net: dsa: microchip: ksz8: Make flow control, speed, and duplex on CPU port configurable

Allow flow control, speed, and duplex settings on the CPU port to be
configurable. Previously, the speed and duplex relied on default switch
values, which limited flexibility. Additionally, flow control was
hardcoded and only functional in duplex mode. This update enhances the
configurability of these parameters.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://lore.kernel.org/r/20231127145101.3039399-2-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: microchip: Remove unused declarations

Commit 91a98917a883 ("net: dsa: microchip: move switch chip_id detection to ksz_common")
removed ksz8_switch_detect() but not its declaration.
Commit 6ec23aaaac43 ("net: dsa: microchip: move ksz_dev_ops to ksz_common.c")
declared but never implemented other functions.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20230821125501.19624-1-yuehaibing@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: microchip: Make ksz8_w_sta_mac_table() static

Since ksz8_w_sta_mac_table() is only used within ksz8795.c, make it static
to limit its scope.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: microchip: ksz8: Make ksz8_r_sta_mac_table() static

As ksz8_r_sta_mac_table() is only used within ksz8795.c, there is no need
to export it. Make the function static for better encapsulation.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: microchip: ksz8: Implement add/del_fdb and use static MAC table operations

Add support for add/del_fdb operations and utilize the refactored static
MAC table code. This resolves kernel warnings caused by the lack of fdb
add function support in the current driver.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: microchip: ksz8: add MTU configuration support

Make MTU configurable on KSZ87xx and KSZ88xx series of switches.

Before this patch, pre-configured behavior was different on different
switch series, due to opposite meaning of the same bit:
- KSZ87xx: Reg 4, Bit 1 - if 1, max frame size is 1532; if 0 - 1514
- KSZ88xx: Reg 4, Bit 1 - if 1, max frame size is 1514; if 0 - 1532

Since the code was telling "... SW_LEGAL_PACKET_DISABLE, true)", I
assume, the idea was to set max frame size to 1532.

With this patch, by setting MTU size 1500, both switch series will be
configured to the 1532 frame limit.

This patch was tested on KSZ8873.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: dsa: microchip: allow to pass return values for PHY read/write accesses

PHY access may end with errors on different levels. So, allow to forward
return values where possible.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: microchip: remove the struct ksz8

This patch removes the struct ksz8 from ksz8.h which is no longer
needed. The platform bus specific details are now deferenced through
dev->priv.

Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: microchip: move ksz8->shifts to ksz_common

This patch moves ksz8->shifts from ksz8795.c to ksz_common.c. The shifts
are dereferenced using dev->info->shifts.

Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: microchip: move ksz8->masks to ksz_common

This patch moves the ksz8->masks from ksz8795.c to ksz_common.c. The
mask will be dereferenced using dev->info->masks.

Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: microchip: move ksz8->regs to ksz_common

This patch moves the ksz8->regs from ksz8795.c to the ksz_common.c. And
the regs is dereferrenced using dev->info->regs.

Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: microchip: move ksz_dev_ops to ksz_common.c

This patch move the ksz_dev_ops from individual files to ksz_common.c.
And the dev_ops is assigned to ksz_device based on the switch detect.
This reduces the redundant function and allows to reuse the
functionality for LAN937x which has similar register set.

Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dsa: microchip: ksz8xxx: Replace kernel.h with the necessary inclusions

When kernel.h is used in the headers it adds a lot into dependency hell,
especially when there are circular dependencies are involved.

Replace kernel.h inclusion with the list of what is really being used.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/41d99ef8629e1db03d4f2662f5556611e0b94652.1654323308.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: microchip: ksz8795: handle eee specif erratum

According to erratum described in DS80000687C[1]: "Module 2: Link drops with
some EEE link partners.", we need to "Disable the EEE next page
exchange in EEE Global Register 2"

1 - https://ww1.microchip.com/downloads/en/DeviceDoc/KSZ87xx-Errata-DS80000687C.pdf

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20220316125529.1489045-1-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: dsa: microchip: ksz8795: move register offsets and shifts to separate struct

In order to get this driver used with other switches the functions need
to use different offsets and register shifts. This patch changes the
direct use of the register defines to register description structures,
which can be set depending on the chips register layout.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>