[PATCH] drm/i915: don't try DP_LINK_BW_5_4 on HSW ULX

[Paulo Zanoni <przanoni@gmail.com>]

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

Because the docs say ULX doesn't support it on HSW.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h | 3 +++
 drivers/gpu/drm/i915/intel_dp.c | 3 ++-
 include/drm/i915_pciids.h       | 4 ++--
 3 files changed, 7 insertions(+), 3 deletions(-)


This patch is completely untested!!!


diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index e81feab..bdc612c 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1816,6 +1816,9 @@ struct drm_i915_cmd_table {
 #define IS_ULT(dev)		(IS_HSW_ULT(dev) || IS_BDW_ULT(dev))
 #define IS_HSW_GT3(dev)		(IS_HASWELL(dev) && \
 				 ((dev)->pdev->device & 0x00F0) == 0x0020)
+/* ULX machines are also considered ULT. */
+#define IS_HSW_ULX(dev)		((dev)->pdev->device == 0x0A0E || \
+				 (dev)->pdev->device == 0x0A1E)
 #define IS_PRELIMINARY_HW(intel_info) ((intel_info)->is_preliminary)
 
 /*
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 34ed143..87b0a51 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -105,7 +105,8 @@ intel_dp_max_link_bw(struct intel_dp *intel_dp)
 	case DP_LINK_BW_2_7:
 		break;
 	case DP_LINK_BW_5_4: /* 1.2 capable displays may advertise higher bw */
-		if ((IS_HASWELL(dev) || INTEL_INFO(dev)->gen >= 8) &&
+		if (((IS_HASWELL(dev) && !IS_HSW_ULX(dev)) ||
+		     INTEL_INFO(dev)->gen >= 8) &&
 		    intel_dp->dpcd[DP_DPCD_REV] >= 0x12)
 			max_link_bw = DP_LINK_BW_5_4;
 		else
diff --git a/include/drm/i915_pciids.h b/include/drm/i915_pciids.h
index 24f3cad..5cd9165 100644
--- a/include/drm/i915_pciids.h
+++ b/include/drm/i915_pciids.h
@@ -191,8 +191,8 @@
 	INTEL_VGA_DEVICE(0x0A06, info), /* ULT GT1 mobile */ \
 	INTEL_VGA_DEVICE(0x0A16, info), /* ULT GT2 mobile */ \
 	INTEL_VGA_DEVICE(0x0A26, info), /* ULT GT3 mobile */ \
-	INTEL_VGA_DEVICE(0x0A0E, info), /* ULT GT1 reserved */ \
-	INTEL_VGA_DEVICE(0x0A1E, info), /* ULT GT2 reserved */ \
+	INTEL_VGA_DEVICE(0x0A0E, info), /* ULX GT1 mobile */ \
+	INTEL_VGA_DEVICE(0x0A1E, info), /* ULX GT2 mobile */ \
 	INTEL_VGA_DEVICE(0x0A2E, info), /* ULT GT3 reserved */ \
 	INTEL_VGA_DEVICE(0x0D06, info), /* CRW GT1 mobile */ \
 	INTEL_VGA_DEVICE(0x0D16, info), /* CRW GT2 mobile */ \
-- 
1.9.2