From: Jani Nikula Date: Fri, 9 May 2014 11:52:34 +0000 (+0300) Subject: drm/i915/vlv: reset VLV media force wake request register X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e3fe5945d5fff076366e852440c7c2e9c7b7d17c;p=karo-tx-linux.git drm/i915/vlv: reset VLV media force wake request register commit 05adaf1f101f25f40f12c29403e6488f0e45f6b6 upstream. Media force wake get hangs the machine when the system is booted without displays attached. The assumption is that (at least some versions of) the firmware has skipped some initialization in that case. Empirical evidence suggests we need to reset the media force wake request register in addition to the render one to avoid hangs. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=75895 Reported-by: Imre Deak Reported-by: Darren Hart Tested-by: Darren Hart Reviewed-by: Mika Kuoppala Signed-off-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c index 87df68f5f504..c8796316d242 100644 --- a/drivers/gpu/drm/i915/intel_uncore.c +++ b/drivers/gpu/drm/i915/intel_uncore.c @@ -177,6 +177,8 @@ static void vlv_force_wake_reset(struct drm_i915_private *dev_priv) { __raw_i915_write32(dev_priv, FORCEWAKE_VLV, _MASKED_BIT_DISABLE(0xffff)); + __raw_i915_write32(dev_priv, FORCEWAKE_MEDIA_VLV, + _MASKED_BIT_DISABLE(0xffff)); /* something from same cacheline, but !FORCEWAKE_VLV */ __raw_posting_read(dev_priv, FORCEWAKE_ACK_VLV); }