From 44e1e7baa3b90b725efe1635e48083c04acba782 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu, 18 May 2017 21:48:11 +0100
Subject: [PATCH] drm/i915: Reorder media/render reset on g4x
Mime-version: 1.0
Content-type: text/plain; charset=UTF-8
Content-transfer-encoding: 8bit
Git-commit: 44e1e7baa3b90b725efe1635e48083c04acba782
Patch-mainline: v4.13-rc1
References: FATE#322643 bsc#1055900

Ville found a reference to WaMediaResetBeforeFullReset which we presume
means that we should simply do the media reset first.

References: https://bugs.freedesktop.org/show_bug.cgi?id=100942
Suggested-by: Ville Syrj채l채 <ville.syrjala@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrj채l채 <ville.syrjala@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170518204811.7408-2-chris@chris-wilson.co.uk
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/i915/intel_uncore.c |   27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -1468,16 +1468,9 @@ static int g4x_do_reset(struct drm_i915_
 	struct pci_dev *pdev = dev_priv->drm.pdev;
 	int ret;
 
-	pci_write_config_byte(pdev, I915_GDRST,
-			      GRDOM_RENDER | GRDOM_RESET_ENABLE);
-	ret =  wait_for(g4x_reset_complete(pdev), 500);
-	if (ret) {
-		DRM_DEBUG_DRIVER("Wait for render reset failed\n");
-		goto out;
-	}
-
 	/* WaVcpClkGateDisableForMediaReset:ctg,elk */
-	I915_WRITE(VDECCLK_GATE_D, I915_READ(VDECCLK_GATE_D) | VCP_UNIT_CLOCK_GATE_DISABLE);
+	I915_WRITE(VDECCLK_GATE_D,
+		   I915_READ(VDECCLK_GATE_D) | VCP_UNIT_CLOCK_GATE_DISABLE);
 	POSTING_READ(VDECCLK_GATE_D);
 
 	pci_write_config_byte(pdev, I915_GDRST,
@@ -1485,14 +1478,24 @@ static int g4x_do_reset(struct drm_i915_
 	ret =  wait_for(g4x_reset_complete(pdev), 500);
 	if (ret) {
 		DRM_DEBUG_DRIVER("Wait for media reset failed\n");
+		goto out;
 	}
 
-	/* WaVcpClkGateDisableForMediaReset:ctg,elk */
-	I915_WRITE(VDECCLK_GATE_D, I915_READ(VDECCLK_GATE_D) & ~VCP_UNIT_CLOCK_GATE_DISABLE);
-	POSTING_READ(VDECCLK_GATE_D);
+	pci_write_config_byte(pdev, I915_GDRST,
+			      GRDOM_RENDER | GRDOM_RESET_ENABLE);
+	ret =  wait_for(g4x_reset_complete(pdev), 500);
+	if (ret) {
+		DRM_DEBUG_DRIVER("Wait for render reset failed\n");
+		goto out;
+	}
 
 out:
 	pci_write_config_byte(pdev, I915_GDRST, 0);
+
+	I915_WRITE(VDECCLK_GATE_D,
+		   I915_READ(VDECCLK_GATE_D) & ~VCP_UNIT_CLOCK_GATE_DISABLE);
+	POSTING_READ(VDECCLK_GATE_D);
+
 	return ret;
 }