dt-bindings: power: Add bindings for the Mediatek SCPSYS power domains controller

The System Control Processor System (SCPSYS) has several power management
related tasks in the system. Add the bindings to define the power
domains for the SCPSYS power controller.

Co-developed-by: Matthias Brugger <[e-mail]>
Signed-off-by: Matthias Brugger <[e-mail]>
Signed-off-by: Enric Balletbo i Serra <[e-mail]>
Reviewed-by: Rob Herring <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Matthias Brugger <[e-mail]>

Documentation/devicetree/bindings/power/mediatek,power-controller.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/power/mediatek,power-controller.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Mediatek Power Domains Controller
+
+maintainers:
+  - Weiyi Lu <[e-mail]>
+  - Matthias Brugger <[e-mail]>
+
+description: |
+  Mediatek processors include support for multiple power domains which can be
+  powered up/down by software based on different application scenes to save power.
+
+  IP cores belonging to a power domain should contain a 'power-domains'
+  property that is a phandle for SCPSYS node representing the domain.
+
+properties:
+  $nodename:
+    const: power-controller
+
+  compatible:
+    enum:
+      - mediatek,mt8173-power-controller
+
+  '#power-domain-cells':
+    const: 1
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+patternProperties:
+  "^power-domain@[0-9a-f]+$":
+    type: object
+    description: |
+      Represents the power domains within the power controller node as documented
+      in Documentation/devicetree/bindings/power/power-domain.yaml.
+
+    properties:
+
+      '#power-domain-cells':
+        description:
+          Must be 0 for nodes representing a single PM domain and 1 for nodes
+          providing multiple PM domains.
+
+      '#address-cells':
+        const: 1
+
+      '#size-cells':
+        const: 0
+
+      reg:
+        description: |
+          Power domain index. Valid values are defined in:
+              "include/dt-bindings/power/mt8173-power.h" - for MT8173 type power domain.
+        maxItems: 1
+
+      clocks:
+        description: |
+          A number of phandles to clocks that need to be enabled during domain
+          power-up sequencing.
+
+      clock-names:
+        description: |
+          List of names of clocks, in order to match the power-up sequencing
+          for each power domain we need to group the clocks by name. BASIC
+          clocks need to be enabled before enabling the corresponding power
+          domain, and should not have a '-' in their name (i.e mm, mfg, venc).
+          SUSBYS clocks need to be enabled before releasing the bus protection,
+          and should contain a '-' in their name (i.e mm-0, isp-0, cam-0).
+
+          In order to follow properly the power-up sequencing, the clocks must
+          be specified by order, adding first the BASIC clocks followed by the
+          SUSBSYS clocks.
+
+      mediatek,infracfg:
+        $ref: /schemas/types.yaml#definitions/phandle
+        description: phandle to the device containing the INFRACFG register range.
+
+      mediatek,smi:
+        $ref: /schemas/types.yaml#definitions/phandle
+        description: phandle to the device containing the SMI register range.
+
+    patternProperties:
+      "^power-domain@[0-9a-f]+$":
+        type: object
+        description: |
+          Represents a power domain child within a power domain parent node.
+
+        properties:
+
+          '#power-domain-cells':
+            description:
+              Must be 0 for nodes representing a single PM domain and 1 for nodes
+              providing multiple PM domains.
+
+          '#address-cells':
+            const: 1
+
+          '#size-cells':
+            const: 0
+
+          reg:
+            maxItems: 1
+
+          clocks:
+            description: |
+              A number of phandles to clocks that need to be enabled during domain
+              power-up sequencing.
+
+          clock-names:
+            description: |
+              List of names of clocks, in order to match the power-up sequencing
+              for each power domain we need to group the clocks by name. BASIC
+              clocks need to be enabled before enabling the corresponding power
+              domain, and should not have a '-' in their name (i.e mm, mfg, venc).
+              SUSBYS clocks need to be enabled before releasing the bus protection,
+              and should contain a '-' in their name (i.e mm-0, isp-0, cam-0).
+
+              In order to follow properly the power-up sequencing, the clocks must
+              be specified by order, adding first the BASIC clocks followed by the
+              SUSBSYS clocks.
+
+          mediatek,infracfg:
+            $ref: /schemas/types.yaml#definitions/phandle
+            description: phandle to the device containing the INFRACFG register range.
+
+          mediatek,smi:
+            $ref: /schemas/types.yaml#definitions/phandle
+            description: phandle to the device containing the SMI register range.
+
+        patternProperties:
+          "^power-domain@[0-9a-f]+$":
+            type: object
+            description: |
+              Represents a power domain child within a power domain parent node.
+
+            properties:
+
+              '#power-domain-cells':
