Re: [PATCH v2] drm/i915: Unbreak check_digital_port_conflicts()

[Jani Nikula <jani.nikula@linux.intel.com>]

On Thu, 10 Dec 2015, ville.syrjala@linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Atomic changes broke check_digital_port_conflicts(). It needs to look
> at the global situation instead of just trying to find a conflict
> within the current atomic state.
>
> This bug made my HSW explode spectacularly after I had split the DDI
> encoders into separate DP and HDMI encoders. With the fix, things
> seem much more solid.
>
> I hope holding the connection_mutex is enough protection that we can
> actually walk the connectors even if they're not part of the current
> atomic state...
>
> v2: Regenerate the patch so that it actually applies (Jani)
>
> Cc: stable@vger.kernel.org
> Cc: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
> Fixes: 5448a00d3f06 ("drm/i915: Don't use staged config in check_digital_port_conflicts()")
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Pushed to drm-intel-next-queued, thanks for the patch and review.

BR,
Jani.

> ---
>  drivers/gpu/drm/i915/intel_display.c | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 930661de11ff..10974424bdfa 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -12260,18 +12260,22 @@ static void intel_dump_pipe_config(struct intel_crtc *crtc,
>  static bool check_digital_port_conflicts(struct drm_atomic_state *state)
>  {
>  	struct drm_device *dev = state->dev;
> -	struct intel_encoder *encoder;
>  	struct drm_connector *connector;
> -	struct drm_connector_state *connector_state;
>  	unsigned int used_ports = 0;
> -	int i;
>  
>  	/*
>  	 * Walk the connector list instead of the encoder
>  	 * list to detect the problem on ddi platforms
>  	 * where there's just one encoder per digital port.
>  	 */
> -	for_each_connector_in_state(state, connector, connector_state, i) {
> +	drm_for_each_connector(connector, dev) {
> +		struct drm_connector_state *connector_state;
> +		struct intel_encoder *encoder;
> +
> +		connector_state = drm_atomic_get_existing_connector_state(state, connector);
> +		if (!connector_state)
> +			connector_state = connector->state;
> +
>  		if (!connector_state->best_encoder)
>  			continue;

-- 
Jani Nikula, Intel Open Source Technology Center