powerpc/pci: Improve detection of unassigned bridge resources

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / powerpc / kernel / pci-common.c

/*
 * Contains common pci routines for ALL ppc platform
 * (based on pci_32.c and pci_64.c)
 *
 * Port for PPC64 David Engebretsen, IBM Corp.
 * Contains common pci routines for ppc64 platform, pSeries and iSeries brands.
 *
 * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
 *   Rework, based on alpha PCI code.
 *
 * Common pmac/prep/chrp pci routines. -- Cort
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#undef DEBUG

#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mm.h>
#include <linux/list.h>
#include <linux/syscalls.h>
#include <linux/irq.h>
#include <linux/vmalloc.h>

#include <asm/processor.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/byteorder.h>
#include <asm/machdep.h>
#include <asm/ppc-pci.h>
#include <asm/firmware.h>

#ifdef DEBUG
#include <asm/udbg.h>
#define DBG(fmt...) printk(fmt)
#else
#define DBG(fmt...)
#endif

static DEFINE_SPINLOCK(hose_spinlock);

/* XXX kill that some day ... */
static int global_phb_number;           /* Global phb counter */

/* ISA Memory physical address */
resource_size_t isa_mem_base;

/* Default PCI flags is 0 */
unsigned int ppc_pci_flags;

static struct dma_mapping_ops *pci_dma_ops;

void set_pci_dma_ops(struct dma_mapping_ops *dma_ops)
{
        pci_dma_ops = dma_ops;
}

struct dma_mapping_ops *get_pci_dma_ops(void)
{
        return pci_dma_ops;
}
EXPORT_SYMBOL(get_pci_dma_ops);

int pci_set_dma_mask(struct pci_dev *dev, u64 mask)
{
        return dma_set_mask(&dev->dev, mask);
}

int pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
{
        int rc;

        rc = dma_set_mask(&dev->dev, mask);
        dev->dev.coherent_dma_mask = dev->dma_mask;

        return rc;
}

struct pci_controller *pcibios_alloc_controller(struct device_node *dev)
{
        struct pci_controller *phb;

        phb = zalloc_maybe_bootmem(sizeof(struct pci_controller), GFP_KERNEL);
        if (phb == NULL)
                return NULL;
        spin_lock(&hose_spinlock);
        phb->global_number = global_phb_number++;
        list_add_tail(&phb->list_node, &hose_list);
        spin_unlock(&hose_spinlock);
        phb->dn = dev;
        phb->is_dynamic = mem_init_done;
#ifdef CONFIG_PPC64
        if (dev) {
                int nid = of_node_to_nid(dev);

                if (nid < 0 || !node_online(nid))
                        nid = -1;

                PHB_SET_NODE(phb, nid);
        }
#endif
        return phb;
}

void pcibios_free_controller(struct pci_controller *phb)
{
        spin_lock(&hose_spinlock);
        list_del(&phb->list_node);
        spin_unlock(&hose_spinlock);

        if (phb->is_dynamic)
                kfree(phb);
}

int pcibios_vaddr_is_ioport(void __iomem *address)
{
        int ret = 0;
        struct pci_controller *hose;
        unsigned long size;

        spin_lock(&hose_spinlock);
        list_for_each_entry(hose, &hose_list, list_node) {
#ifdef CONFIG_PPC64
                size = hose->pci_io_size;
#else
                size = hose->io_resource.end - hose->io_resource.start + 1;
#endif
                if (address >= hose->io_base_virt &&
                    address < (hose->io_base_virt + size)) {
                        ret = 1;
                        break;
                }
        }
        spin_unlock(&hose_spinlock);
        return ret;
}

/*
 * Return the domain number for this bus.
 */
int pci_domain_nr(struct pci_bus *bus)
{
        struct pci_controller *hose = pci_bus_to_host(bus);

        return hose->global_number;
}
EXPORT_SYMBOL(pci_domain_nr);

#ifdef CONFIG_PPC_OF

/* This routine is meant to be used early during boot, when the
 * PCI bus numbers have not yet been assigned, and you need to
 * issue PCI config cycles to an OF device.
 * It could also be used to "fix" RTAS config cycles if you want
 * to set pci_assign_all_buses to 1 and still use RTAS for PCI
 * config cycles.
 */
struct pci_controller* pci_find_hose_for_OF_device(struct device_node* node)
{
        if (!have_of)
                return NULL;
        while(node) {
                struct pci_controller *hose, *tmp;
                list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
                        if (hose->dn == node)
                                return hose;
                node = node->parent;
        }
        return NULL;
}

static ssize_t pci_show_devspec(struct device *dev,
                struct device_attribute *attr, char *buf)
{
        struct pci_dev *pdev;
        struct device_node *np;

        pdev = to_pci_dev (dev);
        np = pci_device_to_OF_node(pdev);
        if (np == NULL || np->full_name == NULL)
                return 0;
        return sprintf(buf, "%s", np->full_name);
}
static DEVICE_ATTR(devspec, S_IRUGO, pci_show_devspec, NULL);
#endif /* CONFIG_PPC_OF */

/* Add sysfs properties */
int pcibios_add_platform_entries(struct pci_dev *pdev)
{
#ifdef CONFIG_PPC_OF
        return device_create_file(&pdev->dev, &dev_attr_devspec);
#else
        return 0;
#endif /* CONFIG_PPC_OF */

