From 1c8fdda1ea947ae8cf994969a1c285acc7089cb9 Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Fri, 12 Feb 2016 18:55:15 +0200 Subject: [PATCH] drm/i915/crt: Ensure the HW is powered during HW state readout The assumption when adding the intel_display_power_is_enabled() checks was that if it returns success the power can't be turned off afterwards during the HW access, which is guaranteed by modeset locks. This isn't always true, so make sure we hold a dedicated reference for the time of the access. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93439 CC: Chris Wilson Signed-off-by: Imre Deak Reviewed-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-7-git-send-email-imre.deak@intel.com --- drivers/gpu/drm/i915/intel_crt.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c index ad5dfabc452e..e686a91a416e 100644 --- a/drivers/gpu/drm/i915/intel_crt.c +++ b/drivers/gpu/drm/i915/intel_crt.c @@ -71,22 +71,29 @@ static bool intel_crt_get_hw_state(struct intel_encoder *encoder, struct intel_crt *crt = intel_encoder_to_crt(encoder); enum intel_display_power_domain power_domain; u32 tmp; + bool ret; power_domain = intel_display_port_power_domain(encoder); - if (!intel_display_power_is_enabled(dev_priv, power_domain)) + if (!intel_display_power_get_if_enabled(dev_priv, power_domain)) return false; + ret = false; + tmp = I915_READ(crt->adpa_reg); if (!(tmp & ADPA_DAC_ENABLE)) - return false; + goto out; if (HAS_PCH_CPT(dev)) *pipe = PORT_TO_PIPE_CPT(tmp); else *pipe = PORT_TO_PIPE(tmp); - return true; + ret = true; +out: + intel_display_power_put(dev_priv, power_domain); + + return ret; } static unsigned int intel_crt_get_flags(struct intel_encoder *encoder) -- 2.30.2