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Subject[PATCH v2 3/4] dt-bindings: clock: Add device tree bindings for vmclock
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From: David Woodhouse <dwmw@amazon.co.uk>

Add device tree bindings for the vmclock device, similar to the existing
vmgenid bindings. The vmclock device provides a PTP clock source and
precise timekeeping across live migration and snapshot/restore operations.

The bindings specify a required memory region containing the vmclock_abi
structure and an optional interrupt for clock disruption notifications.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Babis Chalios <bchalios@amazon.es>
---
.../bindings/clock/amazon,vmclock.yaml | 46 +++++++++++++++++++
1 file changed, 46 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/amazon,vmclock.yaml

diff --git a/Documentation/devicetree/bindings/clock/amazon,vmclock.yaml b/Documentation/devicetree/bindings/clock/amazon,vmclock.yaml
new file mode 100644
index 000000000000..f7dfa022bf6f
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/amazon,vmclock.yaml
@@ -0,0 +1,46 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/amazon,vmclock.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Virtual Machine Clock
+
+maintainers:
+ - David Woodhouse <dwmw2@infradead.org>
+
+description:
+ The vmclock device provides a precise clock source and allows for
+ accurate timekeeping across live migration and snapshot/restore
+ operations. The full specification of the shared data structure
+ is available at https://david.woodhou.se/VMClock.pdf
+
+properties:
+ compatible:
+ const: amazon,vmclock
+
+ reg:
+ description:
+ Specifies the shared memory region containing the vmclock_abi structure.
+ maxItems: 1
+
+ interrupts:
+ description:
+ Interrupt used to notify when the contents of the vmclock_abi structure
+ have been updated.
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ vmclock@80000000 {
+ compatible = "amazon,vmclock";
+ reg = <0x80000000 0x1000>;
+ interrupts = <GIC_SPI 36 IRQ_TYPE_EDGE_RISING>;
+ };
--
2.34.1

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