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+# SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/riscv,cpu-intc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V Hart-Level Interrupt Controller (HLIC)
+
+description:
+ RISC-V cores include Control Status Registers (CSRs) which are local to
+ each CPU core (HART in RISC-V terminology) and can be read or written by
+ software. Some of these CSRs are used to control local interrupts connected
+ to the core. Every interrupt is ultimately routed through a hart's HLIC
+ before it interrupts that hart.
+
+ The RISC-V supervisor ISA manual specifies three interrupt sources that are
+ attached to every HLIC namely software interrupts, the timer interrupt, and
+ external interrupts. Software interrupts are used to send IPIs between
+ cores. The timer interrupt comes from an architecturally mandated real-
+ time timer that is controlled via Supervisor Binary Interface (SBI) calls
+ and CSR reads. External interrupts connect all other device interrupts to
+ the HLIC, which are routed via the platform-level interrupt controller
+ (PLIC).
+
+ All RISC-V systems that conform to the supervisor ISA specification are
+ required to have a HLIC with these three interrupt sources present. Since
+ the interrupt map is defined by the ISA it's not listed in the HLIC's device
+ tree entry, though external interrupt controllers (like the PLIC, for
+ example) will need to define how their interrupts map to the relevant HLICs.
+ This means a PLIC interrupt property will typically list the HLICs for all
+ present HARTs in the system.
+
+maintainers:
+ - Palmer Dabbelt <palmer@dabbelt.com>
+ - Paul Walmsley <paul.walmsley@sifive.com>
+
+properties:
+ compatible:
+ oneOf:
+ - items:
+ - const: andestech,cpu-intc
+ - const: riscv,cpu-intc
+ - const: riscv,cpu-intc
+
+ interrupt-controller: true
+
+ '#interrupt-cells':
+ const: 1
+ description: |
+ The interrupt sources are defined by the RISC-V supervisor ISA manual,
+ with only the following three interrupts being defined for
+ supervisor mode:
+ - Source 1 is the supervisor software interrupt, which can be sent by
+ an SBI call and is reserved for use by software.
+ - Source 5 is the supervisor timer interrupt, which can be configured
+ by SBI calls and implements a one-shot timer.
+ - Source 9 is the supervisor external interrupt, which chains to all
+ other device interrupts.
+
+required:
+ - compatible
+ - '#interrupt-cells'
+ - interrupt-controller
+
+additionalProperties: false
+
+examples:
+ - |
+ interrupt-controller {
+ #interrupt-cells = <1>;
+ compatible = "riscv,cpu-intc";
+ interrupt-controller;
+ };