changes v3:
- add missing ETHTOOL_A_LINKSTATE_MSE_* yaml changes
changes v2:
- rebase on latest net-next
This series introduces a generic kernel-userspace API for retrieving PHY
Mean Square Error (MSE) diagnostics, together with netlink integration,
a fast-path reporting hook in LINKSTATE_GET, and initial driver
implementations for the KSZ9477 and DP83TD510E PHYs.
MSE is defined by the OPEN Alliance "Advanced diagnostic features for
100BASE-T1 automotive Ethernet PHYs" specification [1] as a measure of
slicer error rate, typically used internally to derive the Signal
Quality Indicator (SQI). While SQI is useful as a normalized quality
index, it hides raw measurement data, varies in scaling and thresholds
between vendors, and may not indicate certain failure modes - for
example, cases where autonegotiation would fail even though SQI reports
a good link. In practice, such scenarios can only be investigated in
fixed-link mode; here, MSE can provide an empirically estimated value
indicating conditions under which autonegotiation would not succeed.
Example output with current implementation:
root@DistroKit:~ ethtool lan1
Settings for lan1:
...
Speed: 1000Mb/s
Duplex: Full
...
Link detected: yes
SQI: 5/7
MSE: 3/127 (channel: worst)
root@DistroKit:~ ethtool --show-mse lan1
MSE diagnostics for lan1:
MSE Configuration:
Max Average MSE: 127
Refresh Rate: 2000000 ps
Symbols per Sample: 250
Supported capabilities: average channel-a channel-b channel-c
channel-d worst
MSE Snapshot (Channel: a):
Average MSE: 4
MSE Snapshot (Channel: b):
Average MSE: 3
MSE Snapshot (Channel: c):
Average MSE: 2
MSE Snapshot (Channel: d):
Average MSE: 3
[1] https://opensig.org/wp-content/uploads/2024/01/Advanced_PHY_features_for_automotive_Ethernet_V1.0.pdf
Oleksij Rempel (5):
ethtool: introduce core UAPI and driver API for PHY MSE diagnostics
ethtool: netlink: add ETHTOOL_MSG_MSE_GET and wire up PHY MSE access
ethtool: netlink: add lightweight MSE reporting to LINKSTATE_GET
net: phy: micrel: add MSE interface support for KSZ9477 family
net: phy: dp83td510: add MSE interface support for 10BASE-T1L
Documentation/netlink/specs/ethtool.yaml | 175 +++++++++
Documentation/networking/ethtool-netlink.rst | 74 ++++
drivers/net/phy/dp83td510.c | 44 +++
drivers/net/phy/micrel.c | 76 ++++
include/linux/phy.h | 126 ++++++
.../uapi/linux/ethtool_netlink_generated.h | 94 +++++
net/ethtool/Makefile | 2 +-
net/ethtool/linkstate.c | 84 ++++
net/ethtool/mse.c | 362 ++++++++++++++++++
net/ethtool/netlink.c | 10 +
net/ethtool/netlink.h | 2 +
11 files changed, 1048 insertions(+), 1 deletion(-)
create mode 100644 net/ethtool/mse.c
--
2.39.5
