[FS#616] Ethernet port fails to receive traffic if traffic was received during init

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - syoder89 (syoder89) 

Attached to Project - LEDE Project
Summary - Ethernet port fails to receive traffic if traffic was received during init
Task Type - Bug Report
Category - Kernel
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - High
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - Symptoms: Fails to receive address via DHCP on WAN port
Board: WPJ558
Lede ver: 92b5b360fe39a4e446742ab3de9d0b2f91991d46  (Mar 7, 2017)
Steps to reproduce: ping -f wan_port_ip from another machine, reboot WPJ558

I have tracked the problem down to commit https://github.com/lede-project/source/commit/94e4ee5395b437e9ddaec8cdea47c1a4a9ba0c01 , more specifically enabling flow control on ports 1-5.

The problem goes away if I comment out line 693 from the patch:

+		t |= AR8216_PORT_STATUS_FLOW_CONTROL;

Funny how this caused the problem it was trying to solve...

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=616