From 317b2cac79a66c7156dbe7983b825dc417acf9a8 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Fri, 13 Dec 2019 15:34:48 +0200 Subject: [PATCH] drm/i915/fbc: Reject PLANE_OFFSET.y%4!=0 on icl+ too MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit icl and tgl are still affected by the modulo 4 PLANE_OFFSET.y underrun issue. Reject such configurations on all gen9+ platforms. Can be reproduced easily with the following sequence of hardware poking: while { write FBC_CTL.enable=1 wait for vblank write PLANE_OFFSET .x=0 .y=32 write PLANE_SURF wait for vblank # if PLANE_OFFSET.y is multiple of 4 the underrun won't happen write PLANE_OFFSET .x=0 .y=31 write PLANE_SURF wait for vblank # extra vblank wait is required here presumably # to get FBC into the proper state wait for vblank write FBC_CTL.enable=0 # underrun happens some time after FBC disable wait for vblank } Both 8888 and 565 pixel formats and all tilinga formats seem affected. Reproduced on KBL/GLK/ICL/TGL. BDW confirmed not affected. Closes: https://gitlab.freedesktop.org/drm/intel/issues/792 Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20191213133453.22152-1-ville.syrjala@linux.intel.com Reviewed-by: Imre Deak --- drivers/gpu/drm/i915/display/intel_fbc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c index 6f1d5c032681..a1048ece541e 100644 --- a/drivers/gpu/drm/i915/display/intel_fbc.c +++ b/drivers/gpu/drm/i915/display/intel_fbc.c @@ -776,7 +776,7 @@ static bool intel_fbc_can_activate(struct intel_crtc *crtc) * having a Y offset that isn't divisible by 4 causes FIFO underrun * and screen flicker. */ - if (IS_GEN_RANGE(dev_priv, 9, 10) && + if (INTEL_GEN(dev_priv) >= 9 && (fbc->state_cache.plane.adjusted_y & 3)) { fbc->no_fbc_reason = "plane Y offset is misaligned"; return false; -- 2.30.2