[Nouveau] [PATCH v2] nouveau/dispnv50: add cursor pitch check

[Lyude Paul]

On Fri, 2021-02-05 at 22:00 +0100, Simon Ser wrote:
> The hardware needs a FB which is packed. Add checks to make sure
> this is the case.
> 
> While at it, add debug logs for the existing checks. This allows
> user-space to more easily figure out why a configuration is
> rejected.
> 
> v2:
> - Use drm_format_info instead of hardcoding bytes-per-pixel (Ilia)
> - Remove unnecessary size check (Ilia)
> 
> 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 | 21 +++++++++++++++++++--
>  1 file changed, 19 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/nouveau/dispnv50/curs507a.c
> b/drivers/gpu/drm/nouveau/dispnv50/curs507a.c
> index 54fbd6fe751d..00f09c9a8d15 100644
> --- a/drivers/gpu/drm/nouveau/dispnv50/curs507a.c
> +++ b/drivers/gpu/drm/nouveau/dispnv50/curs507a.c
> @@ -30,6 +30,7 @@
>  
>  #include <drm/drm_atomic_helper.h>
>  #include <drm/drm_plane_helper.h>
> +#include <drm/drm_fourcc.h>
>  
>  bool
>  curs507a_space(struct nv50_wndw *wndw)
> @@ -99,6 +100,8 @@ 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;
> +       struct drm_framebuffer *fb = asyw->state.fb;
>         int ret;
>  
>         ret = drm_atomic_helper_check_plane_state(&asyw->state, &asyh->state,
> @@ -109,12 +112,26 @@ 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.pitch[0] != asyw->image.w * fb->format->cpp[0]) {
> +               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);
> -       if (ret)
> +       if (ret) {
> +               drm_dbg_atomic(dev,
> +                              "Invalid cursor image size: unsupported size
> %dx%d",
> +                              asyw->image.w, asyw->image.h);
>                 return ret;
> +       }

Oh-some things I forgot to mention:

- You're missing some newlines in your debug messages
- Also, NV_ATOMIC() is a thing

With those two fixed:

Reviewed-by: Lyude Paul <lyude at redhat.com>

>  
>         return head->func->curs_format(head, asyw, asyh);
>  }

-- 
Sincerely,
   Lyude Paul (she/her)
   Software Engineer at Red Hat
   
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