Re: [Intel-gfx] [PATCH 10/11] drm/i915: Factor out call_with_modeset_ctx()

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Wed, Apr 26, 2023 at 07:53:04PM +0300, Imre Deak wrote:
> Factor out a helper to call a function with the atomic locks held,
> required by a follow-up patch resetting an active DP link.
> 
> No functional changes.
> 
> Signed-off-by: Imre Deak <imre.deak@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_ddi.c | 53 ++++++++++++++----------
>  1 file changed, 31 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index 29e4bfab46358..0c8bc32f293b0 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -4370,35 +4370,18 @@ static int intel_hdmi_reset_link(struct intel_encoder *encoder,
>  	return modeset_pipe(&crtc->base, ctx);
>  }
>  
> -static enum intel_hotplug_state
> -intel_ddi_hotplug(struct intel_encoder *encoder,
> -		  struct intel_connector *connector)
> +static void call_with_modeset_ctx(int (*fn)(struct intel_encoder *encoder,
> +					    struct drm_modeset_acquire_ctx *ctx),
> +				  struct intel_encoder *encoder)
>  {
>  	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> -	struct intel_digital_port *dig_port = enc_to_dig_port(encoder);
> -	struct intel_dp *intel_dp = &dig_port->dp;
> -	enum phy phy = intel_port_to_phy(i915, encoder->port);
> -	bool is_tc = intel_phy_is_tc(i915, phy);
>  	struct drm_modeset_acquire_ctx ctx;
> -	enum intel_hotplug_state state;
>  	int ret;
>  
> -	if (intel_dp->compliance.test_active &&
> -	    intel_dp->compliance.test_type == DP_TEST_LINK_PHY_TEST_PATTERN) {
> -		intel_dp_phy_test(encoder);
> -		/* just do the PHY test and nothing else */
> -		return INTEL_HOTPLUG_UNCHANGED;
> -	}
> -
> -	state = intel_encoder_hotplug(encoder, connector);
> -
>  	drm_modeset_acquire_init(&ctx, 0);
>  
>  	for (;;) {
> -		if (connector->base.connector_type == DRM_MODE_CONNECTOR_HDMIA)
> -			ret = intel_hdmi_reset_link(encoder, &ctx);
> -		else
> -			ret = intel_dp_retrain_link(encoder, &ctx);
> +		ret = fn(encoder, &ctx);
>  
>  		if (ret == -EDEADLK) {
>  			drm_modeset_backoff(&ctx);
> @@ -4410,8 +4393,34 @@ intel_ddi_hotplug(struct intel_encoder *encoder,
>  
>  	drm_modeset_drop_locks(&ctx);
>  	drm_modeset_acquire_fini(&ctx);
> -	drm_WARN(encoder->base.dev, ret,
> +	drm_WARN(&i915->drm, ret,
>  		 "Acquiring modeset locks failed with %i\n", ret);
> +}

Seems pretty much a less general version of
https://patchwork.freedesktop.org/series/92607/
Unfortuantely that died in the bikeshed.

Maybe we should look into doing something like that
just for i915 initially...

> +
> +static enum intel_hotplug_state
> +intel_ddi_hotplug(struct intel_encoder *encoder,
> +		  struct intel_connector *connector)
> +{
> +	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> +	struct intel_digital_port *dig_port = enc_to_dig_port(encoder);
> +	struct intel_dp *intel_dp = &dig_port->dp;
> +	enum phy phy = intel_port_to_phy(i915, encoder->port);
> +	bool is_tc = intel_phy_is_tc(i915, phy);
> +	enum intel_hotplug_state state;
> +
> +	if (intel_dp->compliance.test_active &&
> +	    intel_dp->compliance.test_type == DP_TEST_LINK_PHY_TEST_PATTERN) {
> +		intel_dp_phy_test(encoder);
> +		/* just do the PHY test and nothing else */
> +		return INTEL_HOTPLUG_UNCHANGED;
> +	}
> +
> +	state = intel_encoder_hotplug(encoder, connector);
> +
> +	if (connector->base.connector_type == DRM_MODE_CONNECTOR_HDMIA)
> +		call_with_modeset_ctx(intel_hdmi_reset_link, encoder);
> +	else
> +		call_with_modeset_ctx(intel_dp_retrain_link, encoder);
>  
>  	/*
>  	 * Unpowered type-c dongles can take some time to boot and be
> -- 
> 2.37.2

-- 
Ville Syrjälä
Intel