stmmac/RTL8211F/Meson GXBB: TX throughput problems

[jbrunet@baylibre.com (Jerome Brunet)]

On Thu, 2016-11-17 at 19:44 +0100, Andr? Roth wrote:
> Hi all,
> 
> > 
> > I checked again the kernel
> > at?https://github.com/hardkernel/linux/tree/ odroidc2-3.14.y. The
> > version you mention (3.14.65-73) seems to be:
> > sha1:?c75d5f4d1516cdd86d90a9d1c565bb0ed9251036 tag: jenkins-deb
> > s905
> > kernel-73
> 
> I downloaded the prebuilt image from hardkernel, I did not build the
> kernel myself. but hardkernel has an earlier release of the same
> kernel
> version, which works fine too. I assume they would have committed the
> change in the newer version..
> ?
> > 
> > In this particular version, both realtek drivers:
> > - drivers/net/phy/realtek.c
> > - drivers/amlogic/ethernet/phy/am_realtek.c
> > 
> > have the hack to disable 1000M advertisement. I don't understand
> > how
> > it possible for you to have 1000Base-T Full Duplex with this, maybe
> > I'm missing something here ?
> 
> that's what I don't understand as well...
> 
> the patched kernel shows the following:
> 
> $ uname -a
> Linux T-06 4.9.0-rc4+ #21 SMP PREEMPT Sun Nov 13 12:07:19 UTC 2016
> 
> $ sudo ethtool eth0
> Settings for eth0:
> ????????Supported ports: [ TP MII ]
> ????????Supported link modes:???10baseT/Half 10baseT/Full?
> ????????????????????????????????100baseT/Half 100baseT/Full?
> ????????????????????????????????1000baseT/Full?
> ????????Supported pause frame use: No
> ????????Supports auto-negotiation: Yes
> ????????Advertised link modes:??10baseT/Half 10baseT/Full?
> ????????????????????????????????100baseT/Half 100baseT/Full?
> ????????????????????????????????1000baseT/Full?
> ????????Advertised pause frame use: No
> ????????Advertised auto-negotiation: Yes
> ????????Link partner advertised link modes:??10baseT/Half
> 10baseT/Full?
> ?????????????????????????????????????????????100baseT/Half
> 100baseT/Full 1000baseT/Half 1000baseT/Full?
> ????????Link partner advertised pause frame use: Symmetric Receive-
> only
> ????????Link partner advertised auto-negotiation: Yes
> ????????Speed: 1000Mb/s
> ????????Duplex: Full
> ????????Port: MII
> ????????PHYAD: 0
> ????????Transceiver: external
> ????????Auto-negotiation: on
> ????????Supports Wake-on: ug
> ????????Wake-on: d
> ????????Current message level: 0x0000003f (63)
> ???????????????????????????????drv probe link timer ifdown ifup
> ????????Link detected: yes
> 
> $ sudo ethtool --show-eee eth0
> EEE Settings for eth0:
> ????????EEE status: disabled
> ????????Tx LPI: disabled
> ????????Supported EEE link modes:??100baseT/Full?
> ???????????????????????????????????1000baseT/Full?
> ????????Advertised EEE link modes:??100baseT/Full?
> ????????Link partner advertised EEE link modes:??100baseT/Full?
> ?????????????????????????????????????????????????1000baseT/Full?
> 
> can it be that "EEE link modes" and the "normal" link modes are two
> different things ??

Exactly, They are.
Hardkernel code disable both.

With hardkernel's kernel, you should not have?1000baseT/Full in
"Advertised link modes" and you would have nothing reported in
"Advertised EEE link modes"

> 
> > 
> > If you did compile the kernel yourself, could you check the 2 file
> > mentioned above ? Just to be sure there was no patch applied at the
> > last minute, which would not show up in the git history of
> > hardkernel ?
> 
> I cannot check this easily at the moment..
> 
> Regards,
> 
> ?Andr?
>