drm/i915: Apply the PPS register unlock workaround more consistently
Atm, we apply this workaround somewhat inconsistently at the following
points: driver loading, LVDS init, eDP PPS init, system resume. As this
workaround also affects registers other than PPS (timing, PLL) a more
consistent way is to apply it early after the PPS HW context is known to
be lost: driver loading, system resume and on VLV/CHV/BXT when turning
on power domains.
This is needed by the next patch that removes saving/restoring of the
PP_CONTROL register.
This also removes the incorrect programming of the workaround on HSW+
PCH platforms which don't have the register locking mechanism.
v2: (Ville)
- Don't apply the workaround on BXT.
- Simplify platform checks using HAS_DDI().
v3:
- Move the call of intel_pps_unlock_regs_wa() to the more
logical vlv_display_power_well_init() (also fixing CHV) (Ville).
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470827254-21954-5-git-send-email-imre.deak@intel.com
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 2ef7b14..364db90 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1829,7 +1829,8 @@
lockdep_assert_held(&dev_priv->pps_mutex);
control = I915_READ(_pp_ctrl_reg(intel_dp));
- if (!IS_BROXTON(dev)) {
+ if (WARN_ON(!HAS_DDI(dev_priv) &&
+ (control & PANEL_UNLOCK_MASK) != PANEL_UNLOCK_REGS)) {
control &= ~PANEL_UNLOCK_MASK;
control |= PANEL_UNLOCK_REGS;
}