Re: [PATCH 1/7] dt-bindings: arm: apple: Add apple,pmgr binding

From: Krzysztof Kozlowski
Date: Wed Oct 06 2021 - 02:57:08 EST


On 05/10/2021 17:59, Hector Martin wrote:
> The PMGR block in Apple Silicon SoCs is responsible for SoC power
> management. There are two PMGRs in T8103, with different register
> layouts but compatible registers. In order to support this as well
> as future SoC generations with backwards-compatible registers, we
> declare these blocks as syscons and bind to individual registers
> in child nodes. Each register controls one SoC device.
>
> The respective apple compatibles are defined in case device-specific
> quirks are necessary in the future, but currently these nodes are
> expected to be bound by the generic syscon driver.
>
> Signed-off-by: Hector Martin <marcan@xxxxxxxxx>
> ---
> .../bindings/arm/apple/apple,pmgr.yaml | 74 +++++++++++++++++++
> MAINTAINERS | 1 +
> 2 files changed, 75 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/arm/apple/apple,pmgr.yaml
>
> diff --git a/Documentation/devicetree/bindings/arm/apple/apple,pmgr.yaml b/Documentation/devicetree/bindings/arm/apple/apple,pmgr.yaml
> new file mode 100644
> index 000000000000..0304164e4140
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/apple/apple,pmgr.yaml
> @@ -0,0 +1,74 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/arm/apple/apple,pmgr.yaml#

Please don't store all Apple-related bindings in bindings/arm/apple, but
instead group per device type like in most of other bindings. In this
case - this looks like something close to power domain controller, so it
should be in bindings/power/

> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Apple SoC Power Manager (PMGR)
> +
> +maintainers:
> + - Hector Martin <marcan@xxxxxxxxx>
> +
> +description: |
> + Apple SoCs include a PMGR block responsible for power management,
> + which can control various clocks, resets, power states, and
> + performance features. This node represents the PMGR as a syscon,
> + with sub-nodes representing individual features.
> +
> + Apple SoCs may have a secondary "mini-PMGR"; it is represented
> + separately in the device tree, but works the same way.
> +
> +select:
> + properties:
> + compatible:
> + contains:
> + enum:
> + - apple,t8103-pmgr
> + - apple,t8103-minipmgr
> + - apple,pmgr
> +
> + required:
> + - compatible
> +
> +properties:
> + $nodename:
> + pattern: "^power-management@[0-9a-f]+$"
> +
> + compatible:
> + items:
> + - enum:
> + - apple,t8103-pmgr
> + - apple,t8103-minipmgr
> + - const: apple,pmgr
> + - const: syscon
> + - const: simple-mfd

No power-domain-cells? Why? What exactly this device is going to do?
Maybe I'll check the driver first.... :)

> +
> + reg:
> + maxItems: 1
> +
> +required:
> + - compatible
> + - reg
> +
> +additionalProperties: true

additionalProperties: false

> +
> +examples:
> + - |
> + soc {
> + #address-cells = <2>;
> + #size-cells = <2>;
> +
> + power-management@23b700000 {
> + compatible = "apple,t8103-pmgr", "apple,pmgr", "syscon", "simple-mfd";
> + #address-cells = <1>;
> + #size-cells = <0>;
> + reg = <0x2 0x3b700000 0x0 0x14000>;
> + };
> +
> + power-management@23b700000 {
> + compatible = "apple,t8103-minipmgr", "apple,pmgr", "syscon", "simple-mfd";
> + #address-cells = <1>;
> + #size-cells = <0>;
> + reg = <0x2 0x3d280000 0x0 0xc000>;
> + };
> + };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index abdcbcfef73d..d25598842d15 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1719,6 +1719,7 @@ B: https://github.com/AsahiLinux/linux/issues
> C: irc://irc.oftc.net/asahi-dev
> T: git https://github.com/AsahiLinux/linux.git
> F: Documentation/devicetree/bindings/arm/apple.yaml
> +F: Documentation/devicetree/bindings/arm/apple/*
> F: Documentation/devicetree/bindings/interrupt-controller/apple,aic.yaml
> F: Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml
> F: arch/arm64/boot/dts/apple/
>


Best regards,
Krzysztof