This is a bit like the CMN reset de-assert we do in DPIO_CTL, except that it resets the whole common lane section of the PHY. This is required on machines where the BIOS doesn't do this for us on resume to properly re-calibrate and get the PHY ready to transmit data.
Without this patch, such machines won't resume correctly much of the time, with the symptom being a 'port ready' timeout and/or a link training failure. I'm open to better suggestions on how to do the power well toggle, with the existing code it looks like I'd have to walk through a bunch of power domains looking for a match, then call a generic function which will warn. I'd prefer to just expose the specific domains directly for low level platform code like this. Signed-off-by: Jesse Barnes <jbar...@virtuousgeek.org> --- drivers/gpu/drm/i915/intel_pm.c | 4 ++-- drivers/gpu/drm/i915/intel_uncore.c | 19 +++++++++++++++++++ 2 files changed, 21 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index fa00185..3afd0bc 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -5454,8 +5454,8 @@ static bool i9xx_always_on_power_well_enabled(struct drm_i915_private *dev_priv, return true; } -static void vlv_set_power_well(struct drm_i915_private *dev_priv, - struct i915_power_well *power_well, bool enable) +void vlv_set_power_well(struct drm_i915_private *dev_priv, + struct i915_power_well *power_well, bool enable) { enum punit_power_well power_well_id = power_well->data; u32 mask; diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c index 2a72bab..f1abd2d 100644 --- a/drivers/gpu/drm/i915/intel_uncore.c +++ b/drivers/gpu/drm/i915/intel_uncore.c @@ -363,6 +363,9 @@ static void intel_uncore_forcewake_reset(struct drm_device *dev, bool restore) spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags); } +void vlv_set_power_well(struct drm_i915_private *dev_priv, + struct i915_power_well *power_well, bool enable); + void intel_uncore_early_sanitize(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; @@ -381,6 +384,22 @@ void intel_uncore_early_sanitize(struct drm_device *dev) DRM_INFO("Found %zuMB of eLLC\n", dev_priv->ellc_size); } + /* + * From VLV2A0_DP_eDP_HDMI_DPIO_driver_vbios_notes_11.docx: + * Need to assert and de-assert PHY SB reset by gating the common + * lane power, then un-gating it. + * Simply ungating isn't enough to reset the PHY enough to get + * ports and lanes running. + */ + if (IS_VALLEYVIEW(dev)) { + struct i915_power_well cmn_well = { + .data = PUNIT_POWER_WELL_DPIO_CMN_BC + }; + + vlv_set_power_well(dev_priv, &cmn_well, false); + vlv_set_power_well(dev_priv, &cmn_well, true); + } + /* clear out old GT FIFO errors */ if (IS_GEN6(dev) || IS_GEN7(dev)) __raw_i915_write32(dev_priv, GTFIFODBG, -- 1.7.9.5 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx