[Nouveau] [PATCH] nouveau/dispnv50: add cursor size/pitch checks

[Ilia Mirkin]

On Fri, Feb 5, 2021 at 11:45 AM Simon Ser <contact at emersion.fr> wrote:
>
> The hardware needs a FB which is packed and not too large. Add
> checks to make sure this is the case.
>
> While at it, add a debug log for the existing check. This allows
> user-space to more easily figure out why a configuration is
> rejected.
>
> This commit depends on "drm/nouveau/kms/nv50-: Report max cursor
> size to userspace", otherwise mode_config.cursor_{width,height}
> is zero.
>
> Signed-off-by: Simon Ser <contact at emersion.fr>
> Cc: Lyude Paul <lyude at redhat.com>
> Cc: Ben Skeggs <bskeggs at redhat.com>
> Cc: Ilia Mirkin <imirkin at alum.mit.edu>
> ---
>  drivers/gpu/drm/nouveau/dispnv50/curs507a.c | 22 ++++++++++++++++++++-
>  1 file changed, 21 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/curs507a.c b/drivers/gpu/drm/nouveau/dispnv50/curs507a.c
> index 54fbd6fe751d..9a401751c56d 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/curs507a.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/curs507a.c
> @@ -99,6 +99,7 @@ curs507a_acquire(struct nv50_wndw *wndw, struct nv50_wndw_atom *asyw,
>                  struct nv50_head_atom *asyh)
>  {
>         struct nv50_head *head = nv50_head(asyw->state.crtc);
> +       struct drm_device *dev = head->base.base.dev;
>         int ret;
>
>         ret = drm_atomic_helper_check_plane_state(&asyw->state, &asyh->state,
> @@ -109,8 +110,27 @@ curs507a_acquire(struct nv50_wndw *wndw, struct nv50_wndw_atom *asyw,
>         if (ret || !asyh->curs.visible)
>                 return ret;
>
> -       if (asyw->image.w != asyw->image.h)
> +       if (asyw->image.w != asyw->image.h) {
> +               drm_dbg_atomic(dev,
> +                              "Invalid cursor image size: width (%d) must match height (%d)",
> +                              asyw->image.w, asyw->image.h);
>                 return -EINVAL;
> +       }
> +       if (asyw->image.w > dev->mode_config.cursor_width ||
> +           asyw->image.h > dev->mode_config.cursor_height) {
> +               drm_dbg_atomic(dev,
> +                              "Invalid cursor image size: too large (%dx%d > %dx%d)",
> +                              asyw->image.w, asyw->image.h,
> +                              dev->mode_config.cursor_width,
> +                              dev->mode_config.cursor_height);
> +               return -EINVAL;
> +       }
> +       if (asyw->image.pitch[0] != asyw->image.w * 4) {

Rather than hard-coding to 4, make this look at the format (or cpp,
which should be available somewhere too I think). (Yeah, currently we
only expose RGBA8, but we should also be doing RGB5A1.)

> +               drm_dbg_atomic(dev,
> +                              "Invalid cursor image pitch: image must be packed (pitch = %d, width = %d)",
> +                              asyw->image.pitch[0], asyw->image.w);
> +               return -EINVAL;
> +       }
>
>         ret = head->func->curs_layout(head, asyw, asyh);

And this will fail due to the width/height not being supported, right?

  -ilia