1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/rtc/amlogic,meson-vrtc.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: Amlogic Virtual RTC (VRTC)
8
9maintainers:
10  - Neil Armstrong <neil.armstrong@linaro.org>
11
12description: |
13  This is a Linux interface to an RTC managed by firmware, hence it's
14  virtual from a Linux perspective.  The interface is 1 register where
15  an alarm time (in seconds) is to be written.
16  The alarm register is a simple scratch register shared between the
17  application processors (AP) and the secure co-processor (SCP.)  When
18  the AP suspends, the SCP will use the value of this register to
19  program an always-on timer before going sleep. When the timer expires,
20  the SCP will wake up and will then wake the AP.
21
22allOf:
23  - $ref: rtc.yaml#
24
25properties:
26  compatible:
27    enum:
28      - amlogic,meson-vrtc
29
30  reg:
31    maxItems: 1
32
33required:
34  - compatible
35  - reg
36
37additionalProperties: false
38
39examples:
40  - |
41    rtc@a8 {
42      compatible = "amlogic,meson-vrtc";
43      reg = <0x000a8 0x4>;
44    };
45