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, 3 deletions

diff --git a/android/hw-pipe-net.c b/android/hw-pipe-net.c
index dd8c8b1..8b8017d 100644
--- a/android/hw-pipe-net.c
+++ b/android/hw-pipe-net.c
@@ -23,6 +23,7 @@
 #include "android/utils/panic.h"
 #include "android/utils/system.h"
 #include "android/async-utils.h"
+#include "android/opengles.h"
 #include "android/looper.h"
 #include "hw/goldfish_pipe.h"
 
@@ -454,7 +455,11 @@ static const GoldfishPipeFuncs  netPipeUnix_funcs = {
 };
 #endif
 
-#define DEFAULT_OPENGLES_PORT  22468
+/* This is set to 1 in android_init_opengles() below, and tested
+ * by openglesPipe_init() to refuse a pipe connection if the function
+ * was never called.
+ */
+static int  _opengles_init;
 
 static void*
 openglesPipe_init( void* hwpipe, void* _looper, const char* args )
@@ -462,8 +467,15 @@ openglesPipe_init( void* hwpipe, void* _looper, const char* args )
     char temp[32];
     NetPipe *pipe;
 
+    if (!_opengles_init) {
+        /* This should never happen, unless there is a bug in the
+         * emulator's initialization, or the system image. */
+        D("Trying to open the OpenGLES pipe without GPU emulation!");
+        return NULL;
+    }
+
     /* For now, simply connect through tcp */
-    snprintf(temp, sizeof temp, "%d", DEFAULT_OPENGLES_PORT);
+    snprintf(temp, sizeof temp, "%d", ANDROID_OPENGLES_BASE_PORT);
     pipe = (NetPipe *)netPipe_initTcp(hwpipe, _looper, temp);
 
     if (pipe != NULL) {
@@ -496,7 +508,6 @@ static const GoldfishPipeFuncs  openglesPipe_funcs = {
     netPipe_wakeOn,
 };
 
-
 void
 android_net_pipes_init(void)
 {
@@ -508,3 +519,13 @@ android_net_pipes_init(void)
 #endif
     goldfish_pipe_add_type( "opengles", looper, &openglesPipe_funcs );
 }
+
+int
+android_init_opengles_pipes(void)
+{
+    /* TODO: Check that we can load and initialize the host emulation
+     *        libraries, and return -1 in case of error.
+     */
+    _opengles_init = 1;
+    return 0;
+}