[Intel-gfx] [PATCH 10/10] drm/i915: Allow PPGTT enable to fail

[Ben Widawsky]

From: Ben Widawsky <benjamin.widawsky at intel.com>

I'm really not happy that we have to support this, but this will be the
simplest way to handle cases where PPGTT init can fail, which I promise
will be coming in the future.

v2: Resolve conflicts due to patch series reordering.

Signed-off-by: Ben Widawsky <ben at bwidawsk.net> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 drivers/gpu/drm/i915/i915_drv.c     | 7 +++++--
 drivers/gpu/drm/i915/i915_drv.h     | 2 +-
 drivers/gpu/drm/i915/i915_gem.c     | 9 +++++++--
 drivers/gpu/drm/i915/i915_gem_gtt.c | 3 ++-
 4 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 70d10de..bddb9a5 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -927,8 +927,11 @@ int i915_reset(struct drm_device *dev)
 			ring->init(ring);
 
 		i915_gem_context_init(dev);
-		if (dev_priv->mm.aliasing_ppgtt)
-			dev_priv->mm.aliasing_ppgtt->enable(dev);
+		if (dev_priv->mm.aliasing_ppgtt) {
+			ret = dev_priv->mm.aliasing_ppgtt->enable(dev);
+			if (ret)
+				i915_gem_cleanup_aliasing_ppgtt(dev);
+		}
 
 		/*
 		 * It would make sense to re-init all the other hw state, at
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index c121321..f59a388 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -449,7 +449,7 @@ struct i915_hw_ppgtt {
 			       struct sg_table *st,
 			       unsigned int pg_start,
 			       enum i915_cache_level cache_level);
-	void (*enable)(struct drm_device *dev);
+	int (*enable)(struct drm_device *dev);
 	void (*cleanup)(struct i915_hw_ppgtt *ppgtt);
 };
 
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 8a73a68..da6d6de 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -4029,8 +4029,13 @@ i915_gem_init_hw(struct drm_device *dev)
 	 * contexts before PPGTT.
 	 */
 	i915_gem_context_init(dev);
-	if (dev_priv->mm.aliasing_ppgtt)
-		dev_priv->mm.aliasing_ppgtt->enable(dev);
+	if (dev_priv->mm.aliasing_ppgtt) {
+		ret = dev_priv->mm.aliasing_ppgtt->enable(dev);
+		if (ret) {
+			i915_gem_cleanup_aliasing_ppgtt(dev);
+			DRM_INFO("PPGTT enable failed. This is not fatal, but unexpected\n");
+		}
+	}
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index d32912e..11143b4 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -75,7 +75,7 @@ static inline gen6_gtt_pte_t gen6_pte_encode(struct drm_device *dev,
 	return pte;
 }
 
-static void gen6_ppgtt_enable(struct drm_device *dev)
+static int gen6_ppgtt_enable(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = dev->dev_private;
 	uint32_t pd_offset;
@@ -128,6 +128,7 @@ static void gen6_ppgtt_enable(struct drm_device *dev)
 		I915_WRITE(RING_PP_DIR_DCLV(ring), PP_DIR_DCLV_2G);
 		I915_WRITE(RING_PP_DIR_BASE(ring), pd_offset);
 	}
+	return 0;
 }
 
 /* PPGTT support for Sandybdrige/Gen6 and later */
-- 
1.8.2.1