From: "Edgar E. Iglesias" <[email protected]> This adds virtio-msg, a new virtio transport. Virtio-msg works by exchanging messages over a bus and doesn't rely on trapping and emulation making it a good fit for a number of applications such as AMP, real-time and safety applications.
Together with the new transport, this series adds a PCI device that implements an AMP setup much like it could look if two SoC's would use virtio-msg across a PCI link. Current gaps and limitations: Shared memory FIFO layout likely to change in the future. Temporarily uses PCI Vendor Xilinx / Device 0x9039. Documentation. The virtio-msg draft spec: https://github.com/Linaro/virtio-msg-spec/ QEMU with these patches: https://github.com/edgarigl/qemu/tree/edgar/virtio-msg-rfc Linux with virtio-msg support: https://github.com/edgarigl/linux/tree/edgari/virtio-msg-6.17 To try it, first build Linux with the following enabled: CONFIG_VIRTIO_MSG=y CONFIG_VIRTIO_MSG_AMP=y CONFIG_VIRTIO_MSG_AMP_PCI=y Boot linux on QEMU with a virtio-msg-amp-pci device, in this example with a virtio-net device attached to it: -device virtio-msg-amp-pci -device virtio-net-device,netdev=n0 -netdev user,id=n0 If you're running on a QEMU machine that has virtio-mmio enabled, e.g ARM virt, you'll need to specify the virtio-bus for the device, otherwise QEMU will connect it to virtio-mmio. For ARM virt machines: -device virtio-msg-amp-pci -device virtio-net-device,netdev=n0,bus=/gpex-pcihost/pcie.0/virtio-msg-amp-pci/fifo0/virtio-msg/bus0/virtio-msg-dev -netdev user,id=n0 Cheers, Edgar Edgar E. Iglesias (5): virtio: Introduce notify_queue virtio: Add virtio_queue_get_rings virtio: Add the virtio-msg transport hw/misc: Add generic virtio-msg AMP PCI device docs: Describe virtio-msg-amp-pci .../devices/virtio/virtio-msg-amp-pci.rst | 70 ++ hw/misc/Kconfig | 7 + hw/misc/meson.build | 1 + hw/misc/virtio-msg-amp-pci.c | 328 +++++++ hw/virtio/Kconfig | 4 + hw/virtio/meson.build | 5 + hw/virtio/virtio-msg-bus.c | 89 ++ hw/virtio/virtio-msg.c | 695 ++++++++++++++ hw/virtio/virtio.c | 23 + include/hw/virtio/spsc_queue.h | 213 +++++ include/hw/virtio/virtio-bus.h | 1 + include/hw/virtio/virtio-msg-bus.h | 95 ++ include/hw/virtio/virtio-msg-prot.h | 846 ++++++++++++++++++ include/hw/virtio/virtio-msg.h | 56 ++ include/hw/virtio/virtio.h | 2 + 15 files changed, 2435 insertions(+) create mode 100644 docs/system/devices/virtio/virtio-msg-amp-pci.rst create mode 100644 hw/misc/virtio-msg-amp-pci.c create mode 100644 hw/virtio/virtio-msg-bus.c create mode 100644 hw/virtio/virtio-msg.c create mode 100644 include/hw/virtio/spsc_queue.h create mode 100644 include/hw/virtio/virtio-msg-bus.h create mode 100644 include/hw/virtio/virtio-msg-prot.h create mode 100644 include/hw/virtio/virtio-msg.h -- 2.43.0
