Re: [Intel-gfx] [PATCH v4] drm/i915/display: Increase AUX timeout for Type-C

[Imre Deak <imre.deak@intel.com>]

On Tue, Apr 18, 2023 at 04:24:54PM +0530, Suraj Kandpal wrote:
> Type-C PHYs are taking longer than expected for Aux IO Power Enabling.
> Workaround: Increase the timeout.
> 
> ---v2
> -change style on how we mention WA [Ankit]
> -fix bat error by creating new func that is only called for aux power
> well scenarios so we can avoid null pointer error as it is called
> everywhere.
> 
> --v3
> -Add non-default enable_timeout to power well descriptor which avoids
> adding more platform checks [Imre]
> 
> --v4
> -Remove Bspec link from top to bottom remove WA link from commit put it
> on comment [Jani]
> -enable_timeout in ms and add .fixed_enable_delay too [Imre]
> 
> Bspec: 55480
> 
> Cc: Jani Nikula <jani.nikula@intel.com>
> Cc: Imre Deak <imre.deak@intel.com>
> Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
> ---
>  .../gpu/drm/i915/display/intel_display_power_map.c    | 11 +++++++++++
>  .../gpu/drm/i915/display/intel_display_power_well.c   |  3 ++-
>  .../gpu/drm/i915/display/intel_display_power_well.h   |  2 ++
>  3 files changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display_power_map.c b/drivers/gpu/drm/i915/display/intel_display_power_map.c
> index 6645eb1911d8..f0d51a30430a 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_power_map.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_power_map.c
> @@ -1385,6 +1385,17 @@ static const struct i915_power_well_desc xelpd_power_wells_main[] = {
>  		),
>  		.ops = &icl_aux_power_well_ops,
>  		.fixed_enable_delay = true,
> +	}, {
> +		.instances = &I915_PW_INSTANCES(
> +			I915_PW("AUX_USBC1", &tgl_pwdoms_aux_usbc1, .hsw.idx = TGL_PW_CTL_IDX_AUX_TC1),
> +			I915_PW("AUX_USBC2", &tgl_pwdoms_aux_usbc2, .hsw.idx = TGL_PW_CTL_IDX_AUX_TC2),
> +			I915_PW("AUX_USBC3", &tgl_pwdoms_aux_usbc3, .hsw.idx = TGL_PW_CTL_IDX_AUX_TC3),
> +			I915_PW("AUX_USBC4", &tgl_pwdoms_aux_usbc4, .hsw.idx = TGL_PW_CTL_IDX_AUX_TC4),
> +		),

Instead of duplicating the above 4 power wells the change should move
them to this group, as in the diff I provided.

> +		.ops = &icl_aux_power_well_ops,
> +		.fixed_enable_delay = true,
> +		/* WA_14017248603: adlp */
> +		.enable_timeout = 500,
>  	}, {
>  		.instances = &I915_PW_INSTANCES(
>  			I915_PW("AUX_TBT1", &icl_pwdoms_aux_tbt1, .hsw.idx = TGL_PW_CTL_IDX_AUX_TBT1),
> diff --git a/drivers/gpu/drm/i915/display/intel_display_power_well.c b/drivers/gpu/drm/i915/display/intel_display_power_well.c
> index 62bafcbc7937..930a42c825c3 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_power_well.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_power_well.c
> @@ -253,6 +253,7 @@ static void hsw_wait_for_power_well_enable(struct drm_i915_private *dev_priv,
>  {
>  	const struct i915_power_well_regs *regs = power_well->desc->ops->regs;
>  	int pw_idx = i915_power_well_instance(power_well)->hsw.idx;
> +	int timeout = power_well->desc->enable_timeout ? : 1;
>  
>  	/*
>  	 * For some power wells we're not supposed to watch the status bit for
> @@ -266,7 +267,7 @@ static void hsw_wait_for_power_well_enable(struct drm_i915_private *dev_priv,
>  
>  	/* Timeout for PW1:10 us, AUX:not specified, other PWs:20 us. */
>  	if (intel_de_wait_for_set(dev_priv, regs->driver,
> -				  HSW_PWR_WELL_CTL_STATE(pw_idx), 1)) {
> +				  HSW_PWR_WELL_CTL_STATE(pw_idx), timeout)) {
>  		drm_dbg_kms(&dev_priv->drm, "%s power well enable timeout\n",
>  			    intel_power_well_name(power_well));
>  
> diff --git a/drivers/gpu/drm/i915/display/intel_display_power_well.h b/drivers/gpu/drm/i915/display/intel_display_power_well.h
> index ba7cb977e7c7..e494df379e6c 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_power_well.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_power_well.h
> @@ -110,6 +110,8 @@ struct i915_power_well_desc {
>  	 * Thunderbolt mode.
>  	 */
>  	u16 is_tc_tbt:1;
> +	/* Enable timeout if greater than the default 1ms */
> +	u16 enable_timeout;
>  };
>  
>  struct i915_power_well {
> -- 
> 2.25.1
>