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  1. 19 Apr, 2021 12 commits
    • Vladimir Oltean's avatar
      net: enetc: add support for flow control · a8648887
      Vladimir Oltean authored 
      In the ENETC receive path, a frame received by the MAC is first stored
in a 256KB 'FIFO' memory, then transferred to DRAM when enqueuing it to
the RX ring. The FIFO is a shared resource for all ENETC ports, but
every port keeps track of its own memory utilization, on RX and on TX.

There is a setting for RX rings through which they can either operate in
'lossy' mode (where the lack of a free buffer causes an immediate
discard of the frame) or in 'lossless' mode (where the lack of a free
buffer in the ring makes the frame stay longer in the FIFO).

In turn, when the memory utilization of the FIFO exceeds a certain
margin, the MAC can be configured to emit PAUSE frames.

There is enough FIFO memory to buffer up to 3 MTU-sized frames per RX
port while not jeopardizing the other use cases (jumbo frames), and
also not consume bytes from the port TX allocations. Also, 3 MTU-sized
frames worth of memory is enough to ensure zero loss for 64 byte packets
at 1G line rate.
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: default avatarClaudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a8648887
    • Vladimir Oltean's avatar
      arm64: dts: ls1028a: declare the Integrated Endpoint Register Block node · b764dc6c
      Vladimir Oltean authored 
      Add a node describing the address in the SoC memory space for the IERB.
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b764dc6c
    • Vladimir Oltean's avatar
      net: enetc: add a mini driver for the Integrated Endpoint Register Block · e7d48e5f
      Vladimir Oltean authored 
      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: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e7d48e5f
    • Vladimir Oltean's avatar
      dt-bindings: net: fsl: enetc: add the IERB documentation · 4ac7acc6
      Vladimir Oltean authored 
      Mention the required compatible string and base address for the
Integrated Endpoint Register Block node.
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4ac7acc6
    • Vladimir Oltean's avatar
      net: enetc: create a common enetc_pf_to_port helper · 87614b93
      Vladimir Oltean authored 
      Even though ENETC interfaces are exposed as individual PCIe PFs with
their own driver instances, the ENETC is still fundamentally a
multi-port Ethernet controller, and some parts of the IP take a port
number (as can be seen in the PSFP implementation).

Create a common helper that can be used outside of the TSN code for
retrieving the ENETC port number based on the PF number. This is only
correct for LS1028A, the only Linux-capable instantiation of ENETC thus
far.

Note that ENETC port 3 is PF 6. The TSN code did not care about this
because ENETC port 3 does not support TSN, so the wrong mapping done by
enetc_get_port for PF 6 could have never been hit.
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      87614b93
    • Gustavo A. R. Silva's avatar
      ethtool: ioctl: Fix out-of-bounds warning in store_link_ksettings_for_user() · c1d9e34e
      Gustavo A. R. Silva authored 
      Fix the following out-of-bounds warning:

net/ethtool/ioctl.c:492:2: warning: 'memcpy' offset [49, 84] from the object at 'link_usettings' is out of the bounds of referenced subobject 'base' with type 'struct ethtool_link_settings' at offset 0 [-Warray-bounds]

The problem is that the original code is trying to copy data into a
some struct members adjacent to each other in a single call to
memcpy(). This causes a legitimate compiler warning because memcpy()
overruns the length of &link_usettings.base. Fix this by directly
using &link_usettings and _from_ as destination and source addresses,
instead.

This helps with the ongoing efforts to globally enable -Warray-bounds
and get us closer to being able to tighten the FORTIFY_SOURCE routines
on memcpy().

