[coreboot] Problem: 8254 timer not connected to IO-APIC.

Rudolf Marek r.marek at assembler.cz
Thu Jan 14 15:57:21 CET 2010


I think this message about the bug is related to wrong ACPI IRQ ovveride entries.

Usually there are two IRQ overrides. IRQ0 override means that IRQ0 is not 
connected to pin 0 on APIC but to another, most likely pin 2. Check the figure 
above why. Second IRQ override is for ACPI IRQ. This overrides the 'level' of 
the interrupt to 'active low'. The rest of the table is filled with NMI entries 
for the processor.

http://www.coreboot.org/File:ApicSystem.svg

Hope it helps,

Rudolf




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