[PATCH 6/6] drm: rcar-du: Stop accessing non-existant registers on gen4

[Tomi Valkeinen]

The following registers do not exist on gen4, so we should not write
them: DEF6Rm, DEF8Rm, ESCRn, OTARn.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas at ideasonboard.com>
---
 drivers/gpu/drm/rcar-du/rcar_du_crtc.c  | 8 +++++---
 drivers/gpu/drm/rcar-du/rcar_du_group.c | 6 ++++--
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
index 8d660a6141bf..56b23333993c 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
@@ -289,10 +289,12 @@ static void rcar_du_crtc_set_display_timing(struct rcar_du_crtc *rcrtc)
 		escr = params.escr;
 	}
 
-	dev_dbg(rcrtc->dev->dev, "%s: ESCR 0x%08x\n", __func__, escr);
+	if (rcdu->info->gen < 4) {
+		dev_dbg(rcrtc->dev->dev, "%s: ESCR 0x%08x\n", __func__, escr);
 
-	rcar_du_crtc_write(rcrtc, rcrtc->index % 2 ? ESCR13 : ESCR02, escr);
-	rcar_du_crtc_write(rcrtc, rcrtc->index % 2 ? OTAR13 : OTAR02, 0);
+		rcar_du_crtc_write(rcrtc, rcrtc->index % 2 ? ESCR13 : ESCR02, escr);
+		rcar_du_crtc_write(rcrtc, rcrtc->index % 2 ? OTAR13 : OTAR02, 0);
+	}
 
 	/* Signal polarities */
 	dsmr = ((mode->flags & DRM_MODE_FLAG_PVSYNC) ? DSMR_VSL : 0)
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_group.c b/drivers/gpu/drm/rcar-du/rcar_du_group.c
index 6da01760ede5..c236e2aa8a01 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_group.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_group.c
@@ -148,7 +148,8 @@ static void rcar_du_group_setup(struct rcar_du_group *rgrp)
 	}
 	rcar_du_group_write(rgrp, DEFR5, DEFR5_CODE | DEFR5_DEFE5);
 
-	rcar_du_group_setup_pins(rgrp);
+	if (rcdu->info->gen < 4)
+		rcar_du_group_setup_pins(rgrp);
 
 	/*
 	 * TODO: Handle routing of the DU output to CMM dynamically, as we
@@ -160,7 +161,8 @@ static void rcar_du_group_setup(struct rcar_du_group *rgrp)
 	rcar_du_group_write(rgrp, DEFR7, defr7);
 
 	if (rcdu->info->gen >= 2) {
-		rcar_du_group_setup_defr8(rgrp);
+		if (rcdu->info->gen < 4)
+			rcar_du_group_setup_defr8(rgrp);
 		rcar_du_group_setup_didsr(rgrp);
 	}
 
-- 
2.34.1