drm/tilcdc: adding some more devicetree config
Adding support for max-pixelclock and max-width device tree
entries. As some devices that use the tilcdc hardware module
have restrictions on the allowed/tested values. Also update DT
bindings document to reflect new parameters.
Signed-off-by: Darren Etheridge <detheridge@ti.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
index 5b68fe59e..b5b865f 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
@@ -443,10 +443,29 @@
if (mode->vdisplay > 2048)
return MODE_VIRTUAL_Y;
+ /*
+ * some devices have a maximum allowed pixel clock
+ * configured from the DT
+ */
+ if (mode->clock > priv->max_pixelclock) {
+ DBG("Pruning mode, pixel clock too high");
+ return MODE_CLOCK_HIGH;
+ }
+
+ /*
+ * some devices further limit the max horizontal resolution
+ * configured from the DT
+ */
+ if (mode->hdisplay > priv->max_width)
+ return MODE_BAD_WIDTH;
+
/* filter out modes that would require too much memory bandwidth: */
- bandwidth = mode->hdisplay * mode->vdisplay * drm_mode_vrefresh(mode);
- if (bandwidth > priv->max_bandwidth)
+ bandwidth = mode->hdisplay * mode->vdisplay *
+ drm_mode_vrefresh(mode);
+ if (bandwidth > priv->max_bandwidth) {
+ DBG("Pruning mode, exceeds defined bandwidth limit");
return MODE_BAD;
+ }
return MODE_OK;
}