[Intel-gfx] [PATCH v5 5/5] drm/i915/psr/bdw+: Enable CRC check in the static frame on the sink side

[Dhinakaran Pandiyan]

On Fri, 2018-06-15 at 16:03 -0700, José Roberto de Souza wrote:
> 
> Sink can be configured to calculate the CRC over the static frame and
> compare with the CRC calculated and transmited in the VSC SDP by
> source, if there is a mismatch sink will do a short pulse in HPD
> and set DP_PSR_LINK_CRC_ERROR in DP_PSR_ERROR_STATUS.
> 
> Spec: 7723
> 
> v4:
> patch moved to after 'drm/i915/psr: Avoid PSR exit max time timeout'
> to avoid touch in 2 patches EDP_PSR_DEBUG.
> 
> v3:
> disabling PSR instead of exiting on error
> 
> Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_reg.h  | 1 +
>  drivers/gpu/drm/i915/intel_psr.c | 7 ++++++-
>  2 files changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_reg.h
> b/drivers/gpu/drm/i915/i915_reg.h
> index b8c0ebd50889..11726ef0c0b6 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -4038,6 +4038,7 @@ enum {
>  #define   EDP_PSR_SKIP_AUX_EXIT			(1<<12)
>  #define   EDP_PSR_TP1_TP2_SEL			(0<<11)
>  #define   EDP_PSR_TP1_TP3_SEL			(1<<11)
> +#define   EDP_PSR_CRC_ENABLE			(1<<10) /* BDW+
> */
>  #define   EDP_PSR_TP2_TP3_TIME_500us		(0<<8)
>  #define   EDP_PSR_TP2_TP3_TIME_100us		(1<<8)
>  #define   EDP_PSR_TP2_TP3_TIME_2500us		(2<<8)
> diff --git a/drivers/gpu/drm/i915/intel_psr.c
> b/drivers/gpu/drm/i915/intel_psr.c
> index be4611963044..3b045156b2c0 100644
> --- a/drivers/gpu/drm/i915/intel_psr.c
> +++ b/drivers/gpu/drm/i915/intel_psr.c
> @@ -360,6 +360,8 @@ static void hsw_psr_enable_sink(struct intel_dp
> *intel_dp)
>  
>  	if (dev_priv->psr.link_standby)
>  		dpcd_val |= DP_PSR_MAIN_LINK_ACTIVE;
> +	if (!dev_priv->psr.psr2_enabled && INTEL_GEN(dev_priv) >= 8)
> +		dpcd_val |= DP_PSR_CRC_VERIFICATION;
>  	drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG, dpcd_val);
>  
>  	drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER,
> DP_SET_POWER_D0);
> @@ -415,6 +417,9 @@ static void hsw_activate_psr1(struct intel_dp
> *intel_dp)
>  	else
>  		val |= EDP_PSR_TP1_TP2_SEL;
>  
> +	if (INTEL_GEN(dev_priv) >= 8)
> +		val |= EDP_PSR_CRC_ENABLE;
> +
>  	val |= I915_READ(EDP_PSR_CTL) &
> EDP_PSR_RESTORE_PSR_ACTIVE_CTX_MASK;
>  	I915_WRITE(EDP_PSR_CTL, val);
>  }
> @@ -1051,7 +1056,7 @@ void intel_psr_short_pulse(struct intel_dp
> *intel_dp)
This comment change doesn't look like it belongs here.

I also think you could have left the check for LINK_CRC_ERROR in this
this patch. Anyway, the series looks good overall 

Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com> for
the series.

When resending this patch, please consider removing "bdw+" from the
title as "drm/i915/psr" is a sufficient and consistent prefix.


> 
>  	/* clear status register */
>  	drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_ERROR_STATUS,
> val);
>  
> -	/* TODO: handle other PSR/PSR2 errors */
> +	/* TODO: handle PSR2 errors */
>  exit:
>  	mutex_unlock(&psr->lock);
>  }