net: dsa: sja1105: Fix parameters order in sja1110_pcs_mdio_write_c45()

The definition and declaration of sja1110_pcs_mdio_write_c45() don't have
parameters in the same order.

Knowing that sja1110_pcs_mdio_write_c45() is used as a function pointer
in 'sja1105_info' structure with .pcs_mdio_write_c45, and that we have:

int (*pcs_mdio_write_c45)(struct mii_bus *bus, int phy, int mmd,
int reg, u16 val);

it is likely that the definition is the one to change.

Found with cppcheck, funcArgOrderDifferent.

Fixes: ae271547bba6 ("net: dsa: sja1105: C45 only transactions for PCS")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Michael Walle <mwalle@kernel.org>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/ff2a5af67361988b3581831f7bd1eddebfb4c48f.1712082763.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: sja1105: use xpcs_create_mdiodev()

Use the new xpcs_create_mdiodev() creator, which simplifies the
creation and destruction of the mdio device associated with xpcs.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: sja1105: allow XPCS to handle mdiodev lifetime

Put the mdiodev after xpcs_create() so that the XPCS driver can manage
the lifetime of the mdiodev its using.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Remove C45 check in C22 only MDIO bus drivers

The MDIO core should not pass a C45 request via the C22 API call any
more. So remove the tests from the drivers.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: sja1105: Separate C22 and C45 transactions for T1 MDIO bus

The T1 MDIO bus driver can perform both C22 and C45 transfers. Create
separate functions for each and register the C45 versions using the
new API calls where appropriate.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: sja1105: C45 only transactions for PCS

The sja1105 MDIO bus driver only supports C45 transfers. Update the
function names to make this clear, pass the mmd as a parameter, and
register the accessors to the _c45 ops of the bus driver structure.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: sja1105: disallow C45 transactions on the BASE-TX MDIO bus

You'd think people know that the internal 100BASE-TX PHY on the SJA1110
responds only to clause 22 MDIO transactions, but they don't :)

When a clause 45 transaction is attempted, sja1105_base_tx_mdio_read()
and sja1105_base_tx_mdio_write() don't expect "reg" to contain bit 30
set (MII_ADDR_C45) and pack this value into the SPI transaction buffer.

But the field in the SPI buffer has a width smaller than 30 bits, so we
see this confusing message from the packing() API rather than a proper
rejection of C45 transactions:

Call trace:
dump_stack+0x1c/0x38
sja1105_pack+0xbc/0xc0 [sja1105]
sja1105_xfer+0x114/0x2b0 [sja1105]
sja1105_xfer_u32+0x44/0xf4 [sja1105]
sja1105_base_tx_mdio_read+0x44/0x7c [sja1105]
mdiobus_read+0x44/0x80
get_phy_c45_ids+0x70/0x234
get_phy_device+0x68/0x15c
fwnode_mdiobus_register_phy+0x74/0x240
of_mdiobus_register+0x13c/0x380
sja1105_mdiobus_register+0x368/0x490 [sja1105]
sja1105_setup+0x94/0x119c [sja1105]
Cannot store 401d2405 inside bits 24-4 (would truncate)

Fixes: 5a8f09748ee7 ("net: dsa: sja1105: register the MDIO buses for 100base-T1 and 100base-TX")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: update NXP copyright text

NXP Legal insists that the following are not fine:

- Saying "NXP Semiconductors" instead of "NXP", since the company's
registered name is "NXP"

- Putting a "(c)" sign in the copyright string

- Putting a comma in the copyright string

The only accepted copyright string format is "Copyright <year-range> NXP".

This patch changes the copyright headers in the networking files that
were sent by me, or derived from code sent by me.

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

net: dsa: sja1105: fix use-after-free after calling of_find_compatible_node, or worse

It seems that of_find_compatible_node has a weird calling convention in
which it calls of_node_put() on the "from" node argument, instead of
leaving that up to the caller. This comes from the fact that
of_find_compatible_node with a non-NULL "from" argument it only supposed
to be used as the iterator function of for_each_compatible_node(). OF
iterator functions call of_node_get on the next OF node and of_node_put()
on the previous one.

When of_find_compatible_node calls of_node_put, it actually never
expects the refcount to drop to zero, because the call is done under the
atomic devtree_lock context, and when the refcount drops to zero it
triggers a kobject and a sysfs file deletion, which assume blocking
context.

So any driver call to of_find_compatible_node is probably buggy because
an unexpected of_node_put() takes place.

What should be done is to use the of_get_compatible_child() function.

Fixes: 5a8f09748ee7 ("net: dsa: sja1105: register the MDIO buses for 100base-T1 and 100base-TX")
Link: https://lore.kernel.org/netdev/20210814010139.kzryimmp4rizlznt@skbuf/
Suggested-by: Frank Rowand <frowand.list@gmail.com>
Suggested-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: sja1105: plug in support for 2500base-x

The MAC treats 2500base-x same as SGMII (yay for that) except that it
must be set to a different speed.

Extend all places that check for SGMII to also check for 2500base-x.

Also add the missing 2500base-x compatibility matrix entry for SJA1110D.

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

net: dsa: sja1105: register the PCS MDIO bus for SJA1110

On the SJA1110, the PCS of each SERDES-capable port is accessed through
a different memory window which is 0x100 bytes in size, denoted by
"pcs_base".

In each PCS register access window, the XPCS MMDs are accessed in an
indirect way: in pages/banks of up to 0x100 addresses each. Changing the
page/bank is done by writing to a special register at the end of the
access window.

The MDIO register map accessed indirectly through the indirect banked
method described above is similar to what SJA1105 has: upper 5 bits are
the MMD, lower 16 bits are the MDIO address within that MMD.

Since the PHY ID reported by the XPCS inside SJA1110 is also all zeroes
(like SJA1105), we need to trap those reads and return a fake PHY ID so
that the xpcs driver can apply some specific fixups for our integration.

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

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>

net: dsa: sja1105: Fix assigned yet unused return code rc

The return code variable rc is being set to return error values in two
places in sja1105_mdiobus_base_tx_register and yet it is not being
returned, the function always returns 0 instead. Fix this by replacing
the return 0 with the return code rc.

Addresses-Coverity: ("Unused value")
Fixes: 5a8f09748ee7 ("net: dsa: sja1105: register the MDIO buses for 100base-T1 and 100base-TX")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: sja1105: register the MDIO buses for 100base-T1 and 100base-TX

The SJA1110 contains two types of integrated PHYs: one 100base-TX PHY
and multiple 100base-T1 PHYs.

The access procedure for the 100base-T1 PHYs is also different than it
is for the 100base-TX one. So we register 2 MDIO buses, one for the
base-TX and the other for the base-T1. Each bus has an OF node which is
a child of the "mdio" subnode of the switch, and they are recognized by
compatible string.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>