[Qemu-devel] [PATCH V3 0/3] hw/pcie: Multi-root support for Q35

[Marcel Apfelbaum <marcel@redhat.com>]

Note:
I took the liberty to CC all the reviewers that took their time
and had a look on the previous version, thanks!!

The PXB host bridge provides a way to have multiple PCI hierarchies (PCI root buses).
This series introduces the pxb-pcie counterpart for PCI Express machines(Currently Q35).

This approach works because the Root Complexes are exposed to guest as regular
(legacy) opaque PCI host bridges.

Tested on Fedora and Windows guests with both Root Ports and PCIe Switches.

v2 -> v3:
 Addressed Eduardo Habkost comments:
 - Added a bus property to PC machines and use it when querying bus 0.
 Addressed comments from multiple reviewers (Paolo,Markus,Gerd,Michael)
 - The issue was the backport compatibility when the PXB changes.
 - Following all the comments I chose:
   - Leave the PXB intact as it does the job and all its features
     (including the internal pci bridge) makes sense.
   - Add a new device that re-uses all the PXB code but is exposed as
     a different device to guests.
   - Once the functionality of the new device diverges we will have
     no problem to separate the code.

v1 -> v2:
 Addressed Gerd Hoffmann comments:
 - Added x-enable-internal-bridge compat property to keep the PCI
   bridge for older machine to avoid breaking migration.

Thanks,
Marcel

Marcel Apfelbaum (3):
  hw/acpi: merge pxb adjacent memory/IO ranges
  hw/pxb: introduce pxb-pcie expander for PCIe machines
  hw/i386: extend pxb query for all PC machines

 hw/i386/acpi-build.c                | 126 +++++++++++++++++++++---------------
 hw/i386/pc.c                        |   2 +-
 hw/i386/pc_piix.c                   |   1 +
 hw/i386/pc_q35.c                    |   1 +
 hw/pci-bridge/pci_expander_bridge.c |  98 +++++++++++++++++++++++-----
 include/hw/i386/pc.h                |   1 +
 include/hw/pci/pci.h                |   1 +
 7 files changed, 163 insertions(+), 67 deletions(-)

-- 
2.1.0