net: ethernet: Add missing depends on MDIO_DEVRES

A number of MDIO drivers make use of devm_mdiobus_alloc_size(). This
is only available when CONFIG_MDIO_DEVRES is enabled. Add missing
depends or selects, depending on if there are circular dependencies or
not. This avoids linker errors, especially for randconfig builds.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20230409150204.2346231-1-andrew@lunn.ch
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: enetc: build common object files into a separate module

The build system is complaining about the following:

enetc.o is added to multiple modules: fsl-enetc fsl-enetc-vf
enetc_cbdr.o is added to multiple modules: fsl-enetc fsl-enetc-vf
enetc_ethtool.o is added to multiple modules: fsl-enetc fsl-enetc-vf

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

net: remove redundant config PCI dependency for some network driver configs

While reviewing dependencies in some Kconfig files, I noticed the redundant
dependency "depends on PCI && PCI_MSI". The config PCI_MSI has always,
since its introduction, been dependent on the config PCI. So, it is
sufficient to just depend on PCI_MSI, and know that the dependency on PCI
is implicitly implied.

Reduce the dependencies of some network driver configs.
No functional change and effective change of Kconfig dependendencies.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Dimitris Michailidis <dmichail@fungible.com>
Link: https://lore.kernel.org/r/20230111125855.19020-1-lukas.bulwahn@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: enetc: automatically select IERB module

Now that enetc supports flow control we have to make sure the settings in
the IERB are correct. Therefore, we actually depend on the enetc-ierb
module. Previously it was possible that this module was disabled while the
enetc was enabled. Fix it by automatically select the enetc-ierb module.

Fixes: e7d48e5fbf30 ("net: enetc: add a mini driver for the Integrated Endpoint Register Block")
Signed-off-by: Michael Walle <michael@walle.cc>
Acked-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: enetc: add a mini driver for the Integrated Endpoint Register Block

The NXP ENETC is a 4-port Ethernet controller which 'smells' to
operating systems like 4 distinct PCIe PFs with SR-IOV, each PF having
its own driver instance, but in fact there are some hardware resources
which are shared between all ports, like for example the 256 KB SRAM
FIFO between the MACs and the Host Transfer Agent which DMAs frames to
DRAM.

To hide the stuff that cannot be neatly exposed per port, the hardware
designers came up with this idea of having a dedicated register block
which is supposed to be populated by the bootloader, and contains
everything configuration-related: MAC addresses, FIFO partitioning, etc.

When a port is reset using PCIe Function Level Reset, its defaults are
transferred from the IERB configuration. Most of the time, the settings
made through the IERB are read-only in the port's memory space (if they
are even visible), so they cannot be modified at runtime.

Linux doesn't have any advanced FIFO partitioning requirements at all,
but when reading through the hardware manual, it became clear that, even
though there are many good 'recommendations' for default values, many of
them were not actually put in practice on LS1028A. So we end up with a
default configuration that:

(a) does not have enough TX and RX byte credits to support the max MTU
of 9600 (which the Linux driver claims already) properly (at full speed)
(b) allows the FIFO to be overrun with RX traffic, potentially
overwriting internal data structures.

The last part sounds a bit catastrophic, but it isn't. Frames are
supposed to transit the FIFO for a very short time, but they can
actually accumulate there under 2 conditions:

(a) there is very severe congestion on DRAM memory, or
(b) the RX rings visible to the operating system were configured for
lossless operation, and they just ran out of free buffers to copy
the frame to. This is what is used to put backpressure onto the MAC
with flow control.

So since ENETC has not supported flow control thus far, RX FIFO overruns
were never seen with Linux. But with the addition of flow control, we
should configure some registers to prevent this from happening. What we
are trying to protect against are bad actors which continue to send us
traffic despite the fact that we have signaled a PAUSE condition. Of
course we can't be lossless in that case, but it is best to configure
the FIFO to do tail dropping rather than letting it overrun.

So in a nutshell, this driver is a fixup for all the IERB default values
that should have been but aren't.

The IERB configuration needs to be done _before_ the PFs are enabled.
So every PF searches for the presence of the "fsl,ls1028a-enetc-ierb"
node in the device tree, and if it finds it, it "registers" with the
IERB, which means that it requests the IERB to fix up its default
values. This is done through -EPROBE_DEFER. The IERB driver is part of
the fsl_enetc module, but is technically a platform driver, since the
IERB is a good old fashioned MMIO region, as opposed to ENETC ports
which pretend to be PCIe devices.