}

char __devinit *pcibios_setup(char *str)
{
        return str;
}

void __devinit pcibios_setup_new_device(struct pci_dev *dev)
{
        struct dev_archdata *sd = &dev->dev.archdata;

        sd->of_node = pci_device_to_OF_node(dev);

        DBG("PCI: device %s OF node: %s\n", pci_name(dev),
            sd->of_node ? sd->of_node->full_name : "<none>");

        sd->dma_ops = pci_dma_ops;
#ifdef CONFIG_PPC32
        sd->dma_data = (void *)PCI_DRAM_OFFSET;
#endif
        set_dev_node(&dev->dev, pcibus_to_node(dev->bus));

        if (ppc_md.pci_dma_dev_setup)
                ppc_md.pci_dma_dev_setup(dev);
}
EXPORT_SYMBOL(pcibios_setup_new_device);

/*
 * Reads the interrupt pin to determine if interrupt is use by card.
 * If the interrupt is used, then gets the interrupt line from the
 * openfirmware and sets it in the pci_dev and pci_config line.
 */
int pci_read_irq_line(struct pci_dev *pci_dev)
{
        struct of_irq oirq;
        unsigned int virq;

        /* The current device-tree that iSeries generates from the HV
         * PCI informations doesn't contain proper interrupt routing,
         * and all the fallback would do is print out crap, so we
         * don't attempt to resolve the interrupts here at all, some
         * iSeries specific fixup does it.
         *
         * In the long run, we will hopefully fix the generated device-tree
         * instead.
         */
#ifdef CONFIG_PPC_ISERIES
        if (firmware_has_feature(FW_FEATURE_ISERIES))
                return -1;
#endif

        DBG("Try to map irq for %s...\n", pci_name(pci_dev));

#ifdef DEBUG
        memset(&oirq, 0xff, sizeof(oirq));
#endif
        /* Try to get a mapping from the device-tree */
        if (of_irq_map_pci(pci_dev, &oirq)) {
                u8 line, pin;

                /* If that fails, lets fallback to what is in the config
                 * space and map that through the default controller. We
                 * also set the type to level low since that's what PCI
                 * interrupts are. If your platform does differently, then
                 * either provide a proper interrupt tree or don't use this
                 * function.
                 */
                if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_PIN, &pin))
                        return -1;
                if (pin == 0)
                        return -1;
                if (pci_read_config_byte(pci_dev, PCI_INTERRUPT_LINE, &line) ||
                    line == 0xff || line == 0) {
                        return -1;
                }
                DBG(" -> no map ! Using line %d (pin %d) from PCI config\n",
                    line, pin);

                virq = irq_create_mapping(NULL, line);
                if (virq != NO_IRQ)
                        set_irq_type(virq, IRQ_TYPE_LEVEL_LOW);
        } else {
                DBG(" -> got one, spec %d cells (0x%08x 0x%08x...) on %s\n",
                    oirq.size, oirq.specifier[0], oirq.specifier[1],
                    oirq.controller->full_name);

                virq = irq_create_of_mapping(oirq.controller, oirq.specifier,
                                             oirq.size);
        }
        if(virq == NO_IRQ) {
                DBG(" -> failed to map !\n");
                return -1;
        }

        DBG(" -> mapped to linux irq %d\n", virq);

        pci_dev->irq = virq;

        return 0;
}
EXPORT_SYMBOL(pci_read_irq_line);

/*
 * Platform support for /proc/bus/pci/X/Y mmap()s,
 * modelled on the sparc64 implementation by Dave Miller.
 *  -- paulus.
 */

/*
 * Adjust vm_pgoff of VMA such that it is the physical page offset
 * corresponding to the 32-bit pci bus offset for DEV requested by the user.
 *
 * Basically, the user finds the base address for his device which he wishes
 * to mmap.  They read the 32-bit value from the config space base register,
 * add whatever PAGE_SIZE multiple offset they wish, and feed this into the
 * offset parameter of mmap on /proc/bus/pci/XXX for that device.
 *
 * Returns negative error code on failure, zero on success.
 */
static struct resource *__pci_mmap_make_offset(struct pci_dev *dev,
                                               resource_size_t *offset,
                                               enum pci_mmap_state mmap_state)
{
        struct pci_controller *hose = pci_bus_to_host(dev->bus);
        unsigned long io_offset = 0;
        int i, res_bit;

        if (hose == 0)
                return NULL;            /* should never happen */

        /* If memory, add on the PCI bridge address offset */
        if (mmap_state == pci_mmap_mem) {
#if 0 /* See comment in pci_resource_to_user() for why this is disabled */
                *offset += hose->pci_mem_offset;
#endif
                res_bit = IORESOURCE_MEM;
        } else {
                io_offset = (unsigned long)hose->io_base_virt - _IO_BASE;
                *offset += io_offset;
                res_bit = IORESOURCE_IO;
        }

        /*
         * Check that the offset requested corresponds to one of the
         * resources of the device.
         */
        for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
                struct resource *rp = &dev->resource[i];
                int flags = rp->flags;

                /* treat ROM as memory (should be already) */
                if (i == PCI_ROM_RESOURCE)
                        flags |= IORESOURCE_MEM;

                /* Active and same type? */
                if ((flags & res_bit) == 0)
                        continue;

                /* In the range of this resource? */
                if (*offset < (rp->start & PAGE_MASK) || *offset > rp->end)
                        continue;

