From f05bb0c7b624252a5e768287e340e8e45df96e42 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Sun, 20 Jan 2013 16:33:32 +0000 Subject: [PATCH] drm/i915: GFX_MODE Flush TLB Invalidate Mode must be '1' for scanline waits On SNB, if bit 13 of GFX_MODE, Flush TLB Invalidate Mode, is not set to 1, the hardware can not program the scanline values. Those scanline values then control when the signal is sent from the display engine to the render ring for MI_WAIT_FOR_EVENTs. Note setting this bit means that TLB invalidations must be performed explicitly through the appropriate bits being set in PIPE_CONTROL. References: https://bugzilla.kernel.org/show_bug.cgi?id=52311 Signed-off-by: Chris Wilson Cc: stable@vger.kernel.org Reviewed-by: Ben Widawsky Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_ringbuffer.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 1f46a8b..42ff97d 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -515,6 +515,11 @@ static int init_render_ring(struct intel_ring_buffer *ring) if (INTEL_INFO(dev)->gen >= 6) I915_WRITE(MI_MODE, _MASKED_BIT_ENABLE(ASYNC_FLIP_PERF_DISABLE)); + /* Required for the hardware to program scanline values for waiting */ + if (INTEL_INFO(dev)->gen == 6) + I915_WRITE(GFX_MODE, + _MASKED_BIT_ENABLE(GFX_TLB_INVALIDATE_ALWAYS)); + if (IS_GEN7(dev)) I915_WRITE(GFX_MODE_GEN7, _MASKED_BIT_DISABLE(GFX_TLB_INVALIDATE_ALWAYS) | -- 2.7.4