[PATCH v4 2/2] net: dsa: ocelot: Add support for QinQ Operation

[hongbo.wang@nxp.com]

From: "hongbo.wang" <hongbo.wang@nxp.com>

This featue can be test using network test tools
TX-tool -----> swp0  -----> swp1 -----> RX-tool

TX-tool simulates Customer that will send and receive packets with single
VLAN tag(CTAG), RX-tool simulates Service-Provider that will send and
receive packets with double VLAN tag(STAG and CTAG). This refers to
"4.3.3 Provider Bridges and Q-in-Q Operation" in VSC99599_1_00_TS.pdf.

The related test commands:
1.
ip link add dev br0 type bridge
ip link set dev swp1 master br0
ip link set br0 type bridge vlan_protocol 802.1ad
ip link set dev swp0 master br0

2.
ip link set dev br0 type bridge vlan_filtering 1
bridge vlan add dev swp0 vid 100 pvid
bridge vlan add dev swp1 vid 100
Result:
Customer(tpid:8100 vid:111) -> swp0 -> swp1 -> ISP(STAG \
                tpid:88A8 vid:100, CTAG tpid:8100 vid:111)

3.
bridge vlan del dev swp0 vid 1 pvid
bridge vlan add dev swp0 vid 100 pvid untagged
Result:
ISP(tpid:88A8 vid:100 tpid:8100 vid:222) -> swp1 -> swp0 ->\
		Customer(tpid:8100 vid:222)

Signed-off-by: hongbo.wang <hongbo.wang@nxp.com>
---
 drivers/net/dsa/ocelot/felix.c     | 12 +++++++
 drivers/net/ethernet/mscc/ocelot.c | 53 +++++++++++++++++++++++++-----
 include/soc/mscc/ocelot.h          |  2 ++
 3 files changed, 59 insertions(+), 8 deletions(-)

diff --git a/drivers/net/dsa/ocelot/felix.c b/drivers/net/dsa/ocelot/felix.c
index c69d9592a2b7..72a27b61080e 100644
--- a/drivers/net/dsa/ocelot/felix.c
+++ b/drivers/net/dsa/ocelot/felix.c
@@ -131,10 +131,16 @@ static void felix_vlan_add(struct dsa_switch *ds, int port,
 			   const struct switchdev_obj_port_vlan *vlan)
 {
 	struct ocelot *ocelot = ds->priv;
+	struct ocelot_port *ocelot_port = ocelot->ports[port];
 	u16 flags = vlan->flags;
 	u16 vid;
 	int err;
 
+	if (vlan->proto == ETH_P_8021AD) {
+		ocelot->enable_qinq = true;
+		ocelot_port->qinq_mode = true;
+	}
+
 	if (dsa_is_cpu_port(ds, port))
 		flags &= ~BRIDGE_VLAN_INFO_UNTAGGED;
 
@@ -154,9 +160,15 @@ static int felix_vlan_del(struct dsa_switch *ds, int port,
 			  const struct switchdev_obj_port_vlan *vlan)
 {
 	struct ocelot *ocelot = ds->priv;
+	struct ocelot_port *ocelot_port = ocelot->ports[port];
 	u16 vid;
 	int err;
 
+	if (vlan->proto == ETH_P_8021AD) {
+		ocelot->enable_qinq = false;
+		ocelot_port->qinq_mode = false;
+	}
+
 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; vid++) {
 		err = ocelot_vlan_del(ocelot, port, vid);
 		if (err) {
diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index f2d94b026d88..b5fec6855afd 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -143,6 +143,8 @@ static int ocelot_port_set_native_vlan(struct ocelot *ocelot, int port,
 				       u16 vid)
 {
 	struct ocelot_port *ocelot_port = ocelot->ports[port];
+	u32 port_tpid = 0;
+	u32 tag_tpid = 0;
 	u32 val = 0;
 
 	if (ocelot_port->vid != vid) {
@@ -156,8 +158,14 @@ static int ocelot_port_set_native_vlan(struct ocelot *ocelot, int port,
 		ocelot_port->vid = vid;
 	}
 
