Re: [PATCH] drm/amd/display: Fix redundant GPUVMEnable checks in dcn6 flip schedule

On 8/20/26 6:16 AM, Srinivasan Shanmugam <[email protected]> wrote:
> Inside dcn6_calculate_flip_schedule(), GPUVMEnable is already checked in
> the outer if block. But the same GPUVMEnable is checked again in two
> inner if blocks inside it. Since GPUVMEnable is always true at that
> point, the inner else branches that assign meta_row_height are never
> reached.
> 
> Remove the redundant inner GPUVMEnable checks and directly assign
> dpte_row_height, which is always the correct value here.
> 
> Fixes: 04d9a88decbc ("drm/amd/display: Add new sources for DCN6")
> Reported-by: Dan Carpenter <[email protected]>
> Cc: Roman Li <[email protected]>
> Cc: Alex Hung <[email protected]>
> Cc: Tom Chung <[email protected]>
> Cc: Aurabindo Pillai <[email protected]>
> Signed-off-by: Srinivasan Shanmugam <[email protected]>

Reviewed-by: George Zhang <[email protected]>

> ---
>   .../src/dml2_core/dml2_core_dcn6_calcs_dchub.c    | 15 +++------------
>   1 file changed, 3 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_core/dml2_core_dcn6_calcs_dchub.c b/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_core/dml2_core_dcn6_calcs_dchub.c
> index cae6bee93fe3..a4e2f8604650 100644
> --- a/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_core/dml2_core_dcn6_calcs_dchub.c
> +++ b/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/src/dml2_core/dml2_core_dcn6_calcs_dchub.c
> @@ -569,20 +569,11 @@ void dcn6_calculate_flip_schedule(
>   
>   	if (GPUVMEnable) {
>   		if (l->dual_plane) {
> -			if (GPUVMEnable) {
> -				l->min_row_height = dpte_row_height;
> -				l->min_row_height_chroma = dpte_row_height_chroma;
> -			} else {
> -				l->min_row_height = meta_row_height;
> -				l->min_row_height_chroma = meta_row_height_chroma;
> -			}
> +			l->min_row_height = dpte_row_height;
> +			l->min_row_height_chroma = dpte_row_height_chroma;
>   			l->min_row_time = math_min2(l->min_row_height * LineTime / VRatio, l->min_row_height_chroma * LineTime / VRatioChroma);
>   		} else {
> -			if (GPUVMEnable)
> -				l->min_row_height = dpte_row_height;
> -			else
> -				l->min_row_height = meta_row_height;
> -
> +			l->min_row_height = dpte_row_height;
>   			l->min_row_time = l->min_row_height * LineTime / VRatio;
>   		}
>   		DML_LOG_VERBOSE("DML::%s: min_row_time = %f\n", __func__, l->min_row_time);
>