Link: https://github.com/KSPP/linux/issues/109Reported-by: default avatarkernel test robot <lkp@intel.com>
Signed-off-by: default avatarGustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c1d9e34e
    • Dexuan Cui's avatar
      net: mana: Add a driver for Microsoft Azure Network Adapter (MANA) · ca9c54d2
      Dexuan Cui authored 
      Add a VF driver for Microsoft Azure Network Adapter (MANA) that will be
available in the future.
Co-developed-by: default avatarHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: default avatarHaiyang Zhang <haiyangz@microsoft.com>
Co-developed-by: default avatarShachar Raindel <shacharr@microsoft.com>
Signed-off-by: default avatarShachar Raindel <shacharr@microsoft.com>
Signed-off-by: default avatarDexuan Cui <decui@microsoft.com>
Reviewed-by: default avatarStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ca9c54d2
    • Taehee Yoo's avatar
      mld: remove unnecessary prototypes · 83c1ca25
      Taehee Yoo authored 
      Some prototypes are unnecessary, so delete it.
Signed-off-by: default avatarTaehee Yoo <ap420073@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      83c1ca25
    • David S. Miller's avatar
      Merge branch 'nh-flushing' · c589fa10
      David S. Miller authored 
      Ido Schimmel says:

====================
nexthop: Support large scale nexthop flushing

Patch #1 fixes a day-one bug in the nexthop code and allows "ip nexthop
flush" to work correctly with large number of nexthops that do not fit
in a single-part dump.

Patch #2 adds a test case.

Targeting at net-next since this use case never worked, the flow is
pretty obscure and such a large number of nexthops is unlikely to be
used in any real-world scenario.

Tested with fib_nexthops.sh:

Tests passed: 219
Tests failed:   0
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c589fa10
    • Ido Schimmel's avatar
      selftests: fib_nexthops: Test large scale nexthop flushing · bf5eb67d
      Ido Schimmel authored 
      Test that all the nexthops are flushed when a multi-part nexthop dump is
required for the flushing.

Without previous patch:

 # ./fib_nexthops.sh
 TEST: Large scale nexthop flushing                                  [FAIL]

With previous patch:

 # ./fib_nexthops.sh
 TEST: Large scale nexthop flushing                                  [ OK ]
Signed-off-by: default avatarIdo Schimmel <idosch@nvidia.com>
Reviewed-by: default avatarPetr Machata <petrm@nvidia.com>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      bf5eb67d
    • Ido Schimmel's avatar
      nexthop: Restart nexthop dump based on last dumped nexthop identifier · 9e46fb65
      Ido Schimmel authored 
      Currently, a multi-part nexthop dump is restarted based on the number of
nexthops that have been dumped so far. This can result in a lot of
nexthops not being dumped when nexthops are simultaneously deleted:

 # ip nexthop | wc -l
 65536
 # ip nexthop flush
 Dump was interrupted and may be inconsistent.
 Flushed 36040 nexthops
 # ip nexthop | wc -l
 29496

Instead, restart the dump based on the nexthop identifier (fixed number)
of the last successfully dumped nexthop:

 # ip nexthop | wc -l
 65536
 # ip nexthop flush
 Dump was interrupted and may be inconsistent.
 Flushed 65536 nexthops
 # ip nexthop | wc -l
 0
Reported-by: default avatarMaksym Yaremchuk <maksymy@nvidia.com>
Tested-by: default avatarMaksym Yaremchuk <maksymy@nvidia.com>
Signed-off-by: default avatarIdo Schimmel <idosch@nvidia.com>
Reviewed-by: default avatarPetr Machata <petrm@nvidia.com>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9e46fb65
    • David S. Miller's avatar
      Merge tag 'wireless-drivers-next-2021-04-18' of... · 56aa7b21
      David S. Miller authored 
      Merge tag 'wireless-drivers-next-2021-04-18' of git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers-next

Kalle Valo says:

====================
wireless-drivers-next patches for v5.13

Second set of patches for v5.13. A lot of iwlwifi and mt76 patches
this time, and also smaller features and fixes all over.

mt76

* mt7915/mt7615 decapsulation offload support

* threaded NAPI support

* new device IDs

* mt7921 device reset support

* rx timestamp support

iwlwifi

* passive scan support for 6GHz

* new hardware support

wilc1000

* CRC support for SPI bus
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      56aa7b21
  3. 18 Apr, 2021 15 commits
  5. 17 Apr, 2021 13 commits
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