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* [PATCH 1/3] drm/virtio: skip set_scanout if framebuffer didn't change
       [not found] <20191211084216.25405-1-kraxel@redhat.com>
@ 2019-12-11  8:42 ` Gerd Hoffmann
  2019-12-11 18:27   ` Chia-I Wu
  2019-12-11  8:42 ` [PATCH 2/3] virtio-gpu: batch display update commands Gerd Hoffmann
  2019-12-11  8:42 ` [PATCH 3/3] virtio-gpu: use damage info for display updates Gerd Hoffmann
  2 siblings, 1 reply; 5+ messages in thread
From: Gerd Hoffmann @ 2019-12-11  8:42 UTC (permalink / raw)
  To: dri-devel
  Cc: gurchetansingh, Gerd Hoffmann, David Airlie, Daniel Vetter,
	open list:VIRTIO GPU DRIVER, open list

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/virtio/virtgpu_plane.c | 31 ++++++++++++++------------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
index bc4bc4475a8c..a0f91658c2bc 100644
--- a/drivers/gpu/drm/virtio/virtgpu_plane.c
+++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
@@ -151,20 +151,23 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
 	if (bo->dumb)
 		virtio_gpu_update_dumb_bo(vgdev, bo, plane->state);
 
-	DRM_DEBUG("handle 0x%x, crtc %dx%d+%d+%d, src %dx%d+%d+%d\n",
-		  bo->hw_res_handle,
-		  plane->state->crtc_w, plane->state->crtc_h,
-		  plane->state->crtc_x, plane->state->crtc_y,
-		  plane->state->src_w >> 16,
-		  plane->state->src_h >> 16,
-		  plane->state->src_x >> 16,
-		  plane->state->src_y >> 16);
-	virtio_gpu_cmd_set_scanout(vgdev, output->index,
-				   bo->hw_res_handle,
-				   plane->state->src_w >> 16,
-				   plane->state->src_h >> 16,
-				   plane->state->src_x >> 16,
-				   plane->state->src_y >> 16);
+	if (plane->state->fb != old_state->fb) {
+		DRM_DEBUG("handle 0x%x, crtc %dx%d+%d+%d, src %dx%d+%d+%d\n",
+			  bo->hw_res_handle,
+			  plane->state->crtc_w, plane->state->crtc_h,
+			  plane->state->crtc_x, plane->state->crtc_y,
+			  plane->state->src_w >> 16,
+			  plane->state->src_h >> 16,
+			  plane->state->src_x >> 16,
+			  plane->state->src_y >> 16);
+		virtio_gpu_cmd_set_scanout(vgdev, output->index,
+					   bo->hw_res_handle,
+					   plane->state->src_w >> 16,
+					   plane->state->src_h >> 16,
+					   plane->state->src_x >> 16,
+					   plane->state->src_y >> 16);
+	}
+
 	virtio_gpu_cmd_resource_flush(vgdev, bo->hw_res_handle,
 				      plane->state->src_x >> 16,
 				      plane->state->src_y >> 16,
-- 
2.18.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 2/3] virtio-gpu: batch display update commands.
       [not found] <20191211084216.25405-1-kraxel@redhat.com>
  2019-12-11  8:42 ` [PATCH 1/3] drm/virtio: skip set_scanout if framebuffer didn't change Gerd Hoffmann
@ 2019-12-11  8:42 ` Gerd Hoffmann
  2019-12-11  8:42 ` [PATCH 3/3] virtio-gpu: use damage info for display updates Gerd Hoffmann
  2 siblings, 0 replies; 5+ messages in thread
From: Gerd Hoffmann @ 2019-12-11  8:42 UTC (permalink / raw)
  To: dri-devel
  Cc: gurchetansingh, Gerd Hoffmann, David Airlie, Daniel Vetter,
	open list:VIRTIO GPU DRIVER, open list

When the driver submits multiple commands in a row it makes sense to
notify the host only after submitting the last one, so the host can
process them all at once, with a single vmexit.

