From: Jesse Barnes <jbarnes@virtuousgeek.org>
Date: Tue, 5 Nov 2013 00:07:00 +0000 (-0800)
Subject: drm/i915/vlv: fixup DDR freq detection per Punit spec
X-Git-Tag: firefly_0821_release~176^2~4523^2~90^2~71
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=f64a28a7c5ab2fc342326de9e126acf3cc0f91d6;p=firefly-linux-kernel-4.4.55.git

drm/i915/vlv: fixup DDR freq detection per Punit spec

Either the docs were wrong or the values have changed since the old days
before we had wheels.

Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 13afd54ca6e9..a5778e59cc15 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -5319,15 +5319,22 @@ static void valleyview_init_clock_gating(struct drm_device *dev)
 	mutex_unlock(&dev_priv->rps.hw_lock);
 	switch ((val >> 6) & 3) {
 	case 0:
-	case 1:
 		dev_priv->mem_freq = 800;
 		break;
-	case 2:
+	case 1:
 		dev_priv->mem_freq = 1066;
 		break;
-	case 3:
+	case 2:
 		dev_priv->mem_freq = 1333;
 		break;
+	case 3:
+		/*
+		 * Probably a BIOS/Punit bug, or a new platform we don't
+		 * support yet.
+		 */
+		WARN(1, "invalid DDR freq detected, assuming 800MHz\n");
+		dev_priv->mem_freq = 800;
+		break;
 	}
 	DRM_DEBUG_DRIVER("DDR speed: %d MHz", dev_priv->mem_freq);