Re: [Qemu-devel] [PULL for-1.3 0/3] seabios: q35 update

[Gabriel L. Somlo]

On Tue, 04 Dec 2012 08:40:27 +0100 Gerd Hoffmann wrote:
>On Mon, 3 Dec 2012 13:47:04 -0500, Jason Baron wrote:
>> 2) HPET ACPI error
>> 
>> This line: 'IRQNoFlags () {2, 8}' in the HPET acpi table is causing the
>> folloing ACPI message (removing it makes it go away):
>
> Hmm.  That was added to make macos x happy and is also present on real
> hardware, so I'm wondering what is going on here.

Without that line, OS X only works as a single-core, non-SMP guest.
This is the "legacy replacement irq mapping" option for HPET (section
2.4.2, page 24 of the IA-PC HPET Specification).

The options are 'IRQNoFlags () {2, 8}' for "APIC mapping" or
'IRQNoFlags () {0, 8}' for "8259 mapping". Either one works for SMP + OS X.

I don't have an XP install image anymore, but does replacing 2,8 with
0,8 help ?

On a few of my machines, this is actually coded as

                        IRQNoFlags ()
                            {0}                 /* or 2 */
                        IRQNoFlags ()
                            {8}

Based on my reading of the ACPI manual, this should be syntactically
equivalent to the the comma-separated single-line format we're currently
using, but could it be that WinXP is picky about the specifics ?

Also, as far as I can tell, this change never made it into the
"q35-acpi-dsdt.dsl" file, just the "classic" acpi-dsdt.dsl (or, lately,
acpi-dsdt-hpet.dsl). I was about to submit another patch for that, but
now I guess I won't press it until we sort this out :)

--Gabriel