pci.c

优龙2410linux2.6.8内核源代码

{
	struct pci_controller *hose = (struct pci_controller *) bus->sysdata;
	unsigned long io_offset;
	struct resource *res;
	int i;

	io_offset = (unsigned long)hose->io_base_virt - isa_io_base;
	if (bus->parent == NULL) {
		/* This is a host bridge - fill in its resources */
		hose->bus = bus;

		bus->resource[0] = res = &hose->io_resource;
		if (!res->flags) {
			if (io_offset)
				printk(KERN_ERR "I/O resource not set for host"
				       " bridge %d\n", hose->index);
			res->start = 0;
			res->end = IO_SPACE_LIMIT;
			res->flags = IORESOURCE_IO;
		}
		res->start += io_offset;
		res->end += io_offset;

		for (i = 0; i < 3; ++i) {
			res = &hose->mem_resources[i];
			if (!res->flags) {
				if (i > 0)
					continue;
				printk(KERN_ERR "Memory resource not set for "
				       "host bridge %d\n", hose->index);
				res->start = hose->pci_mem_offset;
				res->end = ~0U;
				res->flags = IORESOURCE_MEM;
			}
			bus->resource[i+1] = res;
		}
	} else {
		/* This is a subordinate bridge */
		pci_read_bridge_bases(bus);

		for (i = 0; i < 4; ++i) {
			if ((res = bus->resource[i]) == NULL)
				continue;
			if (!res->flags)
				continue;
			if (io_offset && (res->flags & IORESOURCE_IO)) {
				res->start += io_offset;
				res->end += io_offset;
			} else if (hose->pci_mem_offset
				   && (res->flags & IORESOURCE_MEM)) {
				res->start += hose->pci_mem_offset;
				res->end += hose->pci_mem_offset;
			}
		}
	}

	if (ppc_md.pcibios_fixup_bus)
		ppc_md.pcibios_fixup_bus(bus);
}

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

/* the next one is stolen from the alpha port... */
void __init
pcibios_update_irq(struct pci_dev *dev, int irq)
{
	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
	/* XXX FIXME - update OF device tree node interrupt property */
}

int pcibios_enable_device(struct pci_dev *dev, int mask)
{
	u16 cmd, old_cmd;
	int idx;
	struct resource *r;

	if (ppc_md.pcibios_enable_device_hook)
		if (ppc_md.pcibios_enable_device_hook(dev, 0))
			return -EINVAL;
		
	pci_read_config_word(dev, PCI_COMMAND, &cmd);
	old_cmd = cmd;
	for (idx=0; idx<6; idx++) {
		r = &dev->resource[idx];
		if (r->flags & IORESOURCE_UNSET) {
			printk(KERN_ERR "PCI: Device %s not available because of resource collisions\n", pci_name(dev));
			return -EINVAL;
		}
		if (r->flags & IORESOURCE_IO)
			cmd |= PCI_COMMAND_IO;
		if (r->flags & IORESOURCE_MEM)
			cmd |= PCI_COMMAND_MEMORY;
	}
	if (cmd != old_cmd) {
		printk("PCI: Enabling device %s (%04x -> %04x)\n",
		       pci_name(dev), old_cmd, cmd);
		pci_write_config_word(dev, PCI_COMMAND, cmd);
	}
	return 0;
}

struct pci_controller*
pci_bus_to_hose(int bus)
{
	struct pci_controller* hose = hose_head;

	for (; hose; hose = hose->next)
		if (bus >= hose->first_busno && bus <= hose->last_busno)
			return hose;
	return NULL;
}

void*
pci_bus_io_base(unsigned int bus)
{
	struct pci_controller *hose;

	hose = pci_bus_to_hose(bus);
	if (!hose)
		return NULL;
	return hose->io_base_virt;
}

unsigned long
pci_bus_io_base_phys(unsigned int bus)
{
	struct pci_controller *hose;

	hose = pci_bus_to_hose(bus);
	if (!hose)
		return 0;
	return hose->io_base_phys;
}

unsigned long
pci_bus_mem_base_phys(unsigned int bus)
{
	struct pci_controller *hose;

	hose = pci_bus_to_hose(bus);
	if (!hose)
		return 0;
	return hose->pci_mem_offset;
}

unsigned long
pci_resource_to_bus(struct pci_dev *pdev, struct resource *res)
{
	/* Hack alert again ! See comments in chrp_pci.c
	 */
	struct pci_controller* hose =
		(struct pci_controller *)pdev->sysdata;
	if (hose && res->flags & IORESOURCE_MEM)
		return res->start - hose->pci_mem_offset;
	/* We may want to do something with IOs here... */
	return res->start;
}

