[PATCH v2 19/25] drm/i915/xe2hpd: Do not program MBUS_DBOX BW credits

[Matt Roper]

On Wed, Apr 03, 2024 at 04:52:47PM +0530, Balasubramani Vivekanandan wrote:
> From: José Roberto de Souza <jose.souza at intel.com>
> 
> Xe2_HPD doesn't have DBOX BW credits, so here programing it with
> zero.
> 
> BSpec: 49213
> Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan at intel.com>
> ---
>  drivers/gpu/drm/i915/display/skl_watermark.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
> index bc341abcab2f..22ae782e89f4 100644
> --- a/drivers/gpu/drm/i915/display/skl_watermark.c
> +++ b/drivers/gpu/drm/i915/display/skl_watermark.c
> @@ -3733,7 +3733,7 @@ void intel_mbus_dbox_update(struct intel_atomic_state *state)
>  		if (!new_crtc_state->hw.active)
>  			continue;
>  
> -		if (DISPLAY_VER(i915) >= 14) {
> +		if (DISPLAY_VER(i915) >= 14 && !IS_BATTLEMAGE(i915)) {

It looks like the "BW Credits" field from MBUS_DBOX_CTL doesn't exist on
any platform past Xe_LPD+.  I.e., it isn't there on Xe2_LPD (version 20)
either.  So we should probably make this block an exact match on version
14.0 only.

        if (DISPLAY_VER_FULL(i915) == IP_VER(14, 0))

so that it doesn't execute on anything else.


Matt

>  			if (xelpdp_is_only_pipe_per_dbuf_bank(crtc->pipe,
>  							      new_dbuf_state->active_pipes))
>  				pipe_val |= MBUS_DBOX_BW_8CREDITS_MTL;
> -- 
> 2.25.1
> 

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