
528 * content.
530 * Life would be boring if it wasn't for a few issues that we have to deal
531 * with here:
533 * - We can only cope with one IO space range and up to 3 Memory space
534 * ranges. However, some machines (thanks Apple !) tend to split their
535 * space into lots of small contiguous ranges. So we have to coalesce.
537 * - We can only cope with all memory ranges having the same offset
538 * between CPU addresses and PCI addresses. Unfortunately, some bridges
539 * are setup for a large 1:1 mapping along with a small "window" which
540 * maps PCI address 0 to some arbitrary high address of the CPU space in
541 * order to give access to the ISA memory hole.
542 * The way out of here that I've chosen for now is to always set the
543 * offset based on the first resource found, then override it if we
544 * have a different offset and the previous was set by an ISA hole.
546 * - Some busses have IO space not starting at 0, which causes trouble with
547 * the way we do our IO resource renumbering. The code somewhat deals with
548 * it for 64 bits but I would expect problems on 32 bits.
550 * - Some 32 bits platforms such as 4xx can have physical space larger than
551 * 32 bits so we need to use 64 bits values for the parsing
553 void pci_process_bridge_OF_ranges(struct pci_controller *hose,
554 struct device_node *dev, int primary)
556 int memno = 0, isa_hole = -1;
557 unsigned long long isa_mb = 0;
558 struct resource *res;
559 struct of_pci_range range;
560 struct of_pci_range_parser parser;
562 pr_info("PCI host bridge %s %s ranges:\n",
563 dev->full_name, primary ? "(primary)" : "");
565 /* Check for ranges property */
566 if (of_pci_range_parser_init(&parser, dev))
567 return;
569 pr_debug("Parsing ranges property...\n");
570 for_each_of_pci_range(&parser, &range) {
571 /* Read next ranges element */
572 pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ",
573 range.pci_space, range.pci_addr);
574 pr_debug("cpu_addr:0x%016llx size:0x%016llx\n",
575 range.cpu_addr, range.size);
577 /* If we failed translation or got a zero-sized region
578 * (some FW try to feed us with non sensical zero sized regions
579 * such as power3 which look like some kind of attempt
580 * at exposing the VGA memory hole)
582 if (range.cpu_addr == OF_BAD_ADDR || range.size == 0)
583 continue;
585 /* Act based on address space type */
586 res = NULL;
587 switch (range.flags & IORESOURCE_TYPE_BITS) {
588 case IORESOURCE_IO:
589 pr_info(" IO 0x%016llx..0x%016llx -> 0x%016llx\n",
590 range.cpu_addr, range.cpu_addr + range.size - 1,
591 range.pci_addr);
593 /* We support only one IO range */
594 if (hose->pci_io_size) {
595 pr_info(" \\--> Skipped (too many) !\n");
596 continue;
598 /* On 32 bits, limit I/O space to 16MB */
599 if (range.size > 0x01000000)
600 range.size = 0x01000000;
602 /* 32 bits needs to map IOs here */
603 hose->io_base_virt = ioremap(range.cpu_addr,
604 range.size);
606 /* Expect trouble if pci_addr is not 0 */
607 if (primary)
608 isa_io_base =
609 (unsigned long)hose->io_base_virt;
610 /* pci_io_size and io_base_phys always represent IO
611 * space starting at 0 so we factor in pci_addr
613 hose->pci_io_size = range.pci_addr + range.size;
614 hose->io_base_phys = range.cpu_addr - range.pci_addr;
616 /* Build resource */
617 res = &hose->io_resource;
618 range.cpu_addr = range.pci_addr;
620 break;
621 case IORESOURCE_MEM:
622 pr_info(" MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
623 range.cpu_addr, range.cpu_addr + range.size - 1,
624 range.pci_addr,
625 (range.pci_space & 0x40000000) ?
626 "Prefetch" : "");
628 /* We support only 3 memory ranges */
629 if (memno >= 3) {
630 pr_info(" \\--> Skipped (too many) !\n");
631 continue;
633 /* Handles ISA memory hole space here */
634 if (range.pci_addr == 0) {
635 isa_mb = range.cpu_addr;
636 isa_hole = memno;
637 if (primary || isa_mem_base == 0)
638 isa_mem_base = range.cpu_addr;
639 hose->isa_mem_phys = range.cpu_addr;
640 hose->isa_mem_size = range.size;
643 /* We get the PCI/Mem offset from the first range or
644 * the, current one if the offset came from an ISA
645 * hole. If they don't match, bugger.
