diff mbox

[7/7] drm/i915/vlv: Use Blitter Engine to clear out contents of Stolen frame buffers

Message ID 1389245516-11219-1-git-send-email-akash.goel@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

akash.goel@intel.com Jan. 9, 2014, 5:31 a.m. UTC
From: Akash Goel <akash.goel@intel.com>

On VLV, to clear out the contents of Frame buffers allocated from
stolen area, Blitter engine is being used, to avoid the waste of
CPU cycles in doing a sw based memset.

Signed-off-by: Akash Goel <akash.goel@intel.com>
---
 drivers/gpu/drm/i915/i915_gem_stolen.c | 87 ++++++++++++++++++++++++++++++++--
 1 file changed, 84 insertions(+), 3 deletions(-)

Comments

Daniel Vetter Jan. 9, 2014, 7:35 a.m. UTC | #1
On Thu, Jan 09, 2014 at 11:01:56AM +0530, akash.goel@intel.com wrote:
> From: Akash Goel <akash.goel@intel.com>
> 
> On VLV, to clear out the contents of Frame buffers allocated from
> stolen area, Blitter engine is being used, to avoid the waste of
> CPU cycles in doing a sw based memset.
> 
> Signed-off-by: Akash Goel <akash.goel@intel.com>
> ---
>  drivers/gpu/drm/i915/i915_gem_stolen.c | 87 ++++++++++++++++++++++++++++++++--
>  1 file changed, 84 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
> index 253a39a..10237c8 100644
> --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
> +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
> @@ -371,7 +371,84 @@ i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
>  	return NULL;
>  }
>  
> -static void i915_memset_stolen_obj(struct drm_i915_gem_object *obj)
> +static int i915_add_clear_obj_cmd(struct drm_i915_gem_object *obj)
> +{
> +	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
> +	struct intel_ring_buffer *ring = &dev_priv->ring[BCS];

Pre-gen6 has the blitter on the RCS ring.

> +	uint32_t obj_height = (obj->base.size / obj->stride);

obj->stride is 0 for untiled buffers, so for more robustness I'd just use
4096 (page size) as stride. For even more robustness I think we should
have checks here to make sure that we don't overflow blitter hw limits
here.

> +	u32 offset = i915_gem_obj_ggtt_offset(obj);
> +	int ret;
> +
> +#define	COLOR_BLIT_OP		((0x2 << 29) | (0x40 << 22) | (0x3 << 20) | 0x3)
> +#define	COLOR_BLIT_OP_DW1	((0x3 << 24) | (0xF0 << 16) | (obj->stride))
> +#define	COLOR_BLIT_OP_DW2	((obj_height << 16) | (obj->stride))
> +#define	COLOR_BLIT_OP_DW3	(offset)
> +#define	COLOR_BLIT_OP_DW4	(0x0)

These #defines imo don't help readability, everywhere else
(kernel/userspace) we construct the cmd dwords in-line in the
OUT_BATCH/intel_ring_emit calls. Also please use the existing XY_ blt cmd
#defines in i915_reg.h.
- Daniel

