[Intel-gfx] [PATCH] drm/i915/gen9+: Rely on VBT DDI port info for eDP detection

[David Weinehall]

On Tue, Dec 20, 2016 at 05:12:49PM +0200, Imre Deak wrote:
> There is at least one APL based system using port A in DP mode
> (connecting to an on-board DP->VGA adaptor). Atm we'll configure port A
> unconditionally as eDP which is incorrect in this case. Fix this by
> relying on the VBT DDI port 'internal port' flag instead on all ports
> GEN9 onwards. For now chicken out from doing this on earlier DDI
> platforms too.
> 
> Signed-off-by: Imre Deak <imre.deak at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.h   | 1 +
>  drivers/gpu/drm/i915/intel_bios.c | 1 +
>  drivers/gpu/drm/i915/intel_dp.c   | 3 +++
>  3 files changed, 5 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 7e94e506..42fb7e9 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1669,6 +1669,7 @@ struct ddi_vbt_port_info {
>  	uint8_t supports_dvi:1;
>  	uint8_t supports_hdmi:1;
>  	uint8_t supports_dp:1;
> +	uint8_t supports_edp:1;
>  
>  	uint8_t alternate_aux_channel;
>  	uint8_t alternate_ddc_pin;
> diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
> index 1cf2fa6..60fdd31 100644
> --- a/drivers/gpu/drm/i915/intel_bios.c
> +++ b/drivers/gpu/drm/i915/intel_bios.c
> @@ -1161,6 +1161,7 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
>  	info->supports_dvi = is_dvi;
>  	info->supports_hdmi = is_hdmi;
>  	info->supports_dp = is_dp;
> +	info->supports_edp = is_edp;
>  
>  	DRM_DEBUG_KMS("Port %c VBT info: DP:%d HDMI:%d DVI:%d EDP:%d CRT:%d\n",
>  		      port_name(port), is_dp, is_hdmi, is_dvi, is_edp, is_crt);
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index d37cb00..7f3f4fa 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -4983,6 +4983,9 @@ bool intel_dp_is_edp(struct drm_i915_private *dev_priv, enum port port)
>  	if (INTEL_GEN(dev_priv) < 5)
>  		return false;
>  
> +	if (INTEL_GEN(dev_priv) >= 9)
> +		return dev_priv->vbt.ddi_port_info[port].supports_edp;
> +

We already have intel_bios_is_port_edp() that tries to
discern whether the port is eDP or not.

Wouldn't that function be usable for this purpose?

If so, doing:

if (port == PORT_A && INTEL_GEN(dev_priv) < 9)
	return true;

return intel_bios_is_port_edp(dev_priv, port);

should be enough. If not, maybe it should be fixed instead of
introducing a new way of doing things.

>  	if (port == PORT_A)
>  		return true;


Kind regards, David