647 if (memno == 0 ||
648 (isa_hole >= 0 && range.pci_addr != 0 &&
649 hose->pci_mem_offset == isa_mb))
650 hose->pci_mem_offset = range.cpu_addr -
651 range.pci_addr;
652 else if (range.pci_addr != 0 &&
653 hose->pci_mem_offset != range.cpu_addr -
654 range.pci_addr) {
655 pr_info(" \\--> Skipped (offset mismatch) !\n");
656 continue;
659 /* Build resource */
660 res = &hose->mem_resources[memno++];
661 break;
663 if (res != NULL) {
664 res->name = dev->full_name;
665 res->flags = range.flags;
666 res->start = range.cpu_addr;
667 res->end = range.cpu_addr + range.size - 1;
668 res->parent = res->child = res->sibling = NULL;
672 /* If there's an ISA hole and the pci_mem_offset is -not- matching
673 * the ISA hole offset, then we need to remove the ISA hole from
674 * the resource list for that brige
676 if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
677 unsigned int next = isa_hole + 1;
678 pr_info(" Removing ISA hole at 0x%016llx\n", isa_mb);
679 if (next < memno)
680 memmove(&hose->mem_resources[isa_hole],
681 &hose->mem_resources[next],
682 sizeof(struct resource) * (memno - next));
683 hose->mem_resources[--memno].flags = 0;
687 /* Decide whether to display the domain number in /proc */
688 int pci_proc_domain(struct pci_bus *bus)
690 return 0;
693 /* This header fixup will do the resource fixup for all devices as they are
694 * probed, but not for bridge ranges
696 static void pcibios_fixup_resources(struct pci_dev *dev)
698 struct pci_controller *hose = pci_bus_to_host(dev->bus);
699 int i;
701 if (!hose) {
702 pr_err("No host bridge for PCI dev %s !\n",
703 pci_name(dev));
704 return;
706 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
707 struct resource *res = dev->resource + i;
708 if (!res->flags)
709 continue;
710 if (res->start == 0) {
711 pr_debug("PCI:%s Resource %d %016llx-%016llx [%x]",
712 pci_name(dev), i,
713 (unsigned long long)res->start,
714 (unsigned long long)res->end,
715 (unsigned int)res->flags);
716 pr_debug("is unassigned\n");
717 res->end -= res->start;
718 res->start = 0;
719 res->flags |= IORESOURCE_UNSET;
720 continue;
723 pr_debug("PCI:%s Resource %d %016llx-%016llx [%x]\n",
724 pci_name(dev), i,
725 (unsigned long long)res->start,
726 (unsigned long long)res->end,
727 (unsigned int)res->flags);
730 DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pcibios_fixup_resources);
732 /* This function tries to figure out if a bridge resource has been initialized
733 * by the firmware or not. It doesn't have to be absolutely bullet proof, but
734 * things go more smoothly when it gets it right. It should covers cases such
735 * as Apple "closed" bridge resources and bare-metal pSeries unassigned bridges
737 static int pcibios_uninitialized_bridge_resource(struct pci_bus *bus,
738 struct resource *res)
740 struct pci_controller *hose = pci_bus_to_host(bus);
741 struct pci_dev *dev = bus->self;
742 resource_size_t offset;
743 u16 command;
744 int i;
746 /* Job is a bit different between memory and IO */
747 if (res->flags & IORESOURCE_MEM) {
748 /* If the BAR is non-0 (res != pci_mem_offset) then it's
749 * probably been initialized by somebody
751 if (res->start != hose->pci_mem_offset)
752 return 0;
754 /* The BAR is 0, let's check if memory decoding is enabled on
755 * the bridge. If not, we consider it unassigned
757 pci_read_config_word(dev, PCI_COMMAND, &command);
758 if ((command & PCI_COMMAND_MEMORY) == 0)
759 return 1;
761 /* Memory decoding is enabled and the BAR is 0. If any of
762 * the bridge resources covers that starting address (0 then
763 * it's good enough for us for memory
765 for (i = 0; i < 3; i++) {
766 if ((hose->mem_resources[i].flags & IORESOURCE_MEM) &&
767 hose->mem_resources[i].start == hose->pci_mem_offset)
768 return 0;
771 /* Well, it starts at 0 and we know it will collide so we may as
772 * well consider it as unassigned. That covers the Apple case.
