net: dsa: qca8k: add GLOBAL_FC settings needed for qca8327

Switch qca8327 needs special settings for the GLOBAL_FC_THRES regs.
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/qca8k.c

@@ -930,6 +930,16 @@ qca8k_setup(struct dsa_switch *ds)
 		}
 	}
 
+	/* Special GLOBAL_FC_THRESH value are needed for ar8327 switch */
+	if (priv->switch_id == QCA8K_ID_QCA8327) {
+		mask = QCA8K_GLOBAL_FC_GOL_XON_THRES(288) |
+		       QCA8K_GLOBAL_FC_GOL_XOFF_THRES(496);
+		qca8k_rmw(priv, QCA8K_REG_GLOBAL_FC_THRESH,
+			  QCA8K_GLOBAL_FC_GOL_XON_THRES_S |
+			  QCA8K_GLOBAL_FC_GOL_XOFF_THRES_S,
+			  mask);
+	}
+
 	/* Setup our port MTUs to match power on defaults */
 	for (i = 0; i < QCA8K_NUM_PORTS; i++)
 		priv->port_mtu[i] = ETH_FRAME_LEN + ETH_FCS_LEN;

drivers/net/dsa/qca8k.h

@@ -168,6 +168,12 @@
 #define   QCA8K_PORT_LOOKUP_STATE			GENMASK(18, 16)
 #define   QCA8K_PORT_LOOKUP_LEARN			BIT(20)
 
+#define QCA8K_REG_GLOBAL_FC_THRESH			0x800
+#define   QCA8K_GLOBAL_FC_GOL_XON_THRES(x)		((x) << 16)
+#define   QCA8K_GLOBAL_FC_GOL_XON_THRES_S		GENMASK(24, 16)
+#define   QCA8K_GLOBAL_FC_GOL_XOFF_THRES(x)		((x) << 0)
+#define   QCA8K_GLOBAL_FC_GOL_XOFF_THRES_S		GENMASK(8, 0)
+
 #define QCA8K_REG_PORT_HOL_CTRL0(_i)			(0x970 + (_i) * 0x8)
 #define   QCA8K_PORT_HOL_CTRL0_EG_PRI0_BUF		GENMASK(3, 0)
 #define   QCA8K_PORT_HOL_CTRL0_EG_PRI0(x)		((x) << 0)