drm/msm/sde: add shared display support

Add support to shared display for panel stacking and split screen
application.

The current DRM framework only allows one atomic commit for
each display, this change will create virtual display pipelines
based on the physical display pipeline, and each virtual display
can support independent async atomic commit.

With the change user mode application can setup and update
display on each virtual display and share the same physical port.
No mode switch is allowed on virtual display. When all virtual
displays are powered off,  the physical display will also power off.

Change-Id: Ibf9a7dd1a96c59b6db9891d826cb4f11b409696c
Signed-off-by: Xiaowen Wu <wxiaowen@codeaurora.org>
Signed-off-by: Rahul Sharma <rahsha@codeaurora.org>

1 files changed, 77 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/drm/msm/sde-shd.txt b/Documentation/devicetree/bindings/drm/msm/sde-shd.txt
new file mode 100644
index 000000000000..28bc831c46e6
--- /dev/null
+++ b/Documentation/devicetree/bindings/drm/msm/sde-shd.txt
@@ -0,0 +1,77 @@
+QTI Snapdragon Display Engine (SDE) shared display
+
+Required properties:
+- compatible:		"qcom,shared-display"
+- qcom,shared-display-base: node handle of qcom,shared-display-base, see below.
+- qcom,blend-stage-range: blend stage range that are not shared in one display
+- qcom,shared-display-src-mode: source resolution of the shared display, contains
+			two properties:
+			qcom,mode-h-active: horizontal resolution
+			qcom,mode-v-active: vertical resolution
+- qcom,shared-display-dst-mode: destination rectangle in the shared display,
+			contains 4 properties:
+			qcom,mode-x-offset: x offset inside the shared display
+			qcom,mode-y-offset: y offset inside the shared display
+			qcom,mode-width: width inside the shared display
+			qcom,mode-height: height inside the shared display
+
+
+qcom,shared-display-base properties:
+- qcom,shared-display-base-intf: intf index of the base display
+- qcom,shared-display-base-mst: if display is DP MST type, optional
+- qcom,shared-display-base-mode: timing of the base display, contains the
+			following properties:
+			qcom,mode-h-active: H active size
+			qcom,mode-h-front-porch: H front portch
+			qcom,mode-h-pulse-width: H pulse width
+			qcom,mode-h-back-porch: H back porch
+			qcom,mode-h-active-high: if H active polarity is high
+			qcom,mode-v-active: V active size
+			qcom,mode-v-front-porch: V front portch
+			qcom,mode-v-pulse-width: V pulse width
+			qcom,mode-v-back-porch: V back porch
+			qcom,mode-v-active-high: if V active polarity is high
+			qcom,mode-refresh-rate: vertial refresh rate
+			qcom,mode-clock-in-khz: clock in kHz
+
+Example:
+
+/ {
+	...
+
+	sde_sh_base0: qcom,shared-display-base@0 {
+		qcom,shared-display-base-intf = <0>;
+		qcom,shared-display-base-mst;
+		qcom,shared-display-base-mode {
+			qcom,mode-h-active = <3840>;
+			qcom,mode-h-front-porch = <176>;
+			qcom,mode-h-pulse-width = <88>;
+			qcom,mode-h-back-porch = <296>;
+			qcom,mode-h-active-high;
+			qcom,mode-v-active = <2160>;
+			qcom,mode-v-front-porch = <8>;
+			qcom,mode-v-pulse-width = <10>;
+			qcom,mode-v-back-porch = <72>;
+			qcom,mode-v-active-high;
+			qcom,mode-refresh-rate = <30>;
+			qcom,mode-clock-in-khz = <297000>;
+		};
+	};
+
+	sde_sh0: qcom,shared-display@0 {
+		compatible = "qcom,shared-display";
+		qcom,shared-display-base = <&sde_sh_base0>;
+		qcom,blend-stage-range = <0 5>;
+		qcom,shared-display-src-mode {
+			qcom,mode-h-active = <1920>;
+			qcom,mode-v-active = <1080>;
+		};
+		qcom,shared-display-dst-mode {
+			qcom,mode-x-offset = <0>;
+			qcom,mode-y-offset = <0>;
+			qcom,mode-width = <1920>;
+			qcom,mode-height = <1080>;
+		};
+	};
+
+};