-	ocelot_rmw_gix(ocelot, REW_PORT_VLAN_CFG_PORT_VID(vid),
-		       REW_PORT_VLAN_CFG_PORT_VID_M,
+	if (ocelot_port->qinq_mode)
+		port_tpid = REW_PORT_VLAN_CFG_PORT_TPID(ETH_P_8021AD);
+	else
+		port_tpid = REW_PORT_VLAN_CFG_PORT_TPID(ETH_P_8021Q);
+
+	ocelot_rmw_gix(ocelot, REW_PORT_VLAN_CFG_PORT_VID(vid) | port_tpid,
+		       REW_PORT_VLAN_CFG_PORT_VID_M |
+		       REW_PORT_VLAN_CFG_PORT_TPID_M,
 		       REW_PORT_VLAN_CFG, port);
 
 	if (ocelot_port->vlan_aware && !ocelot_port->vid)
@@ -180,12 +188,28 @@ static int ocelot_port_set_native_vlan(struct ocelot *ocelot, int port,
 		else
 			/* Tag all frames */
 			val = REW_TAG_CFG_TAG_CFG(3);
+
+		if (ocelot_port->qinq_mode)
+			tag_tpid = REW_TAG_CFG_TAG_TPID_CFG(1);
+		else
+			tag_tpid = REW_TAG_CFG_TAG_TPID_CFG(0);
 	} else {
-		/* Port tagging disabled. */
-		val = REW_TAG_CFG_TAG_CFG(0);
+		if (ocelot_port->qinq_mode) {
+			if (ocelot_port->vid)
+				val = REW_TAG_CFG_TAG_CFG(1);
+			else
+				val = REW_TAG_CFG_TAG_CFG(3);
+
+			tag_tpid = REW_TAG_CFG_TAG_TPID_CFG(1);
+		} else {
+			/* Port tagging disabled. */
+			val = REW_TAG_CFG_TAG_CFG(0);
+			tag_tpid = REW_TAG_CFG_TAG_TPID_CFG(0);
+		}
 	}
-	ocelot_rmw_gix(ocelot, val,
-		       REW_TAG_CFG_TAG_CFG_M,
+
+	ocelot_rmw_gix(ocelot, val | tag_tpid,
+		       REW_TAG_CFG_TAG_CFG_M | REW_TAG_CFG_TAG_TPID_CFG_M,
 		       REW_TAG_CFG, port);
 
 	return 0;
@@ -204,6 +228,15 @@ void ocelot_port_vlan_filtering(struct ocelot *ocelot, int port,
 		      ANA_PORT_VLAN_CFG_VLAN_POP_CNT(1);
 	else
 		val = 0;
+
+	/* if switch is enabled for QinQ, the port for LAN should set
+	 * VLAN_CFG.VLAN_POP_CNT=0 && VLAN_CFG.VLAN_AWARE_ENA=0.
+	 * the port for MAN should set VLAN_CFG.VLAN_POP_CNT=1 &&
+	 * VLAN_CFG.VLAN_AWARE_ENA=1. referring to 4.3.3 in VSC9959_1_00_TS.pdf
+	 */
+	if (ocelot->enable_qinq && !ocelot_port->qinq_mode)
+		val = 0;
+
 	ocelot_rmw_gix(ocelot, val,
 		       ANA_PORT_VLAN_CFG_VLAN_AWARE_ENA |
 		       ANA_PORT_VLAN_CFG_VLAN_POP_CNT_M,
@@ -217,10 +250,14 @@ EXPORT_SYMBOL(ocelot_port_vlan_filtering);
 static void ocelot_port_set_pvid(struct ocelot *ocelot, int port, u16 pvid)
 {
 	struct ocelot_port *ocelot_port = ocelot->ports[port];
+	u32 tag_type = 0;
+
+	if (ocelot_port->qinq_mode)
+		tag_type = ANA_PORT_VLAN_CFG_VLAN_TAG_TYPE;
 
 	ocelot_rmw_gix(ocelot,
-		       ANA_PORT_VLAN_CFG_VLAN_VID(pvid),
-		       ANA_PORT_VLAN_CFG_VLAN_VID_M,
+		       ANA_PORT_VLAN_CFG_VLAN_VID(pvid) | tag_type,
+		       ANA_PORT_VLAN_CFG_VLAN_VID_M | tag_type,
 		       ANA_PORT_VLAN_CFG, port);
 
 	ocelot_port->pvid = pvid;
diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h
index da369b12005f..59020bb8fe68 100644
--- a/include/soc/mscc/ocelot.h
+++ b/include/soc/mscc/ocelot.h
@@ -556,6 +556,7 @@ struct ocelot_port {
 	struct regmap			*target;
 
 	bool				vlan_aware;
+	bool				qinq_mode;
 
 	/* Ingress default VLAN (pvid) */
 	u16				pvid;
@@ -632,6 +633,7 @@ struct ocelot {
 	/* Protects the PTP clock */
 	spinlock_t			ptp_clock_lock;
 	struct ptp_pin_desc		ptp_pins[OCELOT_PTP_PINS_NUM];
+	bool				enable_qinq;
 };
 
 struct ocelot_policer {
-- 
2.17.1