Patrick Georgi (patrick@georgi-clan.de) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/1624
-gerrit
commit 91f016fb77ca94e50ecb6723035bf29b1547aaf8 Author: Nico Huber nico.huber@secunet.com 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 nico.huber@secunet.com --- 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 57b99e2..018a42c 100644 --- a/src/arch/x86/lib/ioapic.c +++ b/src/arch/x86/lib/ioapic.c @@ -85,8 +85,11 @@ void setup_ioapic(u32 ioapic_base, u8 ioapic_id)
/* 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);
#if CONFIG_IOAPIC_INTERRUPTS_ON_FSB