774 return 1;
775 } else {
776 /* If the BAR is non-0, then we consider it assigned */
777 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
778 if (((res->start - offset) & 0xfffffffful) != 0)
779 return 0;
781 /* Here, we are a bit different than memory as typically IO
782 * space starting at low addresses -is- valid. What we do
783 * instead if that we consider as unassigned anything that
784 * doesn't have IO enabled in the PCI command register,
785 * and that's it.
787 pci_read_config_word(dev, PCI_COMMAND, &command);
788 if (command & PCI_COMMAND_IO)
789 return 0;
791 /* It's starting at 0 and IO is disabled in the bridge, consider
792 * it unassigned
794 return 1;
798 /* Fixup resources of a PCI<->PCI bridge */
799 static void pcibios_fixup_bridge(struct pci_bus *bus)
801 struct resource *res;
802 int i;
804 struct pci_dev *dev = bus->self;
806 pci_bus_for_each_resource(bus, res, i) {
807 if (!res)
808 continue;
809 if (!res->flags)
810 continue;
811 if (i >= 3 && bus->self->transparent)
812 continue;
814 pr_debug("PCI:%s Bus rsrc %d %016llx-%016llx [%x] fixup...\n",
815 pci_name(dev), i,
816 (unsigned long long)res->start,
817 (unsigned long long)res->end,
818 (unsigned int)res->flags);
820 /* Try to detect uninitialized P2P bridge resources,
821 * and clear them out so they get re-assigned later
823 if (pcibios_uninitialized_bridge_resource(bus, res)) {
824 res->flags = 0;
825 pr_debug("PCI:%s (unassigned)\n",
826 pci_name(dev));
827 } else {
828 pr_debug("PCI:%s %016llx-%016llx\n",
829 pci_name(dev),
830 (unsigned long long)res->start,
831 (unsigned long long)res->end);
836 void pcibios_setup_bus_self(struct pci_bus *bus)
838 /* Fix up the bus resources for P2P bridges */
839 if (bus->self != NULL)
840 pcibios_fixup_bridge(bus);
843 void pcibios_setup_bus_devices(struct pci_bus *bus)
845 struct pci_dev *dev;
847 pr_debug("PCI: Fixup bus devices %d (%s)\n",
848 bus->number, bus->self ? pci_name(bus->self) : "PHB");
850 list_for_each_entry(dev, &bus->devices, bus_list) {
851 /* Setup OF node pointer in archdata */
852 dev->dev.of_node = pci_device_to_OF_node(dev);
854 /* Fixup NUMA node as it may not be setup yet by the generic
855 * code and is needed by the DMA init
857 set_dev_node(&dev->dev, pcibus_to_node(dev->bus));
859 /* Read default IRQs and fixup if necessary */
860 dev->irq = of_irq_parse_and_map_pci(dev, 0, 0);
864 void pcibios_fixup_bus(struct pci_bus *bus)
866 /* When called from the generic PCI probe, read PCI<->PCI bridge
867 * bases. This is -not- called when generating the PCI tree from
868 * the OF device-tree.
870 if (bus->self != NULL)
871 pci_read_bridge_bases(bus);
873 /* Now fixup the bus bus */
874 pcibios_setup_bus_self(bus);
876 /* Now fixup devices on that bus */
877 pcibios_setup_bus_devices(bus);
879 EXPORT_SYMBOL(pcibios_fixup_bus);
881 static int skip_isa_ioresource_align(struct pci_dev *dev)
883 return 0;
887 * We need to avoid collisions with `mirrored' VGA ports
888 * and other strange ISA hardware, so we always want the
889 * addresses to be allocated in the 0x000-0x0ff region
890 * modulo 0x400.
