drm/i915/bdw: Enable resource streamer on Broadwell

[Abdiel Janulgue <abdiel.janulgue@linux.intel.com>]

From: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>

This is a re-spin of my resource streamer patchset from October
adapted to enable the feature on Broadwell instead.

The resource streamer is a hw-feature that helps in reducing commands
being submitted by the CPU. Haswell initially has this feature.
Unfortunately, HSW seems to have problems switching between non-RS
and RS-enabled commands[1]. On BDW however it works seamlessly
as expected.

The i-g-t test comes next on a separate patch-series.

--
[1] http://lists.freedesktop.org/archives/intel-gfx/2014-May/044577.html 

Abdiel Janulgue (2):
      drm/i915/bdw: Enable resource streamer bits on MI_BATCH_BUFFER_START
      drm/i915/bdw: Expose I915_EXEC_RESOURCE_STREAMER flag

 drivers/gpu/drm/i915/i915_gem_execbuffer.c |    8 ++++++++
 drivers/gpu/drm/i915/i915_reg.h            |    1 +
 drivers/gpu/drm/i915/intel_ringbuffer.c    |    3 ++-
 drivers/gpu/drm/i915/intel_ringbuffer.h    |    1 +
 include/uapi/drm/i915_drm.h                |    7 ++++++-
 5 files changed, 18 insertions(+), 2 deletions(-)