[PATCH 3.16.y-ckt 100/135] drm/i915: Fix and clean BDW PCH identification

[Luis Henriques]

3.16.7-ckt6 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Rodrigo Vivi <rodrigo.vivi at intel.com>

commit a35cc9d0c0118fb18f7c5dd7a44adb454868a679 upstream.

It seems in the past we have BDW with PCH not been propperly identified
and we force it to be LPT and we were warning !IS_HASWELL on propper identification.

Now that products are out there we are receiveing logs with this incorrect WARN.
And also according to local tests on all production BDW here ULT or HALO we don't
need this force anymore. So let's clean this block for real.

v2: Fix LPT_LP WARNs to avoid wrong warns on BDW_ULT (By Jani).

Reference: https://bugs.freedesktop.org/attachment.cgi?id=110972

Cc: Jani Nikula <jani.nikula at intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni at intel.com>
Cc: Xion Zhang <xiong.y.zhang at intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
Signed-off-by: Jani Nikula <jani.nikula at intel.com>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/gpu/drm/i915/i915_drv.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index b470281c98e3..e35e32f33e31 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -449,19 +449,13 @@ void intel_detect_pch(struct drm_device *dev)
 			} else if (id == INTEL_PCH_LPT_DEVICE_ID_TYPE) {
 				dev_priv->pch_type = PCH_LPT;
 				DRM_DEBUG_KMS("Found LynxPoint PCH\n");
-				WARN_ON(!IS_HASWELL(dev));
-				WARN_ON(IS_HSW_ULT(dev));
-			} else if (IS_BROADWELL(dev)) {
-				dev_priv->pch_type = PCH_LPT;
-				dev_priv->pch_id =
-					INTEL_PCH_LPT_LP_DEVICE_ID_TYPE;
-				DRM_DEBUG_KMS("This is Broadwell, assuming "
-					      "LynxPoint LP PCH\n");
+				WARN_ON(!IS_HASWELL(dev) && !IS_BROADWELL(dev));
+				WARN_ON(IS_HSW_ULT(dev) || IS_BDW_ULT(dev));
 			} else if (id == INTEL_PCH_LPT_LP_DEVICE_ID_TYPE) {
 				dev_priv->pch_type = PCH_LPT;
 				DRM_DEBUG_KMS("Found LynxPoint LP PCH\n");
-				WARN_ON(!IS_HASWELL(dev));
-				WARN_ON(!IS_HSW_ULT(dev));
+				WARN_ON(!IS_HASWELL(dev) && !IS_BROADWELL(dev));
+				WARN_ON(!IS_HSW_ULT(dev) && !IS_BDW_ULT(dev));
 			} else
 				continue;
 
-- 
2.1.4