Re: [Intel-gfx] [PATCH 3/3] drm/i915/bios: Introduce panel_bits() and panel_bool()

[Jani Nikula <jani.nikula@linux.intel.com>]

On Wed, 15 Jun 2022, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Abstract the bit extraction from the VBT per-panel bitfields
> slightly.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_bios.c     | 31 +++++++++++++------
>  drivers/gpu/drm/i915/display/intel_vbt_defs.h |  3 --
>  2 files changed, 21 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
> index 807184fd5618..76e86358adb9 100644
> --- a/drivers/gpu/drm/i915/display/intel_bios.c
> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
> @@ -743,6 +743,16 @@ static int get_panel_type(struct drm_i915_private *i915,
>  	return panel_types[i].panel_type;
>  }
>  
> +static unsigned int panel_bits(unsigned int value, int panel_type, int num_bits)
> +{
> +	return (value >> (panel_type * num_bits)) & (BIT(num_bits) - 1);

Nitpick, this might be easier to parse with GENMASK and friends, but
*shrug*.

Reviewed-by: Jani Nikula <jani.nikula@intel.com>


> +}
> +
> +static bool panel_bool(unsigned int value, int panel_type)
> +{
> +	return panel_bits(value, panel_type, 1);
> +}
> +
>  /* Parse general panel options */
>  static void
>  parse_panel_options(struct drm_i915_private *i915,
> @@ -766,8 +776,8 @@ parse_panel_options(struct drm_i915_private *i915,
>  	if (get_blocksize(lvds_options) < 16)
>  		return;
>  
> -	drrs_mode = (lvds_options->dps_panel_type_bits
> -				>> (panel_type * 2)) & MODE_MASK;
> +	drrs_mode = panel_bits(lvds_options->dps_panel_type_bits,
> +			       panel_type, 2);
>  	/*
>  	 * VBT has static DRRS = 0 and seamless DRRS = 2.
>  	 * The below piece of code is required to adjust vbt.drrs_type
> @@ -1313,7 +1323,7 @@ parse_power_conservation_features(struct drm_i915_private *i915,
>  	if (!power)
>  		return;
>  
> -	panel->vbt.psr.enable = power->psr & BIT(panel_type);
> +	panel->vbt.psr.enable = panel_bool(power->psr, panel_type);
>  
>  	/*
>  	 * If DRRS is not supported, drrs_type has to be set to 0.
> @@ -1321,22 +1331,23 @@ parse_power_conservation_features(struct drm_i915_private *i915,
>  	 * static DRRS is 0 and DRRS not supported is represented by
>  	 * power->drrs & BIT(panel_type)=false
>  	 */
> -	if (!(power->drrs & BIT(panel_type)) && panel->vbt.drrs_type != DRRS_TYPE_NONE) {
> +	if (!panel_bool(power->drrs, panel_type) && panel->vbt.drrs_type != DRRS_TYPE_NONE) {
>  		/*
>  		 * FIXME Should DMRRS perhaps be treated as seamless
>  		 * but without the automatic downclocking?
>  		 */
> -		if (power->dmrrs & BIT(panel_type))
> +		if (panel_bool(power->dmrrs, panel_type))
>  			panel->vbt.drrs_type = DRRS_TYPE_STATIC;
>  		else
>  			panel->vbt.drrs_type = DRRS_TYPE_NONE;
>  	}
>  
>  	if (i915->vbt.version >= 232)
> -		panel->vbt.edp.hobl = power->hobl & BIT(panel_type);
> +		panel->vbt.edp.hobl = panel_bool(power->hobl, panel_type);
>  
>  	if (i915->vbt.version >= 233)
> -		panel->vbt.vrr = power->vrr_feature_enabled & BIT(panel_type);
> +		panel->vbt.vrr = panel_bool(power->vrr_feature_enabled,
> +					    panel_type);
>  }
>  
>  static void
> @@ -1352,7 +1363,7 @@ parse_edp(struct drm_i915_private *i915,
>  	if (!edp)
>  		return;
>  
> -	switch ((edp->color_depth >> (panel_type * 2)) & 3) {
> +	switch (panel_bits(edp->color_depth, panel_type, 2)) {
>  	case EDP_18BPP:
>  		panel->vbt.edp.bpp = 18;
>  		break;
> @@ -1463,7 +1474,7 @@ parse_edp(struct drm_i915_private *i915,
>  	}
>  
>  	panel->vbt.edp.drrs_msa_timing_delay =
> -		(edp->sdrrs_msa_timing_delay >> (panel_type * 2)) & 3;
> +		panel_bits(edp->sdrrs_msa_timing_delay, panel_type, 2);
>  
>  	if (i915->vbt.version >= 244)
>  		panel->vbt.edp.max_link_rate =
> @@ -1546,7 +1557,7 @@ parse_psr(struct drm_i915_private *i915,
>  	if (i915->vbt.version >= 226) {
>  		u32 wakeup_time = psr->psr2_tp2_tp3_wakeup_time;
>  
> -		wakeup_time = (wakeup_time >> (2 * panel_type)) & 0x3;
> +		wakeup_time = panel_bits(wakeup_time, panel_type, 2);
>  		switch (wakeup_time) {
>  		case 0:
>  			wakeup_time = 500;
> diff --git a/drivers/gpu/drm/i915/display/intel_vbt_defs.h b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> index f8e5097222f2..3766c09bd65d 100644
> --- a/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> +++ b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> @@ -704,9 +704,6 @@ struct bdb_edp {
>   * Block 40 - LFP Data Block
>   */
>  
> -/* Mask for DRRS / Panel Channel / SSC / BLT control bits extraction */
> -#define MODE_MASK		0x3
> -
>  struct bdb_lvds_options {
>  	u8 panel_type;
>  	u8 panel_type2;						/* 212 */

-- 
Jani Nikula, Intel Open Source Graphics Center