[Intel-gfx] [PATCH] drm/i915/display: Suppress "Combo PHY A HW state changed unexpectedly"

[Chris Wilson]

We know a problem exists in the ifwi shipped with the early
pre-production Tigerlake and DG1 prototypes, later revisions are fine.
However, CI still relies on the earlier ifwi and we grow tired of
the volume of warnings as we wait for replacements.

Since the warning is a bug, we do not want to lose the warning in its
entirety, so only suppress the warning for the platforms currently
exhibiting the issue.

Suggested-by: José Roberto de Souza <gitlab at gitlab.freedesktop.org>
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2411
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: José Roberto de Souza <jose.souza at intel.com>
---
 .../gpu/drm/i915/display/intel_combo_phy.c    | 20 +++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_combo_phy.c b/drivers/gpu/drm/i915/display/intel_combo_phy.c
index d5ad61e4083e..996ae0608a62 100644
--- a/drivers/gpu/drm/i915/display/intel_combo_phy.c
+++ b/drivers/gpu/drm/i915/display/intel_combo_phy.c
@@ -427,10 +427,22 @@ static void icl_combo_phys_uninit(struct drm_i915_private *dev_priv)
 		u32 val;
 
 		if (phy == PHY_A &&
-		    !icl_combo_phy_verify_state(dev_priv, phy))
-			drm_warn(&dev_priv->drm,
-				 "Combo PHY %c HW state changed unexpectedly\n",
-				 phy_name(phy));
+		    !icl_combo_phy_verify_state(dev_priv, phy)) {
+			if (IS_TIGERLAKE(dev_priv) || IS_DG1(dev_priv)) {
+				/*
+				 * A known problem with old ifwi:
+				 * https://gitlab.freedesktop.org/drm/intel/-/issues/2411
+				 * Suppress the warning for CI. Remove ASAP!
+				 */
+				drm_dbg_kms(&dev_priv->drm,
+					    "Combo PHY %c HW state changed unexpectedly\n",
+					    phy_name(phy));
+			} else {
+				drm_warn(&dev_priv->drm,
+					 "Combo PHY %c HW state changed unexpectedly\n",
+					 phy_name(phy));
+			}
+		}
 
 		if (!has_phy_misc(dev_priv, phy))
 			goto skip_phy_misc;
-- 
2.20.1