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". Signed-off-by: Hector Martin <marcan@xxxxxxxxx> --- .../bindings/power/apple,pmgr-pwrstate.yaml | 117 ++++++++++++++++++ MAINTAINERS | 1 + 2 files changed, 118 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..a14bf5f30ff0 --- /dev/null +++ b/Documentation/devicetree/bindings/power/apple,pmgr-pwrstate.yaml @@ -0,0 +1,117 @@ +# 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 a PMGR block 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. + + IP cores belonging to a power domain should contain a + "power-domains" property that is a phandle for the + power domain node representing the domain. + +properties: + $nodename: + pattern: "^power-controller@[0-9a-f]+$" + + compatible: + items: + - enum: + - apple,t8103-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. + + apple,domain-name: + description: | + Specifies the name of the SoC device being controlled. This is used to + name the power/reset domains. + $ref: /schemas/types.yaml#/definitions/string + + apple,always-on: + description: | + Forces this power domain to always be powered up. + type: boolean + +required: + - compatible + - reg + - "#power-domain-cells" + - "#reset-cells" + - "apple,domain-name" + +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>; + + ps_sio: power-controller@1c0 { + compatible = "apple,t8103-pmgr-pwrstate", "apple,pmgr-pwrstate"; + reg = <0x1c0>; + #power-domain-cells = <0>; + #reset-cells = <0>; + apple,domain-name = "sio"; + apple,always-on; + }; + + ps_uart_p: power-controller@220 { + compatible = "apple,t8103-pmgr-pwrstate", "apple,pmgr-pwrstate"; + reg = <0x220>; + #power-domain-cells = <0>; + #reset-cells = <0>; + apple,domain-name = "uart_p"; + power-domains = <&ps_sio>; + }; + + ps_uart0: power-controller@270 { + compatible = "apple,t8103-pmgr-pwrstate", "apple,pmgr-pwrstate"; + reg = <0x270>; + #power-domain-cells = <0>; + #reset-cells = <0>; + apple,domain-name = "uart0"; + power-domains = <&ps_uart_p>; + }; + }; + }; diff --git a/MAINTAINERS b/MAINTAINERS index d25598842d15..5fe53d9a2956 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1722,6 +1722,7 @@ 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: Documentation/devicetree/bindings/power/apple* F: arch/arm64/boot/dts/apple/ F: drivers/irqchip/irq-apple-aic.c F: include/dt-bindings/interrupt-controller/apple-aic.h -- 2.33.0
