Hi vfio users and developpers,
I'm trying to GPU passthrough my core i5-1135G7
<https://ark.intel.com/content/www/us/en/ark/products/208658/intel-core-i51135g7-processor-8m-cache-up-to-4-20-ghz.html>
(Iris Xe) using vfio ( QEMU version 6.0.0 kernel 5.11)

I used my laptop BIOS file from which I extracted the efi IntelGopDriver
and vbt files (note that it seems to have two vbt in BIOS file), I used the
same one I found in "/sys/kernel/debug/dri/0/i915_vbt", then I recompiled
OVMF with this files using https://github.com/Kethen/edk2 project.

On my host I blacklisted i915 and related drivers, disable efi framebuffer
and load vfio at boot. I didn't try the legacy way as the 11th intel
generation no more support legacy boot.

Actually the linux guest run well as I can connect using serial or ssh but
it does not use screen (a "black light" change at VM boot).

I can see this error messages

pci 0000:06:02.0: can't claim BAR 6 [mem 0xffff8000-0xffffffff pref]:
no compatible bridge window
i915 0000:06:02.0: [drm] Failed to find VBIOS tables (VBT)
i915 0000:06:02.0: [drm] ERROR CPU pipe A FIFO underrun

from dmesg | grep "06:02"
[    0.210469] pci 0000:06:02.0: [8086:9a49] type 00 class 0x030000
[    0.215803] pci 0000:06:02.0: reg 0x10: [mem 0xc0000000-0xc0ffffff 64bit]
[    0.219769] pci 0000:06:02.0: reg 0x18: [mem
0x800000000-0x80fffffff 64bit pref]
[    0.223748] pci 0000:06:02.0: reg 0x20: [io  0x9080-0x90bf]
[    0.231948] pci 0000:06:02.0: reg 0x30: [mem 0xffff8000-0xffffffff pref]
[    0.231971] pci 0000:06:02.0: DMAR: Skip IOMMU disabling for graphics
[    0.268735] pci 0000:06:02.0: vgaarb: VGA device added:
decodes=io+mem,owns=none,locks=none
[    0.268735] pci 0000:06:02.0: vgaarb: bridge control possible
[    0.268735] pci 0000:06:02.0: vgaarb: setting as boot device (VGA
legacy resources not available)
[    0.356441] pci 0000:06:02.0: can't claim BAR 6 [mem
0xffff8000-0xffffffff pref]: no compatible bridge window
[    0.363647] pci 0000:06:02.0: BAR 6: assigned [mem
0xc1008000-0xc100ffff pref]
[    1.940762] i915 0000:06:02.0: vgaarb: deactivate vga console
[    2.022964] i915 0000:06:02.0: [drm] Failed to find VBIOS tables (VBT)
[    2.023670] i915 0000:06:02.0: vgaarb: changed VGA decodes:
olddecodes=io+mem,decodes=io+mem:owns=none
[    2.027066] i915 0000:06:02.0: [drm] Finished loading DMC firmware
i915/tgl_dmc_ver2_08.bin (v2.8)
[    2.392830] i915 0000:06:02.0: [drm] [ENCODER:307:DDI A/PHY A] is
disabled/in DSI mode with an ungated DDI clock, gate it
[    2.400635] [drm] Initialized i915 1.6.0 20201103 for 0000:06:02.0 on minor 0
[    2.410040] i915 0000:06:02.0: [drm] fb0: i915drmfb frame buffer device
[    2.717431] i915 0000:06:02.0: [drm] *ERROR* CPU pipe A FIFO underrun


I'm not sure I well compiled OVMF using my Vbt.bin when I see this message
"i915 0000:06:02.0: [drm] Failed to find VBIOS tables (VBT)"

I also wrote informations about my attempts here :
https://www.reddit.com/r/VFIO/comments/s726zt/tiger_lake_iris_xe_single_gpu_passthrough/

Will vfio support Iris Xe passthrough as Intel seems to support SR-IOV in
their newer GPU and
does qemu need to receive changes to support this use case ?

Thanks for your time and all the wonderful work you have already done on
VFIO !
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