Re: [PATCH v2 4/7] dt-bindings: soc: mediatek: apusys: Add new document for APU power domain

From: Rob Herring
Date: Thu Apr 15 2021 - 11:25:12 EST


On Thu, Apr 15, 2021 at 01:52:37PM +0800, Flora Fu wrote:
> Document the bindings for APU power domain on MediaTek SoC.
>
> Signed-off-by: Flora Fu <flora.fu@xxxxxxxxxxxx>
> ---
> Note:
> This patch depends on MT8192 clock[1] patches which haven't yet been accepted.
> [1] https://patchwork.kernel.org/project/linux-mediatek/patch/20210324104110.13383-7-chun-jie.chen@xxxxxxxxxxxx/
> ---
> .../soc/mediatek/mediatek,apu-pm.yaml | 145 ++++++++++++++++++
> 1 file changed, 145 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/soc/mediatek/mediatek,apu-pm.yaml
>
> diff --git a/Documentation/devicetree/bindings/soc/mediatek/mediatek,apu-pm.yaml b/Documentation/devicetree/bindings/soc/mediatek/mediatek,apu-pm.yaml
> new file mode 100644
> index 000000000000..6ff966920917
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/mediatek/mediatek,apu-pm.yaml
> @@ -0,0 +1,145 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/soc/mediatek/mediatek,apu-pm.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Mediatek APU Power Domains
> +
> +maintainers:
> + - Flora Fu <flora.fu@xxxxxxxxxxxx>
> +
> +description: |
> + Mediatek AI Process Unit (APU) include support for power domains which can be
> + powered up/down by software.
> + APU subsys belonging to a power domain should contain a 'power-domains'
> + property that is a phandle for apuspm node representing the domain.
> +
> +properties:
> + compatible:
> + items:
> + - enum:
> + - mediatek,mt8192-apu-pm
> + - const: syscon
> +
> + reg:
> + description: Address range of the APU power domain controller.
> + maxItems: 1
> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> + '#power-domain-cells':
> + const: 1
> +
> + vsram-supply:
> + description: apu sram regulator supply.
> +
> + mediatek,scpsys:
> + $ref: /schemas/types.yaml#/definitions/phandle
> + description: |
> + phandle to the device containing the scpsys register range.
> +
> + mediatek,apu-conn:
> + $ref: /schemas/types.yaml#/definitions/phandle
> + description: |
> + phandle to the device containing the scpsys apu conn register range.
> +
> + mediatek,apu-conn1:
> + $ref: /schemas/types.yaml#/definitions/phandle
> + description: |
> + phandle to the device containing the scpsys apu conn1 register range.
> +
> + mediatek,apu-vcore:
> + $ref: /schemas/types.yaml#/definitions/phandle
> + description: |
> + phandle to the device containing the scpsys apu vcore register range.
> +
> +patternProperties:
> + "^power-domain@[0-9a-f]+$":
> + type: object
> + description: |
> + Represents the power domains within the power controller node as
> + documented in Documentation/devicetree/bindings/power/power-domain.yaml.
> +
> + properties:
> + reg:
> + description: |
> + Power domain index. Valid values are defined in:
> + "include/dt-bindings/power/mt8182-apu-power.h"
> + maxItems: 1
> +
> + '#power-domain-cells':
> + description: |
> + Must be 0 for nodes representing a single PM domain and 1 for nodes
> + providing multiple PM.
> +
> + clocks:
> + description: |
> + List of phandles of clocks list. Specify by order according to
> + power-up sequence.
> +
> + clock-names:
> + description: |
> + List of names of clocks. Specify by order according to power-up
> + sequence.
> +
> + assigned-clocks:
> + maxItems: 2
> +
> + assigned-clock-parents:
> + maxItems: 2
> +
> + domain-supply:
> + description: domain regulator supply.
> +
> + required:
> + - reg
> + - '#power-domain-cells'
> +
> + additionalProperties: false
> +
> +required:
> + - compatible
> + - reg
> + - '#power-domain-cells'
> + - vsram-supply
> + - mediatek,scpsys
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/clock/mt8192-clk.h>
> + apuspm: power-domain@190f0000 {
> + compatible = "mediatek,mt8192-apu-pm", "syscon";
> + reg = <0x190f0000 0x1000>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + #power-domain-cells = <1>;

So you have domains provided by this node and then...

> + vsram-supply = <&mt6359_vsram_md_ldo_reg>;
> + mediatek,scpsys = <&scpsys>;
> + mediatek,apu-conn = <&apu_conn>;
> + mediatek,apu-vcore = <&apu_vcore>;
> +
> + apu_top: power-domain@0 {
> + reg = <0>;
> + #power-domain-cells = <0>;

...each child node provides a domain. What's the difference?

> + clocks = <&topckgen CLK_TOP_DSP_SEL>,
> + <&topckgen CLK_TOP_IPU_IF_SEL>,
> + <&clk26m>,
> + <&topckgen CLK_TOP_UNIVPLL_D6_D2>;
> + clock-names = "clk_top_conn",
> + "clk_top_ipu_if",
> + "clk_off",
> + "clk_on_default";
> + assigned-clocks = <&topckgen CLK_TOP_DSP_SEL>,
> + <&topckgen CLK_TOP_IPU_IF_SEL>;
> + assigned-clock-parents = <&topckgen CLK_TOP_UNIVPLL_D6_D2>,
> + <&topckgen CLK_TOP_UNIVPLL_D6_D2>;
> + domain-supply = <&mt6359_vproc1_buck_reg>;
> + };
> + };
> --
> 2.18.0
>