The driver was already configuring ENETC_PTXMBAR (FIFO allocation for
TX) because due to an omission, TXMBAR is a read/write register in the
PF memory space. But the manual is quite clear that the formula for this
should depend upon the TX byte credits (TXBCR). In turn, the TX byte
credits are only readable/writable through the IERB. So if we want to
ensure that the TXBCR register also has a value that is correct and in
line with TXMBAR, there is simply no way this can be done from the PF
driver, access to the IERB is needed.

I could have modified U-Boot to fix up the IERB values, but that is
quite undesirable, as old U-Boot versions are likely to be floating
around for quite some time from now.

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

enetc: auto select PHYLIB and MDIO_DEVRES

FSL_ENETC_MDIO use symbols from PHYLIB (MDIO_BUS) and MDIO_DEVRES,
however there are no dependency specified in Kconfig

ERROR: modpost: "__mdiobus_register" [drivers/net/ethernet/freescale/enetc/fsl-enetc-mdio.ko] undefined!
ERROR: modpost: "mdiobus_unregister" [drivers/net/ethernet/freescale/enetc/fsl-enetc-mdio.ko] undefined!
ERROR: modpost: "devm_mdiobus_alloc_size" [drivers/net/ethernet/freescale/enetc/fsl-enetc-mdio.ko] undefined!

add depends on MDIO_DEVRES && MDIO_BUS

Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: Workaround for MDIO register access issue

Due to a hardware issue, an access to MDIO registers
that is concurrent with other ENETC register accesses
may lead to the MDIO access being dropped or corrupted.
The workaround introduces locking for all register accesses
to the ENETC register space. To reduce performance impact,
a readers-writers locking scheme has been implemented.
The writer in this case is the MDIO access code (irrelevant
whether that MDIO access is a register read or write), and
the reader is any access code to non-MDIO ENETC registers.
Also, the datapath functions acquire the read lock fewer times
and use _hot accessors. All the rest of the code uses the _wa
accessors which lock every register access.
The commit introducing MDIO support is -
commit ebfcb23d62ab ("enetc: Add ENETC PF level external MDIO support")
but due to subsequent refactoring this patch is applicable on
top of a later commit.

Fixes: 6517798dd343 ("enetc: Make MDIO accessors more generic and export to include/linux/fsl")
Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Link: https://lore.kernel.org/r/20201112182608.26177-1-claudiu.manoil@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

enetc: Migrate to PHYLINK and PCS_LYNX

This is a methodical transition of the driver from phylib
to phylink, following the guidelines from sfp-phylink.rst.
The MAC register configurations based on interface mode
were moved from the probing path to the mac_config() hook.
MAC enable and disable commands (enabling Rx and Tx paths
at MAC level) were also extracted and assigned to their
corresponding phylink hooks.
As part of the migration to phylink, the serdes configuration
from the driver was offloaded to the PCS_LYNX module,
introduced in commit 0da4c3d393e4 ("net: phy: add Lynx PCS module"),
the PCS_LYNX module being a mandatory component required to
make the enetc driver work with phylink.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Reviewed-by: Ioana Ciornei <ioana.cionei@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

enetc: Add adaptive interrupt coalescing

Use the generic dynamic interrupt moderation (dim)
framework to implement adaptive interrupt coalescing
on Rx. With the per-packet interrupt scheme, a high
interrupt rate has been noted for moderate traffic flows
leading to high CPU utilization. The 'dim' scheme
implemented by the current patch addresses this issue
improving CPU utilization while using minimal coalescing
time thresholds in order to preserve a good latency.
On the Tx side use an optimal time threshold value by
default. This value has been optimized for Tx TCP
streams at a rate of around 85kpps on a 1G link,
at which rate half of the Tx ring size (128) gets filled
in 1500 usecs. Scaling this down to 2.5G links yields
the current value of 600 usecs, which is conservative
and gives good enough results for 1G links too (see
next).

