Re: [v4 06/11] dt-binding: pmu: Add RISC-V PMU DT bindings

Rob Herring
2021-10-26T18:57:49Z

On Mon, Oct 25, 2021 at 12:53:45PM -0700, Atish Patra wrote:
> This patch adds the DT bindings for RISC-V PMU driver. It also defines
> the interrupt related properties to allow counter overflow interrupt.
>
> Signed-off-by: Atish Patra <atish.patra@wdc.com>
> ---
> .../devicetree/bindings/perf/riscv,pmu.yaml | 51 +++++++++++++++++++
> 1 file changed, 51 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/perf/riscv,pmu.yaml
>
> diff --git a/Documentation/devicetree/bindings/perf/riscv,pmu.yaml b/Documentation/devicetree/bindings/perf/riscv,pmu.yaml
> new file mode 100644
> index 000000000000..497caad63f16
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/perf/riscv,pmu.yaml
> @@ -0,0 +1,51 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pmu/riscv,pmu.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: RISC-V PMU
> +
> +maintainers:
> + - Atish Patra <atish.patra@wdc.com>
> +
> +description:
> + The "Sscofpmf" extension allows the RISC-V PMU counters to overflow and
> + generate a local interrupt so that event sampling can be done from user-space.
> + The above said ISA extension is an optional extension to maintain backward
> + compatibility and will be included in privilege specification v1.12 . That's
> + why the interrupt property is marked as optional. The platforms with sscofpmf
> + extension should add this property to enable event sampling.
> + The device tree node with the compatible string is mandatory for any platform
> + that wants to use pmu counter start/stop methods using SBI PMU extension.
> +
> +properties:
> + compatible:
> + enum:
> + - riscv,pmu

Only 1 version? Every implementation detail is discoverable in other
ways?

> +
> + description:
> + Should be "riscv,pmu".

Don't write free form text of what the schema says.

> +
> + interrupts-extended:
> + minItems: 1
> + maxItems: 4095
> +
> +additionalProperties: false
> +
> +required:
> + - None
> +optional:

No a json-schema keyword.

> + - compatible
> + - interrupts-extended
> +
> +examples:
> + - |
> + pmu {
> + compatible = "riscv,pmu";
> + interrupts-extended = <&cpu0intc 13>,
> + <&cpu1intc 13>,
> + <&cpu2intc 13>,
> + <&cpu3intc 13>;
> + };
> +...
> --
> 2.31.1
>
>