drm/i915/gen6+: Clear upper data byte during PCODE write
authorImre Deak <imre.deak@intel.com>
Mon, 28 Nov 2016 15:29:27 +0000 (17:29 +0200)
committerImre Deak <imre.deak@intel.com>
Fri, 2 Dec 2016 14:32:44 +0000 (16:32 +0200)
commit8bf41b7298b3b20de3f4a4e70ab58042648f963e
treea77f0dc8ffd90496bb8b44ead0c223c025e7963b
parentf55d23be11ed15f493957246f3b81fc530e79d70
drm/i915/gen6+: Clear upper data byte during PCODE write

The spec calls for the upper data byte to be cleared before most of the
PCODE write commands, for others like IPS control it doesn't say
anything about this byte. Let's clear it in case it's clobbered somehow,
especially that there are places where we only do a PCODE write without
a preceding PCODE read.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1480346969-16121-1-git-send-email-imre.deak@intel.com
drivers/gpu/drm/i915/intel_pm.c