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diff --git a/Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml b/Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml new file mode 100644 index 000000000..99e01f4d0 --- /dev/null +++ b/Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml @@ -0,0 +1,170 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +# Copyright (C) 2020 SiFive, Inc. +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/interrupt-controller/sifive,plic-1.0.0.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: SiFive Platform-Level Interrupt Controller (PLIC) + +description: + SiFive SoCs and other RISC-V SoCs include an implementation of the + Platform-Level Interrupt Controller (PLIC) high-level specification in + the RISC-V Privileged Architecture specification. The PLIC connects all + external interrupts in the system to all hart contexts in the system, via + the external interrupt source in each hart. + + A hart context is a privilege mode in a hardware execution thread. For example, + in an 4 core system with 2-way SMT, you have 8 harts and probably at least two + privilege modes per hart; machine mode and supervisor mode. + + Each interrupt can be enabled on per-context basis. Any context can claim + a pending enabled interrupt and then release it once it has been handled. + + Each interrupt has a configurable priority. Higher priority interrupts are + serviced first. Each context can specify a priority threshold. Interrupts + with priority below this threshold will not cause the PLIC to raise its + interrupt line leading to the context. + + The PLIC supports both edge-triggered and level-triggered interrupts. For + edge-triggered interrupts, the RISC-V PLIC spec allows two responses to edges + seen while an interrupt handler is active; the PLIC may either queue them or + ignore them. In the first case, handlers are oblivious to the trigger type, so + it is not included in the interrupt specifier. In the second case, software + needs to know the trigger type, so it can reorder the interrupt flow to avoid + missing interrupts. This special handling is needed by at least the Renesas + RZ/Five SoC (AX45MP AndesCore with a NCEPLIC100) and the T-HEAD C900 PLIC. + + While the RISC-V ISA doesn't specify a memory layout for the PLIC, the + "sifive,plic-1.0.0" device is a concrete implementation of the PLIC that + contains a specific memory layout, which is documented in chapter 8 of the + SiFive U5 Coreplex Series Manual <https://static.dev.sifive.com/U54-MC-RVCoreIP.pdf>. + + The thead,c900-plic is different from sifive,plic-1.0.0 in opensbi, the + T-HEAD PLIC implementation requires setting a delegation bit to allow access + from S-mode. So add thead,c900-plic to distinguish them. + +maintainers: + - Sagar Kadam <sagar.kadam@sifive.com> + - Paul Walmsley <paul.walmsley@sifive.com> + - Palmer Dabbelt <palmer@dabbelt.com> + +properties: + compatible: + oneOf: + - items: + - enum: + - renesas,r9a07g043-plic + - const: andestech,nceplic100 + - items: + - enum: + - sifive,fu540-c000-plic + - starfive,jh7100-plic + - canaan,k210-plic + - const: sifive,plic-1.0.0 + - items: + - enum: + - allwinner,sun20i-d1-plic + - const: thead,c900-plic + - items: + - const: sifive,plic-1.0.0 + - const: riscv,plic0 + deprecated: true + description: For the QEMU virt machine only + + reg: + maxItems: 1 + + '#address-cells': + const: 0 + + '#interrupt-cells': true + + interrupt-controller: true + + interrupts-extended: + minItems: 1 + maxItems: 15872 + description: + Specifies which contexts are connected to the PLIC, with "-1" specifying + that a context is not present. Each node pointed to should be a + riscv,cpu-intc node, which has a riscv node as parent. + + riscv,ndev: + $ref: "/schemas/types.yaml#/definitions/uint32" + description: + Specifies how many external interrupts are supported by this controller. + + clocks: true + + power-domains: true + + resets: true + +required: + - compatible + - '#address-cells' + - '#interrupt-cells' + - interrupt-controller + - reg + - interrupts-extended + - riscv,ndev + +allOf: + - if: + properties: + compatible: + contains: + enum: + - andestech,nceplic100 + - thead,c900-plic + + then: + properties: + '#interrupt-cells': + const: 2 + + else: + properties: + '#interrupt-cells': + const: 1 + + - if: + properties: + compatible: + contains: + const: renesas,r9a07g043-plic + + then: + properties: + clocks: + maxItems: 1 + + power-domains: + maxItems: 1 + + resets: + maxItems: 1 + + required: + - clocks + - power-domains + - resets + +additionalProperties: false + +examples: + - | + plic: interrupt-controller@c000000 { + #address-cells = <0>; + #interrupt-cells = <1>; + compatible = "sifive,fu540-c000-plic", "sifive,plic-1.0.0"; + interrupt-controller; + interrupts-extended = <&cpu0_intc 11>, + <&cpu1_intc 11>, <&cpu1_intc 9>, + <&cpu2_intc 11>, <&cpu2_intc 9>, + <&cpu3_intc 11>, <&cpu3_intc 9>, + <&cpu4_intc 11>, <&cpu4_intc 9>; + reg = <0xc000000 0x4000000>; + riscv,ndev = <10>; + }; |