pci.c

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		size = GET_64BIT(ranges, 6);
		if (flags == 0 || size == 0)
			continue;
		if (flags & IORESOURCE_IO) {
			res = bus->resource[0];
			if (res->flags) {
				printk(KERN_ERR "PCI: ignoring extra I/O range"
				       " for bridge %s\n", node->full_name);
				continue;
			}
		} else {
			if (i >= PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES) {
				printk(KERN_ERR "PCI: too many memory ranges"
				       " for bridge %s\n", node->full_name);
				continue;
			}
			res = bus->resource[i];
			++i;
		}
		res->start = GET_64BIT(ranges, 1);
		res->end = res->start + size - 1;
		res->flags = flags;
		fixup_resource(res, dev);
	}
	sprintf(bus->name, "PCI Bus %04x:%02x", pci_domain_nr(bus),
		bus->number);

	mode = PCI_PROBE_NORMAL;
	if (ppc_md.pci_probe_mode)
		mode = ppc_md.pci_probe_mode(bus);
	if (mode == PCI_PROBE_DEVTREE)
		of_scan_bus(node, bus);
	else if (mode == PCI_PROBE_NORMAL)
		pci_scan_child_bus(bus);
}
#endif /* CONFIG_PPC_MULTIPLATFORM */

static void __devinit scan_phb(struct pci_controller *hose)
{
	struct pci_bus *bus;
	struct device_node *node = hose->arch_data;
	int i, mode;
	struct resource *res;

	bus = pci_create_bus(NULL, hose->first_busno, hose->ops, node);
	if (bus == NULL) {
		printk(KERN_ERR "Failed to create bus for PCI domain %04x\n",
		       hose->global_number);
		return;
	}
	bus->secondary = hose->first_busno;
	hose->bus = bus;

	bus->resource[0] = res = &hose->io_resource;
	if (res->flags && request_resource(&ioport_resource, res))
		printk(KERN_ERR "Failed to request PCI IO region "
		       "on PCI domain %04x\n", hose->global_number);

	for (i = 0; i < 3; ++i) {
		res = &hose->mem_resources[i];
		bus->resource[i+1] = res;
		if (res->flags && request_resource(&iomem_resource, res))
			printk(KERN_ERR "Failed to request PCI memory region "
			       "on PCI domain %04x\n", hose->global_number);
	}

	mode = PCI_PROBE_NORMAL;
#ifdef CONFIG_PPC_MULTIPLATFORM
	if (ppc_md.pci_probe_mode)
		mode = ppc_md.pci_probe_mode(bus);
	if (mode == PCI_PROBE_DEVTREE) {
		bus->subordinate = hose->last_busno;
		of_scan_bus(node, bus);
	}
#endif /* CONFIG_PPC_MULTIPLATFORM */
	if (mode == PCI_PROBE_NORMAL)
		hose->last_busno = bus->subordinate = pci_scan_child_bus(bus);
	pci_bus_add_devices(bus);
}

static int __init pcibios_init(void)
{
	struct pci_controller *hose, *tmp;

	/* For now, override phys_mem_access_prot. If we need it,
	 * later, we may move that initialization to each ppc_md
	 */
	ppc_md.phys_mem_access_prot = pci_phys_mem_access_prot;

#ifdef CONFIG_PPC_ISERIES
	iSeries_pcibios_init(); 
#endif

	printk("PCI: Probing PCI hardware\n");

	/* Scan all of the recorded PCI controllers.  */
	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
		scan_phb(hose);

#ifndef CONFIG_PPC_ISERIES
	if (pci_probe_only)
		pcibios_claim_of_setup();
	else
		/* FIXME: `else' will be removed when
		   pci_assign_unassigned_resources() is able to work
		   correctly with [partially] allocated PCI tree. */
		pci_assign_unassigned_resources();
#endif /* !CONFIG_PPC_ISERIES */

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

	/* Cache the location of the ISA bridge (if we have one) */
	ppc64_isabridge_dev = pci_get_class(PCI_CLASS_BRIDGE_ISA << 8, NULL);
	if (ppc64_isabridge_dev != NULL)
		printk("ISA bridge at %s\n", pci_name(ppc64_isabridge_dev));

	printk("PCI: Probing PCI hardware done\n");

	return 0;
}

subsys_initcall(pcibios_init);

