Add hw.gpu.enabled hardware property

This patch adds a new hardware property to enable GPU emulation
(named hw.gpu.enabled). It is currently disabled by default.

It also modifies the UI code to display the GL output properly
inside the UI window. And sets the kernel parameter qemu.gles
to either 0 or 1 to indicate to the guest system's GLES libraries
whether to use GPU emulation or fallback to the software renderer.

A future patch will also add auto-detection of desktop GL capabilities.
For example, if the emulator is started on a headless server without
an X11/GL display, hw.gpu.enabled will be forced to 'no', forcing the
guest to use the software renderer.

Another patch will allow to change the property from the command-line
for debugging purpose.

NOTE: If you want to test GPU emulation, change the default value of
      the property in android/avd/hardware-properties.ini from 'no'
      to 'yes'. You will need to run a ToT master AOSP tree with
      the following pending patches applied:

      https://review.source.android.com/25797
      https://review.source.android.com/25154
      https://review.source.android.com/25759

Change-Id: I1fa3512be24395244fd5068f2bf59ad54db5c7d5

1 files changed, 24 insertions, 0 deletions

diff --git a/vl-android.c b/vl-android.c
index 32b5eac..4c2a433 100644
--- a/vl-android.c
+++ b/vl-android.c
@@ -65,6 +65,7 @@
 #include "android/display-core.h"
 #include "android/utils/timezone.h"
 #include "android/snapshot.h"
+#include "android/opengles.h"
 #include "targphys.h"
 #include "tcpdump.h"
 
@@ -3813,6 +3814,29 @@ int main(int argc, char **argv, char **envp)
         nand_add_dev(tmp);
     }
 
+    /* qemu.gles will be read by the OpenGLES emulation libraries.
+    * If set to 0, the software GLES renderer will be used as a fallback.
+    * If the parameter is undefined, this means the system image runs
+    * inside an emulator that doesn't support GPU emulation at all.
+    */
+    {
+        int  gles_emul = 0;
+
+        if (android_hw->hw_gpu_enabled) {
+            if (android_initOpenglesEmulation() == 0) {
+                gles_emul = 1;
+                android_startOpenglesRenderer(android_hw->hw_lcd_width, android_hw->hw_lcd_height);
+            } else {
+                dwarning("Could not initialize OpenglES emulation, using software renderer.");
+            }
+        }
+        if (gles_emul) {
+            stralloc_add_str(kernel_params, " qemu.gles=1");
+        } else {
+            stralloc_add_str(kernel_params, " qemu.gles=0");
+        }
+    }
+
     /* We always force qemu=1 when running inside QEMU */
     stralloc_add_str(kernel_params, " qemu=1");