Re: [PATCH 3/3] drm/i915/display: Avoid divide by zero

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Fri, Sep 05, 2025 at 01:46:26PM +0300, Juha-Pekka Heikkila wrote:
> skl_crtc_allocate_plane_ddb allow iter.data_rate to be zero
> which could cause divide by zero in skl_allocate_plane_ddb,
> check against that.

As I said I don't think the div-by-zero is really possible. 
So should say here that this is just to shut up some static
analysis noise.

> 
> Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
> Reviewed-by: Suraj Kandpal <suraj.kandpal@intel.com>
> ---
>  drivers/gpu/drm/i915/display/skl_watermark.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
> index 33885d619a97..bfcd700b95e4 100644
> --- a/drivers/gpu/drm/i915/display/skl_watermark.c
> +++ b/drivers/gpu/drm/i915/display/skl_watermark.c
> @@ -1388,7 +1388,7 @@ skl_allocate_plane_ddb(struct skl_plane_ddb_iter *iter,
>  {
>  	u16 size, extra = 0;
>  
> -	if (data_rate) {
> +	if (data_rate && iter->data_rate) {
>  		extra = min_t(u16, iter->size,
>  			      DIV64_U64_ROUND_UP(iter->size * data_rate,
>  						 iter->data_rate));
> -- 
> 2.43.0

-- 
Ville Syrjälä
Intel