From 935a0ff0e1ea62a116848c0a187b13838f7b9cee Mon Sep 17 00:00:00 2001 From: Francisco Jerez Date: Wed, 13 Jan 2016 18:59:39 -0800 Subject: [PATCH] drm/i915: Make sure DC writes are coherent on flush. MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit We need to set the DC FLUSH PIPE_CONTROL bit on Gen7+ to guarantee that writes performed via the HDC are visible in memory. Fixes an intermittent failure in a Piglit test that writes to a BO from a shader using GL atomic counters (implemented as HDC untyped atomics) and then expects the memory to read back the same value after mapping it on the CPU. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91298 Tested-by: Mark Janes Cc: Rodrigo Vivi Cc: stable@vger.kernel.org Signed-off-by: Francisco Jerez Reviewed-by: Ville Syrjälä Link: http://patchwork.freedesktop.org/patch/msgid/1452740379-3194-1-git-send-email-currojerez@riseup.net (cherry picked from commit 965fd602a6436f689f4f2fe40a6789582778ccd5) Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/intel_lrc.c | 1 + drivers/gpu/drm/i915/intel_ringbuffer.c | 2 ++ 2 files changed, 3 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 3aa614731d7e..f1fa756c5d5d 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -1707,6 +1707,7 @@ static int gen8_emit_flush_render(struct drm_i915_gem_request *request, if (flush_domains) { flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH; flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH; + flags |= PIPE_CONTROL_DC_FLUSH_ENABLE; flags |= PIPE_CONTROL_FLUSH_ENABLE; } diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 339701d7a9a5..40c6aff57256 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -331,6 +331,7 @@ gen7_render_ring_flush(struct drm_i915_gem_request *req, if (flush_domains) { flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH; flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH; + flags |= PIPE_CONTROL_DC_FLUSH_ENABLE; flags |= PIPE_CONTROL_FLUSH_ENABLE; } if (invalidate_domains) { @@ -403,6 +404,7 @@ gen8_render_ring_flush(struct drm_i915_gem_request *req, if (flush_domains) { flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH; flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH; + flags |= PIPE_CONTROL_DC_FLUSH_ENABLE; flags |= PIPE_CONTROL_FLUSH_ENABLE; } if (invalidate_domains) { -- 2.39.5