overlay: Add support for decimation.

Add support for decimation on top of what MDP can downscale,
because decimation can have quality issues.
B-family MDP downscale of 1/4, plus decimation of 1/16 can let
us have a total downscale of 1/64.

Also decimate by 2 (min) if width is greater than what layer mixer
supports and is not handled by the client.

Change-Id: I3b7c4bf321c7561bd98206ad118f4ac1ee2879ae
diff --git a/libqdutils/mdp_version.h b/libqdutils/mdp_version.h
index 98de371..2fca640 100644
--- a/libqdutils/mdp_version.h
+++ b/libqdutils/mdp_version.h
@@ -52,6 +52,10 @@
     MDSS_V5     = 500,
 };
 
+enum {
+    MAX_DISPLAY_DIM = 2048,
+};
+
 #define MDDI_PANEL       '1'
 #define EBI2_PANEL       '2'
 #define LCDC_PANEL       '3'
@@ -76,6 +80,8 @@
     uint8_t getRGBPipes() { return mRGBPipes; }
     uint8_t getVGPipes() { return mVGPipes; }
     uint8_t getDMAPipes() { return mDMAPipes; }
+    bool supportsDecimation();
+    uint32_t getMaxMDPDownscale();
 private:
     int mMDPVersion;
     char mPanelType;
@@ -84,6 +90,8 @@
     uint8_t mRGBPipes;
     uint8_t mVGPipes;
     uint8_t mDMAPipes;
+    uint32_t mFeatures;
+    uint32_t mMDPDownscale;
 };
 }; //namespace qdutils
 #endif //INCLUDE_LIBQCOMUTILS_MDPVER