drm/i915: Skip some timing checks on BXT/GLK DSI transcoders

[ Upstream commit 20c2dbf ]

Apparently some BXT/GLK systems have DSI panels whose timings
don't agree with the normal cpu transcoder hblank>=32 limitation.
This is perhaps fine as there are no specific hblank/etc. limits
listed for the BXT/GLK DSI transcoders.

Move those checks out from the global intel_mode_valid() into
into connector specific .mode_valid() hooks, skipping BXT/GLK
DSI connectors. We'll leave the basic [hv]display/[hv]total
checks in intel_mode_valid() as those seem like sensible upper
limits regardless of the transcoder used.

Cc: stable@vger.kernel.org
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9720
Fixes: 8f4b106 ("drm/i915: Check some transcoder timing minimum limits")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231127145028.4899-1-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
(cherry picked from commit e0ef2da)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: vsyrjala

drivers/gpu/drm/i915/display/icl_dsi.c

@@ -1500,6 +1500,13 @@ static void gen11_dsi_post_disable(struct intel_atomic_state *state,
 static enum drm_mode_status gen11_dsi_mode_valid(struct drm_connector *connector,
 						 struct drm_display_mode *mode)
 {
+	struct drm_i915_private *i915 = to_i915(connector->dev);
+	enum drm_mode_status status;
+
+	status = intel_cpu_transcoder_mode_valid(i915, mode);
+	if (status != MODE_OK)
+		return status;
+
 	/* FIXME: DSC? */
 	return intel_dsi_mode_valid(connector, mode);
 }

drivers/gpu/drm/i915/display/intel_crt.c

@@ -343,8 +343,13 @@ intel_crt_mode_valid(struct drm_connector *connector,
 	struct drm_device *dev = connector->dev;
 	struct drm_i915_private *dev_priv = to_i915(dev);
 	int max_dotclk = dev_priv->max_dotclk_freq;
+	enum drm_mode_status status;
 	int max_clock;
 
+	status = intel_cpu_transcoder_mode_valid(dev_priv, mode);
+	if (status != MODE_OK)
+		return status;
+
 	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
 		return MODE_NO_DBLESCAN;
 

drivers/gpu/drm/i915/display/intel_display.c

@@ -8229,6 +8229,16 @@ intel_mode_valid(struct drm_device *dev,
 	    mode->vtotal > vtotal_max)
 		return MODE_V_ILLEGAL;
 
+	return MODE_OK;
+}
+
+enum drm_mode_status intel_cpu_transcoder_mode_valid(struct drm_i915_private *dev_priv,
+						     const struct drm_display_mode *mode)
+{
+	/*
+	 * Additional transcoder timing limits,
+	 * excluding BXT/GLK DSI transcoders.
+	 */
 	if (DISPLAY_VER(dev_priv) >= 5) {
 		if (mode->hdisplay < 64 ||
 		    mode->htotal - mode->hdisplay < 32)

drivers/gpu/drm/i915/display/intel_display.h

@@ -554,6 +554,9 @@ enum drm_mode_status
 intel_mode_valid_max_plane_size(struct drm_i915_private *dev_priv,
 				const struct drm_display_mode *mode,
 				bool bigjoiner);
+enum drm_mode_status
+intel_cpu_transcoder_mode_valid(struct drm_i915_private *i915,
+				const struct drm_display_mode *mode);
 enum phy intel_port_to_phy(struct drm_i915_private *i915, enum port port);
 bool is_trans_port_sync_mode(const struct intel_crtc_state *state);
 bool intel_crtc_is_bigjoiner_slave(const struct intel_crtc_state *crtc_state);

drivers/gpu/drm/i915/display/intel_dp.c

@@ -973,6 +973,10 @@ intel_dp_mode_valid(struct drm_connector *_connector,
 	enum drm_mode_status status;
 	bool dsc = false, bigjoiner = false;
 
