Re: [PATCH 09/17] drm/i915/ddi: Unify the platform specific functions disabling a port

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

On Wed, 29 Jan 2025, Imre Deak <imre.deak@intel.com> wrote:
> The functions disabling a port for MTL+ and earlier platforms only
> differ by an extra step on MTL+ (to disable the D2D link) and the point
> at which the port's idle state is waited for. Combine the two functions
> accounting for the above differences, removing the duplication.
>
> Signed-off-by: Imre Deak <imre.deak@intel.com>

Reviewed-by: Jani Nikula <jani.nikula@intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_ddi.c | 43 ++++--------------------
>  1 file changed, 7 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index 07188606a0177..73702ccbb3773 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -3057,58 +3057,29 @@ mtl_ddi_disable_d2d_link(struct intel_encoder *encoder)
>  			port_name(port));
>  }
>  
> -static void mtl_disable_ddi_buf(struct intel_encoder *encoder,
> -				const struct intel_crtc_state *crtc_state)
> +static void intel_disable_ddi_buf(struct intel_encoder *encoder,
> +				  const struct intel_crtc_state *crtc_state)
>  {
> +	struct intel_display *display = to_intel_display(encoder);
>  	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
>  	enum port port = encoder->port;
>  
> -	/* 3.b Clear DDI_CTL_DE Enable to 0. */
>  	intel_de_rmw(dev_priv, DDI_BUF_CTL(port), DDI_BUF_CTL_ENABLE, 0);
>  
> -	/* 3.c Poll for PORT_BUF_CTL Idle Status == 1, timeout after 100us */
> -	intel_wait_ddi_buf_idle(dev_priv, port);
> +	if (DISPLAY_VER(display) >= 14)
> +		intel_wait_ddi_buf_idle(dev_priv, port);
>  
> -	/* 3.d Disable D2D Link */
>  	mtl_ddi_disable_d2d_link(encoder);
>  
> -	/* 3.e Disable DP_TP_CTL */
>  	if (intel_crtc_has_dp_encoder(crtc_state)) {
>  		intel_de_rmw(dev_priv, dp_tp_ctl_reg(encoder, crtc_state),
>  			     DP_TP_CTL_ENABLE, 0);
>  	}
> -}
> -
> -static void disable_ddi_buf(struct intel_encoder *encoder,
> -			    const struct intel_crtc_state *crtc_state)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> -	enum port port = encoder->port;
> -
> -	intel_de_rmw(dev_priv, DDI_BUF_CTL(port), DDI_BUF_CTL_ENABLE, 0);
> -
> -	if (intel_crtc_has_dp_encoder(crtc_state))
> -		intel_de_rmw(dev_priv, dp_tp_ctl_reg(encoder, crtc_state),
> -			     DP_TP_CTL_ENABLE, 0);
>  
>  	intel_ddi_disable_fec(encoder, crtc_state);
>  
> -	intel_wait_ddi_buf_idle(dev_priv, port);
> -}
> -
> -static void intel_disable_ddi_buf(struct intel_encoder *encoder,
> -				  const struct intel_crtc_state *crtc_state)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> -
> -	if (DISPLAY_VER(dev_priv) >= 14) {
> -		mtl_disable_ddi_buf(encoder, crtc_state);
> -
> -		/* 3.f Disable DP_TP_CTL FEC Enable if it is needed */
> -		intel_ddi_disable_fec(encoder, crtc_state);
> -	} else {
> -		disable_ddi_buf(encoder, crtc_state);
> -	}
> +	if (DISPLAY_VER(display) < 14)
> +		intel_wait_ddi_buf_idle(dev_priv, port);
>  
>  	intel_ddi_wait_for_fec_status(encoder, crtc_state, false);
>  }

-- 
Jani Nikula, Intel