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 Thu, 24 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.
>
> v2: Use int instead of u8 for computations. (Jani)
> Add closes tag. (Ankit)
>
> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9161
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 7067ee3a4bd3..8f3dc79089ea 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -2061,9 +2061,10 @@ static int intel_edp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,
>  	if (forced_bpp) {
>  		pipe_bpp = forced_bpp;
>  	} else {
> +		int max_bpc = min(limits->max_bpp / 3, (int)conn_state->max_requested_bpc);

Hmh, only noticed after pushing, there's min_t() for when the types
differ.

BR,
Jani.

> +
>  		/* For eDP use max bpp that can be supported with DSC. */
> -		pipe_bpp = intel_dp_dsc_compute_max_bpp(intel_dp,
> -							conn_state->max_requested_bpc);
> +		pipe_bpp = intel_dp_dsc_compute_max_bpp(intel_dp, max_bpc);
>  		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