[Intel-gfx] [PATCH] drm/i915: Don't reset the display on gdg

[Chris Wilson]

Not a real fix, just to try and provoke some insight into the problem.

After lots of inconclusion bisecting, the only thing that is clear is
that between

commit e2c8b8701e2d0cb5b89fa3b5c8acae9dc4f76259
Author: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
Date:   Tue Feb 16 10:06:14 2016 +0100

    drm/i915: Use atomic helpers for suspend, v2.

and

commit dfa2997055659b4e706a85fba481050cc7e7ad82
Author: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
Date:   Fri Aug 5 23:28:27 2016 +0300

    drm/i915: Fix modeset handling during gpu reset, v5.

the modeset following the GPU reset causes a hard hang on i915g and
i915gm.

References: https://bugs.freedesktop.org/show_bug.cgi?id=101852
Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 8d9f19292052..6d299a9a4351 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3769,7 +3769,8 @@ void intel_finish_reset(struct drm_i915_private *dev_priv)
 			dev_priv->display.hpd_irq_setup(dev_priv);
 		spin_unlock_irq(&dev_priv->irq_lock);
 
-		ret = __intel_display_resume(dev, state, ctx);
+		ret = 0;
+		//ret = __intel_display_resume(dev, state, ctx);
 		if (ret)
 			DRM_ERROR("Restoring old state failed with %i\n", ret);
 
-- 
2.14.1