Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * drivers/pci/setup-irq.c |
| 3 | * |
| 4 | * Extruded from code written by |
| 5 | * Dave Rusling (david.rusling@reo.mts.dec.com) |
| 6 | * David Mosberger (davidm@cs.arizona.edu) |
| 7 | * David Miller (davem@redhat.com) |
| 8 | * |
| 9 | * Support routines for initializing a PCI subsystem. |
| 10 | */ |
| 11 | |
| 12 | |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/pci.h> |
| 16 | #include <linux/errno.h> |
| 17 | #include <linux/ioport.h> |
| 18 | #include <linux/cache.h> |
| 19 | |
| 20 | |
| 21 | static void __init |
| 22 | pdev_fixup_irq(struct pci_dev *dev, |
| 23 | u8 (*swizzle)(struct pci_dev *, u8 *), |
Ralf Baechle | d534194 | 2011-06-10 15:30:21 +0100 | [diff] [blame^] | 24 | int (*map_irq)(const struct pci_dev *, u8, u8)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | { |
| 26 | u8 pin, slot; |
Andreas Block | 691cd0c | 2007-02-05 16:36:07 -0800 | [diff] [blame] | 27 | int irq = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | |
| 29 | /* If this device is not on the primary bus, we need to figure out |
| 30 | which interrupt pin it will come in on. We know which slot it |
| 31 | will come in on 'cos that slot is where the bridge is. Each |
| 32 | time the interrupt line passes through a PCI-PCI bridge we must |
| 33 | apply the swizzle function. */ |
| 34 | |
| 35 | pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin); |
Andreas Block | 691cd0c | 2007-02-05 16:36:07 -0800 | [diff] [blame] | 36 | /* Cope with illegal. */ |
| 37 | if (pin > 4) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | pin = 1; |
| 39 | |
Andreas Block | 691cd0c | 2007-02-05 16:36:07 -0800 | [diff] [blame] | 40 | if (pin != 0) { |
| 41 | /* Follow the chain of bridges, swizzling as we go. */ |
| 42 | slot = (*swizzle)(dev, &pin); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | |
Andreas Block | 691cd0c | 2007-02-05 16:36:07 -0800 | [diff] [blame] | 44 | irq = (*map_irq)(dev, slot, pin); |
| 45 | if (irq == -1) |
| 46 | irq = 0; |
| 47 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | dev->irq = irq; |
| 49 | |
Bjorn Helgaas | 80ccba1 | 2008-06-13 10:52:11 -0600 | [diff] [blame] | 50 | dev_dbg(&dev->dev, "fixup irq: got %d\n", dev->irq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | |
| 52 | /* Always tell the device, so the driver knows what is |
| 53 | the real IRQ to use; the device does not use it. */ |
| 54 | pcibios_update_irq(dev, irq); |
| 55 | } |
| 56 | |
| 57 | void __init |
| 58 | pci_fixup_irqs(u8 (*swizzle)(struct pci_dev *, u8 *), |
Ralf Baechle | d534194 | 2011-06-10 15:30:21 +0100 | [diff] [blame^] | 59 | int (*map_irq)(const struct pci_dev *, u8, u8)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | { |
| 61 | struct pci_dev *dev = NULL; |
Kulikov Vasiliy | 4e344b1 | 2010-07-03 20:04:39 +0400 | [diff] [blame] | 62 | for_each_pci_dev(dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | pdev_fixup_irq(dev, swizzle, map_irq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | } |