[PATCH] drm/amd/display: clean-up dead code in dml2_mall_phantom

[Deucher, Alexander]

[Public]

> -----Original Message-----
> From: Brahmajit Das <listout at listout.xyz>
> Sent: Tuesday, August 19, 2025 4:42 PM
> To: Koenig, Christian <Christian.Koenig at amd.com>; Alex Deucher
> <alexdeucher at gmail.com>; Lei, Jun <Jun.Lei at amd.com>; Zhuo, Lillian
> <Qingqing.Zhuo at amd.com>; Deucher, Alexander
> <Alexander.Deucher at amd.com>
> Cc: linux-kernel at vger.kernel.org; amd-gfx at lists.freedesktop.org;
> listout at listout.xyz
> Subject: [PATCH] drm/amd/display: clean-up dead code in dml2_mall_phantom
>
> pipe_idx in function dml2_svp_validate_static_schedulabilit, although set is never
> actually used. While building with GCC 16 this gives a
> warning:
>
> drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/dml2_mall_phantom.c: In function
> ‘set_phantom_stream_timing’:
> drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/dml2_mall_phantom.c:657:25:
> warning: variable ‘pipe_idx’ set but not used [-Wunused-but-set-variable=]
>   657 |         unsigned int i, pipe_idx;
>       |                         ^~~~~~~~
>
> Signed-off-by: Brahmajit Das <listout at listout.xyz>
> ---
>  drivers/gpu/drm/amd/display/dc/dml2/dml2_mall_phantom.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/dc/dml2/dml2_mall_phantom.c
> b/drivers/gpu/drm/amd/display/dc/dml2/dml2_mall_phantom.c
> index a56e75cdf712..1d0af0f8ffa1 100644
> --- a/drivers/gpu/drm/amd/display/dc/dml2/dml2_mall_phantom.c
> +++ b/drivers/gpu/drm/amd/display/dc/dml2/dml2_mall_phantom.c
> @@ -654,14 +654,13 @@ static void set_phantom_stream_timing(struct
> dml2_context *ctx, struct dc_state
>                                    unsigned int svp_height,
>                                    unsigned int svp_vstartup)
>  {
> -     unsigned int i, pipe_idx;
>       double line_time, fp_and_sync_width_time;
>       struct pipe_ctx *pipe;
>       uint32_t phantom_vactive, phantom_bp, pstate_width_fw_delay_lines;
>       static const double cvt_rb_vblank_max = ((double) 460 / (1000 * 1000));
>
>       // Find DML pipe index (pipe_idx) using dc_pipe_idx
> -     for (i = 0, pipe_idx = 0; i < ctx->config.dcn_pipe_count; i++) {
> +     for (unsigned int i = 0; i < ctx->config.dcn_pipe_count; i++) {

Better to leave this declaration above otherwise other compilers may complain about mixed code and declarations.

Alex

>               pipe = &state->res_ctx.pipe_ctx[i];
>
>               if (!pipe->stream)
> @@ -669,8 +668,6 @@ static void set_phantom_stream_timing(struct
> dml2_context *ctx, struct dc_state
>
>               if (i == dc_pipe_idx)
>                       break;
> -
> -             pipe_idx++;
>       }
>
>       // Calculate lines required for pstate allow width and FW processing delays
> --
> 2.51.0