1 files changed, 104 insertions, 0 deletions
diff --git a/dts/Bindings/arm/psci.yaml b/dts/Bindings/arm/psci.yaml
index 7abdf58b33..8ef85420b2 100644
--- a/dts/Bindings/arm/psci.yaml
+++ b/dts/Bindings/arm/psci.yaml
@@ -102,6 +102,34 @@ properties:
       [1] Kernel documentation - ARM idle states bindings
         Documentation/devicetree/bindings/arm/idle-states.txt
 
+  "#power-domain-cells":
+    description:
+      The number of cells in a PM domain specifier as per binding in [3].
+      Must be 0 as to represent a single PM domain.
+
+      ARM systems can have multiple cores, sometimes in an hierarchical
+      arrangement. This often, but not always, maps directly to the processor
+      power topology of the system. Individual nodes in a topology have their
+      own specific power states and can be better represented hierarchically.
+
+      For these cases, the definitions of the idle states for the CPUs and the
+      CPU topology, must conform to the binding in [3]. The idle states
+      themselves must conform to the binding in [4] and must specify the
+      arm,psci-suspend-param property.
+
+      It should also be noted that, in PSCI firmware v1.0 the OS-Initiated
+      (OSI) CPU suspend mode is introduced. Using a hierarchical representation
+      helps to implement support for OSI mode and OS implementations may choose
+      to mandate it.
+
+      [3] Documentation/devicetree/bindings/power/power_domain.txt
+      [4] Documentation/devicetree/bindings/power/domain-idle-state.txt
+
+  power-domains:
+    $ref: '/schemas/types.yaml#/definitions/phandle-array'
+    description:
+      List of phandles and PM domain specifiers, as defined by bindings of the
+      PM domain provider.
 
 required:
   - compatible
@@ -160,4 +188,80 @@ examples:
       cpu_on = <0x95c10002>;
       cpu_off = <0x95c10001>;
     };
+
+  - |+
+
+    // Case 4: CPUs and CPU idle states described using the hierarchical model.
+
+    cpus {
+      #size-cells = <0>;
+      #address-cells = <1>;
+
+      CPU0: cpu@0 {
+        device_type = "cpu";
+        compatible = "arm,cortex-a53", "arm,armv8";
+        reg = <0x0>;
+        enable-method = "psci";
+        power-domains = <&CPU_PD0>;
+        power-domain-names = "psci";
+      };
+
+      CPU1: cpu@1 {
+        device_type = "cpu";
+        compatible = "arm,cortex-a57", "arm,armv8";
+        reg = <0x100>;
+        enable-method = "psci";
+        power-domains = <&CPU_PD1>;
+        power-domain-names = "psci";
+      };
+
+      idle-states {
+
+        CPU_PWRDN: cpu-power-down {
+          compatible = "arm,idle-state";
+          arm,psci-suspend-param = <0x0000001>;
+          entry-latency-us = <10>;
+          exit-latency-us = <10>;
+          min-residency-us = <100>;
+        };
+
+        CLUSTER_RET: cluster-retention {
+          compatible = "domain-idle-state";
+          arm,psci-suspend-param = <0x1000011>;
+          entry-latency-us = <500>;
+          exit-latency-us = <500>;
+          min-residency-us = <2000>;
+        };
+
+        CLUSTER_PWRDN: cluster-power-down {
+          compatible = "domain-idle-state";
+          arm,psci-suspend-param = <0x1000031>;
+          entry-latency-us = <2000>;
+          exit-latency-us = <2000>;
+          min-residency-us = <6000>;
+        };
+      };
+    };
+
+    psci {
+      compatible = "arm,psci-1.0";
+      method = "smc";
+
+      CPU_PD0: cpu-pd0 {
+        #power-domain-cells = <0>;
+        domain-idle-states = <&CPU_PWRDN>;
+        power-domains = <&CLUSTER_PD>;
+      };
+
+      CPU_PD1: cpu-pd1 {
+        #power-domain-cells = <0>;
+        domain-idle-states =  <&CPU_PWRDN>;
+        power-domains = <&CLUSTER_PD>;
+      };
+
+      CLUSTER_PD: cluster-pd {
+        #power-domain-cells = <0>;
+        domain-idle-states = <&CLUSTER_RET>, <&CLUSTER_PWRDN>;
+      };
+    };
 ...