Re: [PATCH v6 4/4] dt-bindings: timer: Add CLINT bindings

From: Palmer Dabbelt
Date: Tue Aug 04 2020 - 21:48:15 EST


On Fri, 24 Jul 2020 00:18:22 PDT (-0700), Anup Patel wrote:
We add DT bindings documentation for CLINT device.

Signed-off-by: Anup Patel <anup.patel@xxxxxxx>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
Tested-by: Emil Renner Berhing <kernel@xxxxxxxx>
---
.../bindings/timer/sifive,clint.yaml | 60 +++++++++++++++++++
1 file changed, 60 insertions(+)
create mode 100644 Documentation/devicetree/bindings/timer/sifive,clint.yaml

diff --git a/Documentation/devicetree/bindings/timer/sifive,clint.yaml b/Documentation/devicetree/bindings/timer/sifive,clint.yaml
new file mode 100644
index 000000000000..2a0e9cd9fbcf
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/sifive,clint.yaml
@@ -0,0 +1,60 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timer/sifive,clint.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive Core Local Interruptor
+
+maintainers:
+ - Palmer Dabbelt <palmer@xxxxxxxxxxx>
+ - Anup Patel <anup.patel@xxxxxxx>
+
+description:
+ SiFive (and other RISC-V) SOCs include an implementation of the SiFive
+ Core Local Interruptor (CLINT) for M-mode timer and M-mode inter-processor
+ interrupts. It directly connects to the timer and inter-processor interrupt
+ lines of various HARTs (or CPUs) so RISC-V per-HART (or per-CPU) local
+ interrupt controller is the parent interrupt controller for CLINT device.
+ The clock frequency of CLINT is specified via "timebase-frequency" DT
+ property of "/cpus" DT node. The "timebase-frequency" DT property is
+ described in Documentation/devicetree/bindings/riscv/cpus.yaml
+
+properties:
+ compatible:
+ items:
+ - const: sifive,fu540-c000-clint
+ - const: sifive,clint0
+
+ description:
+ Should be "sifive,<chip>-clint" and "sifive,clint<version>".
+ Supported compatible strings are -
+ "sifive,fu540-c000-clint" for the SiFive CLINT v0 as integrated
+ onto the SiFive FU540 chip, and "sifive,clint0" for the SiFive
+ CLINT v0 IP block with no chip integration tweaks.
+ Please refer to sifive-blocks-ip-versioning.txt for details

Perfect! I was going to mention that we forgot to define the
"sifive,${name}${version}" scheme but I guess I just forgot that we did define
it ;)

+
+ reg:
+ maxItems: 1
+
+ interrupts-extended:
+ minItems: 1
+
+additionalProperties: false
+
+required:
+ - compatible
+ - reg
+ - interrupts-extended
+
+examples:
+ - |
+ timer@2000000 {
+ compatible = "sifive,fu540-c000-clint", "sifive,clint0";
+ interrupts-extended = <&cpu1intc 3 &cpu1intc 7
+ &cpu2intc 3 &cpu2intc 7
+ &cpu3intc 3 &cpu3intc 7
+ &cpu4intc 3 &cpu4intc 7>;
+ reg = <0x2000000 0x10000>;
+ };
+...

Reviewed-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>