/*
 * 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 __inline__ int
__pci_mmap_make_offset(struct pci_dev *dev, struct vm_area_struct *vma,
		       enum pci_mmap_state mmap_state)
{
	struct pci_controller *hose = (struct pci_controller *) dev->sysdata;
	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
	unsigned long size = vma->vm_end - vma->vm_start;
	unsigned long base;
	struct resource *res;
	int i;
	int ret = -EINVAL;

	if (hose == 0)
		return -EINVAL;		/* should never happen */
	if (offset + size <= offset)
		return -EINVAL;

	if (mmap_state == pci_mmap_mem) {
		/* PCI memory space */
		base = hose->pci_mem_offset;
		for (i = 0; i < 3; ++i) {
			res = &hose->mem_resources[i];
			if (res->flags == 0)
				continue;
			if (offset >= res->start - base
			    && offset + size - 1 <= res->end - base) {
				ret = 0;
				break;
			}
		}
		offset += hose->pci_mem_offset;
	} else {
		/* PCI I/O space */
		base = (unsigned long)hose->io_base_virt - isa_io_base;
		res = &hose->io_resource;
		if (offset >= res->start - base
		    && offset + size - 1 <= res->end - base)
			ret = 0;
		offset += hose->io_base_phys;
	}

	vma->vm_pgoff = offset >> PAGE_SHIFT;
	return ret;
}

/*
 * Set vm_flags of VMA, as appropriate for this architecture, for a pci device
 * mapping.
 */
static __inline__ void
__pci_mmap_set_flags(struct pci_dev *dev, struct vm_area_struct *vma,
		     enum pci_mmap_state mmap_state)
{
	vma->vm_flags |= VM_SHM | VM_LOCKED | VM_IO;
}

/*
 * Set vm_page_prot of VMA, as appropriate for this architecture, for a pci
 * device mapping.
 */
static __inline__ void
__pci_mmap_set_pgprot(struct pci_dev *dev, struct vm_area_struct *vma,
		      enum pci_mmap_state mmap_state, int write_combine)
{
	int prot = pgprot_val(vma->vm_page_prot);

	/* XXX would be nice to have a way to ask for write-through */
	prot |= _PAGE_NO_CACHE;
	if (!write_combine)
		prot |= _PAGE_GUARDED;
	vma->vm_page_prot = __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)
{
	int ret;

	ret = __pci_mmap_make_offset(dev, vma, mmap_state);
	if (ret < 0)
		return ret;

	__pci_mmap_set_flags(dev, vma, mmap_state);
	__pci_mmap_set_pgprot(dev, vma, mmap_state, write_combine);

	ret = remap_page_range(vma, vma->vm_start, vma->vm_pgoff << PAGE_SHIFT,
			       vma->vm_end - vma->vm_start, vma->vm_page_prot);

	return ret;
}

/* Obsolete functions. Should be removed once the symbios driver
 * is fixed
 */
unsigned long
phys_to_bus(unsigned long pa)
{
	struct pci_controller *hose;
	int i;

	for (hose = hose_head; hose; hose = hose->next) {
		for (i = 0; i < 3; ++i) {
			if (pa >= hose->mem_resources[i].start
			    && pa <= hose->mem_resources[i].end) {
				/*
				 * XXX the hose->pci_mem_offset really
				 * only applies to mem_resources[0].
				 * We need a way to store an offset for
				 * the others.  -- paulus
				 */
				if (i == 0)
					pa -= hose->pci_mem_offset;
				return pa;
			}
		}
	}
	/* hmmm, didn't find it */
	return 0;
}

unsigned long
pci_phys_to_bus(unsigned long pa, int busnr)
{
	struct pci_controller* hose = pci_bus_to_hose(busnr);
	if (!hose)
		return pa;
	return pa - hose->pci_mem_offset;
}

unsigned long
pci_bus_to_phys(unsigned int ba, int busnr)
{
	struct pci_controller* hose = pci_bus_to_hose(busnr);
	if (!hose)
		return ba;
	return ba + hose->pci_mem_offset;
}

