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>

mlxbf_gige: add MDIO support for BlueField-3

This patch adds initial MDIO support for the BlueField-3
SoC. Separate header files for the BlueField-2 and the
BlueField-3 SoCs have been created. These header files
hold the SoC-specific MDIO macros since the register
offsets and bit fields have changed. Also, in BlueField-3
there is a separate register for writing and reading the
MDIO data. Finally, instead of having "if" statements
everywhere to differentiate between SoC-specific logic,
a mlxbf_gige_mdio_gw_t struct was created for this purpose.

Signed-off-by: David Thompson <davthompson@nvidia.com>
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/mlxbf_gige: Fix an IS_ERR() vs NULL bug in mlxbf_gige_mdio_probe

The devm_ioremap() function returns NULL on error, it doesn't return
error pointers.

Fixes: 3a1a274e933f ("mlxbf_gige: compute MDIO period based on i1clk")
Signed-off-by: Peng Wu <wupeng58@huawei.com>
Link: https://lore.kernel.org/r/20220923023640.116057-1-wupeng58@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxbf_gige: clear MDIO gateway lock after read

The MDIO gateway (GW) lock in BlueField-2 GIGE logic is
set after read. This patch adds logic to make sure the
lock is always cleared at the end of each MDIO transaction.

Fixes: f92e1869d74e ("Add Mellanox BlueField Gigabit Ethernet driver")
Reviewed-by: Asmaa Mnebhi <asmaa@nvidia.com>
Signed-off-by: David Thompson <davthompson@nvidia.com>
Link: https://lore.kernel.org/r/20220902164247.19862-1-davthompson@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxbf_gige: compute MDIO period based on i1clk

This patch adds logic to compute the MDIO period based on
the i1clk, and thereafter write the MDIO period into the YU
MDIO config register. The i1clk resource from the ACPI table
is used to provide addressing to YU bootrecord PLL registers.
The values in these registers are used to compute MDIO period.
If the i1clk resource is not present in the ACPI table, then
the current default hardcorded value of 430Mhz is used.
The i1clk clock value of 430MHz is only accurate for boards
with BF2 mid bin and main bin SoCs. The BF2 high bin SoCs
have i1clk = 500MHz, but can support a slower MDIO period.

Fixes: f92e1869d74e ("Add Mellanox BlueField Gigabit Ethernet driver")
Reviewed-by: Asmaa Mnebhi <asmaa@nvidia.com>
Signed-off-by: David Thompson <davthompson@nvidia.com>
Link: https://lore.kernel.org/r/20220826155916.12491-1-davthompson@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

mlxbf_gige: increase MDIO polling rate to 5us

This patch increases the polling rate used by the
mlxbf_gige driver on the MDIO bus. The previous
polling rate was every 100us, and the new rate is
every 5us. With this change the amount of time
spent waiting for the MDIO BUSY signal to de-assert
drops from ~100us to ~27us for each operation.

Signed-off-by: David Thompson <davthompson@nvidia.com>
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Link: https://lore.kernel.org/r/20220505162309.20050-1-davthompson@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/mlxbf_gige: Make use of devm_platform_ioremap_resourcexxx()

Use the devm_platform_ioremap_resource_byname() helper instead of
calling platform_get_resource_byname() and devm_ioremap_resource()
separately

Use the devm_platform_ioremap_resource() helper instead of
calling platform_get_resource() and devm_ioremap_resource()
separately

Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add Mellanox BlueField Gigabit Ethernet driver

This patch adds build and driver logic for the "mlxbf_gige"
Ethernet driver from Mellanox Technologies. The second
generation BlueField SoC from Mellanox supports an
out-of-band GigaBit Ethernet management port to the Arm
subsystem. This driver supports TCP/IP network connectivity
for that port, and provides back-end routines to handle
basic ethtool requests.

The driver interfaces to the Gigabit Ethernet block of
BlueField SoC via MMIO accesses to registers, which contain
control information or pointers describing transmit and
receive resources. There is a single transmit queue, and
the port supports transmit ring sizes of 4 to 256 entries.
There is a single receive queue, and the port supports
receive ring sizes of 32 to 32K entries. The transmit and
receive rings are allocated from DMA coherent memory. There
is a 16-bit producer and consumer index per ring to denote
software ownership and hardware ownership, respectively.

The main driver logic such as probe(), remove(), and netdev
ops are in "mlxbf_gige_main.c". Logic in "mlxbf_gige_rx.c"
and "mlxbf_gige_tx.c" handles the packet processing for
receive and transmit respectively.

The logic in "mlxbf_gige_ethtool.c" supports the handling
of some basic ethtool requests: get driver info, get ring
parameters, get registers, and get statistics.

The logic in "mlxbf_gige_mdio.c" is the driver controlling
the Mellanox BlueField hardware that interacts with a PHY
device via MDIO/MDC pins. This driver does the following:
- At driver probe time, it configures several BlueField MDIO
parameters such as sample rate, full drive, voltage and MDC
- It defines functions to read and write MDIO registers and
registers the MDIO bus.
- It defines the phy interrupt handler reporting a
link up/down status change
- This driver's probe is invoked from the main driver logic
while the phy interrupt handler is registered in ndo_open.

Driver limitations
- Only supports 1Gbps speed
- Only supports GMII protocol
- Supports maximum packet size of 2KB
- Does not support scatter-gather buffering

Testing
- Successful build of kernel for ARM64, ARM32, X86_64
- Tested ARM64 build on FastModels & Palladium
- Tested ARM64 build on several Mellanox boards that are built with
the BlueField-2 SoC. The testing includes coverage in the areas
of networking (e.g. ping, iperf, ifconfig, route), file transfers
(e.g. SCP), and various ethtool options relevant to this driver.

Signed-off-by: David Thompson <davthompson@nvidia.com>
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Reviewed-by: Liming Sun <limings@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>