Re: [Intel-gfx] [PATCH 5/6] drm/915: Extend dual PPS handlind for ICP+

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Wed, Nov 09, 2022 at 01:16:48PM +0200, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> 
> On the PCH side the second PPS was introduced in ICP. Let's
> make sure we examine both power sequencer on ICP+ as well.
> 
> Note that DG1/2 south block only has the single PPS, so need
> to exclude the fake DG1/2 PCHs.
> 
> Cc: Animesh Manna <animesh.manna@intel.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_pps.c | 15 ++++++++++++---
>  1 file changed, 12 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_pps.c b/drivers/gpu/drm/i915/display/intel_pps.c
> index ff4f1def59d2..f3ac4eee4d39 100644
> --- a/drivers/gpu/drm/i915/display/intel_pps.c
> +++ b/drivers/gpu/drm/i915/display/intel_pps.c
> @@ -401,6 +401,15 @@ struct pps_registers {
>  	i915_reg_t pp_div;
>  };
>  
> +static bool has_dual_bxt_pps(struct drm_i915_private *i915)
> +{
> +	if (IS_GEMINILAKE(i915) || IS_BROXTON(i915))
> +		return true;
> +
> +	return INTEL_PCH_TYPE(i915) >= PCH_ICP &&
> +		INTEL_PCH_TYPE(i915) < PCH_DG1;

Apparently there is a chicken bit to switch the pin muxing
between second pps/backlight vs. some other display functions.
We should probably check that before assuming that usage of
the second pps is even possible.

> +}
> +
>  static void intel_pps_get_registers(struct intel_dp *intel_dp,
>  				    struct pps_registers *regs)
>  {
> @@ -409,7 +418,7 @@ static void intel_pps_get_registers(struct intel_dp *intel_dp,
>  
>  	memset(regs, 0, sizeof(*regs));
>  
> -	if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv))
> +	if (has_dual_bxt_pps(dev_priv))
>  		pps_idx = bxt_power_sequencer_idx(intel_dp);
>  	else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
>  		pps_idx = vlv_power_sequencer_pipe(intel_dp);
> @@ -1478,7 +1487,7 @@ void intel_pps_init(struct intel_dp *intel_dp)
>  	pps_init_timestamps(intel_dp);
>  
>  	with_intel_pps_lock(intel_dp, wakeref) {
> -		if (IS_GEMINILAKE(i915) || IS_BROXTON(i915))
> +		if (has_dual_bxt_pps(i915))
>  			bxt_initial_power_sequencer_setup(intel_dp);
>  		else if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915))
>  			vlv_initial_power_sequencer_setup(intel_dp);
> @@ -1512,7 +1521,7 @@ void intel_pps_init_late(struct intel_dp *intel_dp)
>  
>  	with_intel_pps_lock(intel_dp, wakeref) {
>  		/* Reinit delays after per-panel info has been parsed from VBT */
> -		if (IS_GEMINILAKE(i915) || IS_BROXTON(i915))
> +		if (has_dual_bxt_pps(i915))
>  			bxt_pps_init_late(intel_dp);
>  		memset(&intel_dp->pps.pps_delays, 0, sizeof(intel_dp->pps.pps_delays));
>  		pps_init_delays(intel_dp);
> -- 
> 2.37.4

-- 
Ville Syrjälä
Intel