On Mon, Aug 13, 2018 at 4:26 PM Heiko Stuebner [off-list ref] wrote:

Am Montag, 13. August 2018, 09:11:07 CEST schrieb Tomasz Figa:

quoted

Hi Enric,

On Tue, Aug 7, 2018 at 12:53 AM Enric Balletbo i Serra
[off-list ref] wrote:

quoted

Add support to async updates of cursors by using the new atomic
interface for that.

Signed-off-by: Enric Balletbo i Serra <redacted>
---
Hi,

This first version is slightly different from the RFC, note that I did
not maintain the Sean reviewed tag for that reason. With this version I
don't touch the atomic_update function and all is implemented in the
async_check/update functions. See the changelog for a list of changes.

The patch was tested on a Samsung Chromebook Plus in two ways.

 1. Running all igt kms_cursor_legacy and kms_atomic at plane_cursor_legacy
    tests and see that there is no regression after the patch.

 2. Running weston using the atomic API.

Thanks for the patch. This feature might look like a really minor
thing, but we really had hard time dealing with users complaints, so
having this in upstream would be a really useful thing.

Let me post some comments inline.

quoted

Best regards,
  Enric

Changes in v1:
- Rebased on top of drm-misc
- In async_check call drm_atomic_helper_check_plane_state to check that
  the desired plane is valid and update various bits of derived state
  (clipped coordinates etc.)
- In async_check allow to configure new scaling in the fast path.
- In async_update force to flush all registered PSR encoders.
- In async_update call atomic_update directly.
- In async_update call vop_cfg_done needed to set the vop registers and take effect.

 drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 53 +++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index e9f91278137d..dab70056ee73 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c

@@ -811,10 +811,63 @@ static void vop_plane_atomic_update(struct drm_plane *plane,
        spin_unlock(&vop->reg_lock);
 }

+static int vop_plane_atomic_async_check(struct drm_plane *plane,
+                                       struct drm_plane_state *state)
+{
+       struct vop_win *vop_win = to_vop_win(plane);
+       const struct vop_win_data *win = vop_win->data;
+       int min_scale = win->phy->scl ? FRAC_16_16(1, 8) :
+                                       DRM_PLANE_HELPER_NO_SCALING;
+       int max_scale = win->phy->scl ? FRAC_16_16(8, 1) :
+                                       DRM_PLANE_HELPER_NO_SCALING;
+       int ret;
+
+       if (plane != state->crtc->cursor)
+               return -EINVAL;
+
+       if (!plane->state)
+               return -EINVAL;
+
+       if (!plane->state->fb ||
+           plane->state->fb != state->fb)
+               return -EINVAL;

While it covers for quite a big part of cursor movements, you may
still expect jumpy cursor when hoovering text boxes or hyperlinks,
since it changes the cursor image. Our downstream patch [1] actually
took care of changing the framebuffer as well, although with the added
complexity of referencing the old buffer at update time and releasing
it in a flip work.

[1] https://chromium.git.corp.google.com/chromiumos/third_party/kernel/+/1ad887e1a1349991c9e137b48cb32086e65347fc%5E%21/

[1] https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/394492
for non-google people ;-)

Thanks, not sure how that internal link sneaked into my clipboard.
Should have checked what I pasted. :P

Best regards,
Tomasz