892 * Why? Because some silly external IO cards only decode
893 * the low 10 bits of the IO address. The 0x00-0xff region
894 * is reserved for motherboard devices that decode all 16
895 * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
896 * but we want to try to avoid allocating at 0x2900-0x2bff
897 * which might have be mirrored at 0x0100-0x03ff..
899 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
900 resource_size_t size, resource_size_t align)
902 struct pci_dev *dev = data;
903 resource_size_t start = res->start;
905 if (res->flags & IORESOURCE_IO) {
906 if (skip_isa_ioresource_align(dev))
907 return start;
908 if (start & 0x300)
909 start = (start + 0x3ff) & ~0x3ff;
912 return start;
914 EXPORT_SYMBOL(pcibios_align_resource);
917 * Reparent resource children of pr that conflict with res
918 * under res, and make res replace those children.
920 static int __init reparent_resources(struct resource *parent,
921 struct resource *res)
923 struct resource *p, **pp;
924 struct resource **firstpp = NULL;
926 for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
927 if (p->end < res->start)
928 continue;
929 if (res->end < p->start)
930 break;
931 if (p->start < res->start || p->end > res->end)
932 return -1; /* not completely contained */
933 if (firstpp == NULL)
934 firstpp = pp;
936 if (firstpp == NULL)
937 return -1; /* didn't find any conflicting entries? */
938 res->parent = parent;
939 res->child = *firstpp;
940 res->sibling = *pp;
941 *firstpp = res;
942 *pp = NULL;
943 for (p = res->child; p != NULL; p = p->sibling) {
944 p->parent = res;
945 pr_debug("PCI: Reparented %s [%llx..%llx] under %s\n",
946 p->name,
947 (unsigned long long)p->start,
948 (unsigned long long)p->end, res->name);
950 return 0;
954 * Handle resources of PCI devices. If the world were perfect, we could
955 * just allocate all the resource regions and do nothing more. It isn't.
956 * On the other hand, we cannot just re-allocate all devices, as it would
957 * require us to know lots of host bridge internals. So we attempt to
958 * keep as much of the original configuration as possible, but tweak it
959 * when it's found to be wrong.
961 * Known BIOS problems we have to work around:
962 * - I/O or memory regions not configured
963 * - regions configured, but not enabled in the command register
964 * - bogus I/O addresses above 64K used
965 * - expansion ROMs left enabled (this may sound harmless, but given
966 * the fact the PCI specs explicitly allow address decoders to be
967 * shared between expansion ROMs and other resource regions, it's
968 * at least dangerous)
970 * Our solution:
971 * (1) Allocate resources for all buses behind PCI-to-PCI bridges.
972 * This gives us fixed barriers on where we can allocate.
973 * (2) Allocate resources for all enabled devices. If there is
974 * a collision, just mark the resource as unallocated. Also
975 * disable expansion ROMs during this step.
976 * (3) Try to allocate resources for disabled devices. If the
977 * resources were assigned correctly, everything goes well,
978 * if they weren't, they won't disturb allocation of other
979 * resources.
980 * (4) Assign new addresses to resources which were either
981 * not configured at all or misconfigured. If explicitly
982 * requested by the user, configure expansion ROM address
983 * as well.
986 static void pcibios_allocate_bus_resources(struct pci_bus *bus)
988 struct pci_bus *b;
989 int i;
990 struct resource *res, *pr;
992 pr_debug("PCI: Allocating bus resources for %04x:%02x...\n",
993 pci_domain_nr(bus), bus->number);
995 pci_bus_for_each_resource(bus, res, i) {
996 if (!res || !res->flags
997 || res->start > res->end || res->parent)
998 continue;
999 if (bus->parent == NULL)
1000 pr = (res->flags & IORESOURCE_IO) ?
1001 &ioport_resource : &iomem_resource;
1002 else {
1003 /* Don't bother with non-root busses when
1004 * re-assigning all resources. We clear the
1005 * resource flags as if they were colliding
1006 * and as such ensure proper re-allocation
1007 * later.
