On Wed, 11 May 2016 11:19:25 -0400 "Kevin O'Connor" <kevin@xxxxxxxxxxxx> wrote: > On Tue, May 10, 2016 at 09:19:52AM -0600, Alex Williamson wrote: > > On Tue, 23 Feb 2016 10:22:33 -0500 > > "Kevin O'Connor" <kevin@xxxxxxxxxxxx> wrote: > > > > > On Tue, Feb 16, 2016 at 02:39:27PM -0700, 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 is a dummy file, it has no backing so we only > > > > allocate the space without copying anything into it. This space > > > > requires 1MB alignment and is generally either 1MB or 2MB, depending > > > > on the hardware config. If the user has opted in QEMU to expose > > > > additional stolen memory beyond the GTT (GGMS), the GMS may add an > > > > additional 32MB to 512MB. 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". > > > > > > Thanks. I'd be interested in seeing how the discussion with Michael > > > and Igor works out (wrt using a standardized interface for > > > communicating addresses between qemu and firmware) before adopting > > > this interface in SeaBIOS. > > > > Apologies if I missed it, but I haven't seen any work in this > > direction, please point me to it if I'm wrong. Now that QEMU 2.6 is > > wrapping up, I'd like to get IGD assignment support in for 2.7, but we > > can't do that without BIOS support. How shall we proceed? Thanks, > > If there's no consensus on standardizing the qemu/firmware interface > for addresses then I'm okay with the custom solution you last > proposed. So, I'd say submit your patches and if they are accepted in > QEMU then I will follow suit and apply them to SeaBIOS. Thanks Kevin, I'll post the proposed fw_cfg files as a separate RFC to QEMU to make sure they get eyes on them rather than just having them buried in a patch and we'll go from there. Thanks, Alex -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
