Re: tg3 pxe weirdness

[Siva Reddy Kallam <siva.kallam@broadcom.com>]

On Thu, Sep 21, 2017 at 7:53 PM, Berend De Schouwer
<berend.de.schouwer@gmail.com> wrote:
> Hi,
>
> I've got a machine with a Broadcom bcm5762c, using the tg3 driver, that
> fails to receive network packets under some very specific conditions.
>
> It works perfectly using a 1Gbps switch.  If, however, it first uses
> PXE and then loads the Linux tg3 driver, and the switch is 100Mbps, it
> no longer receives packets larger than ICMP.
>
> It does do ARP and ping.
>
> If it boots using PXE on a 1Gbps switch, boots into Linux, and then
> it's plugged into 100 Mbps it also stops receiving packets.
>
> mii-diag and dmesg confirm auto-negotiated speed and flow control, and
> confirm temporary disconnect as the cables are moved.
>
> PXE boots using UNDI, which then transfers a kernel using TFTP, which
> transfers correctly.  The kernel boots, loads the tg3 driver, connects
> the network.  Up to this point everything works.  Ping will work too.
> Any other network traffic fails.
>
> Booting from a harddrive works fine.  I assume the UNDI driver
> somewhere breaks auto-negotiation.  I've tried using mii-tool and
> ethtool, but I haven't managed to make it work yet.
>
> Is it possible to get negotiation working after PXE boot?  Are there
> any tg3 driver flags that might make a difference?
>
>
> Berend

Can you please share below details?
1) Model and Manufacturer of the system
2) Linux distro/kernel used?