kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-11-10 20:48:12 +00:00
Code Issues Releases Packages Activity

Merge branch 'net-enetc-restore-rx-ring-congestion-mode-after-ring-reconfiguration'

Browse source 
Wei Fang says:

====================
net: enetc: restore RX ring congestion mode after ring reconfiguration

The RX BD ring congestion mode (CM) enables the ENETC MAC to generate
PAUSE frames when ingress congestion occurs. It is configured only in
the phylink .mac_link_up() callback, which is invoked when the link
status changes.

However, enetc_reconfigure() tears down and re-creates the RX BD rings
at runtime without any link status change, for example when enabling or
disabling PTP RX hardware timestamping. enetc_setup_rxbdr() rebuilds the
RBMR register from zero, which clears the CM bit, and since the link
status does not change, .mac_link_up() is not called again to restore
it. As a result, flow control silently stops working after such a
reconfiguration.

To solve this issue, track the desired CM state in a software flag
ENETC_RXBDR_CM, which is maintained by the .mac_link_up() /
.mac_link_down() callbacks and consulted by enetc_setup_rxbdr() when the
RX BD rings are (re)configured. Both ENETC v1 and ENETC v4 are affected
and are fixed in the same way.
====================

Link: https://patch.msgid.link/20260821064140.1315611-1-wei.fang@oss.nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Jakub Kicinski 2026-08-24 11:56:39 -07:00
commit 01ba856c36
4 changed files with 72 additions and 39 deletions
Download patch file Download diff file Expand all files Collapse all files