[PATCH v3 0/6] Device tree support for Hyper-V VMBus driver

Saurabh Sengar
2023-02-06T17:54:35Z

This set of patches expands the VMBus driver to include device tree
support. This feature allows for a kernel boot without the use of ACPI
tables, resulting in a smaller memory footprint and potentially faster
boot times. This is tested by enabling CONFIG_FLAT and OF_EARLY_FLATTREE
for x86.

The first two patches enable compilation of Hyper-V APIs in a non-ACPI
build.

The third patch converts the VMBus driver from acpi to more generic
platform driver.

Further to add device tree documentation for VMBus, it needs to club with
other virtualization driver's documentation. For this rename the virtio
folder to more generic hypervisor, so that all the hypervisor based
devices can co-exist in a single place in device tree documentation. The
fourth patch does this renaming.

The fifth patch introduces the device tree documentation for VMBus.

The sixth patch adds device tree support to the VMBus driver. Currently
this is tested only for x86 and it may not work for other archs.

[V3]
- Changed the logic to use generic api (for_each_of_range) for parsing "ranges".
- Remove dependency of ACPI for HYPERV in case of x86.
- Removed "device tree bindings" from title and patch subject.
- Removed duplicate vendor prefix, used microsoft instead of msft.
- Use 'soc' in example of device tree documantation for parent node.
- Fixed compatible schemas error generated in other modules referring to
virtio.
- Drop hex notation and leading zeros from device tree cell properties.
- Added missing full stop at the end of commit message.
- Typos fix: s/Initaly/Initially/ and s/hibernate/hibernation/.
- Replace to_acpi_device with ACPI_COMPANION which simplify the logic.
- Added more info in cover letter aboutsystem under test.

[v2]
- Convert VMBus acpi device to platform device, and added device tree support
in separate patch. This enables using same driver structure for both the flows.
- In Device tree documentation, changed virtio folder to hypervisor and moved
VMBus documentation there.
- Moved bindings before Device tree patch.
- Removed stale ".data" and ".name" field from of_device match table.
- Removed debug print.

Saurabh Sengar (6):
drivers/clocksource/hyper-v: non ACPI support in hyperv clock
Drivers: hv: allow non ACPI compilation for
hv_is_hibernation_supported
Drivers: hv: vmbus: Convert acpi_device to more generic
platform_device
dt-bindings: hypervisor: Rename virtio to hypervisor
dt-bindings: hypervisor: VMBus
Driver: VMBus: Add device tree support

.../devicetree/bindings/gpio/gpio-virtio.yaml | 4 +-
.../bindings/hypervisor/microsoft,vmbus.yaml | 48 +++++++
.../bindings/{virtio => hypervisor}/mmio.yaml | 2 +-
.../{virtio => hypervisor}/pci-iommu.yaml | 2 +-
.../{virtio => hypervisor}/virtio-device.yaml | 2 +-
.../devicetree/bindings/i2c/i2c-virtio.yaml | 4 +-
MAINTAINERS | 3 +-
drivers/clocksource/hyperv_timer.c | 15 ++-
drivers/hv/Kconfig | 4 +-
drivers/hv/hv_common.c | 4 +
drivers/hv/vmbus_drv.c | 118 ++++++++++++++----
11 files changed, 169 insertions(+), 37 deletions(-)
create mode 100644 Documentation/devicetree/bindings/hypervisor/microsoft,vmbus.yaml
rename Documentation/devicetree/bindings/{virtio => hypervisor}/mmio.yaml (95%)
rename Documentation/devicetree/bindings/{virtio => hypervisor}/pci-iommu.yaml (98%)
rename Documentation/devicetree/bindings/{virtio => hypervisor}/virtio-device.yaml (93%)

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2.25.1