                /* found it! construct the final physical address */
                if (mmap_state == pci_mmap_io)
                        *offset += hose->io_base_phys - io_offset;
                return rp;
        }

        return NULL;
}

/*
 * Set vm_page_prot of VMA, as appropriate for this architecture, for a pci
 * device mapping.
 */
static pgprot_t __pci_mmap_set_pgprot(struct pci_dev *dev, struct resource *rp,
                                      pgprot_t protection,
                                      enum pci_mmap_state mmap_state,
                                      int write_combine)
{
        unsigned long prot = pgprot_val(protection);

        /* Write combine is always 0 on non-memory space mappings. On
         * memory space, if the user didn't pass 1, we check for a
         * "prefetchable" resource. This is a bit hackish, but we use
         * this to workaround the inability of /sysfs to provide a write
         * combine bit
         */
        if (mmap_state != pci_mmap_mem)
                write_combine = 0;
        else if (write_combine == 0) {
                if (rp->flags & IORESOURCE_PREFETCH)
                        write_combine = 1;
        }

        /* XXX would be nice to have a way to ask for write-through */
        prot |= _PAGE_NO_CACHE;
        if (write_combine)
                prot &= ~_PAGE_GUARDED;
        else
                prot |= _PAGE_GUARDED;

        return __pgprot(prot);
}

/*
 * This one is used by /dev/mem and fbdev who have no clue about the
 * PCI device, it tries to find the PCI device first and calls the
 * above routine
 */
pgprot_t pci_phys_mem_access_prot(struct file *file,
                                  unsigned long pfn,
                                  unsigned long size,
                                  pgprot_t protection)
{
        struct pci_dev *pdev = NULL;
        struct resource *found = NULL;
        unsigned long prot = pgprot_val(protection);
        resource_size_t offset = ((resource_size_t)pfn) << PAGE_SHIFT;
        int i;

        if (page_is_ram(pfn))
                return __pgprot(prot);

        prot |= _PAGE_NO_CACHE | _PAGE_GUARDED;

        for_each_pci_dev(pdev) {
                for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
                        struct resource *rp = &pdev->resource[i];
                        int flags = rp->flags;

                        /* Active and same type? */
                        if ((flags & IORESOURCE_MEM) == 0)
                                continue;
                        /* In the range of this resource? */
                        if (offset < (rp->start & PAGE_MASK) ||
                            offset > rp->end)
                                continue;
                        found = rp;
                        break;
                }
                if (found)
                        break;
        }
        if (found) {
                if (found->flags & IORESOURCE_PREFETCH)
                        prot &= ~_PAGE_GUARDED;
                pci_dev_put(pdev);
        }

        DBG("non-PCI map for %lx, prot: %lx\n", offset, prot);

        return __pgprot(prot);
}


/*
 * Perform the actual remap of the pages for a PCI device mapping, as
 * appropriate for this architecture.  The region in the process to map
 * is described by vm_start and vm_end members of VMA, the base physical
 * address is found in vm_pgoff.
 * The pci device structure is provided so that architectures may make mapping
 * decisions on a per-device or per-bus basis.
 *
 * Returns a negative error code on failure, zero on success.
 */
int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
                        enum pci_mmap_state mmap_state, int write_combine)
{
        resource_size_t offset =
                ((resource_size_t)vma->vm_pgoff) << PAGE_SHIFT;
        struct resource *rp;
        int ret;

        rp = __pci_mmap_make_offset(dev, &offset, mmap_state);
        if (rp == NULL)
                return -EINVAL;

        vma->vm_pgoff = offset >> PAGE_SHIFT;
        vma->vm_page_prot = __pci_mmap_set_pgprot(dev, rp,
                                                  vma->vm_page_prot,
                                                  mmap_state, write_combine);

        ret = remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
                               vma->vm_end - vma->vm_start, vma->vm_page_prot);

        return ret;
}

void pci_resource_to_user(const struct pci_dev *dev, int bar,
                          const struct resource *rsrc,
                          resource_size_t *start, resource_size_t *end)
{
        struct pci_controller *hose = pci_bus_to_host(dev->bus);
        resource_size_t offset = 0;

        if (hose == NULL)
                return;

        if (rsrc->flags & IORESOURCE_IO)
                offset = (unsigned long)hose->io_base_virt - _IO_BASE;

        /* We pass a fully fixed up address to userland for MMIO instead of
         * a BAR value because X is lame and expects to be able to use that
         * to pass to /dev/mem !
         *
         * That means that we'll have potentially 64 bits values where some
         * userland apps only expect 32 (like X itself since it thinks only
         * Sparc has 64 bits MMIO) but if we don't do that, we break it on
         * 32 bits CHRPs :-(
         *
         * Hopefully, the sysfs insterface is immune to that gunk. Once X
         * has been fixed (and the fix spread enough), we can re-enable the
         * 2 lines below and pass down a BAR value to userland. In that case
         * we'll also have to re-enable the matching code in
         * __pci_mmap_make_offset().
         *
         * BenH.
         */
#if 0
        else if (rsrc->flags & IORESOURCE_MEM)
                offset = hose->pci_mem_offset;
#endif