> +
> +	ret = intel_ring_begin(ring, 6);
> +	if (ret)
> +		return ret;
> +	intel_ring_emit(ring, COLOR_BLIT_OP);
> +	intel_ring_emit(ring, COLOR_BLIT_OP_DW1);
> +	intel_ring_emit(ring, COLOR_BLIT_OP_DW2);
> +	intel_ring_emit(ring, COLOR_BLIT_OP_DW3);
> +	intel_ring_emit(ring, COLOR_BLIT_OP_DW4);
> +	intel_ring_emit(ring, MI_NOOP);
> +	intel_ring_advance(ring);
> +
> +	return 0;
> +}
> +
> +static int i915_memset_stolen_obj_hw(struct drm_i915_gem_object *obj)
> +{
> +	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
> +	struct intel_ring_buffer *ring = &dev_priv->ring[BCS];
> +	unsigned alignment = 0;
> +	bool map_and_fenceable =  true;
> +	bool nonblocking = false;
> +	u32 seqno;
> +	int ret;
> +
> +	ret = i915_gem_obj_ggtt_pin(obj, alignment, map_and_fenceable,
> +		nonblocking);
> +	if (ret) {
> +		DRM_ERROR("Mapping of User FB to GTT failed\n");
> +		return ret;
> +	}
> +
> +	/* Adding commands to the blitter ring to
> +	 * clear out the contents of the buffer object
> +	 */
> +	ret = i915_add_clear_obj_cmd(obj);
> +	if (ret) {
> +		DRM_ERROR("couldn't add commands in blitter ring\n");
> +		i915_gem_object_ggtt_unpin(obj);
> +		return ret;
> +	}
> +
> +	seqno = intel_ring_get_seqno(ring);
> +
> +	/* Object now in render domain */
> +	obj->base.read_domains = I915_GEM_DOMAIN_RENDER;
> +	obj->base.write_domain = I915_GEM_DOMAIN_RENDER;
> +
> +	i915_vma_move_to_active(i915_gem_obj_to_ggtt(obj), ring);
> +
> +	obj->dirty = 1;
> +	obj->last_write_seqno = seqno;
> +
> +	/* Unconditionally force add_request to emit a full flush. */
> +	ring->gpu_caches_dirty = true;
> +
> +	/* Add a breadcrumb for the completion of the clear request */
> +	(void)i915_add_request(ring, NULL);
> +
> +	i915_gem_object_ggtt_unpin(obj);
> +
> +	return 0;
> +}
> +
> +static void i915_memset_stolen_obj_sw(struct drm_i915_gem_object *obj)
>  {
>  	int ret;
>  	char __iomem *base;
> @@ -490,9 +567,13 @@ i915_gem_object_move_to_stolen(struct drm_i915_gem_object *obj)
>  	obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
>  
>  	/* Zero-out the contents of the stolen object, otherwise we observe
> -	 * corruptions in the display.
> +	 * corruptions in the display. First try using the blitter engine
> +	 * to clear the buffer contents
>  	 */
> -	i915_memset_stolen_obj(obj);
> +	ret = i915_memset_stolen_obj_hw(obj);
> +	/* fallback to Sw based memset if Hw memset fails */
> +	if (ret)
> +		i915_memset_stolen_obj_sw(obj);
>  	return;
>  
>  cleanup:
> -- 
> 1.8.5.2
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Chris Wilson Jan. 9, 2014, 9:46 a.m. UTC | #2
On Thu, Jan 09, 2014 at 11:01:56AM +0530, akash.goel@intel.com wrote:
> From: Akash Goel <akash.goel@intel.com>

Did I not ever send i915_gem_exec.c which does this correctly?
-Chris
akash.goel@intel.com Jan. 9, 2014, 9:50 a.m. UTC | #3
Sorry we have never received the i915_gem_exec.c file .
Please share that, we don't see it in the drm-intel-next also.  

Best Regards
Akash

-----Original Message-----
From: Chris Wilson [mailto:chris@chris-wilson.co.uk] 
Sent: Thursday, January 09, 2014 3:16 PM
To: Goel, Akash
Cc: intel-gfx@lists.freedesktop.org
Subject: Re: [Intel-gfx] [PATCH 7/7] drm/i915/vlv: Use Blitter Engine to clear out contents of Stolen frame buffers

On Thu, Jan 09, 2014 at 11:01:56AM +0530, akash.goel@intel.com wrote:
> From: Akash Goel <akash.goel@intel.com>

Did I not ever send i915_gem_exec.c which does this correctly?
-Chris
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 253a39a..10237c8 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -371,7 +371,84 @@  i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
 	return NULL;
 }
 
