ACPI/PCI: pci_link: penalize SCI correctly

Ondrej reported that IRQs stopped working in v4.7 on several
platforms.  A typical scenario, from Ondrej's VT82C694X/694X, is:

ACPI: Using PIC for interrupt routing
ACPI: PCI Interrupt Link [LNKA] (IRQs 1 3 4 5 6 7 10 *11 12 14 15)
ACPI: No IRQ available for PCI Interrupt Link [LNKA]
8139too 0000:00:0f.0: PCI INT A: no GSI

We're using PIC routing, so acpi_irq_balance == 0, and LNKA is already
active at IRQ 11. In that case, acpi_pci_link_allocate() only tries
to use the active IRQ (IRQ 11) which also happens to be the SCI.

We should penalize the SCI by PIRQ_PENALTY_PCI_USING, but
irq_get_trigger_type(11) returns something other than
IRQ_TYPE_LEVEL_LOW, so we penalize it by PIRQ_PENALTY_ISA_ALWAYS
instead, which makes acpi_pci_link_allocate() assume the IRQ isn't
available and give up.

Add acpi_penalize_sci_irq() so platforms can tell us the SCI IRQ,
trigger, and polarity directly and we don't have to depend on
irq_get_trigger_type().

Fixes: 103544d869 (ACPI,PCI,IRQ: reduce resource requirements)
Link: http://lkml.kernel.org/r/[email protected]
Reported-by: Ondrej Zary <[email protected]>
Acked-by: Bjorn Helgaas <[email protected]>
Signed-off-by: Sinan Kaya <[email protected]>
Tested-by: Jonathan Liu <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
This commit is contained in:
Sinan Kaya 2016-10-24 00:31:31 -04:00 • committed by Rafael J. Wysocki
commit f1caa61df2
3 changed files with 17 additions and 15 deletions

View file

@ -454,6 +454,7 @@ static void __init acpi_sci_ioapic_setup(u8 bus_irq, u16 polarity, u16 trigger,
polarity = acpi_sci_flags & ACPI_MADT_POLARITY_MASK;
mp_override_legacy_irq(bus_irq, polarity, trigger, gsi);
acpi_penalize_sci_irq(bus_irq, trigger, polarity);
/*
* stash over-ride to indicate we've been here