1009 pr = pci_find_parent_resource(bus->self, res);
1010 if (pr == res) {
1011 /* this happens when the generic PCI
1012 * code (wrongly) decides that this
1013 * bridge is transparent -- paulus
1015 continue;
1019 pr_debug("PCI: %s (bus %d) bridge rsrc %d: %016llx-%016llx ",
1020 bus->self ? pci_name(bus->self) : "PHB",
1021 bus->number, i,
1022 (unsigned long long)res->start,
1023 (unsigned long long)res->end);
1024 pr_debug("[0x%x], parent %p (%s)\n",
1025 (unsigned int)res->flags,
1026 pr, (pr && pr->name) ? pr->name : "nil");
1028 if (pr && !(pr->flags & IORESOURCE_UNSET)) {
1029 if (request_resource(pr, res) == 0)
1030 continue;
1032 * Must be a conflict with an existing entry.
1033 * Move that entry (or entries) under the
1034 * bridge resource and try again.
1036 if (reparent_resources(pr, res) == 0)
1037 continue;
1039 pr_warn("PCI: Cannot allocate resource region ");
1040 pr_cont("%d of PCI bridge %d, will remap\n", i, bus->number);
1041 res->start = res->end = 0;
1042 res->flags = 0;
1045 list_for_each_entry(b, &bus->children, node)
1046 pcibios_allocate_bus_resources(b);
1049 static inline void alloc_resource(struct pci_dev *dev, int idx)
1051 struct resource *pr, *r = &dev->resource[idx];
1053 pr_debug("PCI: Allocating %s: Resource %d: %016llx..%016llx [%x]\n",
1054 pci_name(dev), idx,
1055 (unsigned long long)r->start,
1056 (unsigned long long)r->end,
1057 (unsigned int)r->flags);
1059 pr = pci_find_parent_resource(dev, r);
1060 if (!pr || (pr->flags & IORESOURCE_UNSET) ||
1061 request_resource(pr, r) < 0) {
1062 pr_warn("PCI: Cannot allocate resource region %d ", idx);
1063 pr_cont("of device %s, will remap\n", pci_name(dev));
1064 if (pr)
1065 pr_debug("PCI: parent is %p: %016llx-%016llx [%x]\n",
1067 (unsigned long long)pr->start,
1068 (unsigned long long)pr->end,
1069 (unsigned int)pr->flags);
1070 /* We'll assign a new address later */
1071 r->flags |= IORESOURCE_UNSET;
1072 r->end -= r->start;
1073 r->start = 0;
1077 static void __init pcibios_allocate_resources(int pass)
1079 struct pci_dev *dev = NULL;
1080 int idx, disabled;
1081 u16 command;
1082 struct resource *r;
1084 for_each_pci_dev(dev) {
1085 pci_read_config_word(dev, PCI_COMMAND, &command);
1086 for (idx = 0; idx <= PCI_ROM_RESOURCE; idx++) {
1087 r = &dev->resource[idx];
1088 if (r->parent) /* Already allocated */
1089 continue;
1090 if (!r->flags || (r->flags & IORESOURCE_UNSET))
1091 continue; /* Not assigned at all */
1092 /* We only allocate ROMs on pass 1 just in case they
1093 * have been screwed up by firmware
1095 if (idx == PCI_ROM_RESOURCE)
1096 disabled = 1;
1097 if (r->flags & IORESOURCE_IO)
1098 disabled = !(command & PCI_COMMAND_IO);
1099 else
1100 disabled = !(command & PCI_COMMAND_MEMORY);
1101 if (pass == disabled)
1102 alloc_resource(dev, idx);
1104 if (pass)
1105 continue;
1106 r = &dev->resource[PCI_ROM_RESOURCE];
1107 if (r->flags) {
1108 /* Turn the ROM off, leave the resource region,
1109 * but keep it unregistered.