Below are some measurement results for before and after
this patch (and related dependencies) basically, for a
2 ARM Cortex-A72 @1.3Ghz CPUs system (32 KB L1 data cache),
using 60secs log netperf TCP stream tests @ 1Gbit link
(maximum throughput):

1) 1 Rx TCP flow, both Rx and Tx processed by the same NAPI
thread on the same CPU:
CPU utilization int rate (ints/sec)
Before: 50%-60% (over 50%) 92k
After: 13%-22% 3.5k-12k
Comment: Major CPU utilization improvement for a single flow
Rx TCP flow (i.e. netperf -t TCP_MAERTS) on a single
CPU. Usually settles under 16% for longer tests.

2) 4 Rx TCP flows + 4 Tx TCP flows (+ pings to check the latency):
Total CPU utilization Total int rate (ints/sec)
Before: ~80% (spikes to 90%) ~100k
After: 60% (more steady) ~4k
Comment: Important improvement for this load test, while the
ping test outcome does not show any notable
difference compared to before.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: Add dynamic allocation of extended Rx BD rings

Hardware timestamping support (PTP) on Rx requires extended
buffer descriptors, double the size of normal Rx descriptors.
On the current controller revision only the timestamping offload
requires extended Rx descriptors.
Since Rx timestamping can be turned on/off at runtime, make Rx ring
allocation configurable at runtime too. As a result, the static
config option FSL_ENETC_HW_TIMESTAMPING can be dropped and the
extended descriptors can be used only when Rx timestamping gets
activated.
The extension has the same size as the base descriptor, making
the descriptor iterators easy to update for the extended case.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: remove "depends on (ARCH_LAYERSCAPE || COMPILE_TEST)"

ARCH_LAYERSCAPE isn't needed for this driver, it builds and
sends/receives traffic without this config option just fine.

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

enetc: Make MDIO accessors more generic and export to include/linux/fsl

Within the LS1028A SoC, the register map for the ENETC MDIO controller
is instantiated a few times: for the central (external) MDIO controller,
for the internal bus of each standalone ENETC port, and for the internal
bus of the Felix switch.

Refactoring is needed to support multiple MDIO buses from multiple
drivers. The enetc_hw structure is made an opaque type and a smaller
enetc_mdio_priv is created.

'mdio_base' - MDIO registers base address - is being parameterized, to
be able to work with different MDIO register bases.

The ENETC MDIO bus operations are exported from the fsl-enetc-mdio
kernel object, the same that registers the central MDIO controller (the
dedicated PF). The ENETC main driver has been changed to select it, and
use its exported helpers to further register its private MDIO bus. The
DSA Felix driver will do the same.

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

enetc: add support Credit Based Shaper(CBS) for hardware offload

The ENETC hardware support the Credit Based Shaper(CBS) which part
of the IEEE-802.1Qav. The CBS driver was loaded by the sch_cbs
interface when set in the QOS in the kernel.

Here is an example command to set 20Mbits bandwidth in 1Gbits port
for taffic class 7:

tc qdisc add dev eth0 root handle 1: mqprio \
num_tc 8 map 0 1 2 3 4 5 6 7 hw 1

tc qdisc replace dev eth0 parent 1:8 cbs \
locredit -1470 hicredit 30 \
sendslope -980000 idleslope 20000 offload 1

Signed-off-by: Po Liu <Po.Liu@nxp.com>
Reviewed-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: Configure the Time-Aware Scheduler via tc-taprio offload

ENETC supports in hardware for time-based egress shaping according
to IEEE 802.1Qbv. This patch implement the Qbv enablement by the
hardware offload method qdisc tc-taprio method.
Also update cbdr writeback to up level since control bd ring may
writeback data to control bd ring.

Signed-off-by: Po Liu <Po.Liu@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: Add mdio bus driver for the PCIe MDIO endpoint

ENETC ports can manage the MDIO bus via local register
interface. However there's also a centralized way
to manage the MDIO bus, via the MDIO PCIe endpoint
device integrated by the same root complex that also
integrates the ENETC ports (eth controllers).

Depending on board design and use case, centralized
access to MDIO may be better than using local ENETC
port registers. For instance, on the LS1028A QDS board
where MDIO muxing is required. Also, the LS1028A on-chip
switch doesn't have a local MDIO register interface.