        *start = rsrc->start - offset;
        *end = rsrc->end - offset;
}

/**
 * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
 * @hose: newly allocated pci_controller to be setup
 * @dev: device node of the host bridge
 * @primary: set if primary bus (32 bits only, soon to be deprecated)
 *
 * This function will parse the "ranges" property of a PCI host bridge device
 * node and setup the resource mapping of a pci controller based on its
 * content.
 *
 * Life would be boring if it wasn't for a few issues that we have to deal
 * with here:
 *
 *   - We can only cope with one IO space range and up to 3 Memory space
 *     ranges. However, some machines (thanks Apple !) tend to split their
 *     space into lots of small contiguous ranges. So we have to coalesce.
 *
 *   - We can only cope with all memory ranges having the same offset
 *     between CPU addresses and PCI addresses. Unfortunately, some bridges
 *     are setup for a large 1:1 mapping along with a small "window" which
 *     maps PCI address 0 to some arbitrary high address of the CPU space in
 *     order to give access to the ISA memory hole.
 *     The way out of here that I've chosen for now is to always set the
 *     offset based on the first resource found, then override it if we
 *     have a different offset and the previous was set by an ISA hole.
 *
 *   - Some busses have IO space not starting at 0, which causes trouble with
 *     the way we do our IO resource renumbering. The code somewhat deals with
 *     it for 64 bits but I would expect problems on 32 bits.
 *
 *   - Some 32 bits platforms such as 4xx can have physical space larger than
 *     32 bits so we need to use 64 bits values for the parsing
 */
void __devinit pci_process_bridge_OF_ranges(struct pci_controller *hose,
                                            struct device_node *dev,
                                            int primary)
{
        const u32 *ranges;
        int rlen;
        int pna = of_n_addr_cells(dev);
        int np = pna + 5;
        int memno = 0, isa_hole = -1;
        u32 pci_space;
        unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
        unsigned long long isa_mb = 0;
        struct resource *res;

        printk(KERN_INFO "PCI host bridge %s %s ranges:\n",
               dev->full_name, primary ? "(primary)" : "");

        /* Get ranges property */
        ranges = of_get_property(dev, "ranges", &rlen);
        if (ranges == NULL)
                return;

        /* Parse it */
        while ((rlen -= np * 4) >= 0) {
                /* Read next ranges element */
                pci_space = ranges[0];
                pci_addr = of_read_number(ranges + 1, 2);
                cpu_addr = of_translate_address(dev, ranges + 3);
                size = of_read_number(ranges + pna + 3, 2);
                ranges += np;
                if (cpu_addr == OF_BAD_ADDR || size == 0)
                        continue;

                /* Now consume following elements while they are contiguous */
                for (; rlen >= np * sizeof(u32);
                     ranges += np, rlen -= np * 4) {
                        if (ranges[0] != pci_space)
                                break;
                        pci_next = of_read_number(ranges + 1, 2);
                        cpu_next = of_translate_address(dev, ranges + 3);
                        if (pci_next != pci_addr + size ||
                            cpu_next != cpu_addr + size)
                                break;
                        size += of_read_number(ranges + pna + 3, 2);
                }

                /* Act based on address space type */
                res = NULL;
                switch ((pci_space >> 24) & 0x3) {
                case 1:         /* PCI IO space */
                        printk(KERN_INFO
                               "  IO 0x%016llx..0x%016llx -> 0x%016llx\n",
                               cpu_addr, cpu_addr + size - 1, pci_addr);

                        /* We support only one IO range */
                        if (hose->pci_io_size) {
                                printk(KERN_INFO
                                       " \\--> Skipped (too many) !\n");
                                continue;
                        }
#ifdef CONFIG_PPC32
                        /* On 32 bits, limit I/O space to 16MB */
                        if (size > 0x01000000)
                                size = 0x01000000;

                        /* 32 bits needs to map IOs here */
                        hose->io_base_virt = ioremap(cpu_addr, size);

                        /* Expect trouble if pci_addr is not 0 */
                        if (primary)
                                isa_io_base =
                                        (unsigned long)hose->io_base_virt;
#endif /* CONFIG_PPC32 */
                        /* pci_io_size and io_base_phys always represent IO
                         * space starting at 0 so we factor in pci_addr
                         */
                        hose->pci_io_size = pci_addr + size;
                        hose->io_base_phys = cpu_addr - pci_addr;

                        /* Build resource */
                        res = &hose->io_resource;
                        res->flags = IORESOURCE_IO;
                        res->start = pci_addr;
                        break;
                case 2:         /* PCI Memory space */
                case 3:         /* PCI 64 bits Memory space */
                        printk(KERN_INFO
                               " MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
                               cpu_addr, cpu_addr + size - 1, pci_addr,
                               (pci_space & 0x40000000) ? "Prefetch" : "");

                        /* We support only 3 memory ranges */
                        if (memno >= 3) {
                                printk(KERN_INFO
                                       " \\--> Skipped (too many) !\n");
                                continue;
                        }
                        /* Handles ISA memory hole space here */
                        if (pci_addr == 0) {
                                isa_mb = cpu_addr;
                                isa_hole = memno;
                                if (primary || isa_mem_base == 0)
                                        isa_mem_base = cpu_addr;
                        }

                        /* We get the PCI/Mem offset from the first range or
                         * the, current one if the offset came from an ISA
                         * hole. If they don't match, bugger.
                         */
                        if (memno == 0 ||
                            (isa_hole >= 0 && pci_addr != 0 &&
                             hose->pci_mem_offset == isa_mb))
                                hose->pci_mem_offset = cpu_addr - pci_addr;
                        else if (pci_addr != 0 &&
                                 hose->pci_mem_offset != cpu_addr - pci_addr) {
                                printk(KERN_INFO
                                       " \\--> Skipped (offset mismatch) !\n");
                                continue;
                        }

