net: dsa: qca8k: Force CPU port to its highest bandwidth

By default autonegotiation is enabled to configure MAC on all ports.
For the CPU port autonegotiation can not be used so we need to set
some sensible defaults manually.

This patch forces the default setting of the CPU port to 1000Mbps/full
duplex which is the chip maximum capability.

Also correct size of the bit field used to configure link speed.

Fixes: 6b93fb46480a ("net-next: dsa: add new driver for qca8xxx family")
Signed-off-by: Michal Vokáč <michal.vokac@ysoft.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/qca8k.c

@@ -490,6 +490,7 @@ qca8k_setup(struct dsa_switch *ds)
 {
 	struct qca8k_priv *priv = (struct qca8k_priv *)ds->priv;
 	int ret, i, phy_mode = -1;
+	u32 mask;
 
 	/* Make sure that port 0 is the cpu port */
 	if (!dsa_is_cpu_port(ds, 0)) {
@@ -515,7 +516,10 @@ qca8k_setup(struct dsa_switch *ds)
 	if (ret < 0)
 		return ret;
 
-	/* Enable CPU Port */
+	/* Enable CPU Port, force it to maximum bandwidth and full-duplex */
+	mask = QCA8K_PORT_STATUS_SPEED_1000 | QCA8K_PORT_STATUS_TXFLOW |
+	       QCA8K_PORT_STATUS_RXFLOW | QCA8K_PORT_STATUS_DUPLEX;
+	qca8k_write(priv, QCA8K_REG_PORT_STATUS(QCA8K_CPU_PORT), mask);
 	qca8k_reg_set(priv, QCA8K_REG_GLOBAL_FW_CTRL0,
 		      QCA8K_GLOBAL_FW_CTRL0_CPU_PORT_EN);
 	qca8k_port_set_status(priv, QCA8K_CPU_PORT, 1);

drivers/net/dsa/qca8k.h

@@ -51,8 +51,10 @@
 #define QCA8K_GOL_MAC_ADDR0				0x60
 #define QCA8K_GOL_MAC_ADDR1				0x64
 #define QCA8K_REG_PORT_STATUS(_i)			(0x07c + (_i) * 4)
-#define   QCA8K_PORT_STATUS_SPEED			GENMASK(2, 0)
-#define   QCA8K_PORT_STATUS_SPEED_S			0
+#define   QCA8K_PORT_STATUS_SPEED			GENMASK(1, 0)
+#define   QCA8K_PORT_STATUS_SPEED_10			0
+#define   QCA8K_PORT_STATUS_SPEED_100			0x1
+#define   QCA8K_PORT_STATUS_SPEED_1000			0x2
 #define   QCA8K_PORT_STATUS_TXMAC			BIT(2)
 #define   QCA8K_PORT_STATUS_RXMAC			BIT(3)
 #define   QCA8K_PORT_STATUS_TXFLOW			BIT(4)