Re: [Qemu-devel] [SeaBIOS] [PATCH v5] fw/pci: Add support for mapping Intel IGD via QEMU

[Gerd Hoffmann <kraxel@redhat.com>]

On Di, 2016-05-17 at 14:44 -0600, Alex Williamson wrote:
> QEMU provides two fw_cfg files to support IGD.  The first holds the
> OpRegion data which holds the Video BIOS Table (VBT).  This needs to
> be copied into reserved memory and the address stored in the ASL
> Storage register of the device at 0xFC offset in PCI config space.
> The OpRegion is generally 8KB.  This file is named "etc/igd-opregion".
> 
> The second file tells us the required size of the stolen memory space
> for the device.  This space requires 1MB alignment and is generally
> either 1MB to 8MB depending on hardware config, but may be hundreds of
> MB for user specified stolen memory.  The base address of the reserved
> memory allocated for this is written back to the Base Data of Stolen
> Memory register (BDSM) at PCI config offset 0x5C on the device.  This
> file is named "etc/igd-bdsm-size".
> 
> QEMU documents these fw_cfg entries in docs/igd-assign.txt.
> 
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
> ---
> 
> v6: fw_cfg BDSM entry now holds an 8-byte size integer as suggested
>     by Gerd.  Also renamed to etc/igd-bdsm-size.  Filter based on bdf
>     to only make use of this for the Intel VGA device at address
>     00:02.0, not that QEMU should attach this to anything else.
> 
> As always, comments appreciated.  I expect this will be on hold
> pending the QEMU support:
> 
> http://thread.gmane.org/gmane.comp.emulators.kvm.devel/152123

qemu patches are merged meanwhile.

Patch applied to master and cherry-picked into 1.9-stable.

thanks,
  Gerd