| # 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: |
| - 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>; |
| }; |