Re: [PATCH] drm/i915/vdsc: Add bpc check in intel_dsc_compute_params

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

On Thu, 26 Sep 2024, Suraj Kandpal <suraj.kandpal@intel.com> wrote:
> DSC does not support bpc under 8 according to DSC 1.2a Section 2
> Requirements. Return an error if that happens to be the case.
>
> --v2
> -should be bits_per_component [Mitul/Chaitanya/Srikanth]
> -Add reference to this restriction [Chaitanya]
>
> Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_vdsc.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
> index 8158e3702ed5..7a30fdea16da 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> @@ -306,6 +306,11 @@ int intel_dsc_compute_params(struct intel_crtc_state *pipe_config)
>  
>  	vdsc_cfg->bits_per_component = pipe_config->pipe_bpp / 3;
>  
> +	if (vdsc_cfg->bits_per_component < 8) {
> +		drm_dbg_kms(&dev_priv->drm, "DSC bpc requirements not met\n");

If you hit this warning, what's the absolutely first thing you want to
know...? Maybe log that bits_per_component value here?

BR,
Jani.

> +		return -EINVAL;
> +	}
> +
>  	drm_dsc_set_rc_buf_thresh(vdsc_cfg);
>  
>  	/*

-- 
Jani Nikula, Intel