Revert "Exynos decoder: workaround for wrong MFC output format."

content/common/gpu/media/exynos_video_decode_accelerator.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <dlfcn.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <linux/videodev2.h>
 #include <poll.h>
 #include <sys/eventfd.h>
@@ skipping 380 matching lines @@
     DLOG(ERROR) << "Initialize(): ioctl() failed: VIDIOC_QUERYCAP"
         ", caps check failed: 0x" << std::hex << caps.capabilities;
     NOTIFY_ERROR(PLATFORM_FAILURE);
     return false;
   }
 
   if (!CreateMfcInputBuffers())
     return false;
 
   // MFC output format has to be setup before streaming starts.
-  // TODO(hshi): set format back to tiled (V4L2_PIX_FMT_NV12MT_16X16) when we
-  // fix the underlying driver/firmware issue. http://crbug.com/303300.
   struct v4l2_format format;
   memset(&format, 0, sizeof(format));
   format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
-  format.fmt.pix_mp.pixelformat = V4L2_PIX_FMT_NV12M;
+  format.fmt.pix_mp.pixelformat = V4L2_PIX_FMT_NV12MT_16X16;

[Ami GONE FROM CHROMIUM, 2013/10/28 15:03:41]

Does this improve perf? 
(why is NV12MT_16x16 better than NV12M?  IDK)

[sheu, 2013/10/28 17:24:49]

MT16x16 is a tiled format, and NV12M is plain linear.  We get about a 0.8% perf
improvement from this.  (Yes, I tested, and it's outside of run-to-run noise.)

   IOCTL_OR_ERROR_RETURN_FALSE(mfc_fd_, VIDIOC_S_FMT, &format);
 
   // Subscribe to the resolution change event.
   struct v4l2_event_subscription sub;
   memset(&sub, 0, sizeof(sub));
   sub.type = V4L2_EVENT_RESOLUTION_CHANGE;
   IOCTL_OR_ERROR_RETURN_FALSE(mfc_fd_, VIDIOC_SUBSCRIBE_EVENT, &sub);
 
   // Initialize format-specific bits.
   if (video_profile_ >= media::H264PROFILE_MIN &&
@@ skipping 1689 matching lines @@
 
 bool ExynosVideoDecodeAccelerator::CreateBuffersForFormat(
     const struct v4l2_format& format) {
   DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
   CHECK_EQ(format.fmt.pix_mp.num_planes, 2);
   frame_buffer_size_.SetSize(
       format.fmt.pix_mp.width, format.fmt.pix_mp.height);
   mfc_output_buffer_size_[0] = format.fmt.pix_mp.plane_fmt[0].sizeimage;
   mfc_output_buffer_size_[1] = format.fmt.pix_mp.plane_fmt[1].sizeimage;
   mfc_output_buffer_pixelformat_ = format.fmt.pix_mp.pixelformat;
-  DCHECK_EQ(mfc_output_buffer_pixelformat_, V4L2_PIX_FMT_NV12M);
+  DCHECK_EQ(mfc_output_buffer_pixelformat_, V4L2_PIX_FMT_NV12MT_16X16);
   DVLOG(3) << "CreateBuffersForFormat(): new resolution: "
            << frame_buffer_size_.ToString();
 
   if (!CreateMfcOutputBuffers() || !CreateGscInputBuffers() ||
       !CreateGscOutputBuffers())
     return false;
 
   return true;
 }
 
@@ skipping 388 matching lines @@
 
 void ExynosVideoDecodeAccelerator::PictureCleared() {
   DVLOG(3) << "PictureCleared(). clearing count=" << picture_clearing_count_;
   DCHECK_EQ(decoder_thread_.message_loop(), base::MessageLoop::current());
   DCHECK_GT(picture_clearing_count_, 0);
   picture_clearing_count_--;
   SendPictureReady();
 }
 
 }  // namespace content