This syscon child node represents a single SoC device controlled by the PMGR block. This layout allows us to declare all device power state controls (power/clock gating and reset) in the device tree, including dependencies, instead of hardcoding it into the driver. The register layout is uniform. Each pmgr-pwrstate node provides genpd and reset features, to be consumed by downstream device nodes. Future SoCs are expected to use backwards compatible registers, and the "apple,pmgr-pwrstate" represents any such interfaces (possibly with additional features gated by the more specific compatible), allowing them to be bound without driver updates. If a backwards incompatible change is introduced in future SoCs, it will require a new compatible, such as "apple,pmgr-pwrstate-v2". Reviewed-by: Mark Kettenis <kettenis@xxxxxxxxxxx> Reviewed-by: Rob Herring <robh@xxxxxxxxxx> Signed-off-by: Hector Martin <marcan@xxxxxxxxx> --- .../bindings/power/apple,pmgr-pwrstate.yaml | 71 +++++++++++++++++++ 1 file changed, 71 insertions(+) create mode 100644 Documentation/devicetree/bindings/power/apple,pmgr-pwrstate.yaml diff --git a/Documentation/devicetree/bindings/power/apple,pmgr-pwrstate.yaml b/Documentation/devicetree/bindings/power/apple,pmgr-pwrstate.yaml new file mode 100644 index 000000000000..5056d08b8261 --- /dev/null +++ b/Documentation/devicetree/bindings/power/apple,pmgr-pwrstate.yaml @@ -0,0 +1,71 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/power/apple,pmgr-pwrstate.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Apple SoC PMGR Power States + +maintainers: + - Hector Martin <marcan@xxxxxxxxx> + +allOf: + - $ref: "power-domain.yaml#" + +description: | + Apple SoCs include PMGR blocks responsible for power management, + which can control various clocks, resets, power states, and + performance features. This binding describes the device power + state registers, which control power states and resets. + + Each instance of a power controller within the PMGR syscon node + represents a generic power domain provider, as documented in + Documentation/devicetree/bindings/power/power-domain.yaml. + The provider controls a single SoC block. The power hierarchy is + represented via power-domains relationships between these nodes. + + See Documentation/devicetree/bindings/arm/apple/apple,pmgr.yaml + for the top-level PMGR node documentation. + +properties: + compatible: + items: + - enum: + - apple,t8103-pmgr-pwrstate + - apple,t6000-pmgr-pwrstate + - const: apple,pmgr-pwrstate + + reg: + maxItems: 1 + + "#power-domain-cells": + const: 0 + + "#reset-cells": + const: 0 + + power-domains: + description: + Reference to parent power domains. A domain may have multiple parents, + and all will be powered up when it is powered. + minItems: 1 + maxItems: 8 # Arbitrary, should be enough + + label: + description: + Specifies the name of the SoC domain being controlled. This is used to + name the power/reset domains. + + apple,always-on: + description: + Forces this power domain to always be powered up. + type: boolean + +required: + - compatible + - reg + - "#power-domain-cells" + - "#reset-cells" + - label + +additionalProperties: false -- 2.33.0
