From: Ben Widawsky Date: Mon, 30 Jun 2014 16:53:43 +0000 (-0700) Subject: drm/i915/bdw: poll semaphores X-Git-Tag: omap-for-v3.17/fixes-against-rc2~125^2~49^2~54 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bae4fcd2c7b778a3f69e03e244221cd4932b8f67;p=pandora-kernel.git drm/i915/bdw: poll semaphores As Ville points out, it's possible/probable we don't actually need this. Potentially, this validates the letter of the spec, and not the spirit. Ville: > I discussed this on irc w/ Ben, and I was suggesting we don't need to > poll. Polling apparently can be used as a workaround for certain > hardware issues, but it looks like those issues shouldn't affect us, > for the momemnt at least. So my suggestion was to try w/o polling > first (since there could be some power cost to polling) and add the > poll bit if problems arise. Rodrigo: Spec suggests this as an W/A for GT3. However semaphores didn't worked in my BDW GT2 on Signal Mode. So pool mode is definitely needed. Reviewed-by: Rodrigo Vivi Tested-by: Rodrigo Vivi Signed-off-by: Ben Widawsky Signed-off-by: Rodrigo Vivi Signed-off-by: Daniel Vetter --- Reading git-diff-tree failed