From 0d63b2dd31464cfccc80bbeedc24e3863fe4c895 Mon Sep 17 00:00:00 2001 From: Liu Ping Fan Date: Sun, 8 Dec 2013 17:38:16 +0800 Subject: [PATCH] hpet: inverse polarity when pin above ISA_NUM_IRQS According to hpet spec, hpet irq is high active. But according to ICH spec, there is inversion before the input of ioapic. So the OS will expect low active on this IRQ line. (On bare metal, if OS driver claims high active on this line, spurious irq is generated) We fold the emulation of this inversion inside the hpet logic. Signed-off-by: Liu Ping Fan Reviewed-by: Paolo Bonzini Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/timer/hpet.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c index 2eb75ea945..0aee2c1c41 100644 --- a/hw/timer/hpet.c +++ b/hw/timer/hpet.c @@ -198,13 +198,23 @@ static void update_irq(struct HPETTimer *timer, int set) if (!set || !timer_enabled(timer) || !hpet_enabled(timer->state)) { s->isr &= ~mask; if (!timer_fsb_route(timer)) { - qemu_irq_lower(s->irqs[route]); + /* fold the ICH PIRQ# pin's internal inversion logic into hpet */ + if (route >= ISA_NUM_IRQS) { + qemu_irq_raise(s->irqs[route]); + } else { + qemu_irq_lower(s->irqs[route]); + } } } else if (timer_fsb_route(timer)) { stl_le_phys(timer->fsb >> 32, timer->fsb & 0xffffffff); } else if (timer->config & HPET_TN_TYPE_LEVEL) { s->isr |= mask; - qemu_irq_raise(s->irqs[route]); + /* fold the ICH PIRQ# pin's internal inversion logic into hpet */ + if (route >= ISA_NUM_IRQS) { + qemu_irq_lower(s->irqs[route]); + } else { + qemu_irq_raise(s->irqs[route]); + } } else { s->isr &= ~mask; qemu_irq_pulse(s->irqs[route]);