[Intel-gfx] [PATCH 3/6] drm/i915: protect access to DP_TP_* on non-dp

[Matt Roper]

On Wed, Sep 04, 2019 at 02:34:16PM -0700, José Roberto de Souza wrote:
> From: Lucas De Marchi <lucas.demarchi at intel.com>
> 
> DP_TP_{CTL,STATUS} should only be programmed when the encoder is intel_dp.
> Checking its current usages intel_disable_ddi_buf() is the only
> offender, with other places being protected by checks like
> pipe_config->fec_enable that is only set by intel_dp.
> 
> v3 (José):
> - Using intel_crtc_has_dp_encoder() instead of intel_encoder_is_dp()
> (Ville)
> 
> Cc: Matt Roper <matthew.d.roper at intel.com>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>

Reviewed-by: Matt Roper <matthew.d.roper at intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_ddi.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index 1fe0bf01e580..ec132cd6add8 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -3465,10 +3465,12 @@ static void intel_disable_ddi_buf(struct intel_encoder *encoder,
>  		wait = true;
>  	}
>  
> -	val = I915_READ(DP_TP_CTL(port));
> -	val &= ~(DP_TP_CTL_ENABLE | DP_TP_CTL_LINK_TRAIN_MASK);
> -	val |= DP_TP_CTL_LINK_TRAIN_PAT1;
> -	I915_WRITE(DP_TP_CTL(port), val);
> +	if (intel_crtc_has_dp_encoder(crtc_state)) {
> +		val = I915_READ(DP_TP_CTL(port));
> +		val &= ~(DP_TP_CTL_ENABLE | DP_TP_CTL_LINK_TRAIN_MASK);
> +		val |= DP_TP_CTL_LINK_TRAIN_PAT1;
> +		I915_WRITE(DP_TP_CTL(port), val);
> +	}
>  
>  	/* Disable FEC in DP Sink */
>  	intel_ddi_disable_fec_state(encoder, crtc_state);
> -- 
> 2.23.0
> 

-- 
Matt Roper
Graphics Software Engineer
VTT-OSGC Platform Enablement
Intel Corporation
(916) 356-2795