[PATCH v14 14/18] dt-bindings: interrupt-controller: Add RISC-V advanced PLIC

Anup Patel
2024-02-22T09:42:10Z

Add DT bindings document for RISC-V advanced platform level interrupt
controller (APLIC) defined by the RISC-V advanced interrupt architecture
(AIA) specification.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
---
.../interrupt-controller/riscv,aplic.yaml | 172 ++++++++++++++++++
1 file changed, 172 insertions(+)
create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,aplic.yaml

diff --git a/Documentation/devicetree/bindings/interrupt-controller/riscv,aplic.yaml b/Documentation/devicetree/bindings/interrupt-controller/riscv,aplic.yaml
new file mode 100644
index 000000000000..190a6499c932
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/riscv,aplic.yaml
@@ -0,0 +1,172 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/riscv,aplic.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V Advanced Platform Level Interrupt Controller (APLIC)
+
+maintainers:
+ - Anup Patel <anup@brainfault.org>
+
+description:
+ The RISC-V advanced interrupt architecture (AIA) defines an advanced
+ platform level interrupt controller (APLIC) for handling wired interrupts
+ in a RISC-V platform. The RISC-V AIA specification can be found at
+ https://github.com/riscv/riscv-aia.
+
+ The RISC-V APLIC is implemented as hierarchical APLIC domains where all
+ interrupt sources connect to the root APLIC domain and a parent APLIC
+ domain can delegate interrupt sources to it's child APLIC domains. There
+ is one device tree node for each APLIC domain.
+
+allOf:
+ - $ref: /schemas/interrupt-controller.yaml#
+
+properties:
+ compatible:
+ items:
+ - enum:
+ - qemu,aplic
+ - const: riscv,aplic
+
+ reg:
+ maxItems: 1
+
+ interrupt-controller: true
+
+ "#interrupt-cells":
+ const: 2
+
+ interrupts-extended:
+ minItems: 1
+ maxItems: 16384
+ description:
+ Given APLIC domain directly injects external interrupts to a set of
+ RISC-V HARTS (or CPUs). Each node pointed to should be a riscv,cpu-intc
+ node, which has a CPU node (i.e. RISC-V HART) as parent.
+
+ msi-parent:
+ description:
+ Given APLIC domain forwards wired interrupts as MSIs to a AIA incoming
+ message signaled interrupt controller (IMSIC). If both "msi-parent" and
+ "interrupts-extended" properties are present then it means the APLIC
+ domain supports both MSI mode and Direct mode in HW. In this case, the
+ APLIC driver has to choose between MSI mode or Direct mode.
+
+ riscv,num-sources:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ minimum: 1
+ maximum: 1023
+ description:
+ Specifies the number of wired interrupt sources supported by this
+ APLIC domain.
+
+ riscv,children:
+ $ref: /schemas/types.yaml#/definitions/phandle-array
+ minItems: 1
+ maxItems: 1024
+ items:
+ maxItems: 1
+ description:
+ A list of child APLIC domains for the given APLIC domain. Each child
+ APLIC domain is assigned a child index in increasing order, with the
+ first child APLIC domain assigned child index 0. The APLIC domain child
+ index is used by firmware to delegate interrupts from the given APLIC
+ domain to a particular child APLIC domain.
+
+ riscv,delegation:
+ $ref: /schemas/types.yaml#/definitions/phandle-array
+ minItems: 1
+ maxItems: 1024
+ items:
+ items:
+ - description: child APLIC domain phandle
+ - description: first interrupt number of the parent APLIC domain (inclusive)
+ - description: last interrupt number of the parent APLIC domain (inclusive)
+ description:
+ A interrupt delegation list where each entry is a triple consisting
+ of child APLIC domain phandle, first interrupt number of the parent
+ APLIC domain, and last interrupt number of the parent APLIC domain.
+ Firmware must configure interrupt delegation registers based on
+ interrupt delegation list.
+
+dependencies:
+ riscv,delegation: [ "riscv,children" ]
+
+required:
+ - compatible
+ - reg
+ - interrupt-controller
+ - "#interrupt-cells"
+ - riscv,num-sources
+
+anyOf:
+ - required:
+ - interrupts-extended
+ - required:
+ - msi-parent
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ // Example 1 (APLIC domains directly injecting interrupt to HARTs):
+
+ interrupt-controller@c000000 {
+ compatible = "qemu,aplic", "riscv,aplic";
+ interrupts-extended = <&cpu1_intc 11>,
+ <&cpu2_intc 11>,
+ <&cpu3_intc 11>,
+ <&cpu4_intc 11>;
+ reg = <0xc000000 0x4080>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ riscv,num-sources = <63>;
+ riscv,children = <&aplic1>, <&aplic2>;
+ riscv,delegation = <&aplic1 1 63>;
+ };
+
+ aplic1: interrupt-controller@d000000 {
+ compatible = "qemu,aplic", "riscv,aplic";
+ interrupts-extended = <&cpu1_intc 9>,
+ <&cpu2_intc 9>;
+ reg = <0xd000000 0x4080>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ riscv,num-sources = <63>;
+ };
+
+ aplic2: interrupt-controller@e000000 {
+ compatible = "qemu,aplic", "riscv,aplic";
+ interrupts-extended = <&cpu3_intc 9>,
+ <&cpu4_intc 9>;
+ reg = <0xe000000 0x4080>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ riscv,num-sources = <63>;
+ };
+
+ - |
+ // Example 2 (APLIC domains forwarding interrupts as MSIs):
+
+ interrupt-controller@c000000 {
+ compatible = "qemu,aplic", "riscv,aplic";
+ msi-parent = <&imsic_mlevel>;
+ reg = <0xc000000 0x4000>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ riscv,num-sources = <63>;
+ riscv,children = <&aplic3>;
+ riscv,delegation = <&aplic3 1 63>;
+ };
+
+ aplic3: interrupt-controller@d000000 {
+ compatible = "qemu,aplic", "riscv,aplic";
+ msi-parent = <&imsic_slevel>;
+ reg = <0xd000000 0x4000>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ riscv,num-sources = <63>;
+ };
+...
--
2.34.1