Add functions to enable/disable notifications to allow that.  Use the
new functions for primary plane updates.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/virtio/virtgpu_drv.h   |  6 ++++++
 drivers/gpu/drm/virtio/virtgpu_plane.c |  4 ++++
 drivers/gpu/drm/virtio/virtgpu_vq.c    | 23 +++++++++++++++++++++--
 3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index eedae2a7b532..29cf005ed6b9 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -183,6 +183,9 @@ struct virtio_gpu_device {
 	struct kmem_cache *vbufs;
 	bool vqs_ready;
 
+	bool disable_notify;
+	bool pending_notify;
+
 	struct ida	resource_ida;
 
 	wait_queue_head_t resp_wq;
@@ -335,6 +338,9 @@ void virtio_gpu_dequeue_ctrl_func(struct work_struct *work);
 void virtio_gpu_dequeue_cursor_func(struct work_struct *work);
 void virtio_gpu_dequeue_fence_func(struct work_struct *work);
 
+void virtio_gpu_disable_notify(struct virtio_gpu_device *vgdev);
+void virtio_gpu_enable_notify(struct virtio_gpu_device *vgdev);
+
 /* virtio_gpu_display.c */
 int virtio_gpu_framebuffer_init(struct drm_device *dev,
 				struct virtio_gpu_framebuffer *vgfb,
diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
index a0f91658c2bc..2e0d14e005db 100644
--- a/drivers/gpu/drm/virtio/virtgpu_plane.c
+++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
@@ -146,6 +146,8 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
 		return;
 	}
 
+	virtio_gpu_disable_notify(vgdev);
+
 	vgfb = to_virtio_gpu_framebuffer(plane->state->fb);
 	bo = gem_to_virtio_gpu_obj(vgfb->base.obj[0]);
 	if (bo->dumb)
@@ -173,6 +175,8 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
 				      plane->state->src_y >> 16,
 				      plane->state->src_w >> 16,
 				      plane->state->src_h >> 16);
+
+	virtio_gpu_enable_notify(vgdev);
 }
 
 static int virtio_gpu_cursor_prepare_fb(struct drm_plane *plane,
diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 9274c4063c70..5914e79d3429 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -404,8 +404,12 @@ static void virtio_gpu_queue_fenced_ctrl_buffer(struct virtio_gpu_device *vgdev,
 	}
 	notify = virtio_gpu_queue_ctrl_buffer_locked(vgdev, vbuf, vout);
 	spin_unlock(&vgdev->ctrlq.qlock);
-	if (notify)
-		virtqueue_notify(vgdev->ctrlq.vq);
+	if (notify) {
+		if (vgdev->disable_notify)
+			vgdev->pending_notify = true;
+		else
+			virtqueue_notify(vgdev->ctrlq.vq);
+	}
 
 	if (sgt) {
 		sg_free_table(sgt);
@@ -413,6 +417,21 @@ static void virtio_gpu_queue_fenced_ctrl_buffer(struct virtio_gpu_device *vgdev,
 	}
 }
 
+void virtio_gpu_disable_notify(struct virtio_gpu_device *vgdev)
+{
+	vgdev->disable_notify = true;
+}
+
+void virtio_gpu_enable_notify(struct virtio_gpu_device *vgdev)
+{
+	vgdev->disable_notify = false;
+
+	if (!vgdev->pending_notify)
+		return;
+	vgdev->pending_notify = false;
+	virtqueue_notify(vgdev->ctrlq.vq);
+}
+
 static void virtio_gpu_queue_ctrl_buffer(struct virtio_gpu_device *vgdev,
 					 struct virtio_gpu_vbuffer *vbuf)
 {
-- 
2.18.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 3/3] virtio-gpu: use damage info for display updates.
       [not found] <20191211084216.25405-1-kraxel@redhat.com>
  2019-12-11  8:42 ` [PATCH 1/3] drm/virtio: skip set_scanout if framebuffer didn't change Gerd Hoffmann
  2019-12-11  8:42 ` [PATCH 2/3] virtio-gpu: batch display update commands Gerd Hoffmann
@ 2019-12-11  8:42 ` Gerd Hoffmann
  2019-12-11 19:03   ` Chia-I Wu
  2 siblings, 1 reply; 5+ messages in thread
From: Gerd Hoffmann @ 2019-12-11  8:42 UTC (permalink / raw)
  To: dri-devel
  Cc: gurchetansingh, Gerd Hoffmann, David Airlie, Daniel Vetter,
	open list:VIRTIO GPU DRIVER, open list

