[Intel-gfx] [PATCH 1/3] drm/i915/display: move vbt check to intel_ddi_init()

[Lucas De Marchi]

On Mon, Feb 15, 2021 at 12:35:50PM +0200, Jani Nikula wrote:
>On Sat, 13 Feb 2021, Lucas De Marchi <lucas.demarchi at intel.com> wrote:
>> On intel_ddi_init() we already check VBT if the port supports HDMI/DP
>> and bail out otherwise. Instad of checking if a single port is present
>> using VBT in intel_display.c, move the stronger check to
>> intel_ddi_init() and return early in case it's not supported.  There
>> would be no way intel_bios_* would report support for hdmi/dp if the
>> port isn't present so this should cause no regressions for other
>> platforms.
>
>Sorry, but this will regress machines that have no VBT.

I missed that init_vbt_missing_defaults() also sets
the supports_*.

>
>I've been thinking about creating fake child devices for that case to
>reduce the exceptions.

Adding a fake child would indeed be a good option. Are you going to
implement that soon or should I?

thanks
Lucas De Marchi

>
>BR,
>Jani.
>
>
>
>>
>> Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
>> ---
>>  drivers/gpu/drm/i915/display/intel_ddi.c     |  7 +++++++
>>  drivers/gpu/drm/i915/display/intel_display.c | 14 ++++++--------
>>  2 files changed, 13 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
>> index 3b97c0091812..1235be0ba5d1 100644
>> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
>> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
>> @@ -3972,6 +3972,13 @@ void intel_ddi_init(struct drm_i915_private *dev_priv, enum port port)
>>  	bool init_hdmi, init_dp;
>>  	enum phy phy = intel_port_to_phy(dev_priv, port);
>>
>> +	if (!intel_bios_is_port_present(dev_priv, port)) {
>> +		drm_dbg_kms(&dev_priv->drm,
>> +			    "VBT says port %c is not present, respect it\n",
>> +			    port_name(port));
>> +		return;
>> +	}
>> +
>>  	/*
>>  	 * On platforms with HTI (aka HDPORT), if it's enabled at boot it may
>>  	 * have taken over some of the PHYs and made them unavailable to the
>> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
>> index 23ec68498800..7aaf7a29d493 100644
>> --- a/drivers/gpu/drm/i915/display/intel_display.c
>> +++ b/drivers/gpu/drm/i915/display/intel_display.c
>> @@ -11904,13 +11904,13 @@ static void intel_setup_outputs(struct drm_i915_private *dev_priv)
>>  		intel_ddi_init(dev_priv, PORT_C);
>>  		intel_ddi_init(dev_priv, PORT_D);
>>  		intel_ddi_init(dev_priv, PORT_E);
>> +
>>  		/*
>> -		 * On some ICL SKUs port F is not present. No strap bits for
>> -		 * this, so rely on VBT.
>> -		 * Work around broken VBTs on SKUs known to have no port F.
>> +		 * On some ICL SKUs port F is not present, but broken VBTs mark
>> +		 * the port as present. Only try to initialize port F for the
>> +		 * SKUs that may actually have it.
>>  		 */
>> -		if (IS_ICL_WITH_PORT_F(dev_priv) &&
>> -		    intel_bios_is_port_present(dev_priv, PORT_F))
>> +		if (IS_ICL_WITH_PORT_F(dev_priv))
>>  			intel_ddi_init(dev_priv, PORT_F);
>>
>>  		icl_dsi_init(dev_priv);
>> @@ -11964,10 +11964,8 @@ static void intel_setup_outputs(struct drm_i915_private *dev_priv)
>>  		/*
>>  		 * On SKL we don't have a way to detect DDI-E so we rely on VBT.
>>  		 */
>> -		if (IS_GEN9_BC(dev_priv) &&
>> -		    intel_bios_is_port_present(dev_priv, PORT_E))
>> +		if (IS_GEN9_BC(dev_priv))
>>  			intel_ddi_init(dev_priv, PORT_E);
>> -
>>  	} else if (HAS_PCH_SPLIT(dev_priv)) {
>>  		int found;
>
>-- 
>Jani Nikula, Intel Open Source Graphics Center