[v4,07/10] dt-bindings: interrupt-controller: Add RISC-V advanced PLIC

Message ID 20230613153415.350528-8-apatel@ventanamicro.com
State New
Headers
Series Linux RISC-V AIA Support |

Commit Message

Anup Patel June 13, 2023, 3:34 p.m. UTC
  We 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>
---
 .../interrupt-controller/riscv,aplic.yaml     | 169 ++++++++++++++++++
 1 file changed, 169 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,aplic.yaml
  

Comments

Conor Dooley June 14, 2023, 7:27 p.m. UTC | #1
Hey Anup,

Mostly looks good, once minor comment.

On Tue, Jun 13, 2023 at 09:04:12PM +0530, Anup Patel wrote:

> +  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.
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupt-controller
> +  - "#interrupt-cells"
> +  - riscv,num-sources
> +
> +anyOf:
> +  - required:
> +      - interrupts-extended
> +  - required:
> +      - msi-parent

Not sure if you missed this from the last version, but I asked if we
needed a
	dependencies:
	  riscv,delegate: [ riscv,children ]

IOW, I don't think it is valid to have a delegation without having
children?

Otherwise,
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>

Cheers,
Conor.
  
Anup Patel June 15, 2023, 5:47 a.m. UTC | #2
On Thu, Jun 15, 2023 at 12:57 AM Conor Dooley <conor@kernel.org> wrote:
>
> Hey Anup,
>
> Mostly looks good, once minor comment.
>
> On Tue, Jun 13, 2023 at 09:04:12PM +0530, Anup Patel wrote:
>
> > +  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.
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - interrupt-controller
> > +  - "#interrupt-cells"
> > +  - riscv,num-sources
> > +
> > +anyOf:
> > +  - required:
> > +      - interrupts-extended
> > +  - required:
> > +      - msi-parent
>
> Not sure if you missed this from the last version, but I asked if we
> needed a
>         dependencies:
>           riscv,delegate: [ riscv,children ]
>
> IOW, I don't think it is valid to have a delegation without having
> children?

Ahh, yes. I missed this one. I will update in the next revision.

>
> Otherwise,
> Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
>
> Cheers,
> Conor.

Regards,
Anup
  

Patch

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..e21de99b10a2
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/riscv,aplic.yaml
@@ -0,0 +1,169 @@ 
+# 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.
+
+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>;
+    };
+...