                        /* Build resource */
                        res = &hose->mem_resources[memno++];
                        res->flags = IORESOURCE_MEM;
                        if (pci_space & 0x40000000)
                                res->flags |= IORESOURCE_PREFETCH;
                        res->start = cpu_addr;
                        break;
                }
                if (res != NULL) {
                        res->name = dev->full_name;
                        res->end = res->start + size - 1;
                        res->parent = NULL;
                        res->sibling = NULL;
                        res->child = NULL;
                }
        }

        /* If there's an ISA hole and the pci_mem_offset is -not- matching
         * the ISA hole offset, then we need to remove the ISA hole from
         * the resource list for that brige
         */
        if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
                unsigned int next = isa_hole + 1;
                printk(KERN_INFO " Removing ISA hole at 0x%016llx\n", isa_mb);
                if (next < memno)
                        memmove(&hose->mem_resources[isa_hole],
                                &hose->mem_resources[next],
                                sizeof(struct resource) * (memno - next));
                hose->mem_resources[--memno].flags = 0;
        }
}

/* Decide whether to display the domain number in /proc */
int pci_proc_domain(struct pci_bus *bus)
{
        struct pci_controller *hose = pci_bus_to_host(bus);
#ifdef CONFIG_PPC64
        return hose->buid != 0;
#else
        if (!(ppc_pci_flags & PPC_PCI_ENABLE_PROC_DOMAINS))
                return 0;
        if (ppc_pci_flags & PPC_PCI_COMPAT_DOMAIN_0)
                return hose->global_number != 0;
        return 1;
#endif
}

void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
                             struct resource *res)
{
        resource_size_t offset = 0, mask = (resource_size_t)-1;
        struct pci_controller *hose = pci_bus_to_host(dev->bus);

        if (!hose)
                return;
        if (res->flags & IORESOURCE_IO) {
                offset = (unsigned long)hose->io_base_virt - _IO_BASE;
                mask = 0xffffffffu;
        } else if (res->flags & IORESOURCE_MEM)
                offset = hose->pci_mem_offset;

        region->start = (res->start - offset) & mask;
        region->end = (res->end - offset) & mask;
}
EXPORT_SYMBOL(pcibios_resource_to_bus);

void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
                             struct pci_bus_region *region)
{
        resource_size_t offset = 0, mask = (resource_size_t)-1;
        struct pci_controller *hose = pci_bus_to_host(dev->bus);

        if (!hose)
                return;
        if (res->flags & IORESOURCE_IO) {
                offset = (unsigned long)hose->io_base_virt - _IO_BASE;
                mask = 0xffffffffu;
        } else if (res->flags & IORESOURCE_MEM)
                offset = hose->pci_mem_offset;
        res->start = (region->start + offset) & mask;
        res->end = (region->end + offset) & mask;
}
EXPORT_SYMBOL(pcibios_bus_to_resource);

/* Fixup a bus resource into a linux resource */
static void __devinit fixup_resource(struct resource *res, struct pci_dev *dev)
{
        struct pci_controller *hose = pci_bus_to_host(dev->bus);
        resource_size_t offset = 0, mask = (resource_size_t)-1;

        if (res->flags & IORESOURCE_IO) {
                offset = (unsigned long)hose->io_base_virt - _IO_BASE;
                mask = 0xffffffffu;
        } else if (res->flags & IORESOURCE_MEM)
                offset = hose->pci_mem_offset;

        res->start = (res->start + offset) & mask;
        res->end = (res->end + offset) & mask;
}


/* This header fixup will do the resource fixup for all devices as they are
 * probed, but not for bridge ranges
 */
static void __devinit pcibios_fixup_resources(struct pci_dev *dev)
{
        struct pci_controller *hose = pci_bus_to_host(dev->bus);
        int i;

        if (!hose) {
                printk(KERN_ERR "No host bridge for PCI dev %s !\n",
                       pci_name(dev));
                return;
        }
        for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
                struct resource *res = dev->resource + i;
                if (!res->flags)
                        continue;
                /* On platforms that have PPC_PCI_PROBE_ONLY set, we don't
                 * consider 0 as an unassigned BAR value. It's technically
                 * a valid value, but linux doesn't like it... so when we can
                 * re-assign things, we do so, but if we can't, we keep it
                 * around and hope for the best...
                 */
                if (res->start == 0 && !(ppc_pci_flags & PPC_PCI_PROBE_ONLY)) {
                        pr_debug("PCI:%s Resource %d %016llx-%016llx [%x] is unassigned\n",
                                 pci_name(dev), i,
                                 (unsigned long long)res->start,
                                 (unsigned long long)res->end,
                                 (unsigned int)res->flags);
                        res->end -= res->start;
                        res->start = 0;
                        res->flags |= IORESOURCE_UNSET;
                        continue;
                }

                pr_debug("PCI:%s Resource %d %016llx-%016llx [%x] fixup...\n",
                         pci_name(dev), i,
                         (unsigned long long)res->start,\
                         (unsigned long long)res->end,
                         (unsigned int)res->flags);

                fixup_resource(res, dev);

                pr_debug("PCI:%s            %016llx-%016llx\n",
                         pci_name(dev),
                         (unsigned long long)res->start,
                         (unsigned long long)res->end);
        }

