1 files changed, 173 insertions, 0 deletions
diff --git a/target/linux/generic/backport-5.15/769-v5.19-03-net-dsa-qca8k-rework-and-simplify-mdiobus-logic.patch b/target/linux/generic/backport-5.15/769-v5.19-03-net-dsa-qca8k-rework-and-simplify-mdiobus-logic.patch
new file mode 100644
index 0000000000..12c3221077
--- /dev/null
+++ b/target/linux/generic/backport-5.15/769-v5.19-03-net-dsa-qca8k-rework-and-simplify-mdiobus-logic.patch
@@ -0,0 +1,173 @@
+From 8255212e4130bd2dc1463286a3dddb74797bbdc1 Mon Sep 17 00:00:00 2001
+From: Ansuel Smith <ansuelsmth@gmail.com>
+Date: Sat, 16 Apr 2022 01:30:14 +0200
+Subject: [PATCH 3/6] net: dsa: qca8k: rework and simplify mdiobus logic
+
+In an attempt to reduce qca8k_priv space, rework and simplify mdiobus
+logic.
+We now declare a mdiobus instead of relying on DSA phy_read/write even
+if a mdio node is not present. This is all to make the qca8k ops static
+and not switch specific. With a legacy implementation where port doesn't
+have a phy map declared in the dts with a mdio node, we declare a
+'qca8k-legacy' mdiobus. The conversion logic is used as legacy read and
+write ops are used instead of the internal one.
+Also drop the legacy_phy_port_mapping as we now declare mdiobus with ops
+that already address the workaround.
+
+Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/dsa/qca8k.c | 95 +++++++++++++----------------------------
+ drivers/net/dsa/qca8k.h |  1 -
+ 2 files changed, 29 insertions(+), 67 deletions(-)
+
+--- a/drivers/net/dsa/qca8k.c
++++ b/drivers/net/dsa/qca8k.c
+@@ -1291,83 +1291,63 @@ qca8k_internal_mdio_read(struct mii_bus
+ }
+ 
+ static int
+-qca8k_phy_write(struct dsa_switch *ds, int port, int regnum, u16 data)
++qca8k_legacy_mdio_write(struct mii_bus *slave_bus, int port, int regnum, u16 data)
+ {
+-	struct qca8k_priv *priv = ds->priv;
+-	int ret;
++	port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
+ 
+-	/* Check if the legacy mapping should be used and the
+-	 * port is not correctly mapped to the right PHY in the
+-	 * devicetree
+-	 */
+-	if (priv->legacy_phy_port_mapping)
+-		port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
+-
+-	/* Use mdio Ethernet when available, fallback to legacy one on error */
+-	ret = qca8k_phy_eth_command(priv, false, port, regnum, 0);
+-	if (!ret)
+-		return ret;
+-
+-	return qca8k_mdio_write(priv, port, regnum, data);
++	return qca8k_internal_mdio_write(slave_bus, port, regnum, data);
+ }
+ 
+ static int
+-qca8k_phy_read(struct dsa_switch *ds, int port, int regnum)
++qca8k_legacy_mdio_read(struct mii_bus *slave_bus, int port, int regnum)
+ {
+-	struct qca8k_priv *priv = ds->priv;
+-	int ret;
+-
+-	/* Check if the legacy mapping should be used and the
+-	 * port is not correctly mapped to the right PHY in the
+-	 * devicetree
+-	 */
+-	if (priv->legacy_phy_port_mapping)
+-		port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
+-
+-	/* Use mdio Ethernet when available, fallback to legacy one on error */
+-	ret = qca8k_phy_eth_command(priv, true, port, regnum, 0);
+-	if (ret >= 0)
+-		return ret;
+-
+-	ret = qca8k_mdio_read(priv, port, regnum);
+-
+-	if (ret < 0)
+-		return 0xffff;
++	port = qca8k_port_to_phy(port) % PHY_MAX_ADDR;
+ 
+-	return ret;
++	return qca8k_internal_mdio_read(slave_bus, port, regnum);
+ }
+ 
+ static int
+-qca8k_mdio_register(struct qca8k_priv *priv, struct device_node *mdio)
++qca8k_mdio_register(struct qca8k_priv *priv)
+ {
+ 	struct dsa_switch *ds = priv->ds;
++	struct device_node *mdio;
+ 	struct mii_bus *bus;
+ 
+ 	bus = devm_mdiobus_alloc(ds->dev);
+-
+ 	if (!bus)
+ 		return -ENOMEM;
+ 
+ 	bus->priv = (void *)priv;
+-	bus->name = "qca8k slave mii";
+-	bus->read = qca8k_internal_mdio_read;
+-	bus->write = qca8k_internal_mdio_write;
+-	snprintf(bus->id, MII_BUS_ID_SIZE, "qca8k-%d",
+-		 ds->index);
+-
+ 	bus->parent = ds->dev;
+ 	bus->phy_mask = ~ds->phys_mii_mask;
+-
+ 	ds->slave_mii_bus = bus;
+ 
+-	return devm_of_mdiobus_register(priv->dev, bus, mdio);
++	/* Check if the devicetree declare the port:phy mapping */
++	mdio = of_get_child_by_name(priv->dev->of_node, "mdio");
++	if (of_device_is_available(mdio)) {
++		snprintf(bus->id, MII_BUS_ID_SIZE, "qca8k-%d", ds->index);
++		bus->name = "qca8k slave mii";
++		bus->read = qca8k_internal_mdio_read;
++		bus->write = qca8k_internal_mdio_write;
++		return devm_of_mdiobus_register(priv->dev, bus, mdio);
++	}
++
++	/* If a mapping can't be found the legacy mapping is used,
++	 * using the qca8k_port_to_phy function
++	 */
++	snprintf(bus->id, MII_BUS_ID_SIZE, "qca8k-%d.%d",
++		 ds->dst->index, ds->index);
++	bus->name = "qca8k-legacy slave mii";
++	bus->read = qca8k_legacy_mdio_read;
++	bus->write = qca8k_legacy_mdio_write;
++	return devm_mdiobus_register(priv->dev, bus);
+ }
+ 
+ static int
+ qca8k_setup_mdio_bus(struct qca8k_priv *priv)
+ {
+ 	u32 internal_mdio_mask = 0, external_mdio_mask = 0, reg;
+-	struct device_node *ports, *port, *mdio;
++	struct device_node *ports, *port;
+ 	phy_interface_t mode;
+ 	int err;
+ 
+@@ -1429,24 +1409,7 @@ qca8k_setup_mdio_bus(struct qca8k_priv *
+ 					 QCA8K_MDIO_MASTER_EN);
+ 	}
+ 
+-	/* Check if the devicetree declare the port:phy mapping */
+-	mdio = of_get_child_by_name(priv->dev->of_node, "mdio");
+-	if (of_device_is_available(mdio)) {
+-		err = qca8k_mdio_register(priv, mdio);
+-		if (err)
+-			of_node_put(mdio);
+-
+-		return err;
+-	}
+-
+-	/* If a mapping can't be found the legacy mapping is used,
+-	 * using the qca8k_port_to_phy function
+-	 */
+-	priv->legacy_phy_port_mapping = true;
+-	priv->ops.phy_read = qca8k_phy_read;
+-	priv->ops.phy_write = qca8k_phy_write;
+-
+-	return 0;
++	return qca8k_mdio_register(priv);
+ }
+ 
+ static int
+--- a/drivers/net/dsa/qca8k.h
++++ b/drivers/net/dsa/qca8k.h
+@@ -382,7 +382,6 @@ struct qca8k_priv {
+ 	 * Bit 1: port enabled. Bit 0: port disabled.
+ 	 */
+ 	u8 port_enabled_map;
+-	bool legacy_phy_port_mapping;
+ 	struct qca8k_ports_config ports_config;
+ 	struct regmap *regmap;
+ 	struct mii_bus *bus;