1111 u32 reg;
1112 pci_read_config_dword(dev, dev->rom_base_reg, &reg);
1113 if (reg & PCI_ROM_ADDRESS_ENABLE) {
1114 pr_debug("PCI: Switching off ROM of %s\n",
1115 pci_name(dev));
1116 r->flags &= ~IORESOURCE_ROM_ENABLE;
1117 pci_write_config_dword(dev, dev->rom_base_reg,
1118 reg & ~PCI_ROM_ADDRESS_ENABLE);
1124 static void __init pcibios_reserve_legacy_regions(struct pci_bus *bus)
1126 struct pci_controller *hose = pci_bus_to_host(bus);
1127 resource_size_t offset;
1128 struct resource *res, *pres;
1129 int i;
1131 pr_debug("Reserving legacy ranges for domain %04x\n",
1132 pci_domain_nr(bus));
1134 /* Check for IO */
1135 if (!(hose->io_resource.flags & IORESOURCE_IO))
1136 goto no_io;
1137 offset = (unsigned long)hose->io_base_virt - _IO_BASE;
1138 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
1139 BUG_ON(res == NULL);
1140 res->name = "Legacy IO";
1141 res->flags = IORESOURCE_IO;
1142 res->start = offset;
1143 res->end = (offset + 0xfff) & 0xfffffffful;
1144 pr_debug("Candidate legacy IO: %pR\n", res);
1145 if (request_resource(&hose->io_resource, res)) {
1146 pr_debug("PCI %04x:%02x Cannot reserve Legacy IO %pR\n",
1147 pci_domain_nr(bus), bus->number, res);
1148 kfree(res);
1151 no_io:
1152 /* Check for memory */
1153 offset = hose->pci_mem_offset;
1154 pr_debug("hose mem offset: %016llx\n", (unsigned long long)offset);
1155 for (i = 0; i < 3; i++) {
1156 pres = &hose->mem_resources[i];
1157 if (!(pres->flags & IORESOURCE_MEM))
1158 continue;
1159 pr_debug("hose mem res: %pR\n", pres);
1160 if ((pres->start - offset) <= 0xa0000 &&
1161 (pres->end - offset) >= 0xbffff)
1162 break;
1164 if (i >= 3)
1165 return;
1166 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
1167 BUG_ON(res == NULL);
1168 res->name = "Legacy VGA memory";
1169 res->flags = IORESOURCE_MEM;
1170 res->start = 0xa0000 + offset;
1171 res->end = 0xbffff + offset;
1172 pr_debug("Candidate VGA memory: %pR\n", res);
1173 if (request_resource(pres, res)) {
1174 pr_debug("PCI %04x:%02x Cannot reserve VGA memory %pR\n",
1175 pci_domain_nr(bus), bus->number, res);
1176 kfree(res);
1180 void __init pcibios_resource_survey(void)
1182 struct pci_bus *b;
1184 /* Allocate and assign resources. If we re-assign everything, then
1185 * we skip the allocate phase
1187 list_for_each_entry(b, &pci_root_buses, node)
1188 pcibios_allocate_bus_resources(b);
1190 pcibios_allocate_resources(0);
1191 pcibios_allocate_resources(1);
1193 /* Before we start assigning unassigned resource, we try to reserve
1194 * the low IO area and the VGA memory area if they intersect the
1195 * bus available resources to avoid allocating things on top of them
1197 list_for_each_entry(b, &pci_root_buses, node)
1198 pcibios_reserve_legacy_regions(b);
1200 /* Now proceed to assigning things that were left unassigned */
1201 pr_debug("PCI: Assigning unassigned resources...\n");
1202 pci_assign_unassigned_resources();
1205 /* This is used by the PCI hotplug driver to allocate resource
1206 * of newly plugged busses. We can try to consolidate with the
1207 * rest of the code later, for now, keep it as-is as our main
1208 * resource allocation function doesn't deal with sub-trees yet.
