xref: /linux/Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml (revision 05d32474ab547fb097cfe3f3eb00a2aa7cdf4067)
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