commit ea7a01d1cda10e47dfa29eea9e0f49390cbaba79
author Saurabh Shah <saurshah@codeaurora.org> Thu May 22 17:45:36 2014 -0700
committer Saurabh Shah <saurshah@codeaurora.org> Tue Jun 10 13:41:01 2014 -0700
tree 50fbc3e48bf3ee7e95292d292ba08e74b697e651
parent 8f4e1a68ba5852b02a1810f9ceee735e59d669b2

hwc: Source Split layers always if indicated by driver

Source Split layers always if the driver indicates so by setting
the src_split_always in the capabilities sysfs node.
This is applicable to layers whose width > mixer's width, since
MDP clk rate is dependent on max(mixer_width, layer_width).

This feature can be enabled if the panel height is more than a
certain empirically derived value. Splitting always in those
cases can help with a lower voltage.

Change-Id: If9b33f11ca4132eb77416c26819f7473c65d3b08

libqdutils/mdp_version.cpp

diff --git a/libqdutils/mdp_version.cpp b/libqdutils/mdp_version.cpp
index 96ed4d2..bc63ddf 100644
--- a/libqdutils/mdp_version.cpp
+++ b/libqdutils/mdp_version.cpp
@@ -88,6 +88,7 @@
     mLowBw = 0;
     mHighBw = 0;
     mSourceSplit = false;
+    mSourceSplitAlways = false;
     mRGBHasNoScalar = false;
 
     updatePanelInfo();
@@ -306,6 +307,30 @@
         free(line);
         fclose(sysfsFd);
     }
+
+    if(mSourceSplit) {
+        memset(sysfsPath, 0, sizeof(sysfsPath));
+        snprintf(sysfsPath , sizeof(sysfsPath),
+                "/sys/class/graphics/fb0/msm_fb_src_split_info");
+
+        sysfsFd = fopen(sysfsPath, "rb");
+        if (sysfsFd == NULL) {
+            ALOGE("%s: Opening file %s failed with error %s", __FUNCTION__,
+                    sysfsPath, strerror(errno));
+            return false;
+        } else {
+            line = (char *) malloc(len);
+            if((read = getline(&line, &len, sysfsFd)) != -1) {
+                if(!strncmp(line, "src_split_always",
+                        strlen("src_split_always"))) {
+                    mSourceSplitAlways = true;
+                }
+            }
+            free(line);
+            fclose(sysfsFd);
+        }
+    }
+
     ALOGD_IF(DEBUG, "%s: mMDPVersion: %d mMdpRev: %x mRGBPipes:%d,"
                     "mVGPipes:%d", __FUNCTION__, mMDPVersion, mMdpRev,
                     mRGBPipes, mVGPipes);
@@ -371,6 +396,10 @@
     return mSourceSplit;
 }
 
+bool MDPVersion::isSrcSplitAlways() const {
+    return mSourceSplitAlways;
+}
+
 bool MDPVersion::isRGBScalarSupported() const {
     return (!mRGBHasNoScalar);
 }

libqdutils/mdp_version.h

diff --git a/libqdutils/mdp_version.h b/libqdutils/mdp_version.h
index e862d2d..8bb9c39 100644
--- a/libqdutils/mdp_version.h
+++ b/libqdutils/mdp_version.h
@@ -140,6 +140,7 @@
     unsigned long getLowBw() { return mLowBw; }
     unsigned long getHighBw() { return mHighBw; }
     bool isSrcSplit() const;
+    bool isSrcSplitAlways() const;
     bool isRGBScalarSupported() const;
     bool is8x26();
     bool is8x74v2();
@@ -170,6 +171,8 @@
     unsigned long mLowBw; //kbps
     unsigned long mHighBw; //kbps
     bool mSourceSplit;
+    //Additional property on top of source split
+    bool mSourceSplitAlways;
     bool mRGBHasNoScalar;
 };
 }; //namespace qdutils