[PATCH v2 07/25] Revert "drm/i915/dgfx: DGFX uses direct VBT pin mapping"

[Matt Roper]

On Wed, Apr 03, 2024 at 04:52:35PM +0530, Balasubramani Vivekanandan wrote:
> From: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> 
> This reverts commit 562f33836f519a235e5c5e71bcc723ab1faccd2f.
> For BMG it seems that the VBT to DDI mapping does not follow DG1, and
> DG2, but follows ADLP mapping given in Bspec:20124.
> 
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan at intel.com>

Matches our experimental findings, so

Reviewed-by: Matt Roper <matthew.d.roper at intel.com>

I've pinged the internal ticket to try to get the documentation for this
clarified.

BTW, if you send another version of this series it might make more sense
to re-order this to be after patch #20, since that's where we define
which south display (i.e., "fake pch") is used on BMG.


Matt

> ---
>  drivers/gpu/drm/i915/display/intel_bios.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
> index 2abd2d7ceda2..03fbd6c73f3f 100644
> --- a/drivers/gpu/drm/i915/display/intel_bios.c
> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
> @@ -2238,15 +2238,14 @@ static u8 map_ddc_pin(struct drm_i915_private *i915, u8 vbt_pin)
>  	const u8 *ddc_pin_map;
>  	int i, n_entries;
>  
> -	if (IS_DGFX(i915))
> -		return vbt_pin;
> -
>  	if (INTEL_PCH_TYPE(i915) >= PCH_MTL || IS_ALDERLAKE_P(i915)) {
>  		ddc_pin_map = adlp_ddc_pin_map;
>  		n_entries = ARRAY_SIZE(adlp_ddc_pin_map);
>  	} else if (IS_ALDERLAKE_S(i915)) {
>  		ddc_pin_map = adls_ddc_pin_map;
>  		n_entries = ARRAY_SIZE(adls_ddc_pin_map);
> +	} else if (INTEL_PCH_TYPE(i915) >= PCH_DG1) {
> +		return vbt_pin;
>  	} else if (IS_ROCKETLAKE(i915) && INTEL_PCH_TYPE(i915) == PCH_TGP) {
>  		ddc_pin_map = rkl_pch_tgp_ddc_pin_map;
>  		n_entries = ARRAY_SIZE(rkl_pch_tgp_ddc_pin_map);
> -- 
> 2.25.1
> 

-- 
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation