[RFC PATCH net-next v4 14/28] net: dsa: qca8k: add priority tweak to qca8337 switch

Ansuel Smith
2021-05-08T00:30:21Z

The port 5 of the qca8337 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.
The packet priority tweak is only needed for the qca8337 switch and
other qca8k switch are not affected.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
---
drivers/net/dsa/qca8k.c | 47 +++++++++++++++++++++++++++++++++++++++++
drivers/net/dsa/qca8k.h | 25 ++++++++++++++++++++++
2 files changed, 72 insertions(+)

diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index 9c2f09e84364..69fd526344cc 100644
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c
@@ -791,6 +791,7 @@ 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)) {
@@ -896,6 +897,51 @@ qca8k_setup(struct dsa_switch *ds)
}
}

+ /* The port 5 of the qca8337 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.
+ * This problem is limited to qca8337 and other qca8k switch are not affected.
+ */
+ if (priv->switch_id == QCA8K_ID_QCA8337) {
+ 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);
+ }
+ }
+
/* 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;
@@ -1581,6 +1627,7 @@ qca8k_sw_probe(struct mdio_device *mdiodev)
return -ENODEV;
}

+ priv->switch_id = id;
priv->ds = devm_kzalloc(&mdiodev->dev, sizeof(*priv->ds), GFP_KERNEL);
if (!priv->ds)
return -ENOMEM;
diff --git a/drivers/net/dsa/qca8k.h b/drivers/net/dsa/qca8k.h
index 87a8b10459c6..42d90836dffa 100644
--- a/drivers/net/dsa/qca8k.h
+++ b/drivers/net/dsa/qca8k.h
@@ -168,6 +168,30 @@
#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)))

@@ -220,6 +244,7 @@ struct qca8k_match_data {
};

struct qca8k_priv {
+ u8 switch_id;
struct regmap *regmap;
struct mii_bus *bus;
struct ar8xxx_port_status port_sts[QCA8K_NUM_PORTS];
--
2.30.2