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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/pci/setup-irq.c
downloadlwn-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.c64
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);
+ }
+}