diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/devicetree/bindings/interrupt-controller/riscv,cpu-intc.txt | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/Documentation/devicetree/bindings/interrupt-controller/riscv,cpu-intc.txt b/Documentation/devicetree/bindings/interrupt-controller/riscv,cpu-intc.txt index b0a8af51c388..265b223cd978 100644 --- a/Documentation/devicetree/bindings/interrupt-controller/riscv,cpu-intc.txt +++ b/Documentation/devicetree/bindings/interrupt-controller/riscv,cpu-intc.txt @@ -11,7 +11,7 @@ The RISC-V supervisor ISA manual specifies three interrupt sources that are attached to every HLIC: 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 -controller via Supervisor Binary Interface (SBI) calls and CSR reads. External +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). @@ -25,7 +25,15 @@ in the system. Required properties: - compatible : "riscv,cpu-intc" -- #interrupt-cells : should be <1> +- #interrupt-cells : should be <1>. 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. - interrupt-controller : Identifies the node as an interrupt controller Furthermore, this interrupt-controller MUST be embedded inside the cpu @@ -38,7 +46,7 @@ An example device tree entry for a HLIC is show below. ... cpu1-intc: interrupt-controller { #interrupt-cells = <1>; - compatible = "riscv,cpu-intc", "sifive,fu540-c000-cpu-intc"; + compatible = "sifive,fu540-c000-cpu-intc", "riscv,cpu-intc"; interrupt-controller; }; }; |