[Intel-gfx] [PATCH 1/2] drm/i915: consolidate and tighten encoder cloning checks

[Daniel Vetter]

Only lvds/tv did actually check for cloning or not, but many more
places should.

Notices because my ivb tried to enable both cpu edp and vga on the
first crtc - the resulting confusion between has_pch_encoder,
has_dp_encoder but not actually being a pch dp encoder resulting in
hilarity (hitting a BUG).

We _really_ need an igt to random-walk our modeset space more
exhaustively.

I haven't figured out yet why exactly we see this configuration
request from the setcrtc ioctl, but I can reliably reproduce it by
unplugging a bunch of connectors and restarting X.

Strangely restarting X again fixes things ...

Cc: Chris Wilson <chris at chris-wilson.co.uk>
Cc: stable at vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 drivers/gpu/drm/i915/intel_display.c | 41 +++++++++++++++++++++---------------
 drivers/gpu/drm/i915/intel_drv.h     |  1 -
 drivers/gpu/drm/i915/intel_lvds.c    |  3 ---
 drivers/gpu/drm/i915/intel_tv.c      |  3 ---
 4 files changed, 24 insertions(+), 24 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 30ffe7f..e9aa2a5 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -5859,29 +5859,12 @@ static int haswell_crtc_mode_set(struct drm_crtc *crtc,
 	struct drm_display_mode *mode = &intel_crtc->config.requested_mode;
 	int pipe = intel_crtc->pipe;
 	int plane = intel_crtc->plane;
-	int num_connectors = 0;
-	bool is_cpu_edp = false;
-	struct intel_encoder *encoder;
 	int ret;
 
-	for_each_encoder_on_crtc(dev, crtc, encoder) {
-		switch (encoder->type) {
-		case INTEL_OUTPUT_EDP:
-			if (enc_to_dig_port(&encoder->base)->port == PORT_A)
-				is_cpu_edp = true;
-			break;
-		}
-
-		num_connectors++;
-	}
-
 	/* We are not sure yet this won't happen. */
 	WARN(!HAS_PCH_LPT(dev), "Unexpected PCH type %d\n",
 	     INTEL_PCH_TYPE(dev));
 
-	WARN(num_connectors != 1, "%d connectors attached to pipe %c\n",
-	     num_connectors, pipe_name(pipe));
-
 	WARN_ON(I915_READ(PIPECONF(intel_crtc->config.cpu_transcoder)) &
 		(PIPECONF_ENABLE | I965_PIPECONF_ACTIVE));
 
@@ -7708,6 +7691,25 @@ pipe_config_set_bpp(struct drm_crtc *crtc,
 	return bpp;
 }
 
+static bool check_encoder_cloning(struct drm_crtc *crtc)
+{
+	int num_encoders = 0;
+	bool uncloneable_encoders = false;
+	struct intel_encoder *encoder;
+
+	list_for_each_entry(encoder, &crtc->dev->mode_config.encoder_list,
+			    base.head) {
+		if (&encoder->new_crtc->base != crtc)
+			continue;
+
+		num_encoders++;
+		if (!encoder->cloneable)
+			uncloneable_encoders = true;
+	}
+
+	return !(num_encoders > 1 && uncloneable_encoders);
+}
+
 static struct intel_crtc_config *
 intel_modeset_pipe_config(struct drm_crtc *crtc,
 			  struct drm_framebuffer *fb,
@@ -7720,6 +7722,11 @@ intel_modeset_pipe_config(struct drm_crtc *crtc,
 	int plane_bpp, ret = -EINVAL;
 	bool retry = true;
 
+	if (!check_encoder_cloning(crtc)) {
+		DRM_DEBUG_KMS("rejecting invalid cloning configuration\n");
+		return ERR_PTR(-EINVAL);
+	}
+
 	pipe_config = kzalloc(sizeof(*pipe_config), GFP_KERNEL);
 	if (!pipe_config)
 		return ERR_PTR(-ENOMEM);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 3db4b14..a844a05 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -627,7 +627,6 @@ extern void intel_crtc_load_lut(struct drm_crtc *crtc);
 extern void intel_crtc_update_dpms(struct drm_crtc *crtc);
 extern void intel_encoder_destroy(struct drm_encoder *encoder);
 extern void intel_encoder_dpms(struct intel_encoder *encoder, int mode);
-extern bool intel_encoder_check_is_cloned(struct intel_encoder *encoder);
 extern void intel_connector_dpms(struct drm_connector *, int mode);
 extern bool intel_connector_get_hw_state(struct intel_connector *connector);
 extern void intel_modeset_check_state(struct drm_device *dev);
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 6554860..10c3d56 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -264,9 +264,6 @@ static bool intel_lvds_compute_config(struct intel_encoder *intel_encoder,
 		return false;
 	}
 
-	if (intel_encoder_check_is_cloned(&lvds_encoder->base))
-		return false;
-
 	if ((I915_READ(lvds_encoder->reg) & LVDS_A3_POWER_MASK) ==
 	    LVDS_A3_POWER_UP)
 		lvds_bpp = 8*3;
diff --git a/drivers/gpu/drm/i915/intel_tv.c b/drivers/gpu/drm/i915/intel_tv.c
index 7d11a5a..39debd8 100644
--- a/drivers/gpu/drm/i915/intel_tv.c
+++ b/drivers/gpu/drm/i915/intel_tv.c
@@ -914,9 +914,6 @@ intel_tv_compute_config(struct intel_encoder *encoder,
 	if (!tv_mode)
 		return false;
 
-	if (intel_encoder_check_is_cloned(&intel_tv->base))
-		return false;
-
 	pipe_config->adjusted_mode.clock = tv_mode->clock;
 	DRM_DEBUG_KMS("forcing bpc to 8 for TV\n");
 	pipe_config->pipe_bpp = 8*3;
-- 
1.7.11.7