From: Daniel Vetter Date: Sat, 8 Dec 2012 11:58:33 +0000 (+0100) Subject: drm/i915: disable cpt phase pointer fdi rx workaround X-Git-Tag: v3.2.36~54 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3d66fd735d84acb52b09fd5c441e3b206cd226a5;p=pandora-kernel.git drm/i915: disable cpt phase pointer fdi rx workaround commit 539526b4137bc0e7a8806c38c8522f226814a0e6 upstream. We've originally added this in commit 291427f5fdadec6e4be2924172e83588880e1539 Author: Jesse Barnes Date: Fri Jul 29 12:42:37 2011 -0700 drm/i915: apply phase pointer override on SNB+ too and then copy-pasted it over to ivb/ppt. The w/a was originally added for ilk/ibx in commit 5b2adf897146edeac6a1e438fb67b5a53dbbdf34 Author: Jesse Barnes Date: Thu Oct 7 16:01:15 2010 -0700 drm/i915: add Ironlake clock gating workaround for FDI link training and fixed up a bit in commit 6f06ce184c765fd8d50669a8d12fdd566c920859 Author: Jesse Barnes Date: Tue Jan 4 15:09:38 2011 -0800 drm/i915: set phase sync pointer override enable before setting phase sync pointer It turns out that this w/a isn't actually required on cpt/ppt and positively harmful on ivb/ppt when using fdi B/C links - it results in a black screen occasionally, with seemingfully everything working as it should. The only failure indication I've found in the hw is that eventually (but not right after the modeset completes) a pipe underrun is signalled. Big thanks to Arthur Runyan for all the ideas for registers to check and changes to test, otherwise I couldn't ever have tracked this down! Cc: "Runyan, Arthur J" Reviewed-by: Jesse Barnes Signed-off-by: Daniel Vetter [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- Reading git-diff-tree failed