+                description:
+                  Must be 0 for nodes representing a single PM domain and 1 for nodes
+                  providing multiple PM domains.
+
+              '#address-cells':
+                const: 1
+
+              '#size-cells':
+                const: 0
+
+              reg:
+                maxItems: 1
+
+              clocks:
+                description: |
+                  A number of phandles to clocks that need to be enabled during domain
+                  power-up sequencing.
+
+              clock-names:
+                description: |
+                  List of names of clocks, in order to match the power-up sequencing
+                  for each power domain we need to group the clocks by name. BASIC
+                  clocks need to be enabled before enabling the corresponding power
+                  domain, and should not have a '-' in their name (i.e mm, mfg, venc).
+                  SUSBYS clocks need to be enabled before releasing the bus protection,
+                  and should contain a '-' in their name (i.e mm-0, isp-0, cam-0).
+
+                  In order to follow properly the power-up sequencing, the clocks must
+                  be specified by order, adding first the BASIC clocks followed by the
+                  SUSBSYS clocks.
+
+              mediatek,infracfg:
+                $ref: /schemas/types.yaml#definitions/phandle
+                description: phandle to the device containing the INFRACFG register range.
+
+              mediatek,smi:
+                $ref: /schemas/types.yaml#definitions/phandle
+                description: phandle to the device containing the SMI register range.
+
+            required:
+              - reg
+
+            additionalProperties: false
+
+        required:
+          - reg
+
+        additionalProperties: false
+
+    required:
+      - reg
+
+    additionalProperties: false
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/mt8173-clk.h>
+    #include <dt-bindings/power/mt8173-power.h>
+
+    soc {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        scpsys: syscon@10006000 {
+            compatible = "syscon", "simple-mfd";
+            reg = <0 0x10006000 0 0x1000>;
+
+            spm: power-controller {
+                compatible = "mediatek,mt8173-power-controller";
+                #address-cells = <1>;
+                #size-cells = <0>;
+                #power-domain-cells = <1>;
+
+                /* power domains of the SoC */
+                power-domain@MT8173_POWER_DOMAIN_VDEC {
+                    reg = <MT8173_POWER_DOMAIN_VDEC>;
+                    clocks = <&topckgen CLK_TOP_MM_SEL>;
+                    clock-names = "mm";
+                    #power-domain-cells = <0>;
+                };
+                power-domain@MT8173_POWER_DOMAIN_VENC {
+                    reg = <MT8173_POWER_DOMAIN_VENC>;
+                    clocks = <&topckgen CLK_TOP_MM_SEL>,
+                             <&topckgen CLK_TOP_VENC_SEL>;
+                    clock-names = "mm", "venc";
+                    #power-domain-cells = <0>;
+                };
+                power-domain@MT8173_POWER_DOMAIN_ISP {
+                    reg = <MT8173_POWER_DOMAIN_ISP>;
+                    clocks = <&topckgen CLK_TOP_MM_SEL>;
+                    clock-names = "mm";
+                    #power-domain-cells = <0>;
+                };
+                power-domain@MT8173_POWER_DOMAIN_MM {
+                    reg = <MT8173_POWER_DOMAIN_MM>;
+                    clocks = <&topckgen CLK_TOP_MM_SEL>;
+                    clock-names = "mm";
+                    #power-domain-cells = <0>;
+                    mediatek,infracfg = <&infracfg>;
+                };
+                power-domain@MT8173_POWER_DOMAIN_VENC_LT {
+                    reg = <MT8173_POWER_DOMAIN_VENC_LT>;
+                    clocks = <&topckgen CLK_TOP_MM_SEL>,
+                             <&topckgen CLK_TOP_VENC_LT_SEL>;
+                    clock-names = "mm", "venclt";
+                    #power-domain-cells = <0>;
+                };
+                power-domain@MT8173_POWER_DOMAIN_AUDIO {
+                    reg = <MT8173_POWER_DOMAIN_AUDIO>;
+                    #power-domain-cells = <0>;
+                };
+                power-domain@MT8173_POWER_DOMAIN_USB {
+                    reg = <MT8173_POWER_DOMAIN_USB>;
+                    #power-domain-cells = <0>;
+                };
+                power-domain@MT8173_POWER_DOMAIN_MFG_ASYNC {
+                    reg = <MT8173_POWER_DOMAIN_MFG_ASYNC>;
+                    clocks = <&clk26m>;
+                    clock-names = "mfg";
+                    #address-cells = <1>;
+                    #size-cells = <0>;
+                    #power-domain-cells = <1>;
+
+                    power-domain@MT8173_POWER_DOMAIN_MFG_2D {
+                        reg = <MT8173_POWER_DOMAIN_MFG_2D>;
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+                        #power-domain-cells = <1>;
+
+                        power-domain@MT8173_POWER_DOMAIN_MFG {
+                            reg = <MT8173_POWER_DOMAIN_MFG>;
+                            #power-domain-cells = <0>;
+                            mediatek,infracfg = <&infracfg>;
+                        };
+                    };
+                };
+            };
+        };
+    };