Subject: Re: [PATCH v3 1/2] dt-bindings: interrupt-controller: aspeed: Add
parent node compatibles and refine documentation

On Tue, Jul 22, 2025 at 05:51:55PM +0800, Ryan Chen wrote:

quoted

The AST2700 SoC contains two independent top-level interrupt
controllers
(INTC0 and INTC1), each responsible for handling different peripheral
groups and occupying separate register spaces. Above them, PSP(CA35)
GIC controller acts as the root interrupt aggregator. Accurately
describing this hierarchical hardware structure in the device tree
requires distinct compatible strings for the parent nodes of INTC0 and INTC1.

- Adds 'aspeed,ast2700-intc0' and 'aspeed,ast2700-intc1' compatible
strings for parent interrupt controller nodes. (in addition to the
existing 'aspeed,ast2700-intc-ic' for child nodes)
- Clarifies the relationship and function of INTC0 parent
 (intc0_0~x: child), INTC1 parent (intc1_0~x: child), and the GIC  in
the documentation.
- Updates block diagrams and device tree examples to illustrate  the
hierarchy and compatible usage.
- Refines documentation and example formatting.

This change allows the device tree and driver to distinguish between
parent (top-level) and child (group) interrupt controller nodes,
enabling more precise driver matching SOC register space allocation.

That's nice, but is an ABI break.

Sorry, Is it an ABI break?
I keep the compatible aspeed,ast2700-intc-ic, not change it.
Just move it to be child, and make aspeed,ast2700-intc0/1 to be parent for aspeed,ast2700-intc-ic.

Older : https://github.com/torvalds/linux/blob/master/Documentation/devicetree/bindings/interrupt-controller/aspeed%2Cast2700-intc.yaml#L70C2-L86C7
     bus {
        #address-cells = <2>;
        #size-cells = <2>;

        interrupt-controller@12101b00 {
            compatible = "aspeed,ast2700-intc-ic";
            reg = <0 0x12101b00 0 0x10>;
            #interrupt-cells = <2>;
            interrupt-controller;
            interrupts = <GIC_SPI 192 IRQ_TYPE_LEVEL_HIGH>,
                         <GIC_SPI 193 IRQ_TYPE_LEVEL_HIGH>,
                         <GIC_SPI 194 IRQ_TYPE_LEVEL_HIGH>,
                         <GIC_SPI 195 IRQ_TYPE_LEVEL_HIGH>,
                         <GIC_SPI 196 IRQ_TYPE_LEVEL_HIGH>,
                         <GIC_SPI 197 IRQ_TYPE_LEVEL_HIGH>;
        };
    }; 

New parent and child
    bus {
      #address-cells = <2>;
      #size-cells = <2>;

      intc0: interrupt-controller@12100000 {
        compatible = "aspeed,ast2700-intc0";
        reg = <0 0x12100000 0 0x4000>;
        ranges = <0x0 0x0 0x0 0x12100000 0x0 0x4000>;
        #address-cells = <2>;
        #size-cells = <2>;

        intc0_11: interrupt-controller@1b00 {
          compatible = "aspeed,ast2700-intc-ic";
          reg = <0 0x12101b00 0 0x10>;
          #interrupt-cells = <2>;
          interrupt-controller;
          interrupts = <GIC_SPI 192 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>,
                       <GIC_SPI 193 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>,
                       <GIC_SPI 194 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>,
                       <GIC_SPI 195 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>,
                       <GIC_SPI 196 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>,
                       <GIC_SPI 197 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>;
        };
      };

      intc1: interrupt-controller@14c18000 {
        compatible = "aspeed,ast2700-intc1";
        reg = <0 0x14c18000 0 0x400>;
        ranges = <0x0 0x0 0x0 0x14c18000 0x0 0x400>;
        #address-cells = <2>;
        #size-cells = <2>;

        intc1_0: interrupt-controller@100 {
          compatible = "aspeed,ast2700-intc-ic";
          reg = <0x0 0x100 0x0 0x10>;
          #interrupt-cells = <2>;
          interrupt-controller;
          interrupts-extended = <&intc0_11 0 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>;
        };
      };
    };

quoted

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
---
 .../aspeed,ast2700-intc.yaml                  | 158

