net: dsa: sja1105: migrate to xpcs for SGMII

There is a desire to use the generic driver for the Synopsys XPCS
located in drivers/net/pcs, and to achieve that, the sja1105 driver must
expose an MDIO bus for the SGMII PCS, because the XPCS probes as an
mdio_device.

In preparation of the SJA1110 which in fact has a different access
procedure for the SJA1105, we register this PCS MDIO bus once in the
common code, but we implement function pointers for the read and write
methods. In this patch there is a single implementation for them.

There is exactly one MDIO bus for the PCS, this will contain all PCSes
at MDIO addresses equal to the port number.

We delete a bunch of hardware support code because the xpcs driver
already does what we need.

We need to hack up the MDIO reads for the PHY ID, since our XPCS
instantiation returns zeroes and there are some specific fixups which
need to be applied by the xpcs driver.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/net/dsa/sja1105/sja1105.h b/drivers/net/dsa/sja1105/sja1105.h
index 5f3449351668..82450921059a 100644
--- a/drivers/net/dsa/sja1105/sja1105.h
+++ b/drivers/net/dsa/sja1105/sja1105.h
@@ -133,6 +133,8 @@ struct sja1105_info {
 	bool (*rxtstamp)(struct dsa_switch *ds, int port, struct sk_buff *skb);
 	void (*txtstamp)(struct dsa_switch *ds, int port, struct sk_buff *skb);
 	int (*clocking_setup)(struct sja1105_private *priv);
+	int (*pcs_mdio_read)(struct mii_bus *bus, int phy, int reg);
+	int (*pcs_mdio_write)(struct mii_bus *bus, int phy, int reg, u16 val);
 	const char *name;
 	bool supports_mii[SJA1105_MAX_NUM_PORTS];
 	bool supports_rmii[SJA1105_MAX_NUM_PORTS];
@@ -265,6 +267,8 @@ struct sja1105_private {
 	struct sja1105_cbs_entry *cbs;
 	struct mii_bus *mdio_base_t1;
 	struct mii_bus *mdio_base_tx;
+	struct mii_bus *mdio_pcs;
+	struct dw_xpcs *xpcs[SJA1105_MAX_NUM_PORTS];
 	struct sja1105_tagger_data tagger_data;
 	struct sja1105_ptp_data ptp_data;
 	struct sja1105_tas_data tas_data;
@@ -297,6 +301,8 @@ void sja1105_frame_memory_partitioning(struct sja1105_private *priv);
 /* From sja1105_mdio.c */
 int sja1105_mdiobus_register(struct dsa_switch *ds);
 void sja1105_mdiobus_unregister(struct dsa_switch *ds);
+int sja1105_pcs_mdio_read(struct mii_bus *bus, int phy, int reg);
+int sja1105_pcs_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val);
 
 /* From sja1105_devlink.c */
 int sja1105_devlink_setup(struct dsa_switch *ds);