[PATCH 04/14] drivers: net: dsa: qca8k: apply suggested packet priority

[Ansuel Smith]

The port 5 of the ar8337 have some problem in flood condition. The
original legacy driver had some specific buffer and priority settings
for the different port suggested by the QCA switch team. Add this
missing settings to improve switch stability under load condition.

Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
---
 drivers/net/dsa/qca8k.c | 42 +++++++++++++++++++++++++++++++++++++++++
 drivers/net/dsa/qca8k.h | 24 +++++++++++++++++++++++
 2 files changed, 66 insertions(+)

diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index b8bfc7acf6f4..7408cbee05c2 100644
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c
@@ -701,6 +701,7 @@ qca8k_setup(struct dsa_switch *ds)
 {
 	struct qca8k_priv *priv = (struct qca8k_priv *)ds->priv;
 	int ret, i;
+	u32 mask;
 
 	/* Make sure that port 0 is the cpu port */
 	if (!dsa_is_cpu_port(ds, 0)) {
@@ -785,6 +786,47 @@ qca8k_setup(struct dsa_switch *ds)
 		priv->port_mtu[i] = ETH_FRAME_LEN + ETH_FCS_LEN;
 	qca8k_write(priv, QCA8K_MAX_FRAME_SIZE, ETH_FRAME_LEN + ETH_FCS_LEN);
 
+	/* The port 5 of the switch ar8337 have some problem in flood condition.
+	 * To fix this the original code has some specific priority values
+	 * suggested by the QCA switch team.
+	 */
+	for (i = 0; i < QCA8K_NUM_PORTS; i++) {
+		switch (i) {
+		/* The 2 CPU port and port 5 requires some different
+		 * priority than any other ports.
+		 */
+		case 0:
+		case 5:
+		case 6:
+			mask = QCA8K_PORT_HOL_CTRL0_EG_PRI0(0x3) |
+				QCA8K_PORT_HOL_CTRL0_EG_PRI1(0x4) |
+				QCA8K_PORT_HOL_CTRL0_EG_PRI2(0x4) |
+				QCA8K_PORT_HOL_CTRL0_EG_PRI3(0x4) |
+				QCA8K_PORT_HOL_CTRL0_EG_PRI4(0x6) |
+				QCA8K_PORT_HOL_CTRL0_EG_PRI5(0x8) |
+				QCA8K_PORT_HOL_CTRL0_EG_PORT(0x1e);
+			break;
+		default:
+			mask = QCA8K_PORT_HOL_CTRL0_EG_PRI0(0x3) |
+				QCA8K_PORT_HOL_CTRL0_EG_PRI1(0x4) |
+				QCA8K_PORT_HOL_CTRL0_EG_PRI2(0x6) |
+				QCA8K_PORT_HOL_CTRL0_EG_PRI3(0x8) |
+				QCA8K_PORT_HOL_CTRL0_EG_PORT(0x19);
+		}
+		qca8k_write(priv, QCA8K_REG_PORT_HOL_CTRL0(i), mask);
+
+		mask = QCA8K_PORT_HOL_CTRL1_ING(0x6) |
+		       QCA8K_PORT_HOL_CTRL1_EG_PRI_BUF_EN |
+		       QCA8K_PORT_HOL_CTRL1_EG_PORT_BUF_EN |
+		       QCA8K_PORT_HOL_CTRL1_WRED_EN;
+		qca8k_rmw(priv, QCA8K_REG_PORT_HOL_CTRL1(i),
+			  QCA8K_PORT_HOL_CTRL1_ING_BUF |
+			  QCA8K_PORT_HOL_CTRL1_EG_PRI_BUF_EN |
+			  QCA8K_PORT_HOL_CTRL1_EG_PORT_BUF_EN |
+			  QCA8K_PORT_HOL_CTRL1_WRED_EN,
+			  mask);
+	}
+
 	/* Flush the FDB table */
 	qca8k_fdb_flush(priv);
 
diff --git a/drivers/net/dsa/qca8k.h b/drivers/net/dsa/qca8k.h
index e0b679133880..0ff7abbd40dc 100644
--- a/drivers/net/dsa/qca8k.h
+++ b/drivers/net/dsa/qca8k.h
@@ -163,6 +163,30 @@
 #define   QCA8K_PORT_LOOKUP_STATE			GENMASK(18, 16)
 #define   QCA8K_PORT_LOOKUP_LEARN			BIT(20)
 
+#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)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI1_BUF		GENMASK(7, 4)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI1(x)		((x) << 4)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI2_BUF		GENMASK(11, 8)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI2(x)		((x) << 8)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI3_BUF		GENMASK(15, 12)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI3(x)		((x) << 12)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI4_BUF		GENMASK(19, 16)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI4(x)		((x) << 16)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI5_BUF		GENMASK(23, 20)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PRI5(x)		((x) << 20)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PORT_BUF		GENMASK(29, 24)
+#define   QCA8K_PORT_HOL_CTRL0_EG_PORT(x)		((x) << 24)
+
+#define QCA8K_REG_PORT_HOL_CTRL1(_i)			(0x974 + (_i) * 0x8)
+#define   QCA8K_PORT_HOL_CTRL1_ING_BUF			GENMASK(3, 0)
+#define   QCA8K_PORT_HOL_CTRL1_ING(x)			((x) << 0)
+#define   QCA8K_PORT_HOL_CTRL1_EG_PRI_BUF_EN		BIT(6)
+#define   QCA8K_PORT_HOL_CTRL1_EG_PORT_BUF_EN		BIT(7)
+#define   QCA8K_PORT_HOL_CTRL1_WRED_EN			BIT(8)
+#define   QCA8K_PORT_HOL_CTRL1_EG_MIRROR_EN		BIT(16)
+
 /* Pkt edit registers */
 #define QCA8K_EGRESS_VLAN(x)				(0x0c70 + (4 * (x / 2)))
 
-- 
2.30.2