Revert "Introduce PHY listing and link_topology tracking"

This reverts commit 32bb4515e34469975abc936deb0a116c4a445817.
This reverts commit d078d480639a4f3b5fc2d56247afa38e0956483a.
This reverts commit fcc4b105caa4b844bf043375bf799c20a9c99db1.
This reverts commit 345237dbc1bdbb274c9fb9ec38976261ff4a40b8.
This reverts commit 7db69ec9cfb8b4ab50420262631fb2d1908b25bf.
This reverts commit 95132a018f00f5dad38bdcfd4180d1af955d46f6.
This reverts commit 63d5eaf35ac36cad00cfb3809d794ef0078c822b.
This reverts commit c29451aefcb42359905d18678de38e52eccb3bb5.
This reverts commit 2ab0edb505faa9ac90dee1732571390f074e8113.
This reverts commit dedd702a35793ab462fce4c737eeba0badf9718e.
This reverts commit 034fcc210349b873ece7356905be5c6ca11eef2a.
This reverts commit 9c5625f559ad6fe9f6f733c11475bf470e637d34.
This reverts commit 02018c544ef113e980a2349eba89003d6f399d22.

Looks like we need more time for reviews, and incremental
changes will be hard to make sense of. So revert.

Link: https://lore.kernel.org/all/ZZP6FV5sXEf+xd58@shell.armlinux.org.uk/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: sfp: Add helper to return the SFP bus name

Knowing the bus name is helpful when we want to expose the link topology
to userspace, add a helper to return the SFP bus name.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: pass the phy_device when disconnecting an sfp module's PHY

Pass the phy_device as a parameter to the sfp upstream .disconnect_phy
operation. This is preparatory work to help track phy devices across
a net_device's link.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: add support for rate selection

Add support for parsing the rate select thresholds and switching of the
RS0 and RS1 signals to the transceiver. This is complicated by various
revisions of SFF-8472 and interaction of SFF-8431, SFF-8079 and
INF-8074.

Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: sfp: add support for setting signalling rate

Add support to the SFP layer to allow phylink to set the signalling
rate for a SFP module. The rate given will be in units of kilo-baud
(1000 baud).

Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: sfp: make sfp_bus_find_fwnode() take a const fwnode

sfp_bus_find_fwnode() does not write to the fwnode, so let's make it
const.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: move field definitions along side register index

Just as we do for the A2h enum, arrange the A0h enum to have the
field definitions next to their corresponding register index.

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

net: sfp: convert register indexes from hex to decimal

The register indexes in the standards are in decimal rather than hex,
so lets specify them in decimal in the header file so we can easily
cross-reference without converting between hex and decimal.

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

net: sfp: provide a definition for the power level select bit

Provide a named definition for the power level select bit in the
extended status register, rather than using BIT(0) in the code.

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

net: sfp: augment SFP parsing with phy_interface_t bitmap

We currently parse the SFP EEPROM to a bitmap of ethtool link modes,
and then attempt to convert the link modes to a PHY interface mode.
While this works at present, there are cases where this is sub-optimal.
For example, where a module can operate with several different PHY
interface modes.

To start addressing this, arrange for the SFP EEPROM parsing to also
provide a bitmap of the possible PHY interface modes.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

phy: sfp: add netlink SFP support to generic SFP code

The new netlink API for reading SFP data requires a new op to be
implemented. The idea of the new netlink SFP code is that userspace is
responsible to parsing the EEPROM data and requesting pages, rather
than have the kernel decide what pages are interesting and returning
them. This allows greater flexibility for newer formats.

Currently the generic SFP code only supports simple SFPs. Allow i2c
address 0x50 and 0x51 to be accessed with page and bank must always be
0. This interface will later be extended when for example QSFP support
is added.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Vladyslav Tarasiuk <vladyslavt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: phylink: delay MAC configuration for copper SFP modules

Knowing whether we need to delay the MAC configuration because a module
may have a PHY is useful to phylink to allow NBASE-T modules to work on
systems supporting no more than 2.5G speeds.

This commit allows us to delay such configuration until after the PHY
has been probed by recording the parsed capabilities, and if the module
may have a PHY, doing no more until the module_start() notification is
called. At that point, we either have a PHY, or we don't.

We move the PHY-based setup a little later, and use the PHYs support
capabilities rather than the EEPROM parsed capabilities to determine
whether we can support the PHY.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: add module start/stop upstream notifications

When dealing with some copper modules, we can't positively know the
module capabilities are until we have probed the PHY. Without the full
capabilities, we may end up failing a module that we could otherwise
drive with a restricted set of capabilities.

An example of this would be a module with a NBASE-T PHY plugged into
a host that supports phy interface modes 2500BASE-X and SGMII. The
PHY supports 10GBASE-R, 5000BASE-X, 2500BASE-X, SGMII interface modes,
which means a subset of the capabilities are compatible with the host.

However, reading the module EEPROM leads us to believe that the module
only supports ethtool link mode 10GBASE-T, which is incompatible with
the host - and thus results in the module being rejected.

