From 47baf2a5332de6cfb21d1e7e0d2e36640362ff48 Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Wed, 20 Apr 2016 20:46:06 +0300 Subject: [PATCH] drm/i915/bxt: Force reprogramming a PHY with invalid HW state MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It's possible that BIOS enables PHY0, but it programmes only the first channel on it. Since we program the PHYs only during driver loading this is an incorrect configuration from the driver's point of view, since we may use both channels eventually. Detect this scenario and force reprogramming the PHY in this case. The actual scenario for me was that the lane optimization for the second channel in PHY0 was not setup by BIOS and so a state verification warning was triggered. Everything else was setup properly. Signed-off-by: Imre Deak Reviewed-by: Ville Syrjälä Link: http://patchwork.freedesktop.org/patch/msgid/1461174366-16758-4-git-send-email-imre.deak@intel.com --- drivers/gpu/drm/i915/intel_ddi.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index 99da8f555954..e30e1781fd71 100644 --- a/drivers/gpu/drm/i915/intel_ddi.c +++ b/drivers/gpu/drm/i915/intel_ddi.c @@ -1775,6 +1775,9 @@ static void broxton_phy_wait_grc_done(struct drm_i915_private *dev_priv, DRM_ERROR("timeout waiting for PHY%d GRC\n", phy); } +static bool broxton_phy_verify_state(struct drm_i915_private *dev_priv, + enum dpio_phy phy); + static void broxton_phy_init(struct drm_i915_private *dev_priv, enum dpio_phy phy) { @@ -1782,16 +1785,22 @@ static void broxton_phy_init(struct drm_i915_private *dev_priv, u32 ports, val; if (broxton_phy_is_enabled(dev_priv, phy)) { - DRM_DEBUG_DRIVER("DDI PHY %d already enabled, " - "won't reprogram it\n", phy); /* Still read out the GRC value for state verification */ if (phy == DPIO_PHY0) dev_priv->bxt_phy_grc = broxton_get_grc(dev_priv, phy); - return; - } + if (broxton_phy_verify_state(dev_priv, phy)) { + DRM_DEBUG_DRIVER("DDI PHY %d already enabled, " + "won't reprogram it\n", phy); - DRM_DEBUG_DRIVER("DDI PHY %d not enabled, enabling it\n", phy); + return; + } + + DRM_DEBUG_DRIVER("DDI PHY %d enabled with invalid state, " + "force reprogramming it\n", phy); + } else { + DRM_DEBUG_DRIVER("DDI PHY %d not enabled, enabling it\n", phy); + } val = I915_READ(BXT_P_CR_GT_DISP_PWRON); val |= GT_DISPLAY_POWER_ON(phy);