1210 void pcibios_claim_one_bus(struct pci_bus *bus)
1212 struct pci_dev *dev;
1213 struct pci_bus *child_bus;
1215 list_for_each_entry(dev, &bus->devices, bus_list) {
1216 int i;
1218 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
1219 struct resource *r = &dev->resource[i];
1221 if (r->parent || !r->start || !r->flags)
1222 continue;
1224 pr_debug("PCI: Claiming %s: ", pci_name(dev));
1225 pr_debug("Resource %d: %016llx..%016llx [%x]\n",
1226 i, (unsigned long long)r->start,
1227 (unsigned long long)r->end,
1228 (unsigned int)r->flags);
1230 pci_claim_resource(dev, i);
1234 list_for_each_entry(child_bus, &bus->children, node)
1235 pcibios_claim_one_bus(child_bus);
1237 EXPORT_SYMBOL_GPL(pcibios_claim_one_bus);
1240 /* pcibios_finish_adding_to_bus
1242 * This is to be called by the hotplug code after devices have been
1243 * added to a bus, this include calling it for a PHB that is just
1244 * being added
1246 void pcibios_finish_adding_to_bus(struct pci_bus *bus)
1248 pr_debug("PCI: Finishing adding to hotplug bus %04x:%02x\n",
1249 pci_domain_nr(bus), bus->number);
1251 /* Allocate bus and devices resources */
1252 pcibios_allocate_bus_resources(bus);
1253 pcibios_claim_one_bus(bus);
1255 /* Add new devices to global lists. Register in proc, sysfs. */
1256 pci_bus_add_devices(bus);
1258 /* Fixup EEH */
1259 /* eeh_add_device_tree_late(bus); */
1261 EXPORT_SYMBOL_GPL(pcibios_finish_adding_to_bus);
1263 static void pcibios_setup_phb_resources(struct pci_controller *hose,
1264 struct list_head *resources)
1266 unsigned long io_offset;
1267 struct resource *res;
1268 int i;
1270 /* Hookup PHB IO resource */
1271 res = &hose->io_resource;
1273 /* Fixup IO space offset */
1274 io_offset = (unsigned long)hose->io_base_virt - isa_io_base;
1275 res->start = (res->start + io_offset) & 0xffffffffu;
1276 res->end = (res->end + io_offset) & 0xffffffffu;
1278 if (!res->flags) {
1279 pr_warn("PCI: I/O resource not set for host ");
1280 pr_cont("bridge %s (domain %d)\n",
1281 hose->dn->full_name, hose->global_number);
1282 /* Workaround for lack of IO resource only on 32-bit */
1283 res->start = (unsigned long)hose->io_base_virt - isa_io_base;
1284 res->end = res->start + IO_SPACE_LIMIT;
1285 res->flags = IORESOURCE_IO;
1287 pci_add_resource_offset(resources, res,
1288 (__force resource_size_t)(hose->io_base_virt - _IO_BASE));
1290 pr_debug("PCI: PHB IO resource = %016llx-%016llx [%lx]\n",
1291 (unsigned long long)res->start,
1292 (unsigned long long)res->end,
1293 (unsigned long)res->flags);
1295 /* Hookup PHB Memory resources */
1296 for (i = 0; i < 3; ++i) {
1297 res = &hose->mem_resources[i];
1298 if (!res->flags) {
1299 if (i > 0)
1300 continue;
1301 pr_err("PCI: Memory resource 0 not set for ");
1302 pr_cont("host bridge %s (domain %d)\n",
1303 hose->dn->full_name, hose->global_number);
1305 /* Workaround for lack of MEM resource only on 32-bit */
1306 res->start = hose->pci_mem_offset;
1307 res->end = (resource_size_t)-1LL;
1308 res->flags = IORESOURCE_MEM;
1311 pci_add_resource_offset(resources, res, hose->pci_mem_offset);
1313 pr_debug("PCI: PHB MEM resource %d = %016llx-%016llx [%lx]\n",
1314 i, (unsigned long long)res->start,
1315 (unsigned long long)res->end,
1316 (unsigned long)res->flags);
1319 pr_debug("PCI: PHB MEM offset = %016llx\n",
1320 (unsigned long long)hose->pci_mem_offset);
1321 pr_debug("PCI: PHB IO offset = %08lx\n",
1322 (unsigned long)hose->io_base_virt - _IO_BASE);
1325 struct device_node *pcibios_get_phb_of_node(struct pci_bus *bus)
1327 struct pci_controller *hose = bus->sysdata;
1329 return of_node_get(hose->dn);
1332 static void pcibios_scan_phb(struct pci_controller *hose)
1334 LIST_HEAD(resources);
1335 struct pci_bus *bus;
1336 struct device_node *node = hose->dn;
1338 pr_debug("PCI: Scanning PHB %s\n", of_node_full_name(node));
1340 pcibios_setup_phb_resources(hose, &resources);
1342 bus = pci_scan_root_bus(hose->parent, hose->first_busno,
1343 hose->ops, hose, &resources);
1344 if (bus == NULL) {
1345 pr_err("Failed to create bus for PCI domain %04x\n",
1346 hose->global_number);
1347 pci_free_resource_list(&resources);
1348 return;
1350 bus->busn_res.start = hose->first_busno;
1351 hose->bus = bus;
1353 hose->last_busno = bus->busn_res.end;
1356 static int __init pcibios_init(void)
1358 struct pci_controller *hose, *tmp;
1359 int next_busno = 0;
1361 pr_info("PCI: Probing PCI hardware\n");
1363 /* Scan all of the recorded PCI controllers. */
1364 list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
1365 hose->last_busno = 0xff;
1366 pcibios_scan_phb(hose);
1367 if (next_busno <= hose->last_busno)
1368 next_busno = hose->last_busno + 1;
1370 pci_bus_count = next_busno;
1372 /* Call common code to handle resource allocation */
1373 pcibios_resource_survey();
1375 return 0;
1378 subsys_initcall(pcibios_init);
1380 static struct pci_controller *pci_bus_to_hose(int bus)
1382 struct pci_controller *hose, *tmp;
1384 list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
1385 if (bus >= hose->first_busno && bus <= hose->last_busno)
1386 return hose;
1387 return NULL;
1390 /* Provide information on locations of various I/O regions in physical
1391 * memory. Do this on a per-card basis so that we choose the right
1392 * root bridge.
