1# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause 2# Copyright (C) 2020 SiFive, Inc. 3%YAML 1.2 4--- 5$id: http://devicetree.org/schemas/interrupt-controller/sifive,plic-1.0.0.yaml# 6$schema: http://devicetree.org/meta-schemas/core.yaml# 7 8title: SiFive Platform-Level Interrupt Controller (PLIC) 9 10description: 11 SiFive SoCs and other RISC-V SoCs include an implementation of the 12 Platform-Level Interrupt Controller (PLIC) high-level specification in 13 the RISC-V Privileged Architecture specification. The PLIC connects all 14 external interrupts in the system to all hart contexts in the system, via 15 the external interrupt source in each hart. 16 17 A hart context is a privilege mode in a hardware execution thread. For example, 18 in an 4 core system with 2-way SMT, you have 8 harts and probably at least two 19 privilege modes per hart; machine mode and supervisor mode. 20 21 Each interrupt can be enabled on per-context basis. Any context can claim 22 a pending enabled interrupt and then release it once it has been handled. 23 24 Each interrupt has a configurable priority. Higher priority interrupts are 25 serviced first. Each context can specify a priority threshold. Interrupts 26 with priority below this threshold will not cause the PLIC to raise its 27 interrupt line leading to the context. 28 29 The PLIC supports both edge-triggered and level-triggered interrupts. For 30 edge-triggered interrupts, the RISC-V PLIC spec allows two responses to edges 31 seen while an interrupt handler is active; the PLIC may either queue them or 32 ignore them. In the first case, handlers are oblivious to the trigger type, so 33 it is not included in the interrupt specifier. In the second case, software 34 needs to know the trigger type, so it can reorder the interrupt flow to avoid 35 missing interrupts. This special handling is needed by at least the Renesas 36 RZ/Five SoC (AX45MP AndesCore with a NCEPLIC100) and the T-HEAD C900 PLIC. 37 38 While the RISC-V ISA doesn't specify a memory layout for the PLIC, the 39 "sifive,plic-1.0.0" device is a concrete implementation of the PLIC that 40 contains a specific memory layout, which is documented in chapter 8 of the 41 SiFive U5 Coreplex Series Manual <https://static.dev.sifive.com/U54-MC-RVCoreIP.pdf>. 42 43 The thead,c900-plic is different from sifive,plic-1.0.0 in opensbi, the 44 T-HEAD PLIC implementation requires setting a delegation bit to allow access 45 from S-mode. So add thead,c900-plic to distinguish them. 46 47maintainers: 48 - Paul Walmsley <paul.walmsley@sifive.com> 49 - Palmer Dabbelt <palmer@dabbelt.com> 50 51properties: 52 compatible: 53 oneOf: 54 - items: 55 - enum: 56 - andestech,qilai-plic 57 - renesas,r9a07g043-plic 58 - const: andestech,nceplic100 59 - items: 60 - enum: 61 - anlogic,dr1v90-plic 62 - canaan,k210-plic 63 - eswin,eic7700-plic 64 - microchip,pic64gx-plic 65 - sifive,fu540-c000-plic 66 - spacemit,k1-plic 67 - starfive,jh7100-plic 68 - starfive,jh7110-plic 69 - tenstorrent,blackhole-plic 70 - const: sifive,plic-1.0.0 71 - items: 72 - enum: 73 - allwinner,sun20i-d1-plic 74 - sophgo,cv1800b-plic 75 - sophgo,cv1812h-plic 76 - sophgo,sg2000-plic 77 - sophgo,sg2002-plic 78 - sophgo,sg2042-plic 79 - sophgo,sg2044-plic 80 - thead,th1520-plic 81 - const: thead,c900-plic 82 - items: 83 - const: ultrarisc,dp1000-plic 84 - const: ultrarisc,cp100-plic 85 - items: 86 - const: sifive,plic-1.0.0 87 - const: riscv,plic0 88 deprecated: true 89 description: For the QEMU virt machine only 90 91 reg: 92 maxItems: 1 93 94 '#address-cells': 95 const: 0 96 97 '#interrupt-cells': true 98 99 interrupt-controller: true 100 101 interrupts-extended: 102 minItems: 1 103 maxItems: 15872 104 description: 105 Specifies which contexts are connected to the PLIC, with "-1" specifying 106 that a context is not present. Each node pointed to should be a 107 riscv,cpu-intc node, which has a riscv node as parent. 108 109 riscv,ndev: 110 $ref: /schemas/types.yaml#/definitions/uint32 111 description: 112 Specifies how many external (device) interrupts are supported by this 113 controller. Note that source 0 is reserved in PLIC, so the valid 114 interrupt sources are 1 to riscv,ndev inclusive. 115 116 clocks: true 117 118 power-domains: true 119 120 resets: true 121 122required: 123 - compatible 124 - '#address-cells' 125 - '#interrupt-cells' 126 - interrupt-controller 127 - reg 128 - interrupts-extended 129 - riscv,ndev 130 131allOf: 132 - if: 133 properties: 134 compatible: 135 contains: 136 enum: 137 - andestech,nceplic100 138 - thead,c900-plic 139 140 then: 141 properties: 142 '#interrupt-cells': 143 const: 2 144 145 else: 146 properties: 147 '#interrupt-cells': 148 const: 1 149 150 - if: 151 properties: 152 compatible: 153 contains: 154 const: renesas,r9a07g043-plic 155 156 then: 157 properties: 158 clocks: 159 maxItems: 1 160 161 power-domains: 162 maxItems: 1 163 164 resets: 165 maxItems: 1 166 167 required: 168 - clocks 169 - power-domains 170 - resets 171 172additionalProperties: false 173 174examples: 175 - | 176 plic: interrupt-controller@c000000 { 177 #address-cells = <0>; 178 #interrupt-cells = <1>; 179 compatible = "sifive,fu540-c000-plic", "sifive,plic-1.0.0"; 180 interrupt-controller; 181 interrupts-extended = <&cpu0_intc 11>, 182 <&cpu1_intc 11>, <&cpu1_intc 9>, 183 <&cpu2_intc 11>, <&cpu2_intc 9>, 184 <&cpu3_intc 11>, <&cpu3_intc 9>, 185 <&cpu4_intc 11>, <&cpu4_intc 9>; 186 reg = <0xc000000 0x4000000>; 187 riscv,ndev = <10>; 188 }; 189