[Intel-gfx] [PATCH v2 6/9] drm/i915: Round up when calculating display bandwidth requirements

[Lisovskiy, Stanislav]

On Thu, Mar 03, 2022 at 09:12:04PM +0200, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> We should round up when doing bandwidth calculations to make sure
> our estimates don't fall short of the actual number.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_bw.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
> index df98b1d7a6f7..0759bb95ea4b 100644
> --- a/drivers/gpu/drm/i915/display/intel_bw.c
> +++ b/drivers/gpu/drm/i915/display/intel_bw.c
> @@ -638,7 +638,7 @@ static unsigned int intel_bw_data_rate(struct drm_i915_private *dev_priv,
>  		data_rate += bw_state->data_rate[pipe];
>  
>  	if (DISPLAY_VER(dev_priv) >= 13 && intel_vtd_active(dev_priv))
> -		data_rate = data_rate * 105 / 100;
> +		data_rate = DIV_ROUND_UP(data_rate * 105, 100);
>  
>  	return data_rate;
>  }
> @@ -763,7 +763,7 @@ int intel_bw_calc_min_cdclk(struct intel_atomic_state *state)
>  		}
>  	}
>  
> -	new_bw_state->min_cdclk = max_bw / 64;
> +	new_bw_state->min_cdclk = DIV_ROUND_UP(max_bw, 64);
>  
>  	if (new_bw_state->min_cdclk != old_bw_state->min_cdclk) {
>  		int ret = intel_atomic_lock_global_state(&new_bw_state->base);
> -- 
> 2.34.1
>