Re: [Intel-gfx] [PATCH 04/13] drm/i915: Read DRRS MSA timing delay from VBT

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

On Thu, 10 Mar 2022, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> VBT hsa a field for the MSA timing delay, which supposedly
> should be used with DRRS. Extract the data from the VBT.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

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

> ---
>  drivers/gpu/drm/i915/display/intel_bios.c | 3 +++
>  drivers/gpu/drm/i915/i915_drv.h           | 5 +++--
>  2 files changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
> index a559a1914588..93dc32fb3e40 100644
> --- a/drivers/gpu/drm/i915/display/intel_bios.c
> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
> @@ -888,6 +888,9 @@ parse_edp(struct drm_i915_private *i915, const struct bdb_header *bdb)
>  			i915->vbt.edp.low_vswing = vswing == 0;
>  		}
>  	}
> +
> +	i915->vbt.edp.drrs_msa_timing_delay =
> +		(edp->sdrrs_msa_timing_delay >> (panel_type * 2)) & 3;
>  }
>  
>  static void
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 943267393ecb..020c5f7602a2 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -356,10 +356,11 @@ struct intel_vbt_data {
>  		int lanes;
>  		int preemphasis;
>  		int vswing;
> -		bool low_vswing;
> -		bool initialized;
>  		int bpp;
>  		struct edp_power_seq pps;
> +		u8 drrs_msa_timing_delay;
> +		bool low_vswing;
> +		bool initialized;
>  		bool hobl;
>  	} edp;

-- 
Jani Nikula, Intel Open Source Graphics Center