| From | Luis Henriques <> | Subject | [PATCH 3.11 019/131] drm/i915: Prevent MI_DISPLAY_FLIP straddling two cachelines on IVB | Date | Wed, 5 Mar 2014 14:22:23 +0000 |
| |
3.11.10.6 -stable review patch. If anyone has any objections, please let me know.
------------------
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com>
commit f66fab8e1cd6b3127ba4c5c0d11539fbe1de1e36 upstream.
According to BSpec the entire MI_DISPLAY_FLIP packet must be contained in a single cacheline. Make sure that happens.
v2: Use intel_ring_begin_cacheline_safe() v3: Use intel_ring_cacheline_align() (Chris)
Cc: Bjoern C <lkml@call-home.ch> Cc: Alexandru DAMIAN <alexandru.damian@intel.com> Cc: Enrico Tagliavini <enrico.tagliavini@gmail.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=74053 Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> [ luis: backported to 3.11: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/gpu/drm/i915/intel_display.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 0e3f213..5df9798 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -7477,6 +7477,20 @@ static int intel_gen7_queue_flip(struct drm_device *dev, goto err_unpin; } + /* + * BSpec MI_DISPLAY_FLIP for IVB: + * "The full packet must be contained within the same cache line." + * + * Currently the LRI+SRM+MI_DISPLAY_FLIP all fit within the same + * cacheline, if we ever start emitting more commands before + * the MI_DISPLAY_FLIP we may need to first emit everything else, + * then do the cacheline alignment, and finally emit the + * MI_DISPLAY_FLIP. + */ + ret = intel_ring_cacheline_align(ring); + if (ret) + goto err_unpin; + ret = intel_ring_begin(ring, 4); if (ret) goto err_unpin; -- 1.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|