Re: [PATCH] drm/i915/dp_mst: Disable Panel Replay

["Hogander, Jouni" <jouni.hogander@intel.com>]

On Fri, 2025-11-07 at 14:41 +0200, Imre Deak wrote:
> Disable Panel Replay on MST links until it's properly implemented.
> For
> instance the required VSC SDP is not programmed on MST and FEC is not
> enabled if Panel Replay is enabled.
> 
> Fixes: 3257e55d3ea7 ("drm/i915/panelreplay: enable/disable panel
> replay")
> Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15174
> Cc: Jouni Högander <jouni.hogander@intel.com>
> Cc: Animesh Manna <animesh.manna@intel.com>
> Cc: stable@vger.kernel.org # v6.8+
> Signed-off-by: Imre Deak <imre.deak@intel.com>

Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_psr.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> b/drivers/gpu/drm/i915/display/intel_psr.c
> index 05014ffe3ce1d..54fc30cfad84c 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -626,6 +626,10 @@ static void _panel_replay_init_dpcd(struct
> intel_dp *intel_dp)
>  	struct intel_display *display = to_intel_display(intel_dp);
>  	int ret;
>  
> +	/* TODO: Enable Panel Replay on MST once it's properly
> implemented. */
> +	if (intel_dp->mst_detect == DRM_DP_MST)
> +		return;
> +
>  	ret = drm_dp_dpcd_read_data(&intel_dp->aux,
> DP_PANEL_REPLAY_CAP_SUPPORT,
>  				    &intel_dp->pr_dpcd,
> sizeof(intel_dp->pr_dpcd));
>  	if (ret < 0)