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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/pci/setup-irq.c | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/pci/setup-irq.c')
-rw-r--r-- | drivers/pci/setup-irq.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/drivers/pci/setup-irq.c b/drivers/pci/setup-irq.c new file mode 100644 index 000000000000..a251289c9958 --- /dev/null +++ b/drivers/pci/setup-irq.c @@ -0,0 +1,64 @@ +/* + * 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/init.h> +#include <linux/kernel.h> +#include <linux/pci.h> +#include <linux/errno.h> +#include <linux/ioport.h> +#include <linux/cache.h> + + +static void __init +pdev_fixup_irq(struct pci_dev *dev, + u8 (*swizzle)(struct pci_dev *, u8 *), + int (*map_irq)(struct pci_dev *, u8, u8)) +{ + u8 pin, slot; + int irq; + + /* 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 0 and illegal. */ + if (pin == 0 || pin > 4) + pin = 1; + + /* 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; + + pr_debug("PCI: fixup irq: (%s) got %d\n", + dev->dev.kobj.name, 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 __init +pci_fixup_irqs(u8 (*swizzle)(struct pci_dev *, u8 *), + int (*map_irq)(struct pci_dev *, u8, u8)) +{ + struct pci_dev *dev = NULL; + while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) { + pdev_fixup_irq(dev, swizzle, map_irq); + } +} |