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 drivers/gpu/drm/virtio/virtgpu_plane.c | 41 +++++++++++++++-----------
 1 file changed, 24 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
index 2e0d14e005db..1a0fbbb91ec7 100644
--- a/drivers/gpu/drm/virtio/virtgpu_plane.c
+++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
@@ -24,6 +24,7 @@
  */
 
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_damage_helper.h>
 #include <drm/drm_fourcc.h>
 #include <drm/drm_plane_helper.h>
 
@@ -103,22 +104,26 @@ static int virtio_gpu_plane_atomic_check(struct drm_plane *plane,
 }
 
 static void virtio_gpu_update_dumb_bo(struct virtio_gpu_device *vgdev,
-				      struct virtio_gpu_object *bo,
-				      struct drm_plane_state *state)
+				      struct drm_plane_state *state,
+				      struct drm_rect *rect)
 {
+	struct virtio_gpu_object *bo =
+		gem_to_virtio_gpu_obj(state->fb->obj[0]);
 	struct virtio_gpu_object_array *objs;
+	uint32_t w = rect->x2 - rect->x1;
+	uint32_t h = rect->y2 - rect->y1;
+	uint32_t x = rect->x1 + (state->src_x >> 16);
+	uint32_t y = rect->y1 + (state->src_y >> 16);
+	uint32_t off = x * state->fb->format->cpp[0] +
+		y * state->fb->pitches[0];
 
 	objs = virtio_gpu_array_alloc(1);
 	if (!objs)
 		return;
 	virtio_gpu_array_add_obj(objs, &bo->base.base);
-	virtio_gpu_cmd_transfer_to_host_2d
-		(vgdev, 0,
-		 state->src_w >> 16,
-		 state->src_h >> 16,
-		 state->src_x >> 16,
-		 state->src_y >> 16,
-		 objs, NULL);
+
+	virtio_gpu_cmd_transfer_to_host_2d(vgdev, off, w, h, x, y,
+					   objs, NULL);
 }
 
 static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
@@ -127,8 +132,8 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
 	struct drm_device *dev = plane->dev;
 	struct virtio_gpu_device *vgdev = dev->dev_private;
 	struct virtio_gpu_output *output = NULL;
-	struct virtio_gpu_framebuffer *vgfb;
 	struct virtio_gpu_object *bo;
+	struct drm_rect rect;
 
 	if (plane->state->crtc)
 		output = drm_crtc_to_virtio_gpu_output(plane->state->crtc);
@@ -146,12 +151,14 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
 		return;
 	}
 
+	if (!drm_atomic_helper_damage_merged(old_state, plane->state, &rect))
+		return;
+
 	virtio_gpu_disable_notify(vgdev);
 
-	vgfb = to_virtio_gpu_framebuffer(plane->state->fb);
-	bo = gem_to_virtio_gpu_obj(vgfb->base.obj[0]);
+	bo = gem_to_virtio_gpu_obj(plane->state->fb->obj[0]);
 	if (bo->dumb)
-		virtio_gpu_update_dumb_bo(vgdev, bo, plane->state);
+		virtio_gpu_update_dumb_bo(vgdev, plane->state, &rect);
 
 	if (plane->state->fb != old_state->fb) {
 		DRM_DEBUG("handle 0x%x, crtc %dx%d+%d+%d, src %dx%d+%d+%d\n",
@@ -171,10 +178,10 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
 	}
 
 	virtio_gpu_cmd_resource_flush(vgdev, bo->hw_res_handle,
-				      plane->state->src_x >> 16,
-				      plane->state->src_y >> 16,
-				      plane->state->src_w >> 16,
-				      plane->state->src_h >> 16);
+				      (plane->state->src_x >> 16) + rect.x1,
+				      (plane->state->src_y >> 16) + rect.y1,
+				      rect.x2 - rect.x1,
+				      rect.y2 - rect.y1);
 
 	virtio_gpu_enable_notify(vgdev);
 }
-- 
2.18.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH 1/3] drm/virtio: skip set_scanout if framebuffer didn't change
  2019-12-11  8:42 ` [PATCH 1/3] drm/virtio: skip set_scanout if framebuffer didn't change Gerd Hoffmann
@ 2019-12-11 18:27   ` Chia-I Wu
  0 siblings, 0 replies; 5+ messages in thread
From: Chia-I Wu @ 2019-12-11 18:27 UTC (permalink / raw)
  To: Gerd Hoffmann
  Cc: ML dri-devel, David Airlie, open list,
	open list:VIRTIO GPU DRIVER, Gurchetan Singh