+++++++++++++-----

quoted

 1 file changed, 115 insertions(+), 43 deletions(-)

diff --git
a/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast270
0-intc.yaml
b/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast270
0-intc.yaml index 55636d06a674..bdc4d8835843 100644
---
a/Documentation/devicetree/bindings/interrupt-controller/aspeed,ast270
0-intc.yaml

+++ b/Documentation/devicetree/bindings/interrupt-controller/aspeed,as
+++ t2700-intc.yaml

@@ -10,6 +10,33 @@ description:
   This interrupt controller hardware is second level interrupt controller

that

quoted

   is hooked to a parent interrupt controller. It's useful to combine multiple
   interrupt sources into 1 interrupt to parent interrupt controller.
+  Depend to which INTC0 or INTC1 used.
+  INTC0 and INTC1 are two kinds of interrupt controller with enable
+ and raw  status registers for use.
+  INTC0 is used to assert GIC if interrupt in INTC1 asserted.
+  INTC1 is used to assert INTC0 if interrupt of modules asserted.
+  +-----+   +---------+
+  | GIC |---|  INTC0  |
+  +-----+   +---------+
+            +---------+
+            |         |---module0
+            | INTC0_0 |---module1
+            |         |---...
+            +---------+---module31
+            |---....  |
+            +---------+
+            |         |     +---------+
+            | INTC0_11| +---| INTC1   |
+            |         |     +---------+
+            +---------+     +---------+---module0
+                            | INTC1_0 |---module1
+                            |         |---...
+                            +---------+---module31
+                            ...
+                            +---------+---module0
+                            | INTC1_5 |---module1
+                            |         |---...
+                            +---------+---module31

 maintainers:
   - Kevin Chen [off-list ref] @@ -17,49 +44,70 @@
maintainers:
 properties:
   compatible:
     enum:
-      - aspeed,ast2700-intc-ic
+      - aspeed,ast2700-intc0
+      - aspeed,ast2700-intc1

   reg:
     maxItems: 1

-  interrupt-controller: true
+  '#address-cells':
+    const: 2

-  '#interrupt-cells':
+  '#size-cells':
     const: 2
-    description:
-      The first cell is the IRQ number, the second cell is the trigger
-      type as defined in interrupt.txt in this directory.
-
-  interrupts:
-    maxItems: 6
-    description: |
-      Depend to which INTC0 or INTC1 used.
-      INTC0 and INTC1 are two kinds of interrupt controller with enable

and raw

quoted

-      status registers for use.
-      INTC0 is used to assert GIC if interrupt in INTC1 asserted.
-      INTC1 is used to assert INTC0 if interrupt of modules asserted.
-      +-----+   +-------+     +---------+---module0
-      | GIC |---| INTC0 |--+--| INTC1_0 |---module2
-      |     |   |       |  |  |         |---...
-      +-----+   +-------+  |  +---------+---module31
-                           |
-                           |   +---------+---module0
-                           +---| INTC1_1 |---module2
-                           |   |         |---...
-                           |   +---------+---module31
-                          ...
-                           |   +---------+---module0
-                           +---| INTC1_5 |---module2
-                               |         |---...
-                               +---------+---module31

+  ranges: true
+
+patternProperties:
+  "^interrupt-controller@":
+    type: object
+    description: Interrupt group child nodes
+    additionalProperties: false
+
+    properties:
+      compatible:
+        enum:
+          - aspeed,ast2700-intc-ic
+
+      reg:
+        maxItems: 1
+
+      interrupt-controller: true
+
+      '#interrupt-cells':
+        const: 2
+        description: |

Don't need '|'.

quoted

+          The first cell is the IRQ number, the second cell is the trigger
+          type as defined in interrupt.txt in this directory.

