[Qemu-devel] [PATCH 0/6] AMD XGBE KVM platform passthrough

[Eric Auger <eric.auger@linaro.org>]

This series allows to set up AMD XGBE passthrough. This was tested on AMD
Seattle.

The first upstreamed device supporting KVM platform passthrough was the
Calxeda Midway XGMAC. Compared to this latter, the XGBE XGMAC exposes a
much more complex device tree node.

- First There are 2 device tree node formats:
one where XGBE and PHY are described in separate nodes and another one
that combines both description in a single node (only supported by 4.2
onwards kernels). Only the combined description is supported for passthrough,
meaning the host must be >= 4.2 and must feature a device tree with a combined
description. The guest will also be exposed with a combined description,
meaning only >= 4.2 guest are supported. It is not planned to support
separate node representation since assignment of the PHY is less
straigtforward.

- the XGMAC/PHY node depends on 2 clock nodes (DMA and PTP).
The code checks those clocks are fixed to make sure they cannot be
switched off at some point after the native driver gets unbound.

- there are many property values to populate on guest side. Most of them
cannot be hardcoded. That series implements host device tree blob extraction
from the host /sys/firmware/devicetree/base (inspired from dtc implementation)
and retrieve host property values to populate guest dtb.

- the case where the host uses ACPI is not yet covered since there is
  no usable ACPI description for this HW yet.

The patches can be found at
https://git.linaro.org/people/eric.auger/qemu.git/shortlog/refs/heads/v2.5.0-xgbe-v1

HISTORY:
RFC -> v1:
- no dependency anymore on dtc binary: load_device_tree_from_sysfs is
  self-contained and implements something similar to dtc read_fstree.
- take into account Alex' comments
- remove qemu_fdt_getprop_optional and use error API instead

Best Regards

Eric


Eric Auger (6):
  hw/vfio/platform: amd-xgbe device
  device_tree: introduce load_device_tree_from_sysfs
  device_tree: introduce qemu_fdt_node_path
  device_tree: qemu_fdt_getprop converted to use the error API
  hw/arm/sysbus-fdt: helpers for clock node generation
  hw/arm/sysbus-fdt: enable amd-xgbe dynamic instantiation

 device_tree.c                   | 158 +++++++++++++++++++++-
 hw/arm/sysbus-fdt.c             | 283 ++++++++++++++++++++++++++++++++++++++++
 hw/vfio/Makefile.objs           |   1 +
 hw/vfio/amd-xgbe.c              |  55 ++++++++
 include/hw/vfio/vfio-amd-xgbe.h |  51 ++++++++
 include/sysemu/device_tree.h    |   7 +-
 6 files changed, 549 insertions(+), 6 deletions(-)
 create mode 100644 hw/vfio/amd-xgbe.c
 create mode 100644 include/hw/vfio/vfio-amd-xgbe.h

-- 
1.9.1