This patch adds an extra notification which are triggered after the
SFP module's PHY probe, and a corresponding notification just before
the PHY is removed.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: add more extended compliance codes

SFF-8024 is used to define various constants re-used in several SFF
SFP-related specifications. Split these constants from the enum, and
rename them to indicate that they're defined by SFF-8024.

Add and use updated SFF-8024 extended compliance code definitions for
10GBASE-T, 5GBASE-T and 2.5GBASE-T modules.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: derive interface mode from ethtool link modes

We don't need the EEPROM ID to derive the phy interface mode as we can
derive it merely from the ethtool link modes. Remove the EEPROM ID
argument to sfp_select_interface().

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: soft status and control support

Add support for the soft status and control register, which allows
TX_FAULT and RX_LOS to be monitored and TX_DISABLE to be set. We
make use of this when the board does not support GPIOs for these
signals.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: fix sfp_bus_add_upstream() warning

When building with SFP disabled, the stub for sfp_bus_add_upstream()
missed "inline". Add it.

Fixes: 727b3668b730 ("net: sfp: rework upstream interface")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: rework upstream interface

The current upstream interface is an all-or-nothing, which is
sub-optimal for future changes, as it doesn't allow the upstream driver
to prepare for the SFP module becoming available, as it is at boot.

Switch to a find-sfp-bus, add-upstream, del-upstream, put-sfp-bus
interface structure instead, which allows the upstream driver to
prepare for a module being available as soon as add-upstream is called.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: move fwnode parsing into sfp-bus layer

Rather than parsing the sfp firmware node in phylink, parse it in the
sfp-bus code, so we can re-use this code for PHYs without having to
duplicate the parsing.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: remove sfp-bus use of netdevs

The sfp-bus code now no longer has any use for the network device
structure, so remove its use.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sfp: add mandatory attach/detach methods for sfp buses

Add attach and detach methods for SFP buses, which will allow us to get
rid of the netdev storage in sfp-bus.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: phy: sfp: correct location of SFP standards

SFP standards are now available from the SNIA (Storage Networking
Industry Association) website.

Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: phy: sfp: Add HWMON support for module sensors

SFP modules can contain a number of sensors. The EEPROM also contains
recommended alarm and critical values for each sensor, and indications
of if these have been exceeded. Export this information via
HWMON. Currently temperature, VCC, bias current, transmit power, and
possibly receiver power is supported.

The sensors in the modules can either return calibrate or uncalibrated
values. Uncalibrated values need to be manipulated, using coefficients
provided in the SFP EEPROM. Uncalibrated receive power values require
floating point maths in order to calibrate them. Performing this in
the kernel is hard. So if the SFP module indicates it uses
uncalibrated values, RX power is not made available.

With this hwmon device, it is possible to view the sensor values using
lm-sensors programs:

in0: +3.29 V (crit min = +2.90 V, min = +3.00 V)
(max = +3.60 V, crit max = +3.70 V)
temp1: +33.0°C (low = -5.0°C, high = +80.0°C)
(crit low = -10.0°C, crit = +85.0°C)
power1: 1000.00 nW (max = 794.00 uW, min = 50.00 uW) ALARM (LCRIT)
(lcrit = 40.00 uW, crit = 1000.00 uW)
curr1: +0.00 A (crit min = +0.00 A, min = +0.00 A) ALARM (LCRIT, MIN)
(max = +0.01 A, crit max = +0.01 A)

The scaling sensors performs on the bias current is not particularly
good. The raw values are more useful:

curr1:
curr1_input: 0.000
curr1_min: 0.002
curr1_max: 0.010
curr1_lcrit: 0.000
curr1_crit: 0.011
curr1_min_alarm: 1.000
curr1_max_alarm: 0.000
curr1_lcrit_alarm: 1.000
curr1_crit_alarm: 0.000

In order to keep the I2C overhead to a minimum, the constant values,
such as limits and calibration coefficients are read once at module
insertion time. Thus only reading *_input and *_alarm properties
requires i2c read operations.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

phylink,sfp: negotiate interface format with MAC

Negotiate the interface format with the MAC rather than requiring it to
be a fixed type specified solely by the SFP module. This allows modules
that can work with several different interface signalling formats to
select a format compatible with the MAC - for example, a Fiber module
supporing Gigabit ethernet and faster connected to a Gigabit only MAC
needs to select the 1000BASE-X mode.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfp: improve support for direct-attach copper cables

Improve the support for direct-attach copper so that we avoid kernel
warning messages, and report the appropriate PORT_DA type to userspace.
Direct Attach cables can use a number of protocols depending on their
range of speeds.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfp: add sff module support

Add support for SFF modules, which are soldered down SFP modules.
These have a different phys_id value, and also have the present and
rate select signals omitted compared with their socketed counter-parts.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfp: convert to fwnode

Convert sfp-bus to use fwnode rather than device_node internally, so
we can support more than just device tree firmware.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfp: add documentation for kernel APIs

Add kernel-doc documentation for sfp kernel APIs, and link it into the
networking kapi documentation under "Network device support".

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sfp: add sfp-bus to bridge between network devices and sfp cages

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>