tree 5ea4eaa89a60d68fdf7a5c296a8cb5ef30eeb81e
parent 35b7b4b8e662f8ddc6da9f5babe19e9cd78d7218
author Chad Versace <chadversary@chromium.org> 1479168831 -0800
committer Chad Versace <chadversary@chromium.org> 1504338385 -0700

anv: Implement VK_ANDROID_native_buffer

This implementation is correct (afaict), but takes two shortcuts
regarding the import/export of Android sync fds.

  Shortcut 1. When Android calls vkAcquireImageANDROID to import a sync
  fd into a VkSemaphore or VkFence, the driver instead simply blocks on
  the sync fd, then puts the VkSemaphore or VkFence into the signalled
  state. Thanks to implicit sync, this produces correct behavior (with
  extra latency overhead, perhaps) despite its ugliness.

  Shortcut 2. When Android calls vkQueueSignalReleaseImageANDROID to export
  a collection of wait semaphores as a sync fd, the driver instead
  submits the semaphores to the queue, then returns sync fd -1, which
  informs the caller that no additional synchronization is needed.
  Again, thanks to implicit sync, this produces correct behavior (with
  extra batch submission overhead) despite its ugliness.

I chose to take the shortcuts instead of properly importing/exporting
the sync fds for two reasons:

  Reason 1. I've already tested this patch with dEQP and with demos
  apps. It works. I wanted to get the tested patches into the tree now,
  and polish the implementation afterwards.

  Reason 2. I want to run this on a 3.18 kernel (gasp!). In 3.18, i915
  supports neither Android's sync_fence, nor upstream's sync_file, nor
  drm_syncobj. Again, I tested these patches on Android with a 3.18
  kernel and they work.

I plan to quickly follow-up with patches that remove the shortcuts and
properly import/export the sync fds.

Non-Testing
===========
I did not test at all using the Android.mk buildsystem. I probably
broke it. Please test and review that.

Testing
=======
I tested with 64-bit ARC++ on a Skylake Chromebook and a 3.18 kernel.
The following pass:

  a little spinning cube demo APK
  dEQP-VK.info.*
  dEQP-VK.api.smoke.*
  dEQP-VK.api.info.instance.*
  dEQP-VK.api.info.device.*
  dEQP-VK.api.wsi.android.*