drm/i915: Split GEM resetting into 3 phases

Currently we do a reset prepare/finish around the call to reset the GPU,
but it looks like we need a later stage after the hw has been
reinitialised to allow GEM to restart itself. Start by splitting the 2
GEM phases into 3:

  prepare - before the reset, check if GEM recovered, then stop GEM

  reset - after the reset, update GEM bookkeeping

  finish - after the re-initialisation following the reset, restart GEM

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170208143033.11651-2-chris@chris-wilson.co.uk
Link: http://patchwork.freedesktop.org/patch/msgid/20170313165958.13970-1-chris@chris-wilson.co.uk
(cherry picked from commit d80270931314a88d79d9bd5e0a5df93c12196375)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index e703556..2093d20 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1788,7 +1788,7 @@ void i915_reset(struct drm_i915_private *dev_priv)
                goto error;
        }
 
-       i915_gem_reset_finish(dev_priv);
+       i915_gem_reset(dev_priv);
        intel_overlay_reset(dev_priv);
 
        /* Ok, now get things going again... */
@@ -1811,6 +1811,7 @@ void i915_reset(struct drm_i915_private *dev_priv)
                goto error;
        }
 
+       i915_gem_reset_finish(dev_priv);
        i915_queue_hangcheck(dev_priv);
 
 wakeup:

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 7febe6e..1d20c2d 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -3342,6 +3342,7 @@ static inline u32 i915_reset_count(struct i915_gpu_error *error)
 }
 
 int i915_gem_reset_prepare(struct drm_i915_private *dev_priv);
+void i915_gem_reset(struct drm_i915_private *dev_priv);
 void i915_gem_reset_finish(struct drm_i915_private *dev_priv);
 void i915_gem_set_wedged(struct drm_i915_private *dev_priv);
 void i915_gem_clflush_object(struct drm_i915_gem_object *obj, bool force);

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 10777da..27fe5a9 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2834,7 +2834,7 @@ static void i915_gem_reset_engine(struct intel_engine_cs *engine)
        engine->reset_hw(engine, request);
 }
 
-void i915_gem_reset_finish(struct drm_i915_private *dev_priv)
+void i915_gem_reset(struct drm_i915_private *dev_priv)
 {
        struct intel_engine_cs *engine;
        enum intel_engine_id id;
@@ -2856,6 +2856,11 @@ void i915_gem_reset_finish(struct drm_i915_private *dev_priv)
        }
 }
 
+void i915_gem_reset_finish(struct drm_i915_private *dev_priv)
+{
+       lockdep_assert_held(&dev_priv->drm.struct_mutex);
+}
+
 static void nop_submit_request(struct drm_i915_gem_request *request)
 {
        dma_fence_set_error(&request->fence, -EIO);