[Intel-gfx] [PATCH] drm/i915/ehl: Check VBT before updating the transcoder for pipe

[Jani Nikula]

On Mon, 03 Feb 2020, Vivek Kasireddy <vivek.kasireddy at intel.com> wrote:
> Since the pipe->transcoder mapping is not expected to change unless
> there is either eDP or DSI connectors present, check the VBT to confirm
> their presence in addition to checking TRANS_DDI_FUNC_CTL(transcoder).
> This additional check is needed on platforms like Elkhart Lake because
> we cannot just rely on GOP/Firmware programmed values in
> TRANS_DDI_FUNC_CTL(transcoder) before updating the transcoder mapping.
>
> This patch is only relevant to EHL -- and a no-op on others --
> because some of the PHYs are shared between the different DDIs and
> we rely on the VBT to present the most accurate information to the
> driver.
>
> Cc: Matt Roper <matthew.d.roper at intel.com>
> Cc: José Roberto de Souza <jose.souza at intel.com>
> Signed-off-by: Vivek Kasireddy <vivek.kasireddy at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 15 ++++++++++++++-
>  1 file changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index c0e5002ce64c..4b38f293bd88 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -10805,6 +10805,18 @@ static void hsw_get_ddi_pll(struct drm_i915_private *dev_priv, enum port port,
>  	pipe_config->shared_dpll = intel_get_shared_dpll_by_id(dev_priv, id);
>  }
>  
> +static bool ehl_vbt_edp_dsi_present(struct drm_i915_private *dev_priv,
> +				    enum transcoder transcoder)
> +{
> +	bool edp_present = intel_bios_is_port_present(dev_priv, PORT_A);
> +	bool dsi_present = intel_bios_is_dsi_present(dev_priv, NULL);
> +
> +	if (IS_ELKHARTLAKE(dev_priv))
> +		return transcoder == TRANSCODER_EDP ? edp_present : dsi_present;
> +
> +	return true;
> +}

One of those things... this jumps out and immediately feels all wrong,
just like ehl_vbt_ddi_d_present() feels all wrong in
intel_combo_phy.c. But I don't know what would be the right thing to do
without spending time that I don't have on this.

BR,
Jani.



> +
>  static bool hsw_get_transcoder_state(struct intel_crtc *crtc,
>  				     struct intel_crtc_state *pipe_config,
>  				     u64 *power_domain_mask,
> @@ -10844,7 +10856,8 @@ static bool hsw_get_transcoder_state(struct intel_crtc *crtc,
>  
>  		tmp = intel_de_read(dev_priv,
>  				    TRANS_DDI_FUNC_CTL(panel_transcoder));
> -		if (!(tmp & TRANS_DDI_FUNC_ENABLE))
> +		if (!(tmp & TRANS_DDI_FUNC_ENABLE) ||
> +		    !ehl_vbt_edp_dsi_present(dev_priv, panel_transcoder))
>  			continue;
>  
>  		/*

-- 
Jani Nikula, Intel Open Source Graphics Center