        /* Call machine specific resource fixup */
        if (ppc_md.pcibios_fixup_resources)
                ppc_md.pcibios_fixup_resources(dev);
}
DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pcibios_fixup_resources);

/* This function tries to figure out if a bridge resource has been initialized
 * by the firmware or not. It doesn't have to be absolutely bullet proof, but
 * things go more smoothly when it gets it right. It should covers cases such
 * as Apple "closed" bridge resources and bare-metal pSeries unassigned bridges
 */
static int __devinit pcibios_uninitialized_bridge_resource(struct pci_bus *bus,
                                                           struct resource *res)
{
        struct pci_controller *hose = pci_bus_to_host(bus);
        struct pci_dev *dev = bus->self;
        resource_size_t offset;
        u16 command;
        int i;

        /* We don't do anything if PCI_PROBE_ONLY is set */
        if (ppc_pci_flags & PPC_PCI_PROBE_ONLY)
                return 0;

        /* Job is a bit different between memory and IO */
        if (res->flags & IORESOURCE_MEM) {
                /* If the BAR is non-0 (res != pci_mem_offset) then it's probably been
                 * initialized by somebody
                 */
                if (res->start != hose->pci_mem_offset)
                        return 0;

                /* The BAR is 0, let's check if memory decoding is enabled on
                 * the bridge. If not, we consider it unassigned
                 */
                pci_read_config_word(dev, PCI_COMMAND, &command);
                if ((command & PCI_COMMAND_MEMORY) == 0)
                        return 1;

                /* Memory decoding is enabled and the BAR is 0. If any of the bridge
                 * resources covers that starting address (0 then it's good enough for
                 * us for memory
                 */
                for (i = 0; i < 3; i++) {
                        if ((hose->mem_resources[i].flags & IORESOURCE_MEM) &&
                            hose->mem_resources[i].start == hose->pci_mem_offset)
                                return 0;
                }

                /* Well, it starts at 0 and we know it will collide so we may as
                 * well consider it as unassigned. That covers the Apple case.
                 */
                return 1;
        } else {
                /* If the BAR is non-0, then we consider it assigned */
                offset = (unsigned long)hose->io_base_virt - _IO_BASE;
                if (((res->start - offset) & 0xfffffffful) != 0)
                        return 0;

                /* Here, we are a bit different than memory as typically IO space
                 * starting at low addresses -is- valid. What we do instead if that
                 * we consider as unassigned anything that doesn't have IO enabled
                 * in the PCI command register, and that's it.
                 */
                pci_read_config_word(dev, PCI_COMMAND, &command);
                if (command & PCI_COMMAND_IO)
                        return 0;

                /* It's starting at 0 and IO is disabled in the bridge, consider
                 * it unassigned
                 */
                return 1;
        }
}

/* Fixup resources of a PCI<->PCI bridge */
static void __devinit pcibios_fixup_bridge(struct pci_bus *bus)
{
        struct resource *res;
        int i;

        struct pci_dev *dev = bus->self;

        for (i = 0; i < PCI_BUS_NUM_RESOURCES; ++i) {
                if ((res = bus->resource[i]) == NULL)
                        continue;
                if (!res->flags)
                        continue;
                if (i >= 3 && bus->self->transparent)
                        continue;

                pr_debug("PCI:%s Bus rsrc %d %016llx-%016llx [%x] fixup...\n",
                         pci_name(dev), i,
                         (unsigned long long)res->start,\
                         (unsigned long long)res->end,
                         (unsigned int)res->flags);

                /* Perform fixup */
                fixup_resource(res, dev);

                /* Try to detect uninitialized P2P bridge resources,
                 * and clear them out so they get re-assigned later
                 */
                if (pcibios_uninitialized_bridge_resource(bus, res)) {
                        res->flags = 0;
                        pr_debug("PCI:%s            (unassigned)\n", pci_name(dev));
                } else {

                        pr_debug("PCI:%s            %016llx-%016llx\n",
                                 pci_name(dev),
                                 (unsigned long long)res->start,
                                 (unsigned long long)res->end);
                }
        }
}

static void __devinit __pcibios_fixup_bus(struct pci_bus *bus)
{
        struct pci_dev *dev = bus->self;

        pr_debug("PCI: Fixup bus %d (%s)\n", bus->number, dev ? pci_name(dev) : "PHB");

        /* Fixup PCI<->PCI bridges. Host bridges are handled separately, for
         * now differently between 32 and 64 bits.
         */
        if (dev != NULL)
                pcibios_fixup_bridge(bus);

        /* Additional setup that is different between 32 and 64 bits for now */
        pcibios_do_bus_setup(bus);

        /* Platform specific bus fixups */
        if (ppc_md.pcibios_fixup_bus)
                ppc_md.pcibios_fixup_bus(bus);

        /* Read default IRQs and fixup if necessary */
        list_for_each_entry(dev, &bus->devices, bus_list) {
                pci_read_irq_line(dev);
                if (ppc_md.pci_irq_fixup)
                        ppc_md.pci_irq_fixup(dev);
        }
}

void __devinit pcibios_fixup_bus(struct pci_bus *bus)
{
        /* When called from the generic PCI probe, read PCI<->PCI bridge
         * bases before proceeding
         */
        if (bus->self != NULL)
                pci_read_bridge_bases(bus);
        __pcibios_fixup_bus(bus);
}
EXPORT_SYMBOL(pcibios_fixup_bus);

