[Qemu-devel] [PATCH v2 00/10] igd passthrough chipset tweaks

[Gerd Hoffmann]

  Hi,

We have some code in our tree to support pci passthrough of intel
graphics devices (igd) on xen, which requires some chipset tweaks
for (a) the host bridge and (b) the lpc/isa-bridge to meat the
expectations of the guest driver.

For kvm we need pretty much the same, also the requirements for vgpu
(xengt/kvmgt) are very simliar.  This patch wires up the existing
support for kvm.  It also brings a bunch of bugfixes and cleanups.

Unfortunaly the oldish laptop I had planned to use for testing turned
out to have no working iommu support for igd, so this patch series
still has seen very light testing only.  Any testing feedback is very
welcome.

Testing with kvm/i440fx:
  Add '-M pc,igd-passthru=on -device igd-passthrough-isa-bridge,addr=1f'
  to turn on the chipset tweaks.  Passthrough the igd using vfio.

Testing with kvm/q35:
  Add '-M q35,igd-passthru=on' to turn on the the chipset tweaks.  Pick
  up the linux kernel patch referenced in patch #10, build a custom
  kernel with it.  Passthrough the igd using vfio.

Testing with xen:
  Existing setups should continue working ;)

Changes in v2:
  * Added igd-passthrough-isa-bridge support form kvm.
  * Added patch to drop has_igd_gfx_passthru.

TODO:
  * Possibly handle igd-passthrough-isa-bridge automatically (see patch 10).
  * Figure a way to handle the opregion, probably via vfio extension.
    Beyond the scope of this patch series, but probably needed to make
    laptop panels work correctly.

Gerd Hoffmann (10):
  pc: wire up TYPE_IGD_PASSTHROUGH_I440FX_PCI_DEVICE for !xen
  pc: remove has_igd_gfx_passthru global
  pc: move igd support code to igd.c
  igd: switch TYPE_IGD_PASSTHROUGH_I440FX_PCI_DEVICE to realize
  igd: TYPE_IGD_PASSTHROUGH_I440FX_PCI_DEVICE: call parent realize
  igd: use defines for standard pci config space offsets
  igd: revamp host config read
  igd: add q35 support
  igd: move igd-passthrough-isa-bridge to igd.c too
  igd: handle igd-passthrough-isa-bridge setup in realize()

 hw/i386/pc_piix.c         | 124 ++-----------------------------
 hw/pci-host/Makefile.objs |   3 +
 hw/pci-host/igd.c         | 181 ++++++++++++++++++++++++++++++++++++++++++++++
 hw/pci-host/piix.c        |  88 ----------------------
 hw/pci-host/q35.c         |   6 +-
 hw/xen/xen_pt.h           |   3 +-
 vl.c                      |  10 ---
 7 files changed, 195 insertions(+), 220 deletions(-)
 create mode 100644 hw/pci-host/igd.c

-- 
1.8.3.1