[Intel-gfx] [PATCH 4/4] drm/i915: fix PCH_NOP setting for non-PCH platforms

[Jani Nikula]

Setting PCH type to PCH_NOP before checking whether we actually have a
PCH ends up returning true for HAS_PCH_SPLIT() on all non-PCH split
platforms. Fix this by using PCH_NOP only for platforms that actually
have a PCH.

Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 1842a067a604..5deee698881b 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -246,14 +246,6 @@ static void intel_detect_pch(struct drm_i915_private *dev_priv)
 {
 	struct pci_dev *pch = NULL;
 
-	/* In all current cases, num_pipes is equivalent to the PCH_NOP setting
-	 * (which really amounts to a PCH but no South Display).
-	 */
-	if (INTEL_INFO(dev_priv)->num_pipes == 0) {
-		dev_priv->pch_type = PCH_NOP;
-		return;
-	}
-
 	/*
 	 * The reason to probe ISA bridge instead of Dev31:Fun0 is to
 	 * make graphics device passthrough work easy for VMM, that only
@@ -293,6 +285,17 @@ static void intel_detect_pch(struct drm_i915_private *dev_priv)
 			break;
 		}
 	}
+
+	/*
+	 * Use PCH_NOP (PCH but no South Display) for PCH platforms without
+	 * display.
+	 */
+	if (pch && INTEL_INFO(dev_priv)->num_pipes == 0) {
+		DRM_DEBUG_KMS("Display disabled, reverting to NOP PCH\n");
+		dev_priv->pch_type = PCH_NOP;
+		dev_priv->pch_id = 0;
+	}
+
 	if (!pch)
 		DRM_DEBUG_KMS("No PCH found.\n");
 
-- 
2.11.0