/* When building a bus from the OF tree rather than probing, we need a
 * slightly different version of the fixup which doesn't read the
 * bridge bases using config space accesses
 */
void __devinit pcibios_fixup_of_probed_bus(struct pci_bus *bus)
{
        __pcibios_fixup_bus(bus);
}

static int skip_isa_ioresource_align(struct pci_dev *dev)
{
        if ((ppc_pci_flags & PPC_PCI_CAN_SKIP_ISA_ALIGN) &&
            !(dev->bus->bridge_ctl & PCI_BRIDGE_CTL_ISA))
                return 1;
        return 0;
}

/*
 * We need to avoid collisions with `mirrored' VGA ports
 * and other strange ISA hardware, so we always want the
 * addresses to be allocated in the 0x000-0x0ff region
 * modulo 0x400.
 *
 * Why? Because some silly external IO cards only decode
 * the low 10 bits of the IO address. The 0x00-0xff region
 * is reserved for motherboard devices that decode all 16
 * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
 * but we want to try to avoid allocating at 0x2900-0x2bff
 * which might have be mirrored at 0x0100-0x03ff..
 */
void pcibios_align_resource(void *data, struct resource *res,
                                resource_size_t size, resource_size_t align)
{
        struct pci_dev *dev = data;

        if (res->flags & IORESOURCE_IO) {
                resource_size_t start = res->start;

                if (skip_isa_ioresource_align(dev))
                        return;
                if (start & 0x300) {
                        start = (start + 0x3ff) & ~0x3ff;
                        res->start = start;
                }
        }
}
EXPORT_SYMBOL(pcibios_align_resource);

/*
 * Reparent resource children of pr that conflict with res
 * under res, and make res replace those children.
 */
static int __init reparent_resources(struct resource *parent,
                                     struct resource *res)
{
        struct resource *p, **pp;
        struct resource **firstpp = NULL;

        for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
                if (p->end < res->start)
                        continue;
                if (res->end < p->start)
                        break;
                if (p->start < res->start || p->end > res->end)
                        return -1;      /* not completely contained */
                if (firstpp == NULL)
                        firstpp = pp;
        }
        if (firstpp == NULL)
                return -1;      /* didn't find any conflicting entries? */
        res->parent = parent;
        res->child = *firstpp;
        res->sibling = *pp;
        *firstpp = res;
        *pp = NULL;
        for (p = res->child; p != NULL; p = p->sibling) {
                p->parent = res;
                DBG(KERN_INFO "PCI: reparented %s [%llx..%llx] under %s\n",
                    p->name,
                    (unsigned long long)p->start,
                    (unsigned long long)p->end, res->name);
        }
        return 0;
}

/*
 *  Handle resources of PCI devices.  If the world were perfect, we could
 *  just allocate all the resource regions and do nothing more.  It isn't.
 *  On the other hand, we cannot just re-allocate all devices, as it would
 *  require us to know lots of host bridge internals.  So we attempt to
 *  keep as much of the original configuration as possible, but tweak it
 *  when it's found to be wrong.
 *
 *  Known BIOS problems we have to work around:
 *      - I/O or memory regions not configured
 *      - regions configured, but not enabled in the command register
 *      - bogus I/O addresses above 64K used
 *      - expansion ROMs left enabled (this may sound harmless, but given
 *        the fact the PCI specs explicitly allow address decoders to be
 *        shared between expansion ROMs and other resource regions, it's
 *        at least dangerous)
 *
 *  Our solution:
 *      (1) Allocate resources for all buses behind PCI-to-PCI bridges.
 *          This gives us fixed barriers on where we can allocate.
 *      (2) Allocate resources for all enabled devices.  If there is
 *          a collision, just mark the resource as unallocated. Also
 *          disable expansion ROMs during this step.
 *      (3) Try to allocate resources for disabled devices.  If the
 *          resources were assigned correctly, everything goes well,
 *          if they weren't, they won't disturb allocation of other
 *          resources.
 *      (4) Assign new addresses to resources which were either
 *          not configured at all or misconfigured.  If explicitly
 *          requested by the user, configure expansion ROM address
 *          as well.
 */

static void __init pcibios_allocate_bus_resources(struct list_head *bus_list)
{
        struct pci_bus *bus;
        int i;
        struct resource *res, *pr;

        /* Depth-First Search on bus tree */
        list_for_each_entry(bus, bus_list, node) {
                for (i = 0; i < PCI_BUS_NUM_RESOURCES; ++i) {
                        if ((res = bus->resource[i]) == NULL || !res->flags
                            || res->start > res->end)
                                continue;
                        if (bus->parent == NULL)
                                pr = (res->flags & IORESOURCE_IO) ?
                                        &ioport_resource : &iomem_resource;
                        else {
                                /* Don't bother with non-root busses when
                                 * re-assigning all resources. We clear the
                                 * resource flags as if they were colliding
                                 * and as such ensure proper re-allocation
                                 * later.
                                 */
                                if (ppc_pci_flags & PPC_PCI_REASSIGN_ALL_RSRC)
                                        goto clear_resource;
                                pr = pci_find_parent_resource(bus->self, res);
                                if (pr == res) {
                                        /* this happens when the generic PCI
                                         * code (wrongly) decides that this
                                         * bridge is transparent  -- paulus
                                         */
                                        continue;
                                }
                        }

