drm/i915: announce to userspace that the bsd ring is coherent

Otherwise we can't really fix the abi-braindeadness of forcing
libva to manually wait for rendering when switching rings. Which
in turn makes implementing hw semaphores a pointless exercise
(at least for ironlake).

[Also added the relaxed fencing param to explain the jump in
numbering - relaxed fencing is in -next.]

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 7a26f4dd21ae0a055036f78ce588ea4def08d73a..e6800819bca846f6a3fd102ef37e2632858247f8 100644 (file)
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -767,6 +767,9 @@ static int i915_getparam(struct drm_device *dev, void *data,
        case I915_PARAM_HAS_BLT:
                value = HAS_BLT(dev);
                break;
+       case I915_PARAM_HAS_COHERENT_RINGS:
+               value = 1;
+               break;
        default:
                DRM_DEBUG_DRIVER("Unknown parameter %d\n",
                                 param->param);

diff --git a/include/drm/i915_drm.h b/include/drm/i915_drm.h
index 8c641bed9bbd36526870b6741fdd16f780e3b0ec..a2776e2807a4ce39051df02b7384da32d58c1545 100644 (file)
--- a/include/drm/i915_drm.h
+++ b/include/drm/i915_drm.h
@@ -287,6 +287,8 @@ typedef struct drm_i915_irq_wait {
 #define I915_PARAM_HAS_EXECBUF2          9
 #define I915_PARAM_HAS_BSD              10
 #define I915_PARAM_HAS_BLT              11
+#define I915_PARAM_HAS_RELAXED_FENCING  12
+#define I915_PARAM_HAS_COHERENT_RINGS   13
 
 typedef struct drm_i915_getparam {
        int param;