dt-bindings: riscv: convert cpu binding to json-schema

At Rob's request, we're starting to migrate our DT binding
documentation to json-schema YAML format.  Start by converting our cpu
binding documentation.  While doing so, document more properties and
nodes.  This includes adding binding documentation support for the E51
and U54 CPU cores ("harts") that are present on this SoC.  These cores
are described in:

    https://static.dev.sifive.com/FU540-C000-v1.0.pdf

This cpus.yaml file is intended to be a starting point and to
evolve over time.  It passes dt-doc-validate as of the yaml-bindings
commit 4c79d42e9216.

This patch was originally based on the ARM json-schema binding
documentation as added by commit 672951cbd1 ("dt-bindings: arm: Convert
cpu binding to json-schema").

Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
This commit is contained in:
Paul Walmsley 2019-05-20 09:19:40 -07:00
parent c7af559817
commit 4fd669a8c4

View File

@ -0,0 +1,168 @@
# SPDX-License-Identifier: (GPL-2.0 OR MIT)
%YAML 1.2
---
$id: http://devicetree.org/schemas/riscv/cpus.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: RISC-V bindings for 'cpus' DT nodes
maintainers:
- Paul Walmsley <paul.walmsley@sifive.com>
- Palmer Dabbelt <palmer@sifive.com>
allOf:
- $ref: /schemas/cpus.yaml#
properties:
$nodename:
const: cpus
description: Container of cpu nodes
'#address-cells':
const: 1
description: |
A single unsigned 32-bit integer uniquely identifies each RISC-V
hart in a system. (See the "reg" node under the "cpu" node,
below).
'#size-cells':
const: 0
patternProperties:
'^cpu@[0-9a-f]+$':
properties:
compatible:
type: array
items:
- enum:
- sifive,rocket0
- sifive,e5
- sifive,e51
- sifive,u54-mc
- sifive,u54
- sifive,u5
- const: riscv
description:
Identifies that the hart uses the RISC-V instruction set
and identifies the type of the hart.
mmu-type:
allOf:
- $ref: "/schemas/types.yaml#/definitions/string"
- enum:
- riscv,sv32
- riscv,sv39
- riscv,sv48
description:
Identifies the MMU address translation mode used on this
hart. These values originate from the RISC-V Privileged
Specification document, available from
https://riscv.org/specifications/
riscv,isa:
allOf:
- $ref: "/schemas/types.yaml#/definitions/string"
- enum:
- rv64imac
- rv64imafdc
description:
Identifies the specific RISC-V instruction set architecture
supported by the hart. These are documented in the RISC-V
User-Level ISA document, available from
https://riscv.org/specifications/
timebase-frequency:
type: integer
minimum: 1
description:
Specifies the clock frequency of the system timer in Hz.
This value is common to all harts on a single system image.
interrupt-controller:
type: object
description: Describes the CPU's local interrupt controller
properties:
'#interrupt-cells':
const: 1
compatible:
const: riscv,cpu-intc
interrupt-controller: true
required:
- '#interrupt-cells'
- compatible
- interrupt-controller
required:
- riscv,isa
- timebase-frequency
- interrupt-controller
examples:
- |
// Example 1: SiFive Freedom U540G Development Kit
cpus {
#address-cells = <1>;
#size-cells = <0>;
timebase-frequency = <1000000>;
cpu@0 {
clock-frequency = <0>;
compatible = "sifive,rocket0", "riscv";
device_type = "cpu";
i-cache-block-size = <64>;
i-cache-sets = <128>;
i-cache-size = <16384>;
reg = <0>;
riscv,isa = "rv64imac";
cpu_intc0: interrupt-controller {
#interrupt-cells = <1>;
compatible = "riscv,cpu-intc";
interrupt-controller;
};
};
cpu@1 {
clock-frequency = <0>;
compatible = "sifive,rocket0", "riscv";
d-cache-block-size = <64>;
d-cache-sets = <64>;
d-cache-size = <32768>;
d-tlb-sets = <1>;
d-tlb-size = <32>;
device_type = "cpu";
i-cache-block-size = <64>;
i-cache-sets = <64>;
i-cache-size = <32768>;
i-tlb-sets = <1>;
i-tlb-size = <32>;
mmu-type = "riscv,sv39";
reg = <1>;
riscv,isa = "rv64imafdc";
tlb-split;
cpu_intc1: interrupt-controller {
#interrupt-cells = <1>;
compatible = "riscv,cpu-intc";
interrupt-controller;
};
};
};
- |
// Example 2: Spike ISA Simulator with 1 Hart
cpus {
cpu@0 {
device_type = "cpu";
reg = <0>;
compatible = "riscv";
riscv,isa = "rv64imafdc";
mmu-type = "riscv,sv48";
interrupt-controller {
#interrupt-cells = <1>;
interrupt-controller;
compatible = "riscv,cpu-intc";
};
};
};
...