xref: /freebsd-src/sys/contrib/device-tree/Bindings/rtc/amlogic,meson-vrtc.yaml (revision cb7aa33ac6cd46a5434798e50363136e64f3ae98)

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/rtc/amlogic,meson-vrtc.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Amlogic Virtual RTC (VRTC)

maintainers:
  - Neil Armstrong <neil.armstrong@linaro.org>

description: |
  This is a Linux interface to an RTC managed by firmware, hence it's
  virtual from a Linux perspective.  The interface is 1 register where
  an alarm time (in seconds) is to be written.
  The alarm register is a simple scratch register shared between the
  application processors (AP) and the secure co-processor (SCP.)  When
  the AP suspends, the SCP will use the value of this register to
  program an always-on timer before going sleep. When the timer expires,
  the SCP will wake up and will then wake the AP.

allOf:
  - $ref: rtc.yaml#

properties:
  compatible:
    enum:
      - amlogic,meson-vrtc

  reg:
    maxItems: 1

required:
  - compatible
  - reg

additionalProperties: false

examples:
  - |
    rtc@a8 {
      compatible = "amlogic,meson-vrtc";
      reg = <0x000a8 0x4>;
    };