[Intel-gfx] [PATCH v2] drm/i915: WARN if a port should use VBT provided vswing tables

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

We don't parse the VBT vswing/preemphassis tables at all currently.
Let's WARN if a port wants to use them so we get a heads up that
whether we really need to implement this stuff or not. My
current stash contains no VBTs with this bit set.

v2: Move to print_ddi_port() (Jani)

Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_bios.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
index 28bdb936cd1f..4c543e8205ca 100644
--- a/drivers/gpu/drm/i915/display/intel_bios.c
+++ b/drivers/gpu/drm/i915/display/intel_bios.c
@@ -2676,6 +2676,14 @@ static void print_ddi_port(const struct intel_bios_encoder_data *devdata,
 		drm_dbg_kms(&i915->drm,
 			    "Port %c VBT DP max link rate: %d\n",
 			    port_name(port), dp_max_link_rate);
+
+	/*
+	 * FIXME need to implement support for VBT
+	 * vswing/preemph tables should this ever trigger.
+	 */
+	drm_WARN(&i915->drm, child->use_vbt_vswing,
+		 "Port %c asks to use VBT vswing/preemph tables\n",
+		 port_name(port));
 }
 
 static void parse_ddi_port(struct intel_bios_encoder_data *devdata)
-- 
2.35.1