On Wed, Dec 11, 2019 at 12:42 AM Gerd Hoffmann <kraxel@redhat.com> wrote:
>
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  drivers/gpu/drm/virtio/virtgpu_plane.c | 31 ++++++++++++++------------
>  1 file changed, 17 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
> index bc4bc4475a8c..a0f91658c2bc 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_plane.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
> @@ -151,20 +151,23 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
>         if (bo->dumb)
>                 virtio_gpu_update_dumb_bo(vgdev, bo, plane->state);
>
> -       DRM_DEBUG("handle 0x%x, crtc %dx%d+%d+%d, src %dx%d+%d+%d\n",
> -                 bo->hw_res_handle,
> -                 plane->state->crtc_w, plane->state->crtc_h,
> -                 plane->state->crtc_x, plane->state->crtc_y,
> -                 plane->state->src_w >> 16,
> -                 plane->state->src_h >> 16,
> -                 plane->state->src_x >> 16,
> -                 plane->state->src_y >> 16);
> -       virtio_gpu_cmd_set_scanout(vgdev, output->index,
> -                                  bo->hw_res_handle,
> -                                  plane->state->src_w >> 16,
> -                                  plane->state->src_h >> 16,
> -                                  plane->state->src_x >> 16,
> -                                  plane->state->src_y >> 16);
> +       if (plane->state->fb != old_state->fb) {
Should we check src_{w,h,x,y} as well?
> +               DRM_DEBUG("handle 0x%x, crtc %dx%d+%d+%d, src %dx%d+%d+%d\n",
> +                         bo->hw_res_handle,
> +                         plane->state->crtc_w, plane->state->crtc_h,
> +                         plane->state->crtc_x, plane->state->crtc_y,
> +                         plane->state->src_w >> 16,
> +                         plane->state->src_h >> 16,
> +                         plane->state->src_x >> 16,
> +                         plane->state->src_y >> 16);
> +               virtio_gpu_cmd_set_scanout(vgdev, output->index,
> +                                          bo->hw_res_handle,
> +                                          plane->state->src_w >> 16,
> +                                          plane->state->src_h >> 16,
> +                                          plane->state->src_x >> 16,
> +                                          plane->state->src_y >> 16);
> +       }
> +
>         virtio_gpu_cmd_resource_flush(vgdev, bo->hw_res_handle,
>                                       plane->state->src_x >> 16,
>                                       plane->state->src_y >> 16,
> --
> 2.18.1
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH 3/3] virtio-gpu: use damage info for display updates.
  2019-12-11  8:42 ` [PATCH 3/3] virtio-gpu: use damage info for display updates Gerd Hoffmann
@ 2019-12-11 19:03   ` Chia-I Wu
  0 siblings, 0 replies; 5+ messages in thread
From: Chia-I Wu @ 2019-12-11 19:03 UTC (permalink / raw)
  To: Gerd Hoffmann
  Cc: ML dri-devel, David Airlie, open list,
	open list:VIRTIO GPU DRIVER, Gurchetan Singh

