Re: [PATCH 08/10] drm/i915: Centralize the SKL DDI A/E vs. B/C/D buf trans handling

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Oct 16, 2017 at 05:57:03PM +0300, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> 
> SKL DDI B/C/D only have 9 usable buf trans registers for DP/eDP. That
> matches the normal DP buf trans tables, but the low vswing eDP tables
> have 10 entries. Thus the eDP tables can only be used safely with DDI A
> and E.
> 
> We try to catch cases where DDI B/C/D gets used with the wrong number of
> entires in some parts of the code, but not everywhere. Let's move the
> code to deal with that deeper into intel_ddi_get_buf_trans_edp(). And
> for sake of symmetry do the same in intel_ddi_get_buf_trans_dp(). That
> would also avoid explosions in the rather unlikely case that the DP
> tables would get revised to 10 entries as well.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>

Reviewed-by: James Ausmus <james.ausmus@xxxxxxxxx>

> ---
>  drivers/gpu/drm/i915/intel_ddi.c | 60 +++++++++++++++++++++++-----------------
>  1 file changed, 34 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
> index 3bce6bddeaa9..f0a709b66e00 100644
> --- a/drivers/gpu/drm/i915/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/intel_ddi.c
> @@ -587,14 +587,29 @@ skl_get_buf_trans_hdmi(struct drm_i915_private *dev_priv, int *n_entries)
>  	}
>  }
>  
> +static int skl_buf_trans_num_entries(enum port port, int n_entries)
> +{
> +	/* Only DDIA and DDIE can select the 10th register with DP */
> +	if (port == PORT_A || port == PORT_E)
> +		return min(n_entries, 10);
> +	else
> +		return min(n_entries, 9);
> +}
> +
>  static const struct ddi_buf_trans *
>  intel_ddi_get_buf_trans_dp(struct drm_i915_private *dev_priv,
> -			   int *n_entries)
> +			   enum port port, int *n_entries)
>  {
>  	if (IS_KABYLAKE(dev_priv) || IS_COFFEELAKE(dev_priv)) {
> -		return kbl_get_buf_trans_dp(dev_priv, n_entries);
> +		const struct ddi_buf_trans *ddi_translations =
> +			kbl_get_buf_trans_dp(dev_priv, n_entries);
> +		*n_entries = skl_buf_trans_num_entries(port, *n_entries);
> +		return ddi_translations;
>  	} else if (IS_SKYLAKE(dev_priv)) {
> -		return skl_get_buf_trans_dp(dev_priv, n_entries);
> +		const struct ddi_buf_trans *ddi_translations =
> +			skl_get_buf_trans_dp(dev_priv, n_entries);
> +		*n_entries = skl_buf_trans_num_entries(port, *n_entries);
> +		return ddi_translations;
>  	} else if (IS_BROADWELL(dev_priv)) {
>  		*n_entries = ARRAY_SIZE(bdw_ddi_translations_dp);
>  		return  bdw_ddi_translations_dp;
> @@ -609,10 +624,13 @@ intel_ddi_get_buf_trans_dp(struct drm_i915_private *dev_priv,
>  
>  static const struct ddi_buf_trans *
>  intel_ddi_get_buf_trans_edp(struct drm_i915_private *dev_priv,
> -			    int *n_entries)
> +			    enum port port, int *n_entries)
>  {
>  	if (IS_GEN9_BC(dev_priv)) {
> -		return skl_get_buf_trans_edp(dev_priv, n_entries);
> +		const struct ddi_buf_trans *ddi_translations =
> +			skl_get_buf_trans_edp(dev_priv, n_entries);
> +		*n_entries = skl_buf_trans_num_entries(port, *n_entries);
> +		return ddi_translations;
