From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
The panel fitter lives inside the pipe and so would affect all cloned
outputs. However the relevant properties (scaling mode, TV margins)
are per-connector so we could end up with a situation where each cloned
output wants a different pfit configuration. Let's just reject pfit
usage with cloning entirely.
Currently not an issue as we don't yet expose the TV margin
properties, but if/when we add those to HDMI we could end up
in this situation. For eDP/DP we don't support cloning anyyway.
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_panel.c | 27 ++++++++++++++++++++++
1 file changed, 27 insertions(+)
diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c
index dc843892b01b..593e41907d53 100644
--- a/drivers/gpu/drm/i915/display/intel_panel.c
+++ b/drivers/gpu/drm/i915/display/intel_panel.c
@@ -474,6 +474,29 @@ static int intel_pch_pfit_check_timings(const struct intel_crtc_state *crtc_stat
return 0;
}
+static int intel_pch_pfit_check_cloning(const struct intel_crtc_state *crtc_state)
+{
+ struct intel_display *display = to_intel_display(crtc_state);
+ struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+
+ /*
+ * The panel fitter is in the pipe and thus would affect every
+ * cloned output. The relevant properties (scaling mode, TV
+ * margins) are per-connector so we'd have to make sure each
+ * output sets them up identically. Seems like a very niche use
+ * case so let's just reject cloning entirely when pfit is used.
+ */
+ if (crtc_state->uapi.encoder_mask &&
+ !is_power_of_2(crtc_state->uapi.encoder_mask)) {
+ drm_dbg_kms(display->drm,
+ "[CRTC:%d:%s] no pfit when cloning\n",
+ crtc->base.base.id, crtc->base.name);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
/* adjusted_mode has been preset to be the panel's fixed mode */
static int pch_panel_fitting(struct intel_crtc_state *crtc_state,
const struct drm_connector_state *conn_state)
@@ -564,6 +587,10 @@ static int pch_panel_fitting(struct intel_crtc_state *crtc_state,
if (ret)
return ret;
+ ret = intel_pch_pfit_check_cloning(crtc_state);
+ if (ret)
+ return ret;
+
return 0;
}
--
2.45.2
