Re: [Intel-gfx] [PATCH 2/2] drivers/drm/i915: Honor limits->max_bpp while computing DSC max input bpp

[Jani Nikula <jani.nikula@linux.intel.com>]

On Wed, 23 Aug 2023, Ankit Nautiyal <ankit.k.nautiyal@intel.com> wrote:
> Edid specific BPC constraints are stored in limits->max_bpp. Honor these
> limits while computing the input bpp for DSC.
>
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 5b48bfe09d0e..2a7f6cfe2832 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -2061,9 +2061,11 @@ static int intel_edp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,
>  	if (forced_bpp) {
>  		pipe_bpp = forced_bpp;
>  	} else {
> +		u8 max_bpc = limits->max_bpp / 3;
> +

		int max_bpc = min_t(int, limits->max_bpp / 3, conn_state->max_requested_bpc);

>  		/* For eDP use max bpp that can be supported with DSC. */
>  		pipe_bpp = intel_dp_dsc_compute_max_bpp(intel_dp, max_bbc);

Nitpick, IMO looks cleaner this way, as well as uses int instead of u8
for computations.

BR,
Jani.

>  		if (!is_dsc_pipe_bpp_sufficient(i915, conn_state, limits, pipe_bpp)) {
>  			drm_dbg_kms(&i915->drm,
>  				    "Computed BPC is not in DSC BPC limits\n");

-- 
Jani Nikula, Intel Open Source Graphics Center