+	status = intel_cpu_transcoder_mode_valid(dev_priv, mode);
+	if (status != MODE_OK)
+		return status;
+
 	if (mode->flags & DRM_MODE_FLAG_DBLCLK)
 		return MODE_H_ILLEGAL;
 

drivers/gpu/drm/i915/display/intel_dp_mst.c

@@ -703,6 +703,10 @@ intel_dp_mst_mode_valid_ctx(struct drm_connector *connector,
 		return 0;
 	}
 
+	*status = intel_cpu_transcoder_mode_valid(dev_priv, mode);
+	if (*status != MODE_OK)
+		return 0;
+
 	if (mode->flags & DRM_MODE_FLAG_DBLSCAN) {
 		*status = MODE_NO_DBLESCAN;
 		return 0;

drivers/gpu/drm/i915/display/intel_dvo.c

@@ -225,10 +225,16 @@ intel_dvo_mode_valid(struct drm_connector *connector,
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
 	struct intel_dvo *intel_dvo = intel_attached_dvo(intel_connector);
+	struct drm_i915_private *i915 = to_i915(intel_connector->base.dev);
 	const struct drm_display_mode *fixed_mode =
 		intel_panel_fixed_mode(intel_connector, mode);
 	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
 	int target_clock = mode->clock;
+	enum drm_mode_status status;
+
+	status = intel_cpu_transcoder_mode_valid(i915, mode);
+	if (status != MODE_OK)
+		return status;
 
 	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
 		return MODE_NO_DBLESCAN;

drivers/gpu/drm/i915/display/intel_hdmi.c

@@ -1987,6 +1987,10 @@ intel_hdmi_mode_valid(struct drm_connector *connector,
 	bool has_hdmi_sink = intel_has_hdmi_sink(hdmi, connector->state);
 	bool ycbcr_420_only;
 
+	status = intel_cpu_transcoder_mode_valid(dev_priv, mode);
+	if (status != MODE_OK)
+		return status;
+
 	if ((mode->flags & DRM_MODE_FLAG_3D_MASK) == DRM_MODE_FLAG_3D_FRAME_PACKING)
 		clock *= 2;
 

drivers/gpu/drm/i915/display/intel_lvds.c

@@ -389,11 +389,16 @@ intel_lvds_mode_valid(struct drm_connector *connector,
 		      struct drm_display_mode *mode)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
+	struct drm_i915_private *i915 = to_i915(intel_connector->base.dev);
 	const struct drm_display_mode *fixed_mode =
 		intel_panel_fixed_mode(intel_connector, mode);
 	int max_pixclk = to_i915(connector->dev)->max_dotclk_freq;
 	enum drm_mode_status status;
 
+	status = intel_cpu_transcoder_mode_valid(i915, mode);
+	if (status != MODE_OK)
+		return status;
+
 	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
 		return MODE_NO_DBLESCAN;
 

drivers/gpu/drm/i915/display/intel_sdvo.c

@@ -1873,13 +1873,19 @@ static enum drm_mode_status
 intel_sdvo_mode_valid(struct drm_connector *connector,
 		      struct drm_display_mode *mode)
 {
+	struct drm_i915_private *i915 = to_i915(connector->dev);
 	struct intel_sdvo *intel_sdvo = intel_attached_sdvo(to_intel_connector(connector));
 	struct intel_sdvo_connector *intel_sdvo_connector =
 		to_intel_sdvo_connector(connector);
-	int max_dotclk = to_i915(connector->dev)->max_dotclk_freq;
 	bool has_hdmi_sink = intel_has_hdmi_sink(intel_sdvo_connector, connector->state);
+	int max_dotclk = i915->max_dotclk_freq;
+	enum drm_mode_status status;
 	int clock = mode->clock;
 
+	status = intel_cpu_transcoder_mode_valid(i915, mode);
+	if (status != MODE_OK)
+		return status;
+
 	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
 		return MODE_NO_DBLESCAN;