Commit 3f2e9ed0 authored Dec 20, 2018 by Imre Deak

drm/i915/icl: Detect port F presence via VBT

Registering an output for a non-existent port (on a given SKU) can lead
to problems when trying to use the port, for instance timeouts during
power well enabling. Since there are no strap bits for port detection we
have to rely on VBT for this, so do that here.

There are no known SKUs where any of the A-E ports are non-existent, so
to reduce the likelihood of breakage due to incorrect VBT information,
do this detection only for port F (which is known to be missing on some
ICL SKUs).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108915


Cc: Mika Kahola <mika.kahola@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181220132604.25222-2-imre.deak@intel.com


Reviewed-by: Jani Nikula <jani.nikula@intel.com>

parent e9d49bb7

drivers/gpu/drm/i915/intel_display.c

+7 −1

Original line number	Diff line number	Diff line
		@@ -14320,7 +14320,13 @@ static void intel_setup_outputs(struct drm_i915_private *dev_priv)
		intel_ddi_init(dev_priv, PORT_C);
		intel_ddi_init(dev_priv, PORT_D);
		intel_ddi_init(dev_priv, PORT_E);
		/*
		* On some ICL SKUs port F is not present. No strap bits for
		* this, so rely on VBT.
		*/
		if (intel_bios_is_port_present(dev_priv, PORT_F))
		intel_ddi_init(dev_priv, PORT_F);

		icl_dsi_init(dev_priv);
		} else if (IS_GEN9_LP(dev_priv)) {
		/*