[SeaBIOS] system_powerdown not working for qemu-kvm 0.12.4?

Avi Kivity avi at redhat.com
Tue Oct 12 09:39:50 CEST 2010

  On 10/12/2010 09:33 AM, Avi Kivity wrote:
> Aha! The piix4 specification updates says:
>> • IRQ9OUT#/GPO29 should be labeled as IRQ9OUT/GPO29

Even more explicitly:

> 14. IRQ9OUT# Is Active HI
> Problem: The signal identified as IRQ9OUT#/GPO29, pin F3, is not 
> active level LO, it is active level HI, when APIC Chip Select 
> (XBCS[8]) is set.
> Implication: This signal is typically used in Dual Processor capable 
> systems and is connected to an IOAPIC. If the IOAPIC input is 
> programmed for level LO, and SCIs or SM Bus events in the 
> PIIX4/PIIX4E/PIIX4M are programmed to be reported on IRQ9OUT, devices 
> using these will not be recognized by the IOAPIC and will not work 
> correctly.
> Workaround: Program the appropriate input of the IOAPIC to active 
> level HI.
> Status: This will not be fixed in the PIIX4/PIIX4E/PIIX4M. This is 
> planned to be incorporated into the PIIX4 datasheet as a specification 
> change.

I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.

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