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

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 78191e0..d48c02a 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1836,7 +1836,7 @@ 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... */
@@ -1859,6 +1859,7 @@ 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 7fb362f..604b20f 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -3362,6 +3362,7 @@ 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 8525196..e812993 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2758,7 +2758,7 @@ 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;
@@ -2780,6 +2780,11 @@ 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);