[PATCH net 0/6 RESEND] net: dsa: b53: PCS fixes

From: Florian Fainelli

Date: Thu Oct 22 2026 - 18:57:26 EST


This patch series fixes a number of issues found with a LLM and while
testing on a Broadcom Northstar Plus reference board (BCM958625HR) using
a SFP connected to a fiber converter:

- there was no serialization of the registers across multiple lanes
- the SerDes powering down was incorrectly managed and should have used
.pcs_{enable,disable}
- the interfaces advertisement should have been confined to successfully
initialized PCSes
- the negotation and forced link parameters were incorrectly supported
and should have used pcs_link_up and pcs_inband_caps
- link state should have been reported through the PCS

With these patches disconnecting the fiber cables triggers a link down,
as does disconnecting the fiber converter from its cable or powering it
down, ip link up/down also work properly as a result as well.

Florian Fainelli (6):
net: dsa: b53: serialize SerDes register transactions
net: dsa: b53: manage SerDes power through the PCS callbacks
net: dsa: b53: constrain SerDes interfaces to initialized PCSes
net: dsa: b53: configure PCS negotiation and forced link parameters
net: dsa: b53: report link state through the PCS
net: dsa: b53: apply resolved link settings to serial port MACs

drivers/net/dsa/b53/b53_common.c | 69 ++----
drivers/net/dsa/b53/b53_priv.h | 4 -
drivers/net/dsa/b53/b53_serdes.c | 407 +++++++++++++++++++++++--------
drivers/net/dsa/b53/b53_serdes.h | 13 +-
drivers/net/dsa/b53/b53_srab.c | 12 +-
5 files changed, 345 insertions(+), 160 deletions(-)

--
2.53.0