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

[Chenguang Zhao <chenguang.zhao@linux.dev>]

On Thu, Oct 22, 2026 at 03:56:50PM -0700, Florian Fainelli wrote:
> 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
> 

Hi Florian,

Please take a look at the issues Sashiko reported.

Thanks,
Chenguang