[PATCH v9 2/3] dt-bindings: mfd: aspeed,ast2x00-scu: Describe AST2700 SCU0

AST2700 consists of two interconnected SoC instances, each with its own
System Control Unit (SCU). The SCU0 provides pin control, interrupt
controllers, clocks, resets, and address-space mappings for the
Secondary and Tertiary Service Processors (SSP and TSP).

Describe the SSP/TSP address mappings using the standard
memory-region and memory-region-names properties.

Disallow legacy child nodes that are not present on AST2700, including
p2a-control and smp-memram. The latter is unnecessary as software can
access the scratch registers via the SCU syscon.

Also allow the AST2700 SoC0 pin controller to be described as a child
node of the SCU0, and add an example illustrating the SCU0 layout,
including reserved-memory, interrupt controllers, and pinctrl.

Reviewed-by: Rob Herring (Arm) <[email protected]>
Signed-off-by: Billy Tsai <[email protected]>
---
 .../bindings/mfd/aspeed,ast2x00-scu.yaml           | 114 +++++++++++++++++++++
 1 file changed, 114 insertions(+)

diff --git a/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml b/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
index a87f31fce019..0d5e168b0309 100644
--- a/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
+++ b/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
@@ -46,6 +46,18 @@ properties:
   '#reset-cells':
     const: 1
 
+  memory-region:
+    items:
+      - description: Region mapped through the first SSP address window.
+      - description: Region mapped through the second SSP address window.
+      - description: Region mapped through the TSP address window.
+
+  memory-region-names:
+    items:
+      - const: ssp-0
+      - const: ssp-1
+      - const: tsp
+
 patternProperties:
   '^p2a-control@[0-9a-f]+$':
     description: >
@@ -87,6 +99,7 @@ patternProperties:
             - aspeed,ast2400-pinctrl
             - aspeed,ast2500-pinctrl
             - aspeed,ast2600-pinctrl
+            - aspeed,ast2700-soc0-pinctrl
 
     required:
       - compatible
@@ -156,6 +169,30 @@ required:
   - '#clock-cells'
   - '#reset-cells'
 
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - aspeed,ast2700-scu0
+              - aspeed,ast2700-scu1
+    then:
+      patternProperties:
+        '^p2a-control@[0-9a-f]+$': false
+        '^smp-memram@[0-9a-f]+$': false
+
+  - if:
+      not:
+        properties:
+          compatible:
+            contains:
+              const: aspeed,ast2700-scu0
+    then:
+      properties:
+        memory-region: false
+        memory-region-names: false
+
 additionalProperties: false
 
 examples:
@@ -180,4 +217,81 @@ examples:
             reg = <0x7c 0x4>, <0x150 0x8>;
         };
     };
+
+  - |
+    / {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        reserved-memory {
+            #address-cells = <2>;
+            #size-cells = <2>;
+            ranges;
+
+            ssp_region_0: memory@400000000 {
+                reg = <0x4 0x00000000 0x0 0x01000000>;
+                no-map;
+            };
+
+            ssp_region_1: memory@401000000 {
+                reg = <0x4 0x01000000 0x0 0x01000000>;
+                no-map;
+            };
+
+            tsp_region: memory@402000000 {
+                reg = <0x4 0x02000000 0x0 0x01000000>;
+                no-map;
+            };
+        };
+
+        bus {
+            #address-cells = <2>;
+            #size-cells = <2>;
+
+            syscon@12c02000 {
+                compatible = "aspeed,ast2700-scu0", "syscon", "simple-mfd";
+                reg = <0 0x12c02000 0 0x1000>;
+                ranges = <0x0 0x0 0x12c02000 0x1000>;
+                #address-cells = <1>;
+                #size-cells = <1>;
+                #clock-cells = <1>;
+                #reset-cells = <1>;
+
+                memory-region = <&ssp_region_0>, <&ssp_region_1>,
+                                <&tsp_region>;
+                memory-region-names = "ssp-0", "ssp-1", "tsp";
+
+                silicon-id@0 {
+                    compatible = "aspeed,ast2700-silicon-id", "aspeed,silicon-id";
+                    reg = <0x0 0x4>;
+                };
+
+                interrupt-controller@1b0 {
+                    compatible = "aspeed,ast2700-scu-ic0";
+                    reg = <0x1b0 0x4>;
+                    #interrupt-cells = <1>;
+                    interrupts-extended = <&intc0 97>;
+                    interrupt-controller;
+                };
+
+                interrupt-controller@1e0 {
+                    compatible = "aspeed,ast2700-scu-ic1";
+                    reg = <0x1e0 0x4>;
+                    #interrupt-cells = <1>;
+                    interrupts-extended = <&intc0 98>;
+                    interrupt-controller;
+                };
+
+                pinctrl@400 {
+                    compatible = "aspeed,ast2700-soc0-pinctrl";
+                    reg = <0x400 0x318>;
+                    emmc-state {
+                        function = "EMMC";
+                        groups = "EMMCG1";
+                    };
+                };
+            };
+        };
+    };
+
 ...

-- 
2.34.1