1393 * Note that the returned IO or memory base is a physical address
1396 long sys_pciconfig_iobase(long which, unsigned long bus, unsigned long devfn)
1398 struct pci_controller *hose;
1399 long result = -EOPNOTSUPP;
1401 hose = pci_bus_to_hose(bus);
1402 if (!hose)
1403 return -ENODEV;
1405 switch (which) {
1406 case IOBASE_BRIDGE_NUMBER:
1407 return (long)hose->first_busno;
1408 case IOBASE_MEMORY:
1409 return (long)hose->pci_mem_offset;
1410 case IOBASE_IO:
1411 return (long)hose->io_base_phys;
1412 case IOBASE_ISA_IO:
1413 return (long)isa_io_base;
1414 case IOBASE_ISA_MEM:
1415 return (long)isa_mem_base;
1418 return result;
1422 * Null PCI config access functions, for the case when we can't
1423 * find a hose.
1425 #define NULL_PCI_OP(rw, size, type) \
1426 static int \
1427 null_##rw##_config_##size(struct pci_dev *dev, int offset, type val) \
1429 return PCIBIOS_DEVICE_NOT_FOUND; \
1432 static int
1433 null_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
1434 int len, u32 *val)
1436 return PCIBIOS_DEVICE_NOT_FOUND;
1439 static int
1440 null_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
1441 int len, u32 val)
1443 return PCIBIOS_DEVICE_NOT_FOUND;
1446 static struct pci_ops null_pci_ops = {
1447 .read = null_read_config,
1448 .write = null_write_config,
1452 * These functions are used early on before PCI scanning is done
1453 * and all of the pci_dev and pci_bus structures have been created.
1455 static struct pci_bus *
1456 fake_pci_bus(struct pci_controller *hose, int busnr)
1458 static struct pci_bus bus;
1460 if (!hose)
1461 pr_err("Can't find hose for PCI bus %d!\n", busnr);
1463 bus.number = busnr;
1464 bus.sysdata = hose;
1465 bus.ops = hose ? hose->ops : &null_pci_ops;
1466 return &bus;
1469 #define EARLY_PCI_OP(rw, size, type) \
1470 int early_##rw##_config_##size(struct pci_controller *hose, int bus, \
1471 int devfn, int offset, type value) \
1473 return pci_bus_##rw##_config_##size(fake_pci_bus(hose, bus), \
1474 devfn, offset, value); \
1477 EARLY_PCI_OP(read, byte, u8 *)
1478 EARLY_PCI_OP(read, word, u16 *)
1479 EARLY_PCI_OP(read, dword, u32 *)
1480 EARLY_PCI_OP(write, byte, u8)
1481 EARLY_PCI_OP(write, word, u16)
1482 EARLY_PCI_OP(write, dword, u32)
1484 int early_find_capability(struct pci_controller *hose, int bus, int devfn,
1485 int cap)
1487 return pci_bus_find_capability(fake_pci_bus(hose, bus), devfn, cap);