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

int pcibios_enable_device(struct pci_dev *dev, int mask)
{
	u16 cmd, oldcmd;
	int i;

	pci_read_config_word(dev, PCI_COMMAND, &cmd);
	oldcmd = cmd;

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

		/* Only set up the requested stuff */
		if (!(mask & (1<<i)))
			continue;

		if (res->flags & IORESOURCE_IO)
			cmd |= PCI_COMMAND_IO;
		if (res->flags & IORESOURCE_MEM)
			cmd |= PCI_COMMAND_MEMORY;
	}

	if (cmd != oldcmd) {
		printk(KERN_DEBUG "PCI: Enabling device: (%s), cmd %x\n",
		       pci_name(dev), cmd);
                /* Enable the appropriate bits in the PCI command register.  */
		pci_write_config_word(dev, PCI_COMMAND, cmd);
	}
	return 0;
}

/*
 * Return the domain number for this bus.
 */
int pci_domain_nr(struct pci_bus *bus)
{
#ifdef CONFIG_PPC_ISERIES
	return 0;
#else
	struct pci_controller *hose = pci_bus_to_host(bus);

	return hose->global_number;
#endif
}

EXPORT_SYMBOL(pci_domain_nr);

/* Decide whether to display the domain number in /proc */
int pci_proc_domain(struct pci_bus *bus)
{
#ifdef CONFIG_PPC_ISERIES
	return 0;
#else
	struct pci_controller *hose = pci_bus_to_host(bus);
	return hose->buid;
#endif
}

/*
 * 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,
					       unsigned long *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) {
		*offset += hose->pci_mem_offset;
		res_bit = IORESOURCE_MEM;
	} else {
		io_offset = (unsigned long)hose->io_base_virt - pci_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;

	printk("PCI map for %s:%lx, prot: %lx\n", pci_name(dev), rp->start,
	       prot);

	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 offset,
				  unsigned long size,
				  pgprot_t protection)
{
	struct pci_dev *pdev = NULL;
	struct resource *found = NULL;
	unsigned long prot = pgprot_val(protection);
	int i;

	if (page_is_ram(offset >> PAGE_SHIFT))
		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)
{
	unsigned long offset = 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_flags |= VM_SHM | VM_LOCKED | VM_IO;
	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;
}

#ifdef CONFIG_PPC_MULTIPLATFORM
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_MULTIPLATFORM */

void pcibios_add_platform_entries(struct pci_dev *pdev)
{
#ifdef CONFIG_PPC_MULTIPLATFORM
	device_create_file(&pdev->dev, &dev_attr_devspec);
#endif /* CONFIG_PPC_MULTIPLATFORM */
}

#ifdef CONFIG_PPC_MULTIPLATFORM

#define ISA_SPACE_MASK 0x1
#define ISA_SPACE_IO 0x1

static void __devinit pci_process_ISA_OF_ranges(struct device_node *isa_node,
				      unsigned long phb_io_base_phys,
				      void __iomem * phb_io_base_virt)
{
	struct isa_range *range;
	unsigned long pci_addr;
	unsigned int isa_addr;
	unsigned int size;
	int rlen = 0;

	range = (struct isa_range *) get_property(isa_node, "ranges", &rlen);
	if (range == NULL || (rlen < sizeof(struct isa_range))) {
		printk(KERN_ERR "no ISA ranges or unexpected isa range size,"
		       "mapping 64k\n");
		__ioremap_explicit(phb_io_base_phys,
				   (unsigned long)phb_io_base_virt,
				   0x10000, _PAGE_NO_CACHE | _PAGE_GUARDED);
		return;	
	}
	
	/* From "ISA Binding to 1275"
	 * The ranges property is laid out as an array of elements,
	 * each of which comprises:
	 *   cells 0 - 1:	an ISA address
	 *   cells 2 - 4:	a PCI address 
	 *			(size depending on dev->n_addr_cells)
	 *   cell 5:		the size of the range
	 */
	if ((range->isa_addr.a_hi && ISA_SPACE_MASK) == ISA_SPACE_IO) {
		isa_addr = range->isa_addr.a_lo;