/* Provide information on locations of various I/O regions in physical
 * memory.  Do this on a per-card basis so that we choose the right
 * root bridge.
 * Note that the returned IO or memory base is a physical address
 */

long sys_pciconfig_iobase(long which, unsigned long bus, unsigned long devfn)
{
	struct pci_controller* hose;
	long result = -EOPNOTSUPP;

	/* Argh ! Please forgive me for that hack, but that's the
	 * simplest way to get existing XFree to not lockup on some
	 * G5 machines... So when something asks for bus 0 io base
	 * (bus 0 is HT root), we return the AGP one instead.
	 */
#ifdef CONFIG_PPC_PMAC
	if (_machine == _MACH_Pmac && machine_is_compatible("MacRISC4"))
		if (bus == 0)
			bus = 0xf0;
#endif /* CONFIG_PPC_PMAC */

	hose = pci_bus_to_hose(bus);
	if (!hose)
		return -ENODEV;

	switch (which) {
	case IOBASE_BRIDGE_NUMBER:
		return (long)hose->first_busno;
	case IOBASE_MEMORY:
		return (long)hose->pci_mem_offset;
	case IOBASE_IO:
		return (long)hose->io_base_phys;
	case IOBASE_ISA_IO:
		return (long)isa_io_base;
	case IOBASE_ISA_MEM:
		return (long)isa_mem_base;
	}

	return result;
}

void __init
pci_init_resource(struct resource *res, unsigned long start, unsigned long end,
		  int flags, char *name)
{
	res->start = start;
	res->end = end;
	res->flags = flags;
	res->name = name;
	res->parent = NULL;
	res->sibling = NULL;
	res->child = NULL;
}

/*
 * Null PCI config access functions, for the case when we can't
 * find a hose.
 */
#define NULL_PCI_OP(rw, size, type)					\
static int								\
null_##rw##_config_##size(struct pci_dev *dev, int offset, type val)	\
{									\
	return PCIBIOS_DEVICE_NOT_FOUND;    				\
}

static int
null_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
		 int len, u32 *val)
{
	return PCIBIOS_DEVICE_NOT_FOUND;
}

static int
null_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
		  int len, u32 val)
{
	return PCIBIOS_DEVICE_NOT_FOUND;
}

static struct pci_ops null_pci_ops =
{
	null_read_config,
	null_write_config
};

/*
 * These functions are used early on before PCI scanning is done
 * and all of the pci_dev and pci_bus structures have been created.
 */
static struct pci_bus *
fake_pci_bus(struct pci_controller *hose, int busnr)
{
	static struct pci_bus bus;

	if (hose == 0) {
		hose = pci_bus_to_hose(busnr);
		if (hose == 0)
			printk(KERN_ERR "Can't find hose for PCI bus %d!\n", busnr);
	}
	bus.number = busnr;
	bus.sysdata = hose;
	bus.ops = hose? hose->ops: &null_pci_ops;
	return &bus;
}

#define EARLY_PCI_OP(rw, size, type)					\
int early_##rw##_config_##size(struct pci_controller *hose, int bus,	\
			       int devfn, int offset, type value)	\
{									\
	return pci_bus_##rw##_config_##size(fake_pci_bus(hose, bus),	\
					    devfn, offset, value);	\
}

EARLY_PCI_OP(read, byte, u8 *)
EARLY_PCI_OP(read, word, u16 *)
EARLY_PCI_OP(read, dword, u32 *)
EARLY_PCI_OP(write, byte, u8)
EARLY_PCI_OP(write, word, u16)
EARLY_PCI_OP(write, dword, u32)