[Intel-gfx] [PATCH 03/11] drm/i915: Disable HDCP signalling on transcoder disable

[Ville Syrjälä]

On Tue, Dec 03, 2019 at 12:36:26PM -0500, Sean Paul wrote:
> From: Sean Paul <seanpaul at chromium.org>
> 
> Currently we rely on intel_hdcp_disable() to disable HDCP signalling in
> the DDI Function Control register. This patch adds a safety net by also
> clearing the bit when we disable the transcoder.
> 
> Once we have HDCP over MST and disappearing connectors, we want to make
> sure that the signalling is truly disabled even if HDCP teardown doesn't
> go as planned.

Why wouldn't it go as planned?

> 
> Signed-off-by: Sean Paul <seanpaul at chromium.org>
> ---
>  drivers/gpu/drm/i915/display/intel_ddi.c | 13 ++++++-------
>  1 file changed, 6 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index b51f244ad7a5..e8ac98a8ee7f 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -1952,13 +1952,12 @@ void intel_ddi_disable_transcoder_func(const struct intel_crtc_state *crtc_state
>  	i915_reg_t reg = TRANS_DDI_FUNC_CTL(cpu_transcoder);
>  	u32 val = I915_READ(reg);
>  
> -	if (INTEL_GEN(dev_priv) >= 12) {
> -		val &= ~(TRANS_DDI_FUNC_ENABLE | TGL_TRANS_DDI_PORT_MASK |
> -			 TRANS_DDI_DP_VC_PAYLOAD_ALLOC);
> -	} else {
> -		val &= ~(TRANS_DDI_FUNC_ENABLE | TRANS_DDI_PORT_MASK |
> -			 TRANS_DDI_DP_VC_PAYLOAD_ALLOC);
> -	}
> +	val &= ~(TRANS_DDI_FUNC_ENABLE | TRANS_DDI_DP_VC_PAYLOAD_ALLOC |
> +		 TRANS_DDI_HDCP_SIGNALLING);
> +	if (INTEL_GEN(dev_priv) >= 12)
> +		val &= ~TGL_TRANS_DDI_PORT_MASK;
> +	else
> +		val &= ~TRANS_DDI_PORT_MASK;
>  	I915_WRITE(reg, val);
>  
>  	if (dev_priv->quirks & QUIRK_INCREASE_DDI_DISABLED_TIME &&
> -- 
> Sean Paul, Software Engineer, Google / Chromium OS
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Ville Syrjälä
Intel