From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Hilman Subject: [PATCH v3 1/2] dt-bindings: rtc: new binding for Amlogic VRTC Date: Mon, 12 Aug 2019 16:28:49 -0700 Message-ID: <20190812232850.8016-2-khilman@kernel.org> References: <20190812232850.8016-1-khilman@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190812232850.8016-1-khilman@kernel.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Alexandre Belloni , linux-rtc@vger.kernel.org Cc: linux-amlogic@lists.infradead.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Neil Armstrong List-Id: devicetree@vger.kernel.org From: Kevin Hilman Add binding fo the new VRTC driver for Amlogic SoCs. The 64-bit family of SoCs only has an RTC managed by firmware, and this VRTC driver provides the simple, one-register firmware interface. Reviewed-by: Rob Herring Signed-off-by: Kevin Hilman --- .../bindings/rtc/rtc-meson-vrtc.txt | 22 +++++++++++++++++++ 1 file changed, 22 insertions(+) create mode 100644 Documentation/devicetree/bindings/rtc/rtc-meson-vrtc.txt 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 000000000000..c014f54a9853 --- /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>; + }; -- 2.22.0