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Diffstat (limited to 'Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt')
-rw-r--r-- | Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt b/Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt new file mode 100644 index 000000000..c014f54a9 --- /dev/null +++ b/Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt @@ -0,0 +1,22 @@ +* Amlogic Virtual RTC (VRTC) + +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. + +Required properties: +- compatible: should be "amlogic,meson-vrtc" +- reg: physical address for the alarm register + +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. + +Example: + + vrtc: rtc@0a8 { + compatible = "amlogic,meson-vrtc"; + reg = <0x0 0x000a8 0x0 0x4>; + }; |