linux/include
Vidya Sagar Ravipati 1a5f3da20b net: ethtool: add support for forward error correction modes
Forward Error Correction (FEC) modes i.e Base-R
and Reed-Solomon modes are introduced in 25G/40G/100G standards
for providing good BER at high speeds. Various networking devices
which support 25G/40G/100G provides ability to manage supported FEC
modes and the lack of FEC encoding control and reporting today is a
source for interoperability issues for many vendors.
FEC capability as well as specific FEC mode i.e. Base-R
or RS modes can be requested or advertised through bits D44:47 of
base link codeword.

This patch set intends to provide option under ethtool to manage
and report FEC encoding settings for networking devices as per
IEEE 802.3 bj, bm and by specs.

set-fec/show-fec option(s) are designed to provide control and
report the FEC encoding on the link.

SET FEC option:
root@tor: ethtool --set-fec  swp1 encoding [off | RS | BaseR | auto]

Encoding: Types of encoding
Off    :  Turning off any encoding
RS     :  enforcing RS-FEC encoding on supported speeds
BaseR  :  enforcing Base R encoding on supported speeds
Auto   :  IEEE defaults for the speed/medium combination

Here are a few examples of what we would expect if encoding=auto:
- if autoneg is on, we are  expecting FEC to be negotiated as on or off
  as long as protocol supports it
- if the hardware is capable of detecting the FEC encoding on it's
      receiver it will reconfigure its encoder to match
- in absence of the above, the configuration would be set to IEEE
  defaults.

>From our  understanding , this is essentially what most hardware/driver
combinations are doing today in the absence of a way for users to
control the behavior.

SHOW FEC option:
root@tor: ethtool --show-fec  swp1
FEC parameters for swp1:
Active FEC encodings: RS
Configured FEC encodings:  RS | BaseR

ETHTOOL DEVNAME output modification:

ethtool devname output:
root@tor:~# ethtool swp1
Settings for swp1:
root@hpe-7712-03:~# ethtool swp18
Settings for swp18:
    Supported ports: [ FIBRE ]
    Supported link modes:   40000baseCR4/Full
                            40000baseSR4/Full
                            40000baseLR4/Full
                            100000baseSR4/Full
                            100000baseCR4/Full
                            100000baseLR4_ER4/Full
    Supported pause frame use: No
    Supports auto-negotiation: Yes
    Supported FEC modes: [RS | BaseR | None | Not reported]
    Advertised link modes:  Not reported
    Advertised pause frame use: No
    Advertised auto-negotiation: No
    Advertised FEC modes: [RS | BaseR | None | Not reported]
<<<< One or more FEC modes
    Speed: 100000Mb/s
    Duplex: Full
    Port: FIBRE
    PHYAD: 106
    Transceiver: internal
    Auto-negotiation: off
    Link detected: yes

This patch includes following changes
a) New ETHTOOL_SFECPARAM/SFECPARAM API, handled by
  the new get_fecparam/set_fecparam callbacks, provides support
  for configuration of forward error correction modes.
b) Link mode bits for FEC modes i.e. None (No FEC mode), RS, BaseR/FC
  are defined so that users can configure these fec modes for supported
  and advertising fields as part of link autonegotiation.

Signed-off-by: Vidya Sagar Ravipati <vidya.chowdary@gmail.com>
Signed-off-by: Dustin Byford <dustin@cumulusnetworks.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-29 23:23:44 -07:00
..
acpi More ACPI updates for v4.13-rc1 2017-07-10 15:19:40 -07:00
asm-generic Merge branch 'work.uaccess-unaligned' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-15 11:17:52 -07:00
clocksource
crypto
drm i915, amd and some core fixes + mediatek color support 2017-07-13 11:26:18 -07:00
dt-bindings Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2017-07-15 10:59:54 -07:00
keys
kvm
linux net: ethtool: add support for forward error correction modes 2017-07-29 23:23:44 -07:00
math-emu
media main drm pull for v4.13 2017-07-09 18:48:37 -07:00
memory
misc cxl: Export library to support IBM XSL 2017-07-03 23:07:03 +10:00
net tcp: remove redundant argument from tcp_rcv_established() 2017-07-24 17:28:12 -07:00
pcmcia
ras
rdma IB/core: Remove NOIO QP create flag 2017-07-17 21:21:24 -04:00
scsi Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2017-07-13 14:27:32 -07:00
soc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-07-05 12:31:59 -07:00
sound ASoC: Updates for v4.13 2017-07-03 19:51:42 +02:00
target iscsi-target: Add login_keys_workaround attribute for non RFC initiators 2017-07-11 10:56:39 -07:00
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-07-21 03:38:43 +01:00
uapi net: ethtool: add support for forward error correction modes 2017-07-29 23:23:44 -07:00
video
xen This is the first pull request for the new dma-mapping subsystem 2017-07-06 19:20:54 -07:00