From be0e92568f115488e0555ec67a27a6b93d212a4e Mon Sep 17 00:00:00 2001 From: Aladyshev Konstantin Date: Tue, 18 Dec 2012 22:29:20 +0400 Subject: [PATCH] clear_ioapic: Fix reading of number of interrupts for IO-APICs Apply the same fix for `setup_ioapic` as done in the following commit. commit 23c046b6f16805ff0131460189967bf261d704de Author: Nico Huber Date: Mon Sep 24 10:48:43 2012 +0200 Fix reading of number of interrupts for IO-APICs The number read from the io-apic register represents the index of the highest interrupt redirection entry, i.e. the number of interrupts minus one. Change-Id: I54c992e4ff400de24bb9fef5d82251078f92c588 Signed-off-by: Nico Huber Reviewed-on: http://review.coreboot.org/1624 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer Change-Id: I7b730d016a514c95c3b32aee6f31bd3d7b2c08cb Signed-off-by: Aladyshev Konstantin Reviewed-on: http://review.coreboot.org/2043 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel Reviewed-by: Patrick Georgi --- src/arch/x86/lib/ioapic.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/src/arch/x86/lib/ioapic.c b/src/arch/x86/lib/ioapic.c index 018a42c173..e05d80c7a6 100644 --- a/src/arch/x86/lib/ioapic.c +++ b/src/arch/x86/lib/ioapic.c @@ -43,8 +43,11 @@ void clear_ioapic(u32 ioapic_base) /* Read the available number of interrupts. */ ioapic_interrupts = (io_apic_read(ioapic_base, 0x01) >> 16) & 0xff; - if (!ioapic_interrupts || ioapic_interrupts == 0xff) - ioapic_interrupts = 24; + if (ioapic_interrupts == 0xff) + ioapic_interrupts = 23; + ioapic_interrupts += 1; /* Bits 23-16 specify the maximum redirection + entry, which is the number of interrupts + minus 1. */ printk(BIOS_DEBUG, "IOAPIC: %d interrupts\n", ioapic_interrupts); low = DISABLED;