Re: [PATCH net-next 1/7] dt-binding: ti: am65x: document common platform time sync cpts module

Rob Herring
2020-05-05T04:04:30Z

On Fri, May 01, 2020 at 11:50:05PM +0300, Grygorii Strashko wrote:
> Document device tree bindings for TI AM654/J721E SoC The Common Platform
> Time Sync (CPTS) module. The CPTS module is used to facilitate host control
> of time sync operations. Main features of CPTS module are:
> - selection of multiple external clock sources
> - 64-bit timestamp mode in ns with ppm and nudge adjustment.
> - control of time sync events via interrupt or polling
> - hardware timestamp of ext. events (HWx_TS_PUSH)
> - periodic generator function outputs (TS_GENFx)
> - PPS in combination with timesync router
> - Depending on integration it enables compliance with the IEEE 1588-2008
> standard for a precision clock synchronization protocol, Ethernet Enhanced
> Scheduled Traffic Operations (CPTS_ESTFn) and PCIe Subsystem Precision Time
> Measurement (PTM).
>
> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
> ---
> .../bindings/net/ti,k3-am654-cpsw-nuss.yaml | 7 +
> .../bindings/net/ti,k3-am654-cpts.yaml | 152 ++++++++++++++++++
> 2 files changed, 159 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml
>
> diff --git a/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml b/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml
> index 78bf511e2892..0f3fde45e200 100644
> --- a/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml
> +++ b/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml
> @@ -144,6 +144,13 @@ patternProperties:
> description:
> CPSW MDIO bus.
>
> + "^cpts$":

Fixed strings go under 'properties'.

> + type: object
> + allOf:
> + - $ref: "ti,am654-cpts.yaml#"
> + description:
> + CPSW Common Platform Time Sync (CPTS) module.
> +
> required:
> - compatible
> - reg
> diff --git a/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml b/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml
> new file mode 100644
> index 000000000000..1b535d41e5c6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/ti,k3-am654-cpts.yaml
> @@ -0,0 +1,152 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/ti,am654-cpts.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: The TI AM654x/J721E Common Platform Time Sync (CPTS) module Device Tree Bindings
> +
> +maintainers:
> + - Grygorii Strashko <grygorii.strashko@ti.com>
> + - Sekhar Nori <nsekhar@ti.com>
> +
> +description: |+
> + The TI AM654x/J721E CPTS module is used to facilitate host control of time
> + sync operations.
> + Main features of CPTS module are
> + - selection of multiple external clock sources
> + - Software control of time sync events via interrupt or polling
> + - 64-bit timestamp mode in ns with PPM and nudge adjustment.
> + - hardware timestamp push inputs (HWx_TS_PUSH)
> + - timestamp counter compare output (TS_COMP)
> + - timestamp counter bit output (TS_SYNC)
> + - periodic Generator function outputs (TS_GENFx)
> + - Ethernet Enhanced Scheduled Traffic Operations (CPTS_ESTFn) (TSN)
> + - external hardware timestamp push inputs (HWx_TS_PUSH) timestamping
> +
> + Depending on integration it enables compliance with the IEEE 1588-2008
> + standard for a precision clock synchronization protocol, Ethernet Enhanced
> + Scheduled Traffic Operations (CPTS_ESTFn) and PCIe Subsystem Precision Time
> + Measurement (PTM).
> +
> + TI AM654x/J721E SoCs has several similar CPTS modules integrated into the
> + different parts of the system which could be synchronized with each other
> + - Main CPTS
> + - MCU CPSW CPTS with IEEE 1588-2008 support
> + - PCIe subsystem CPTS for PTM support
> +
> + Depending on CPTS module integration and when CPTS is integral part of
> + another module (MCU CPSW for example) "compatible" and "reg" can
> + be omitted - parent module is fully responsible for CPTS enabling and
> + configuration.

That's fine, but you should still have compatible and reg.

> +
> +properties:
> + $nodename:
> + pattern: "^cpts(@.*|-[0-9a-f])*$"
> +
> + compatible:
> + oneOf:
> + - const: ti,am65-cpts
> + - const: ti,j721e-cpts
> +
> + reg:
> + maxItems: 1
> + description:
> + The physical base address and size of CPTS IO range

Wrong indentation.

> +
> + reg-names:
> + items:
> + - const: cpts

Don't really need *-names when there's only one and you haven't picked
very meaningful names.

> +
> + clocks:
> + description: CPTS reference clock
> +
> + clock-names:
> + items:
> + - const: cpts
> +
> + interrupts-extended:

Use 'interrupts' here, the tooling will fixup things to allow both.

> + items:
> + - description: CPTS events interrupt
> +
> + interrupt-names:
> + items:
> + - const: "cpts"

Don't need quotes.

> +
> + ti,cpts-ext-ts-inputs:
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + maximum: 8
> + description:
> + Number of hardware timestamp push inputs (HWx_TS_PUSH)

Wrong indentation.

> +
> + ti,cpts-periodic-outputs:
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> + maximum: 8
> + description:
> + Number of timestamp Generator function outputs (TS_GENFx)

Wrong indentation.

> +
> + refclk-mux:
> + type: object
> + description: CPTS reference clock multiplexer clock
> + properties:
> + '#clock-cells':
> + const: 0
> +
> + clocks:
> + maxItems: 8
> +
> + assigned-clocks:
> + maxItems: 1
> +
> + assigned-clocks-parents:
> + maxItems: 1
> +
> + required:
> + - clocks
> +
> +required:
> + - clocks
> + - clock-names
> + - interrupts-extended
> + - interrupt-names
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/interrupt-controller/irq.h>
> + #include <dt-bindings/interrupt-controller/arm-gic.h>
> +
> + cpts@310d0000 {
> + compatible = "ti,am65-cpts";
> + reg = <0x0 0x310d0000 0x0 0x400>;
> + reg-names = "cpts";
> + clocks = <&main_cpts_mux>;
> + clock-names = "cpts";
> + interrupts-extended = <&k3_irq 163 0 IRQ_TYPE_LEVEL_HIGH>;
> + interrupt-names = "cpts";
> + ti,cpts-periodic-outputs = <6>;
> + ti,cpts-ext-ts-inputs = <8>;
> +
> + main_cpts_mux: refclk-mux {
> + #clock-cells = <0>;
> + clocks = <&k3_clks 118 5>, <&k3_clks 118 11>,
> + <&k3_clks 157 91>, <&k3_clks 157 77>,
> + <&k3_clks 157 102>, <&k3_clks 157 80>,
> + <&k3_clks 120 3>, <&k3_clks 121 3>;
> + assigned-clocks = <&main_cpts_mux>;
> + assigned-clock-parents = <&k3_clks 118 11>;
> + };
> + };
> + - |
> +
> + cpts {
> + clocks = <&k3_clks 18 2>;
> + clock-names = "cpts";
> + interrupts-extended = <&gic500 GIC_SPI 858 IRQ_TYPE_LEVEL_HIGH>;
> + interrupt-names = "cpts";
> + ti,cpts-ext-ts-inputs = <4>;
> + ti,cpts-periodic-outputs = <2>;

How is this example accessed?

> + };
> --
> 2.17.1