alistair23-linux/drivers/pci/setup-irq.c
Ray Jui e6b29deafa PCI: Export symbols required for loadable host driver modules
Export the following symbols so they can be referenced by a PCI host bridge
driver compiled as a kernel loadable module:

  pci_common_swizzle
  pci_create_root_bus
  pci_stop_root_bus
  pci_remove_root_bus
  pci_assign_unassigned_bus_resources
  pci_fixup_irqs

Signed-off-by: Ray Jui <rjui@broadcom.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-04-08 14:17:10 -05:00

69 lines
1.8 KiB
C

/*
* drivers/pci/setup-irq.c
*
* Extruded from code written by
* Dave Rusling (david.rusling@reo.mts.dec.com)
* David Mosberger (davidm@cs.arizona.edu)
* David Miller (davem@redhat.com)
*
* Support routines for initializing a PCI subsystem.
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/cache.h>
void __weak pcibios_update_irq(struct pci_dev *dev, int irq)
{
dev_dbg(&dev->dev, "assigning IRQ %02d\n", irq);
pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
}
static void pdev_fixup_irq(struct pci_dev *dev,
u8 (*swizzle)(struct pci_dev *, u8 *),
int (*map_irq)(const struct pci_dev *, u8, u8))
{
u8 pin, slot;
int irq = 0;
/* If this device is not on the primary bus, we need to figure out
which interrupt pin it will come in on. We know which slot it
will come in on 'cos that slot is where the bridge is. Each
time the interrupt line passes through a PCI-PCI bridge we must
apply the swizzle function. */
pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
/* Cope with illegal. */
if (pin > 4)
pin = 1;
if (pin != 0) {
/* Follow the chain of bridges, swizzling as we go. */
slot = (*swizzle)(dev, &pin);
irq = (*map_irq)(dev, slot, pin);
if (irq == -1)
irq = 0;
}
dev->irq = irq;
dev_dbg(&dev->dev, "fixup irq: got %d\n", dev->irq);
/* Always tell the device, so the driver knows what is
the real IRQ to use; the device does not use it. */
pcibios_update_irq(dev, irq);
}
void pci_fixup_irqs(u8 (*swizzle)(struct pci_dev *, u8 *),
int (*map_irq)(const struct pci_dev *, u8, u8))
{
struct pci_dev *dev = NULL;
for_each_pci_dev(dev)
pdev_fixup_irq(dev, swizzle, map_irq);
}
EXPORT_SYMBOL_GPL(pci_fixup_irqs);