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-rw-r--r--Documentation/devicetree/bindings/timestamp/hardware-timestamps-common.yaml29
-rw-r--r--Documentation/devicetree/bindings/timestamp/hte-consumer.yaml39
-rw-r--r--Documentation/devicetree/bindings/timestamp/nvidia,tegra194-hte.yaml88
3 files changed, 156 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/timestamp/hardware-timestamps-common.yaml b/Documentation/devicetree/bindings/timestamp/hardware-timestamps-common.yaml
new file mode 100644
index 000000000..fd6a7b51f
--- /dev/null
+++ b/Documentation/devicetree/bindings/timestamp/hardware-timestamps-common.yaml
@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timestamp/hardware-timestamps-common.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Hardware timestamp providers
+
+maintainers:
+ - Dipen Patel <dipenp@nvidia.com>
+
+description:
+ Some devices/SoCs have hardware timestamp engines (HTE) which can use
+ hardware means to timestamp entity in realtime. The entity could be anything
+ from GPIOs, IRQs, Bus and so on. The hardware timestamp engine present
+ itself as a provider with the bindings described in this document.
+
+properties:
+ $nodename:
+ pattern: "^timestamp(@.*|-[0-9a-f])?$"
+
+ "#timestamp-cells":
+ description:
+ Number of cells in a HTE specifier.
+
+required:
+ - "#timestamp-cells"
+
+additionalProperties: true
diff --git a/Documentation/devicetree/bindings/timestamp/hte-consumer.yaml b/Documentation/devicetree/bindings/timestamp/hte-consumer.yaml
new file mode 100644
index 000000000..5142d6d4f
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+++ b/Documentation/devicetree/bindings/timestamp/hte-consumer.yaml
@@ -0,0 +1,39 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timestamp/hte-consumer.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: HTE Consumer
+
+maintainers:
+ - Dipen Patel <dipenp@nvidia.com>
+
+select: true
+
+properties:
+ timestamps:
+ $ref: /schemas/types.yaml#/definitions/phandle-array
+ description:
+ The list of HTE provider phandle. The first cell must represent the
+ provider phandle followed by the line identifiers. The meaning of the
+ line identifier and exact number of arguments must be specified in the
+ HTE provider device tree binding document.
+
+ timestamp-names:
+ $ref: /schemas/types.yaml#/definitions/string-array
+ description:
+ An optional string property to label each line specifier present in the
+ timestamp property.
+
+dependencies:
+ timestamp-names: [ timestamps ]
+
+additionalProperties: true
+
+examples:
+ - |
+ hte_tegra_consumer {
+ timestamps = <&tegra_hte_aon 0x9>, <&tegra_hte_lic 0x19>;
+ timestamp-names = "hte-gpio", "hte-i2c";
+ };
diff --git a/Documentation/devicetree/bindings/timestamp/nvidia,tegra194-hte.yaml b/Documentation/devicetree/bindings/timestamp/nvidia,tegra194-hte.yaml
new file mode 100644
index 000000000..c31e207d1
--- /dev/null
+++ b/Documentation/devicetree/bindings/timestamp/nvidia,tegra194-hte.yaml
@@ -0,0 +1,88 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timestamp/nvidia,tegra194-hte.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Tegra194 on chip generic hardware timestamping engine (HTE)
+
+maintainers:
+ - Dipen Patel <dipenp@nvidia.com>
+
+description:
+ Tegra SoC has two instances of generic hardware timestamping engines (GTE)
+ known as GTE GPIO and GTE IRQ, which can monitor subset of GPIO and on chip
+ IRQ lines for the state change respectively, upon detection it will record
+ timestamp (taken from system counter) in its internal hardware FIFO. It has
+ a bitmap array arranged in 32bit slices where each bit represent signal/line
+ to enable or disable for the hardware timestamping. The GTE GPIO monitors
+ GPIO lines from the AON (always on) GPIO controller.
+
+properties:
+ compatible:
+ enum:
+ - nvidia,tegra194-gte-aon
+ - nvidia,tegra194-gte-lic
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ nvidia,int-threshold:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ HTE device generates its interrupt based on this u32 FIFO threshold
+ value. The recommended value is 1.
+ minimum: 1
+ maximum: 256
+
+ nvidia,slices:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ HTE lines are arranged in 32 bit slice where each bit represents different
+ line/signal that it can enable/configure for the timestamp. It is u32
+ property and depends on the HTE instance in the chip. The value 3 is for
+ GPIO GTE and 11 for IRQ GTE.
+ enum: [3, 11]
+
+ '#timestamp-cells':
+ description:
+ This represents number of line id arguments as specified by the
+ consumers. For the GTE IRQ, this is IRQ number as mentioned in the
+ SoC technical reference manual. For the GTE GPIO, its value is same as
+ mentioned in the nvidia GPIO device tree binding document.
+ const: 1
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - nvidia,slices
+ - "#timestamp-cells"
+
+additionalProperties: false
+
+examples:
+ - |
+ tegra_hte_aon: timestamp@c1e0000 {
+ compatible = "nvidia,tegra194-gte-aon";
+ reg = <0xc1e0000 0x10000>;
+ interrupts = <0 13 0x4>;
+ nvidia,int-threshold = <1>;
+ nvidia,slices = <3>;
+ #timestamp-cells = <1>;
+ };
+
+ - |
+ tegra_hte_lic: timestamp@3aa0000 {
+ compatible = "nvidia,tegra194-gte-lic";
+ reg = <0x3aa0000 0x10000>;
+ interrupts = <0 11 0x4>;
+ nvidia,int-threshold = <1>;
+ nvidia,slices = <11>;
+ #timestamp-cells = <1>;
+ };
+
+...