Re: [PATCH 02/11] drm/i915/bw: Streamline dg2_get_bw_info()

["Govindapillai, Vinod" <vinod.govindapillai@intel.com>]

On Thu, 2026-05-28 at 13:34 +0300, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> Make dg2_get_bw_info() look a bit more like xe2_hpd_get_bw_info()
> so that we don't have so many different ways of writing the same
> stuff (namely the "set all plane groups to the same value" part).
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_bw.c | 22 ++++++----------------
>  1 file changed, 6 insertions(+), 16 deletions(-)
> 


Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>


> diff --git a/drivers/gpu/drm/i915/display/intel_bw.c
> b/drivers/gpu/drm/i915/display/intel_bw.c
> index d0ceffc93f36..887628144864 100644
> --- a/drivers/gpu/drm/i915/display/intel_bw.c
> +++ b/drivers/gpu/drm/i915/display/intel_bw.c
> @@ -699,25 +699,15 @@ static int tgl_get_bw_info(struct intel_display
> *display,
>  
>  static void dg2_get_bw_info(struct intel_display *display)
>  {
> -	unsigned int deratedbw = display->platform.dg2_g11 ? 38000 :
> 50000;
> -	int num_groups = ARRAY_SIZE(display->bw.max);
>  	int i;
>  
> -	/*
> -	 * DG2 doesn't have SAGV or QGV points, just a constant max
> bandwidth
> -	 * that doesn't depend on the number of planes enabled. So
> fill all the
> -	 * plane group with constant bw information for uniformity
> with other
> -	 * platforms. DG2-G10 platforms have a constant 50 GB/s
> bandwidth,
> -	 * whereas DG2-G11 platforms have 38 GB/s.
> -	 */
> -	for (i = 0; i < num_groups; i++) {
> -		struct intel_bw_info *bi = &display->bw.max[i];
> +	display->bw.max[0].deratedbw[0] = display->platform.dg2_g11
> ? 38000 : 50000;
>  
> -		bi->num_planes = 1;
> -		/* Need only one dummy QGV point per group */
> -		bi->num_qgv_points = 1;
> -		bi->deratedbw[0] = deratedbw;
> -	}
> +	/* Bandwidth does not depend on # of planes; set all groups
> the same */
> +	display->bw.max[0].num_planes = 1;
> +	display->bw.max[0].num_qgv_points = 1;
> +	for (i = 1; i < ARRAY_SIZE(display->bw.max); i++)
> +		display->bw.max[i] = display->bw.max[0];
>  
>  	display->sagv.status = I915_SAGV_NOT_CONTROLLED;
>  }