diff options
Diffstat (limited to 'drivers/acpi/pci_irq.c')
| -rw-r--r-- | drivers/acpi/pci_irq.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c index f907cfbfa13..7f9eba9a0b0 100644 --- a/drivers/acpi/pci_irq.c +++ b/drivers/acpi/pci_irq.c @@ -303,6 +303,61 @@ void acpi_pci_irq_del_prt(struct pci_bus *bus) /* -------------------------------------------------------------------------- PCI Interrupt Routing Support -------------------------------------------------------------------------- */ +#ifdef CONFIG_X86_IO_APIC +extern int noioapicquirk; +extern int noioapicreroute; + +static int bridge_has_boot_interrupt_variant(struct pci_bus *bus) +{ + struct pci_bus *bus_it; + + for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) { + if (!bus_it->self) + return 0; + if (bus_it->self->irq_reroute_variant) + return bus_it->self->irq_reroute_variant; + } + return 0; +} + +/* + * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ + * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does + * during interrupt handling). When this INTx generation cannot be disabled, + * we reroute these interrupts to their legacy equivalent to get rid of + * spurious interrupts. + */ +static int acpi_reroute_boot_interrupt(struct pci_dev *dev, + struct acpi_prt_entry *entry) +{ + if (noioapicquirk || noioapicreroute) { + return 0; + } else { + switch (bridge_has_boot_interrupt_variant(dev->bus)) { + case 0: + /* no rerouting necessary */ + return 0; + case INTEL_IRQ_REROUTE_VARIANT: + /* + * Remap according to INTx routing table in 6700PXH + * specs, intel order number 302628-002, section + * 2.15.2. Other chipsets (80332, ...) have the same + * mapping and are handled here as well. + */ + dev_info(&dev->dev, "PCI IRQ %d -> rerouted to legacy " + "IRQ %d\n", entry->index, + (entry->index % 4) + 16); + entry->index = (entry->index % 4) + 16; + return 1; + default: + dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy " + "IRQ: unknown mapping\n", entry->index); + return -1; + } + } +} +#endif /* CONFIG_X86_IO_APIC */ + static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin) { struct acpi_prt_entry *entry; @@ -311,6 +366,9 @@ static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin) entry = acpi_pci_irq_find_prt_entry(dev, pin); if (entry) { +#ifdef CONFIG_X86_IO_APIC + acpi_reroute_boot_interrupt(dev, entry); +#endif /* CONFIG_X86_IO_APIC */ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %s[%c] _PRT entry\n", pci_name(dev), pin_name(pin))); return entry; |