-static void i915_memset_stolen_obj(struct drm_i915_gem_object *obj)
+static int i915_add_clear_obj_cmd(struct drm_i915_gem_object *obj)
+{
+	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
+	struct intel_ring_buffer *ring = &dev_priv->ring[BCS];
+	uint32_t obj_height = (obj->base.size / obj->stride);
+	u32 offset = i915_gem_obj_ggtt_offset(obj);
+	int ret;
+
+#define	COLOR_BLIT_OP		((0x2 << 29) | (0x40 << 22) | (0x3 << 20) | 0x3)
+#define	COLOR_BLIT_OP_DW1	((0x3 << 24) | (0xF0 << 16) | (obj->stride))
+#define	COLOR_BLIT_OP_DW2	((obj_height << 16) | (obj->stride))
+#define	COLOR_BLIT_OP_DW3	(offset)
+#define	COLOR_BLIT_OP_DW4	(0x0)
+
+	ret = intel_ring_begin(ring, 6);
+	if (ret)
+		return ret;
+	intel_ring_emit(ring, COLOR_BLIT_OP);
+	intel_ring_emit(ring, COLOR_BLIT_OP_DW1);
+	intel_ring_emit(ring, COLOR_BLIT_OP_DW2);
+	intel_ring_emit(ring, COLOR_BLIT_OP_DW3);
+	intel_ring_emit(ring, COLOR_BLIT_OP_DW4);
+	intel_ring_emit(ring, MI_NOOP);
+	intel_ring_advance(ring);
+
+	return 0;
+}
+
+static int i915_memset_stolen_obj_hw(struct drm_i915_gem_object *obj)
+{
+	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
+	struct intel_ring_buffer *ring = &dev_priv->ring[BCS];
+	unsigned alignment = 0;
+	bool map_and_fenceable =  true;
+	bool nonblocking = false;
+	u32 seqno;
+	int ret;
+
+	ret = i915_gem_obj_ggtt_pin(obj, alignment, map_and_fenceable,
+		nonblocking);
+	if (ret) {
+		DRM_ERROR("Mapping of User FB to GTT failed\n");
+		return ret;
+	}
+
+	/* Adding commands to the blitter ring to
+	 * clear out the contents of the buffer object
+	 */
+	ret = i915_add_clear_obj_cmd(obj);
+	if (ret) {
+		DRM_ERROR("couldn't add commands in blitter ring\n");
+		i915_gem_object_ggtt_unpin(obj);
+		return ret;
+	}
+
+	seqno = intel_ring_get_seqno(ring);
+
+	/* Object now in render domain */
+	obj->base.read_domains = I915_GEM_DOMAIN_RENDER;
+	obj->base.write_domain = I915_GEM_DOMAIN_RENDER;
+
+	i915_vma_move_to_active(i915_gem_obj_to_ggtt(obj), ring);
+
+	obj->dirty = 1;
+	obj->last_write_seqno = seqno;
+
+	/* Unconditionally force add_request to emit a full flush. */
+	ring->gpu_caches_dirty = true;
+
+	/* Add a breadcrumb for the completion of the clear request */
+	(void)i915_add_request(ring, NULL);
+
+	i915_gem_object_ggtt_unpin(obj);
+
+	return 0;
+}
+
+static void i915_memset_stolen_obj_sw(struct drm_i915_gem_object *obj)
 {
 	int ret;
 	char __iomem *base;
@@ -490,9 +567,13 @@  i915_gem_object_move_to_stolen(struct drm_i915_gem_object *obj)
 	obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
 
 	/* Zero-out the contents of the stolen object, otherwise we observe
-	 * corruptions in the display.
+	 * corruptions in the display. First try using the blitter engine
+	 * to clear the buffer contents
 	 */
-	i915_memset_stolen_obj(obj);
+	ret = i915_memset_stolen_obj_hw(obj);
+	/* fallback to Sw based memset if Hw memset fails */
+	if (ret)
+		i915_memset_stolen_obj_sw(obj);
 	return;
 
 cleanup: