Documentation/devicetree/bindings/timer/arm,sp804.yaml
Source file repositories/reference/linux-study-clean/Documentation/devicetree/bindings/timer/arm,sp804.yaml
File Facts
- System
- Linux kernel
- Corpus path
Documentation/devicetree/bindings/timer/arm,sp804.yaml- Extension
.yaml- Size
- 2893 bytes
- Lines
- 98
- Domain
- Support Tooling And Documentation
- Bucket
- Documentation
- Inferred role
- Support Tooling And Documentation: configuration, schema, or hardware description
- Status
- atlas-only
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
# SPDX-License-Identifier: GPL-2.0
%YAML 1.2
---
$id: http://devicetree.org/schemas/timer/arm,sp804.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: ARM sp804 Dual Timers
maintainers:
- Haojian Zhuang <haojian.zhuang@linaro.org>
description: |+
The Arm SP804 IP implements two independent timers, configurable for
16 or 32 bit operation and capable of running in one-shot, periodic, or
free-running mode. The input clock is shared, but can be gated and prescaled
independently for each timer.
There is a viriant of Arm SP804: Hisilicon 64-bit SP804 timer. Some Hisilicon
SoCs, such as Hi1212, should use the dedicated compatible: "hisilicon,sp804".
# Need a custom select here or 'arm,primecell' will match on lots of nodes
select:
properties:
compatible:
contains:
enum:
- arm,sp804
- hisilicon,sp804
required:
- compatible
properties:
compatible:
items:
- enum:
- arm,sp804
- hisilicon,sp804
- const: arm,primecell
interrupts:
description: |
If two interrupts are listed, those are the interrupts for timer
1 and 2, respectively. If there is only a single interrupt, it is
either a combined interrupt or the sole interrupt of one timer, as
specified by the "arm,sp804-has-irq" property.
minItems: 1
maxItems: 2
reg:
description: The physical base address of the SP804 IP.
maxItems: 1
clocks:
description: |
Clocks driving the dual timer hardware. This list should
be 1 or 3 clocks. With 3 clocks, the order is timer0 clock, timer1
clock, apb_pclk. A single clock can also be specified if the same
clock is used for all clock inputs.
oneOf:
- items:
- description: clock for timer 1
- description: clock for timer 2
- description: bus clock
- items:
- description: unified clock for both timers and the bus
clock-names: true
# The original binding did not specify any clock names, and there is no
# consistent naming used in the existing DTs. The primecell binding
# requires the "apb_pclk" name, so we need this property.
Annotation
- Atlas domain: Support Tooling And Documentation / Documentation.
- Implementation status: atlas-only.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.