commit d21f528156b17c9e069bfb4e215d7e399c94795b
author Haixia Shi <hshi@chromium.org> Mon Oct 05 14:35:09 2015 -0700
committer Haixia Shi <hshi@chromium.org> Wed Oct 07 16:03:10 2015 -0700
tree 3774d9aa41472d237df92583a07feefcbae47ba6
parent c9d98e57d47177b8ce1b5eff8e8f490e9bdbc16f

drm_hwcomposer: support virtual displays

Virtual display support is mandatory for HWC version 1.4.

As a minimal implementation, we use frambuffer target and let SF take care of
GLES composition. We still need to handle the acquire and release fences for
both the virtual display and all layers in a separate worker thread.

BUG=24609829
TEST=screen casting to chromecast

Change-Id: Idb962f4b5bb852c9ec9ebcaa1679a653c01737fb

hwcomposer.cpp

diff --git a/hwcomposer.cpp b/hwcomposer.cpp
index 3035362..a7c9e43 100644
--- a/hwcomposer.cpp
+++ b/hwcomposer.cpp
@@ -20,6 +20,7 @@
 #include "drm_hwcomposer.h"
 #include "drmresources.h"
 #include "importer.h"
+#include "virtualcompositorworker.h"
 #include "vsyncworker.h"
 
 #include <stdlib.h>
@@ -133,6 +134,7 @@
   }
 
   ~hwc_context_t() {
+    virtual_compositor_worker.Exit();
     delete importer;
   }
 
@@ -145,6 +147,7 @@
   const gralloc_module_t *gralloc;
   DummySwSyncTimeline dummy_timeline;
   bool use_framebuffer_target;
+  VirtualCompositorWorker virtual_compositor_worker;
 };
 
 static native_handle_t *dup_buffer_handle(buffer_handle_t handle) {
@@ -346,17 +349,22 @@
     if (!display_contents[i])
       continue;
 
-    DrmCrtc *crtc = ctx->drm.GetCrtcForDisplay(i);
-    if (!crtc) {
-      ALOGE("No crtc for display %d", i);
-      return -ENODEV;
+    bool use_framebuffer_target = ctx->use_framebuffer_target;
+    if (i == HWC_DISPLAY_VIRTUAL) {
+      use_framebuffer_target = true;
+    } else {
+      DrmCrtc *crtc = ctx->drm.GetCrtcForDisplay(i);
+      if (!crtc) {
+        ALOGE("No crtc for display %d", i);
+        return -ENODEV;
+      }
     }
 
     int num_layers = display_contents[i]->numHwLayers;
     for (int j = 0; j < num_layers; j++) {
       hwc_layer_1_t *layer = &display_contents[i]->hwLayers[j];
 
-      if (!ctx->use_framebuffer_target) {
+      if (!use_framebuffer_target) {
         if (layer->compositionType == HWC_FRAMEBUFFER)
           layer->compositionType = HWC_OVERLAY;
       } else {
@@ -415,6 +423,11 @@
     if (!sf_display_contents[i])
       continue;
 
+    if (i == HWC_DISPLAY_VIRTUAL) {
+      ctx->virtual_compositor_worker.QueueComposite(dc);
+      continue;
+    }
+
     std::ostringstream display_index_formatter;
     display_index_formatter << "retire fence for display " << i;
     std::string display_fence_description(display_index_formatter.str());
@@ -576,7 +589,7 @@
       *value = 1000 * 1000 * 1000 / 60;
       break;
     case HWC_DISPLAY_TYPES_SUPPORTED:
-      *value = HWC_DISPLAY_PRIMARY | HWC_DISPLAY_EXTERNAL;
+      *value = HWC_DISPLAY_PRIMARY | HWC_DISPLAY_EXTERNAL | HWC_DISPLAY_VIRTUAL;
       break;
   }
   return 0;
@@ -789,6 +802,11 @@
     }
   }
 
+  ret = ctx->virtual_compositor_worker.Init();
+  if (ret) {
+    ALOGE("Failed to initialize virtual compositor worker");
+    return ret;
+  }
   return 0;
 }