>  	} else if (IS_BROADWELL(dev_priv)) {
>  		return bdw_get_buf_trans_edp(dev_priv, n_entries);
>  	} else if (IS_HASWELL(dev_priv)) {
> @@ -801,11 +819,11 @@ static void intel_prepare_dp_ddi_buffers(struct intel_encoder *encoder)
>  
>  	switch (encoder->type) {
>  	case INTEL_OUTPUT_EDP:
> -		ddi_translations = intel_ddi_get_buf_trans_edp(dev_priv,
> +		ddi_translations = intel_ddi_get_buf_trans_edp(dev_priv, port,
>  							       &n_entries);
>  		break;
>  	case INTEL_OUTPUT_DP:
> -		ddi_translations = intel_ddi_get_buf_trans_dp(dev_priv,
> +		ddi_translations = intel_ddi_get_buf_trans_dp(dev_priv, port,
>  							      &n_entries);
>  		break;
>  	case INTEL_OUTPUT_ANALOG:
> @@ -817,16 +835,10 @@ static void intel_prepare_dp_ddi_buffers(struct intel_encoder *encoder)
>  		return;
>  	}
>  
> -	if (IS_GEN9_BC(dev_priv)) {
> -		/* If we're boosting the current, set bit 31 of trans1 */
> -		if (dev_priv->vbt.ddi_port_info[port].dp_boost_level)
> -			iboost_bit = DDI_BUF_BALANCE_LEG_ENABLE;
> -
> -		if (WARN_ON(encoder->type == INTEL_OUTPUT_EDP &&
> -			    port != PORT_A && port != PORT_E &&
> -			    n_entries > 9))
> -			n_entries = 9;
> -	}
> +	/* If we're boosting the current, set bit 31 of trans1 */
> +	if (IS_GEN9_BC(dev_priv) &&
> +	    dev_priv->vbt.ddi_port_info[port].dp_boost_level)
> +		iboost_bit = DDI_BUF_BALANCE_LEG_ENABLE;
>  
>  	for (i = 0; i < n_entries; i++) {
>  		I915_WRITE(DDI_BUF_TRANS_LO(port, i),
> @@ -1831,14 +1843,9 @@ static void skl_ddi_set_iboost(struct intel_encoder *encoder,
>  		if (type == INTEL_OUTPUT_HDMI)
>  			ddi_translations = intel_ddi_get_buf_trans_hdmi(dev_priv, &n_entries);
>  		else if (type == INTEL_OUTPUT_EDP)
> -			ddi_translations = intel_ddi_get_buf_trans_edp(dev_priv, &n_entries);
> +			ddi_translations = intel_ddi_get_buf_trans_edp(dev_priv, port, &n_entries);
>  		else
> -			ddi_translations = intel_ddi_get_buf_trans_dp(dev_priv, &n_entries);
> -
> -		if (WARN_ON(type != INTEL_OUTPUT_HDMI &&
> -			    port != PORT_A &&
> -			    port != PORT_E && n_entries > 9))
> -			n_entries = 9;
> +			ddi_translations = intel_ddi_get_buf_trans_dp(dev_priv, port, &n_entries);
>  
>  		iboost = ddi_translations[level].i_boost;
>  	}
> @@ -1880,6 +1887,7 @@ static void bxt_ddi_vswing_sequence(struct intel_encoder *encoder,
>  u8 intel_ddi_dp_voltage_max(struct intel_encoder *encoder)
>  {
>  	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> +	enum port port = encoder->port;
>  	int n_entries;
>  
>  	if (IS_CANNONLAKE(dev_priv)) {
> @@ -1894,9 +1902,9 @@ u8 intel_ddi_dp_voltage_max(struct intel_encoder *encoder)
>  			bxt_get_buf_trans_dp(dev_priv, &n_entries);
>  	} else {
>  		if (encoder->type == INTEL_OUTPUT_EDP)
> -			intel_ddi_get_buf_trans_edp(dev_priv, &n_entries);
> +			intel_ddi_get_buf_trans_edp(dev_priv, port, &n_entries);
>  		else
> -			intel_ddi_get_buf_trans_dp(dev_priv, &n_entries);
> +			intel_ddi_get_buf_trans_dp(dev_priv, port, &n_entries);
>  	}
>  
>  	if (WARN_ON(n_entries < 1))
> -- 
> 2.13.6
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx




[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]
  Powered by Linux