Don't add links to legacy documents.

quoted

+
+      interrupts:
+        minItems: 1
+        maxItems: 6
+        description: |
+          The interrupts provided by this interrupt controller.
+
+      interrupts-extended:

Why do you have both interrupts and interrupts-extended? They are mutually
exclusive and both are auto-magically supported. The schemas only have to
document 'interrupts'.

quoted

+        minItems: 1
+        maxItems: 6
+        description: |
+          This property is required when defining a cascaded interrupt

controller

quoted

+          that is connected under another interrupt controller. It specifies

the

quoted

+          parent interrupt(s) in the upstream controller to which this

controller

quoted

+          is connected.
+
+    oneOf:
+      - required: [interrupts]
+      - required: [interrupts-extended]
+
+    required:
+      - compatible
+      - reg
+      - interrupt-controller
+      - '#interrupt-cells'

 required:
   - compatible
   - reg
-  - interrupt-controller
-  - '#interrupt-cells'
-  - interrupts

 additionalProperties: false

@@ -68,19 +116,43 @@ examples:
     #include <dt-bindings/interrupt-controller/arm-gic.h>

     bus {
+      #address-cells = <2>;
+      #size-cells = <2>;
+
+      intc0: interrupt-controller@12100000 {

This node isn't an interrupt-controller.

quoted

+        compatible = "aspeed,ast2700-intc0";
+        reg = <0 0x12100000 0 0x4000>;
+        ranges = <0x0 0x0 0x0 0x12100000 0x0 0x4000>;
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        intc0_11: interrupt-controller@1b00 {
+          compatible = "aspeed,ast2700-intc-ic";
+          reg = <0 0x12101b00 0 0x10>;
+          #interrupt-cells = <2>;
+          interrupt-controller;
+          interrupts = <GIC_SPI 192 (GIC_CPU_MASK_SIMPLE(4) |

IRQ_TYPE_LEVEL_HIGH)>,

quoted

+                       <GIC_SPI 193 (GIC_CPU_MASK_SIMPLE(4) |

IRQ_TYPE_LEVEL_HIGH)>,

quoted

+                       <GIC_SPI 194 (GIC_CPU_MASK_SIMPLE(4) |

IRQ_TYPE_LEVEL_HIGH)>,

quoted

+                       <GIC_SPI 195 (GIC_CPU_MASK_SIMPLE(4) |

IRQ_TYPE_LEVEL_HIGH)>,

quoted

+                       <GIC_SPI 196 (GIC_CPU_MASK_SIMPLE(4) |

IRQ_TYPE_LEVEL_HIGH)>,

quoted

+                       <GIC_SPI 197 (GIC_CPU_MASK_SIMPLE(4) |

IRQ_TYPE_LEVEL_HIGH)>;

quoted

+        };
+      };
+
+      intc1: interrupt-controller@14c18000 {
+        compatible = "aspeed,ast2700-intc1";
+        reg = <0 0x14c18000 0 0x400>;
+        ranges = <0x0 0x0 0x0 0x14c18000 0x0 0x400>;
         #address-cells = <2>;
         #size-cells = <2>;

-        interrupt-controller@12101b00 {
-            compatible = "aspeed,ast2700-intc-ic";
-            reg = <0 0x12101b00 0 0x10>;
-            #interrupt-cells = <2>;
-            interrupt-controller;
-            interrupts = <GIC_SPI 192 IRQ_TYPE_LEVEL_HIGH>,
-                         <GIC_SPI 193 IRQ_TYPE_LEVEL_HIGH>,
-                         <GIC_SPI 194 IRQ_TYPE_LEVEL_HIGH>,
-                         <GIC_SPI 195 IRQ_TYPE_LEVEL_HIGH>,
-                         <GIC_SPI 196 IRQ_TYPE_LEVEL_HIGH>,
-                         <GIC_SPI 197 IRQ_TYPE_LEVEL_HIGH>;
+        intc1_0: interrupt-controller@100 {
+          compatible = "aspeed,ast2700-intc-ic";
+          reg = <0x0 0x100 0x0 0x10>;
+          #interrupt-cells = <2>;
+          interrupt-controller;
+          interrupts-extended = <&intc0_11 0

(GIC_CPU_MASK_SIMPLE(4)

quoted

+ | IRQ_TYPE_LEVEL_HIGH)>;
         };
+      };
     };
--
2.34.1