diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index 3fb084f802e298948d2115995dec660d1b1d22b0..9bfb5b967d385d898698d87ce71347eff2ec6280 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -17,6 +17,7 @@
 #include <drm/drm_encoder.h>
 #include <drm/drm_modes.h>
 #include <drm/drm_of.h>
+#include <drm/drm_panel.h>
 
 #include <uapi/drm/drm_mode.h>
 
@@ -474,6 +475,33 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
 	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
 		val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
 
+	/*
+	 * On A20 and similar SoCs, the only way to achieve Positive Edge
+	 * (Rising Edge), is setting dclk clock phase to 2/3(240°).
+	 * By default TCON works in Negative Edge(Falling Edge),
+	 * this is why phase is set to 0 in that case.
+	 * Unfortunately there's no way to logically invert dclk through
+	 * IO_POL register.
+	 * The only acceptable way to work, triple checked with scope,
+	 * is using clock phase set to 0° for Negative Edge and set to 240°
+	 * for Positive Edge.
+	 * On A33 and similar SoCs there would be a 90° phase option,
+	 * but it divides also dclk by 2.
+	 * Following code is a way to avoid quirks all around TCON
+	 * and DOTCLOCK drivers.
+	 */
+	if (!IS_ERR(tcon->panel)) {
+		struct drm_panel *panel = tcon->panel;
+		struct drm_connector *connector = panel->connector;
+		struct drm_display_info display_info = connector->display_info;
+
+		if (display_info.bus_flags & DRM_BUS_FLAG_PIXDATA_POSEDGE)
+			clk_set_phase(tcon->dclk, 240);
+
+		if (display_info.bus_flags & DRM_BUS_FLAG_PIXDATA_NEGEDGE)
+			clk_set_phase(tcon->dclk, 0);
+	}
+
 	regmap_update_bits(tcon->regs, SUN4I_TCON0_IO_POL_REG,
 			   SUN4I_TCON0_IO_POL_HSYNC_POSITIVE | SUN4I_TCON0_IO_POL_VSYNC_POSITIVE,
 			   val);