On Wed, Dec 11, 2019 at 12:42 AM Gerd Hoffmann <kraxel@redhat.com> wrote:
>
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  drivers/gpu/drm/virtio/virtgpu_plane.c | 41 +++++++++++++++-----------
>  1 file changed, 24 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
> index 2e0d14e005db..1a0fbbb91ec7 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_plane.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
> @@ -24,6 +24,7 @@
>   */
>
>  #include <drm/drm_atomic_helper.h>
> +#include <drm/drm_damage_helper.h>
>  #include <drm/drm_fourcc.h>
>  #include <drm/drm_plane_helper.h>
>
> @@ -103,22 +104,26 @@ static int virtio_gpu_plane_atomic_check(struct drm_plane *plane,
>  }
>
>  static void virtio_gpu_update_dumb_bo(struct virtio_gpu_device *vgdev,
> -                                     struct virtio_gpu_object *bo,
> -                                     struct drm_plane_state *state)
> +                                     struct drm_plane_state *state,
> +                                     struct drm_rect *rect)
>  {
> +       struct virtio_gpu_object *bo =
> +               gem_to_virtio_gpu_obj(state->fb->obj[0]);
>         struct virtio_gpu_object_array *objs;
> +       uint32_t w = rect->x2 - rect->x1;
> +       uint32_t h = rect->y2 - rect->y1;
> +       uint32_t x = rect->x1 + (state->src_x >> 16);
> +       uint32_t y = rect->y1 + (state->src_y >> 16);
> +       uint32_t off = x * state->fb->format->cpp[0] +
> +               y * state->fb->pitches[0];
>
>         objs = virtio_gpu_array_alloc(1);
>         if (!objs)
>                 return;
>         virtio_gpu_array_add_obj(objs, &bo->base.base);
> -       virtio_gpu_cmd_transfer_to_host_2d
> -               (vgdev, 0,
> -                state->src_w >> 16,
> -                state->src_h >> 16,
> -                state->src_x >> 16,
> -                state->src_y >> 16,
> -                objs, NULL);
> +
> +       virtio_gpu_cmd_transfer_to_host_2d(vgdev, off, w, h, x, y,
> +                                          objs, NULL);
>  }
>
>  static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
> @@ -127,8 +132,8 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
>         struct drm_device *dev = plane->dev;
>         struct virtio_gpu_device *vgdev = dev->dev_private;
>         struct virtio_gpu_output *output = NULL;
> -       struct virtio_gpu_framebuffer *vgfb;
>         struct virtio_gpu_object *bo;
> +       struct drm_rect rect;
>
>         if (plane->state->crtc)
>                 output = drm_crtc_to_virtio_gpu_output(plane->state->crtc);
> @@ -146,12 +151,14 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
>                 return;
>         }
>
> +       if (!drm_atomic_helper_damage_merged(old_state, plane->state, &rect))
> +               return;
> +
>         virtio_gpu_disable_notify(vgdev);
>
> -       vgfb = to_virtio_gpu_framebuffer(plane->state->fb);
> -       bo = gem_to_virtio_gpu_obj(vgfb->base.obj[0]);
> +       bo = gem_to_virtio_gpu_obj(plane->state->fb->obj[0]);
>         if (bo->dumb)
> -               virtio_gpu_update_dumb_bo(vgdev, bo, plane->state);
> +               virtio_gpu_update_dumb_bo(vgdev, plane->state, &rect);
>
>         if (plane->state->fb != old_state->fb) {
>                 DRM_DEBUG("handle 0x%x, crtc %dx%d+%d+%d, src %dx%d+%d+%d\n",
> @@ -171,10 +178,10 @@ static void virtio_gpu_primary_plane_update(struct drm_plane *plane,
>         }
>
>         virtio_gpu_cmd_resource_flush(vgdev, bo->hw_res_handle,
> -                                     plane->state->src_x >> 16,
> -                                     plane->state->src_y >> 16,
> -                                     plane->state->src_w >> 16,
> -                                     plane->state->src_h >> 16);
> +                                     (plane->state->src_x >> 16) + rect.x1,
> +                                     (plane->state->src_y >> 16) + rect.y1,
Digging into drm_atomic_helper_damage_merged, it seems rect uses
absolute values and is not relative to src_{x,y}.

> +                                     rect.x2 - rect.x1,
> +                                     rect.y2 - rect.y1);
>
>         virtio_gpu_enable_notify(vgdev);
>  }
> --
> 2.18.1
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2019-12-11 19:04 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <20191211084216.25405-1-kraxel@redhat.com>
2019-12-11  8:42 ` [PATCH 1/3] drm/virtio: skip set_scanout if framebuffer didn't change Gerd Hoffmann
2019-12-11 18:27   ` Chia-I Wu
2019-12-11  8:42 ` [PATCH 2/3] virtio-gpu: batch display update commands Gerd Hoffmann
2019-12-11  8:42 ` [PATCH 3/3] virtio-gpu: use damage info for display updates Gerd Hoffmann
2019-12-11 19:03   ` Chia-I Wu

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