[SeaBIOS] [PATCH v2 9/9] seabios: Build the dsdt separately

[Paolo Bonzini]

Il 10/10/2012 09:14, Gerd Hoffmann ha scritto:
>   Hi,
> 
>> Instead of moving just the dsdt to qemu, though, can we move all acpi
>> tables into qemu?  Moving just the dsdt can lead to conflicts with the
>> generated ssdt code and potentially some of the other acpi tables.
> 
> For now the plan is to keep the dsdt in the seabios git repo, but
> install them next to bios.bin, then have qemu pick the correct one
> depending on the machine type.
> 
>> The only seabios acpi dependency that pops into mind is the memory
>> addresses of the acpi tables themselves.
> 
> There is also the BDAT in the SSDT and the patching logic ...

The patching logic can be moved to QEMU with no problems.  The BDAT
perhaps could be replaced with a Package and Index().

I think there's no urgency to move ACPI tables to QEMU, but it would be
a useful cleanup if somebody has the time to do it.  It would improve
the degree to which compatibility machine types can mimic old versions
of QEMU, too.

The important thing is that it can be done incrementally.  Even the SSDT
can be split in multiple tables, one built by QEMU and one built by SeaBIOS.

Laszlo has been forward-porting some SeaBIOS changes to TianoCore.  When
he gets to the remaining bells-and-whistles (mostly hotplug and S3/S4),
perhaps he could instead add the fwcfg interface to TianoCore and move
them from SeaBIOS to QEMU.  IIUC it's just a sequence of

   uint16_t len;
   uint8_t  table[];

structs, it shouldn't take long to add it.

Paolo