drm/tegra: Add eDP support

Add support for eDP functionality found on Tegra124 and later SoCs. Only
fast link training is currently supported.

Signed-off-by: Thierry Reding <treding@nvidia.com>

Documentation/devicetree/bindings/gpu/nvidia,tegra20-host1x.txt

@@ -190,6 +190,48 @@ of the following host1x client modules:
   - nvidia,edid: supplies a binary EDID blob
   - nvidia,panel: phandle of a display panel
 
+- sor: serial output resource
+
+  Required properties:
+  - compatible: "nvidia,tegra124-sor"
+  - reg: Physical base address and length of the controller's registers.
+  - interrupts: The interrupt outputs from the controller.
+  - clocks: Must contain an entry for each entry in clock-names.
+    See ../clocks/clock-bindings.txt for details.
+  - clock-names: Must include the following entries:
+    - sor: clock input for the SOR hardware
+    - parent: input for the pixel clock
+    - dp: reference clock for the SOR clock
+    - safe: safe reference for the SOR clock during power up
+  - resets: Must contain an entry for each entry in reset-names.
+    See ../reset/reset.txt for details.
+  - reset-names: Must include the following entries:
+    - sor
+
+  Optional properties:
+  - nvidia,ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing
+  - nvidia,hpd-gpio: specifies a GPIO used for hotplug detection
+  - nvidia,edid: supplies a binary EDID blob
+  - nvidia,panel: phandle of a display panel
+
+  Optional properties when driving an eDP output:
+  - nvidia,dpaux: phandle to a DispayPort AUX interface
+
+- dpaux: DisplayPort AUX interface
+  - compatible: "nvidia,tegra124-dpaux"
+  - reg: Physical base address and length of the controller's registers.
+  - interrupts: The interrupt outputs from the controller.
+  - clocks: Must contain an entry for each entry in clock-names.
+    See ../clocks/clock-bindings.txt for details.
+  - clock-names: Must include the following entries:
+    - dpaux: clock input for the DPAUX hardware
+    - parent: reference clock
+  - resets: Must contain an entry for each entry in reset-names.
+    See ../reset/reset.txt for details.
+  - reset-names: Must include the following entries:
+    - dpaux
+  - vdd-supply: phandle of a supply that powers the DisplayPort link
+
 Example:
 
 / {

drivers/gpu/drm/tegra/Makefile

@@ -11,6 +11,8 @@ tegra-drm-y := \
 	hdmi.o \
 	mipi-phy.o \
 	dsi.o \
+	sor.o \
+	dpaux.o \
 	gr2d.o \
 	gr3d.o
 

drivers/gpu/drm/tegra/dc.h

@@ -118,6 +118,7 @@
 #define DC_DISP_DISP_WIN_OPTIONS		0x402
 #define HDMI_ENABLE (1 << 30)
 #define DSI_ENABLE  (1 << 29)
+#define SOR_ENABLE  (1 << 25)
 
 #define DC_DISP_DISP_MEM_HIGH_PRIORITY		0x403
 #define CURSOR_THRESHOLD(x)   (((x) & 0x03) << 24)