This binding represents the cpufreq/DVFS hardware present in Apple SoCs. The hardware has an independent controller per CPU cluster, and we represent them as unique nodes in order to accurately describe the hardware. The driver is responsible for binding them as a single cpufreq device (in the Linux cpufreq model). Acked-by: Marc Zyngier <maz@xxxxxxxxxx> Signed-off-by: Hector Martin <marcan@xxxxxxxxx> --- .../cpufreq/apple,cluster-cpufreq.yaml | 117 ++++++++++++++++++ 1 file changed, 117 insertions(+) create mode 100644 Documentation/devicetree/bindings/cpufreq/apple,cluster-cpufreq.yaml diff --git a/Documentation/devicetree/bindings/cpufreq/apple,cluster-cpufreq.yaml b/Documentation/devicetree/bindings/cpufreq/apple,cluster-cpufreq.yaml new file mode 100644 index 000000000000..76cb9726660e --- /dev/null +++ b/Documentation/devicetree/bindings/cpufreq/apple,cluster-cpufreq.yaml @@ -0,0 +1,117 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/cpufreq/apple,cluster-cpufreq.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Apple SoC cluster cpufreq device + +maintainers: + - Hector Martin <marcan@xxxxxxxxx> + +description: | + Apple SoCs (e.g. M1) have a per-cpu-cluster DVFS controller that is part of + the cluster management register block. This binding uses the standard + operating-points-v2 table to define the CPU performance states, with the + opp-level property specifying the hardware p-state index for that level. + +properties: + compatible: + oneOf: + - items: + - enum: + - apple,t8103-cluster-cpufreq + - apple,t8112-cluster-cpufreq + - const: apple,cluster-cpufreq + - items: + - const: apple,t6000-cluster-cpufreq + - const: apple,t8103-cluster-cpufreq + - const: apple,cluster-cpufreq + + reg: + maxItems: 1 + + '#performance-domain-cells': + const: 0 + +required: + - compatible + - reg + - '#performance-domain-cells' + +additionalProperties: false + +examples: + - | + // This example shows a single CPU per domain and 2 domains, + // with two p-states per domain. + // Shipping hardware has 2-4 CPUs per domain and 2-6 domains. + cpus { + #address-cells = <2>; + #size-cells = <0>; + + cpu@0 { + compatible = "apple,icestorm"; + device_type = "cpu"; + reg = <0x0 0x0>; + operating-points-v2 = <&ecluster_opp>; + performance-domains = <&cpufreq_e>; + }; + + cpu@10100 { + compatible = "apple,firestorm"; + device_type = "cpu"; + reg = <0x0 0x10100>; + operating-points-v2 = <&pcluster_opp>; + performance-domains = <&cpufreq_p>; + }; + }; + + ecluster_opp: opp-table-0 { + compatible = "operating-points-v2"; + opp-shared; + + opp01 { + opp-hz = /bits/ 64 <600000000>; + opp-level = <1>; + clock-latency-ns = <7500>; + }; + opp02 { + opp-hz = /bits/ 64 <972000000>; + opp-level = <2>; + clock-latency-ns = <22000>; + }; + }; + + pcluster_opp: opp-table-1 { + compatible = "operating-points-v2"; + opp-shared; + + opp01 { + opp-hz = /bits/ 64 <600000000>; + opp-level = <1>; + clock-latency-ns = <8000>; + }; + opp02 { + opp-hz = /bits/ 64 <828000000>; + opp-level = <2>; + clock-latency-ns = <19000>; + }; + }; + + soc { + #address-cells = <2>; + #size-cells = <2>; + + cpufreq_e: performance-controller@210e20000 { + compatible = "apple,t8103-cluster-cpufreq", "apple,cluster-cpufreq"; + reg = <0x2 0x10e20000 0 0x1000>; + #performance-domain-cells = <0>; + }; + + cpufreq_p: performance-controller@211e20000 { + compatible = "apple,t8103-cluster-cpufreq", "apple,cluster-cpufreq"; + reg = <0x2 0x11e20000 0 0x1000>; + #performance-domain-cells = <0>; + }; + }; -- 2.35.1