                        DBG("PCI: %s (bus %d) bridge rsrc %d: %016llx-%016llx "
                            "[0x%x], parent %p (%s)\n",
                            bus->self ? pci_name(bus->self) : "PHB",
                            bus->number, i,
                            (unsigned long long)res->start,
                            (unsigned long long)res->end,
                            (unsigned int)res->flags,
                            pr, (pr && pr->name) ? pr->name : "nil");

                        if (pr && !(pr->flags & IORESOURCE_UNSET)) {
                                if (request_resource(pr, res) == 0)
                                        continue;
                                /*
                                 * Must be a conflict with an existing entry.
                                 * Move that entry (or entries) under the
                                 * bridge resource and try again.
                                 */
                                if (reparent_resources(pr, res) == 0)
                                        continue;
                        }
                        printk(KERN_WARNING
                               "PCI: Cannot allocate resource region "
                               "%d of PCI bridge %d, will remap\n",
                               i, bus->number);
clear_resource:
                        res->flags = 0;
                }
                pcibios_allocate_bus_resources(&bus->children);
        }
}

static inline void __devinit alloc_resource(struct pci_dev *dev, int idx)
{
        struct resource *pr, *r = &dev->resource[idx];

        DBG("PCI: Allocating %s: Resource %d: %016llx..%016llx [%x]\n",
            pci_name(dev), idx,
            (unsigned long long)r->start,
            (unsigned long long)r->end,
            (unsigned int)r->flags);

        pr = pci_find_parent_resource(dev, r);
        if (!pr || (pr->flags & IORESOURCE_UNSET) ||
            request_resource(pr, r) < 0) {
                printk(KERN_WARNING "PCI: Cannot allocate resource region %d"
                       " of device %s, will remap\n", idx, pci_name(dev));
                if (pr)
                        DBG("PCI:  parent is %p: %016llx-%016llx [%x]\n", pr,
                            (unsigned long long)pr->start,
                            (unsigned long long)pr->end,
                            (unsigned int)pr->flags);
                /* We'll assign a new address later */
                r->flags |= IORESOURCE_UNSET;
                r->end -= r->start;
                r->start = 0;
        }
}

static void __init pcibios_allocate_resources(int pass)
{
        struct pci_dev *dev = NULL;
        int idx, disabled;
        u16 command;
        struct resource *r;

        for_each_pci_dev(dev) {
                pci_read_config_word(dev, PCI_COMMAND, &command);
                for (idx = 0; idx < 6; idx++) {
                        r = &dev->resource[idx];
                        if (r->parent)          /* Already allocated */
                                continue;
                        if (!r->flags || (r->flags & IORESOURCE_UNSET))
                                continue;       /* Not assigned at all */
                        if (r->flags & IORESOURCE_IO)
                                disabled = !(command & PCI_COMMAND_IO);
                        else
                                disabled = !(command & PCI_COMMAND_MEMORY);
                        if (pass == disabled)
                                alloc_resource(dev, idx);
                }
                if (pass)
                        continue;
                r = &dev->resource[PCI_ROM_RESOURCE];
                if (r->flags & IORESOURCE_ROM_ENABLE) {
                        /* Turn the ROM off, leave the resource region,
                         * but keep it unregistered.
                         */
                        u32 reg;
                        DBG("PCI: Switching off ROM of %s\n", pci_name(dev));
                        r->flags &= ~IORESOURCE_ROM_ENABLE;
                        pci_read_config_dword(dev, dev->rom_base_reg, &reg);
                        pci_write_config_dword(dev, dev->rom_base_reg,
                                               reg & ~PCI_ROM_ADDRESS_ENABLE);
                }
        }
}

void __init pcibios_resource_survey(void)
{
        /* Allocate and assign resources. If we re-assign everything, then
         * we skip the allocate phase
         */
        pcibios_allocate_bus_resources(&pci_root_buses);

        if (!(ppc_pci_flags & PPC_PCI_REASSIGN_ALL_RSRC)) {
                pcibios_allocate_resources(0);
                pcibios_allocate_resources(1);
        }

        if (!(ppc_pci_flags & PPC_PCI_PROBE_ONLY)) {
                DBG("PCI: Assigning unassigned resouces...\n");
                pci_assign_unassigned_resources();
        }

        /* Call machine dependent fixup */
        if (ppc_md.pcibios_fixup)
                ppc_md.pcibios_fixup();
}

#ifdef CONFIG_HOTPLUG
/* This is used by the pSeries hotplug driver to allocate resource
 * of newly plugged busses. We can try to consolidate with the
 * rest of the code later, for now, keep it as-is
 */
void __devinit pcibios_claim_one_bus(struct pci_bus *bus)
{
        struct pci_dev *dev;
        struct pci_bus *child_bus;

        list_for_each_entry(dev, &bus->devices, bus_list) {
                int i;

                for (i = 0; i < PCI_NUM_RESOURCES; i++) {
                        struct resource *r = &dev->resource[i];

                        if (r->parent || !r->start || !r->flags)
                                continue;
                        pci_claim_resource(dev, i);
                }
        }

        list_for_each_entry(child_bus, &bus->children, node)
                pcibios_claim_one_bus(child_bus);
}
EXPORT_SYMBOL_GPL(pcibios_claim_one_bus);
#endif /* CONFIG_HOTPLUG */

int pcibios_enable_device(struct pci_dev *dev, int mask)
{
        if (ppc_md.pcibios_enable_device_hook)
                if (ppc_md.pcibios_enable_device_hook(dev))
                        return -EINVAL;

        return pci_enable_resources(dev, mask);
}