From 91ce4668b8dd0442c1b167149c821267504a42e0 Mon Sep 17 00:00:00 2001
From: Alex Deucher <alexander.deucher@amd.com>
Date: Fri, 27 Jan 2017 10:31:52 -0500
Subject: [PATCH] drm/amdgpu/si: fix crash on headless asics

Missing check for crtcs present.
Backported fix by Luya Tshimbalanga

Fixes:
https://bugzilla.kernel.org/show_bug.cgi?id=193341
https://bugs.freedesktop.org/show_bug.cgi?id=99387

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org


diff -ruN linux-4.9.6-20170203.amd.fc25.x86_64.orig/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c linux-4.9.6-20170203.amd.fc25.x86_64/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c
--- linux-4.9.6-20170203.amd.fc25.x86_64.orig/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c	2017-02-03 20:22:39.555283318 -0800
+++ linux-4.9.6-20170203.amd.fc25.x86_64/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c	2017-02-03 20:01:40.053298148 -0800
@@ -254,6 +254,10 @@
 	}
 	WREG32(mmHDP_REG_COHERENCY_FLUSH_CNTL, 0);
 
+ 
+	if (adev->mode_info.num_crtc)
+		amdgpu_display_set_vga_render_state(adev, false);
+
 	gmc_v6_0_mc_stop(adev, &save);
 
 	if (gmc_v6_0_wait_for_idle((void *)adev)) {
@@ -283,7 +287,6 @@
 		dev_warn(adev->dev, "Wait for MC idle timedout !\n");
 	}
 	gmc_v6_0_mc_resume(adev, &save);
-	amdgpu_display_set_vga_render_state(adev, false);
 }
 
 static int gmc_v6_0_mc_init(struct amdgpu_device *adev)