Commit-ID: f395dcae7a68497751869cf0031fd8ce5e115f0a Gitweb: http://git.kernel.org/tip/f395dcae7a68497751869cf0031fd8ce5e115f0a Author: Jiang Liu <[email protected]> AuthorDate: Wed, 27 Aug 2014 13:53:11 +0800 Committer: Thomas Gleixner <[email protected]> CommitDate: Wed, 27 Aug 2014 11:02:16 +0200
x86: irq: Fix bug in setting IOAPIC pin attributes Commit 15a3c7cc9154321fc3 "x86, irq: Introduce two helper functions to support irqdomain map operation" breaks LPSS ACPI enumerated devices. On startup, IOAPIC driver preallocates IRQ descriptors and programs IOAPIC pins with default level and polarity attributes for all legacy IRQs. Later legacy IRQ users may fail to set IOAPIC pin attributes if the requested attributes conflicts with the default IOAPIC pin attributes. So change mp_irqdomain_map() to allow the first legacy IRQ user to reprogram IOAPIC pin with different attributes. Reported-and-tested-by: Mika Westerberg <[email protected]> Signed-off-by: Jiang Liu <[email protected]> Cc: Konrad Rzeszutek Wilk <[email protected]> Cc: Tony Luck <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Benjamin Herrenschmidt <[email protected]> Cc: Rafael J. Wysocki <[email protected]> Cc: Bjorn Helgaas <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Yinghai Lu <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Grant Likely <[email protected]> Cc: Prarit Bhargava <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]> --- arch/x86/kernel/apic/io_apic.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 29290f5..40a4aa3 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -1070,6 +1070,11 @@ static int mp_map_pin_to_irq(u32 gsi, int idx, int ioapic, int pin, } if (flags & IOAPIC_MAP_ALLOC) { + /* special handling for legacy IRQs */ + if (irq < nr_legacy_irqs() && info->count == 1 && + mp_irqdomain_map(domain, irq, pin) != 0) + irq = -1; + if (irq > 0) info->count++; else if (info->count == 0) @@ -3896,7 +3901,15 @@ int mp_irqdomain_map(struct irq_domain *domain, unsigned int virq, info->polarity = 1; } info->node = NUMA_NO_NODE; - info->set = 1; + + /* + * setup_IO_APIC_irqs() programs all legacy IRQs with default + * trigger and polarity attributes. Don't set the flag for that + * case so the first legacy IRQ user could reprogram the pin + * with real trigger and polarity attributes. + */ + if (virq >= nr_legacy_irqs() || info->count) + info->set = 1; } set_io_apic_irq_attr(&attr, ioapic, hwirq, info->trigger, info->polarity); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