The current patch registers the above PCIe endpoint as a
separate MDIO bus and provides a driver for it by re-using
the code used for local MDIO access. It also allows the
ENETC port PHYs to be managed by this driver if the local
"mdio" node is missing from the ENETC port node.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: Select PHYLIB while CONFIG_FSL_ENETC_VF is set

Like FSL_ENETC, when CONFIG_FSL_ENETC_VF is set,
we should select PHYLIB, otherwise building still fails:

drivers/net/ethernet/freescale/enetc/enetc.o: In function `enetc_open':
enetc.c:(.text+0x2744): undefined reference to `phy_start'
enetc.c:(.text+0x282c): undefined reference to `phy_disconnect'
drivers/net/ethernet/freescale/enetc/enetc.o: In function `enetc_close':
enetc.c:(.text+0x28f8): undefined reference to `phy_stop'
enetc.c:(.text+0x2904): undefined reference to `phy_disconnect'
drivers/net/ethernet/freescale/enetc/enetc_ethtool.o:(.rodata+0x3f8): undefined reference to `phy_ethtool_get_link_ksettings'
drivers/net/ethernet/freescale/enetc/enetc_ethtool.o:(.rodata+0x400): undefined reference to `phy_ethtool_set_link_ksettings'

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: d4fd0404c1c9 ("enetc: Introduce basic PF and VF ENETC ethernet drivers")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: Fix build error without PHYLIB

If PHYLIB is not set, build enetc will fails:

drivers/net/ethernet/freescale/enetc/enetc.o: In function `enetc_open':
enetc.c: undefined reference to `phy_disconnect'
enetc.c: undefined reference to `phy_start'
drivers/net/ethernet/freescale/enetc/enetc.o: In function `enetc_close':
enetc.c: undefined reference to `phy_stop'
enetc.c: undefined reference to `phy_disconnect'
drivers/net/ethernet/freescale/enetc/enetc_ethtool.o: undefined reference to `phy_ethtool_get_link_ksettings'
drivers/net/ethernet/freescale/enetc/enetc_ethtool.o: undefined reference to `phy_ethtool_set_link_ksettings'
drivers/net/ethernet/freescale/enetc/enetc_mdio.o: In function `enetc_mdio_probe':
enetc_mdio.c: undefined reference to `mdiobus_alloc_size'
enetc_mdio.c: undefined reference to `mdiobus_free'

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: d4fd0404c1c9 ("enetc: Introduce basic PF and VF ENETC ethernet drivers")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: add hardware timestamping support

This patch is to add hardware timestamping support
for ENETC. On Rx, timestamping is enabled for all
frames. On Tx, we only instruct the hardware to
timestamp the frames marked accordingly by the stack.

Because the RX BD ring dynamic allocation has not been
supported and it is too expensive to use extended RX BDs
if timestamping is not used, a Kconfig option is used to
enable extended RX BDs in order to support hardware
timestamping. This option will be removed once RX BD
ring dynamic allocation is implemented.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: add PTP clock driver

This patch is to add PTP clock driver for ENETC.
The driver reused QorIQ PTP clock driver.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

enetc: Introduce basic PF and VF ENETC ethernet drivers

ENETC is a multi-port virtualized Ethernet controller supporting GbE
designs and Time-Sensitive Networking (TSN) functionality.
ENETC is operating as an SR-IOV multi-PF capable Root Complex Integrated
Endpoint (RCIE). As such, it contains multiple physical (PF) and
virtual (VF) PCIe functions, discoverable by standard PCI Express.

Introduce basic PF and VF ENETC ethernet drivers. The PF has access to
the ENETC Port registers and resources and makes the required privileged
configurations for the underlying VF devices. Common functionality is
controlled through so called System Interface (SI) register blocks, PFs
and VFs own a SI each. Though SI register blocks are almost identical,
there are a few privileged SI level controls that are accessible only to
PFs, and so the distinction is made between PF SIs (PSI) and VF SIs (VSI).
As such, the bulk of the code, including datapath processing, basic h/w
offload support and generic pci related configuration, is shared between
the 2 drivers and is factored out in common source files (i.e. enetc.c).

Major functionalities included (for both drivers):
MSI-X support for Rx and Tx processing, assignment of Rx/Tx BD ring pairs
to MSI-X entries, multi-queue support, Rx S/G (Rx frame fragmentation) and
jumbo frame (up to 9600B) support, Rx paged allocation and reuse, Tx S/G
support (NETIF_F_SG), Rx and Tx checksum offload, PF MAC filtering and
initial control ring support, VLAN extraction/ insertion, PF Rx VLAN
CTAG filtering, VF mac address config support, VF VLAN isolation support,
etc.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>