[Intel-gfx] [PATCH] drm/i915/display: Cleanup intel_phy_is_combo()

[Matt Roper]

On Thu, Jul 21, 2022 at 01:17:54PM -0700, Anusha Srivatsa wrote:
> No functional change. Cleanup the intel_phy_is_combo

But there actually is a functional change here --- display version 14
will now (properly) fall through to the 'else' branch instead of being
picked up by the 11/12/adl branch.  I believe that was your original
motivation for this patch, so you may want to mention that in the commit
message (and drop the "no functional change" statement).

The code change itself looks fine to me since it seems like the
traditional combo PHYs may be a thing of the past and we don't want to
keep assuming future platforms will have any.


Matt

> to accommodate for cases where combo phy is not available.
> 
> v2: retain comment that explains DG2 returning false from
> intel_phy_is_combo() (Arun)
> 
> Cc: Arun R Murthy <arun.r.murthy at intel.com>
> Cc: Matt Roper <matthew.d.roper at intel.com>
> Signed-off-by: Anusha Srivatsa <anusha.srivatsa at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 14 ++++++--------
>  1 file changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index a0f84cbe974f..b9d0be7753a8 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -2082,22 +2082,20 @@ bool intel_phy_is_combo(struct drm_i915_private *dev_priv, enum phy phy)
>  {
>  	if (phy == PHY_NONE)
>  		return false;
> -	else if (IS_DG2(dev_priv))
> -		/*
> -		 * DG2 outputs labelled as "combo PHY" in the bspec use
> -		 * SNPS PHYs with completely different programming,
> -		 * hence we always return false here.
> -		 */
> -		return false;
>  	else if (IS_ALDERLAKE_S(dev_priv))
>  		return phy <= PHY_E;
>  	else if (IS_DG1(dev_priv) || IS_ROCKETLAKE(dev_priv))
>  		return phy <= PHY_D;
>  	else if (IS_JSL_EHL(dev_priv))
>  		return phy <= PHY_C;
> -	else if (DISPLAY_VER(dev_priv) >= 11)
> +	else if (IS_ALDERLAKE_P(dev_priv) || IS_DISPLAY_VER(dev_priv, 11, 12))
>  		return phy <= PHY_B;
>  	else
> +		/*
> +		 * DG2 outputs labelled as "combo PHY" in the bspec use
> +		 * SNPS PHYs with completely different programming,
> +		 * hence we always return false here.
> +		 */
>  		return false;
>  }
>  
> -- 
> 2.25.1
> 

-- 
Matt Roper
Graphics Software Engineer
VTT-OSGC Platform Enablement
Intel Corporation