[PATCH 3/5] drm/rockchip: vop2: Delay old_{layer|port}_sel updates in setup_layer_mixer()

[Cristian Ciocaltea <cristian.ciocaltea@collabora.com>]

The old_layer_sel and old_port_sel local variables were introduced to
hold the previous VP configuration for comparisons and wait targets,
working around the premature update of vop2->old_layer_sel and
vop2->old_port_sel earlier in the function.

Remove these superfluous locals and instead defer the assignments of
vop2->old_layer_sel and vop2->old_port_sel to just before the
corresponding shadow register writes, where the transition from old to
new logically belongs.

No functional change intended.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
---
 drivers/gpu/drm/rockchip/rockchip_vop2_reg.c | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_vop2_reg.c b/drivers/gpu/drm/rockchip/rockchip_vop2_reg.c
index 5206f01ec787..1f5e8c2acecd 100644
--- a/drivers/gpu/drm/rockchip/rockchip_vop2_reg.c
+++ b/drivers/gpu/drm/rockchip/rockchip_vop2_reg.c
@@ -2136,9 +2136,7 @@ static void rk3568_vop2_setup_layer_mixer(struct vop2_video_port *vp)
 	struct drm_plane *plane;
 	u32 layer_sel = 0;
 	u32 port_sel;
-	u32 old_layer_sel = 0;
 	u32 atv_layer_sel = 0;
-	u32 old_port_sel = 0;
 	u8 layer_id;
 	u8 old_layer_id;
 	u8 layer_sel_id;
@@ -2161,8 +2159,7 @@ static void rk3568_vop2_setup_layer_mixer(struct vop2_video_port *vp)
 	else
 		ovl_ctrl &= ~RK3568_OVL_CTRL__YUV_MODE(vp->id);
 
-	old_port_sel = vop2->old_port_sel;
-	port_sel = old_port_sel;
+	port_sel = vop2->old_port_sel;
 	port_sel &= RK3568_OVL_PORT_SEL__SEL_PORT;
 
 	if (vp0->nlayers)
@@ -2188,8 +2185,7 @@ static void rk3568_vop2_setup_layer_mixer(struct vop2_video_port *vp)
 		port_sel |= FIELD_PREP(RK3588_OVL_PORT_SET__PORT3_MUX, 7);
 
 	atv_layer_sel = vop2_readl(vop2, RK3568_OVL_LAYER_SEL);
-	old_layer_sel = vop2->old_layer_sel;
-	layer_sel = old_layer_sel;
+	layer_sel = vop2->old_layer_sel;
 
 	ofs = 0;
 	for (i = 0; i < vp->id; i++)
@@ -2273,8 +2269,6 @@ static void rk3568_vop2_setup_layer_mixer(struct vop2_video_port *vp)
 			     old_win->data->layer_sel_id[vp->id]);
 	}
 
-	vop2->old_layer_sel = layer_sel;
-	vop2->old_port_sel = port_sel;
 	/*
 	 * As the RK3568_OVL_LAYER_SEL and RK3568_OVL_PORT_SEL are shared by all Video Ports,
 	 * and the configuration take effect by one Video Port's vsync.
@@ -2290,7 +2284,7 @@ static void rk3568_vop2_setup_layer_mixer(struct vop2_video_port *vp)
 	 *    of the new VP.
 	 */
 
-	if (layer_sel != old_layer_sel && atv_layer_sel != old_layer_sel) {
+	if (layer_sel != vop2->old_layer_sel && atv_layer_sel != vop2->old_layer_sel) {
 		cfg_done = vop2_readl(vop2, RK3568_REG_CFG_DONE);
 		cfg_done &= (BIT(vop2->data->nr_vps) - 1);
 		cfg_done &= ~BIT(vp->id);
@@ -2298,20 +2292,23 @@ static void rk3568_vop2_setup_layer_mixer(struct vop2_video_port *vp)
 		 * Changes of other VPs' overlays have not taken effect
 		 */
 		if (cfg_done)
-			rk3568_vop2_wait_for_layer_cfg_done(vop2, old_layer_sel);
+			rk3568_vop2_wait_for_layer_cfg_done(vop2, vop2->old_layer_sel);
 	}
 
-	if (layer_sel != old_layer_sel || port_sel != old_port_sel)
+	if (layer_sel != vop2->old_layer_sel || port_sel != vop2->old_port_sel)
 		ovl_ctrl |= FIELD_PREP(RK3568_OVL_CTRL__LAYERSEL_REGDONE_SEL, vp->id);
 	vop2_writel(vop2, RK3568_OVL_CTRL, ovl_ctrl);
 
-	if (port_sel != old_port_sel) {
+	if (port_sel != vop2->old_port_sel) {
+		vop2->old_port_sel = port_sel;
 		vop2_writel(vop2, RK3568_OVL_PORT_SEL, port_sel);
 		vop2_cfg_done(vp);
 		rk3568_vop2_wait_for_port_mux_done(vop2);
 	}
 
+	vop2->old_layer_sel = layer_sel;
 	vop2_writel(vop2, RK3568_OVL_LAYER_SEL, layer_sel);
+
 	mutex_unlock(&vop2->ovl_lock);
 }
 

-- 
2.53.0