[PATCH] ARM: dts: colibri-imx7: fix ethernet performance

Oleksandr Suvorov oleksandr.suvorov at toradex.com
Fri Jan 17 11:25:29 PST 2020


2mntnrs: please ignore this patchset.

On Thu, Jan 16, 2020 at 1:35 PM Lucas Stach <l.stach at pengutronix.de> wrote:
>
> On Do, 2020-01-16 at 10:13 +0000, Oleksandr Suvorov wrote:
> > Performance test of ethernet interface shows extremely low result:
> >
> > === w/o fix =================
> > Connecting to host 192.168.x.x, port 5201
> > [  5] local 192.168.x.y port59020 connected to 192.168.x.x port 5201
> > ...
> > [ ID] Interval           Transfer     Bitrate         Retr
> > [  5]   0.00-10.00  sec  2.78 MBytes  2.33 Mbits/sec  337      sender
> > [  5]   0.00-10.00  sec  2.66 MBytes  2.23
> > Mbits/sec           receiver
> > =============================
> >
> > Adding correct settings of the mdio bus with the respective phy
> > fixes this issue.
>
> So what's the actual issue being fixed here? High packet loss due to
> trying to force GBit speeds through 100MBit magnetics? So the addition
> of "max-speed = <100>;" is the real core of the fix?

Lucas, max-speed is not the core of this fix, actually, Micrel 8041 is
a 10/100 phy only.
But thank you for paying attention to this patchset. This is just a
part of a fix,
and it was mistakenly posted partially and with messed commit log.
I'll resend a complete solution when it is ready and retested again.

> The commit log should mention this.
>
> Regards,
> Lucas
>
> >
> > === after fix ===============
> > iperf3 -c 192.168.x.x
> > Connecting to host 192.168.x.x, port 5201
> > [  5] local 192.168.x.y port 50702 connected to 192.168.x.x port 5201
> > ...
> > [ ID] Interval           Transfer     Bitrate         Retr
> > [  5]   0.00-10.00  sec   114 MBytes  95.4 Mbits/sec   56      sender
> > [  5]   0.00-10.00  sec   112 MBytes  94.1
> > Mbits/sec           receiver
> > =============================
> >
> > Fixed: commit b326629f25b7 ("ARM: dts: imx7: add Toradex Colibri
> >                     iMX7S/iMX7D support")
> > Signed-off-by: Marcel Ziswiler <marcel.ziswiler at toradex.com>
> > Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov at toradex.com>
> >
> > ---
> >
> >  arch/arm/boot/dts/imx7-colibri.dtsi | 13 +++++++++++++
> >  1 file changed, 13 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/imx7-colibri.dtsi
> > b/arch/arm/boot/dts/imx7-colibri.dtsi
> > index d05be3f0e2a7..7b6a7c124345 100644
> > --- a/arch/arm/boot/dts/imx7-colibri.dtsi
> > +++ b/arch/arm/boot/dts/imx7-colibri.dtsi
> > @@ -115,7 +115,20 @@ &fec1 {
> >       assigned-clock-rates = <0>, <100000000>;
> >       phy-mode = "rmii";
> >       phy-supply = <&reg_LDO1>;
> > +     phy-handle = <&ethphy0>;
> >       fsl,magic-packet;
> > +
> > +     mdio {
> > +             #address-cells = <1>;
> > +             #size-cells = <0>;
> > +
> > +             ethphy0: ethernet-phy at 0 {
> > +                     compatible = "ethernet-phy-ieee802.3-c22";
> > +                     max-speed = <100>;
> > +                     micrel,led-mode = <0>;
> > +                     reg = <0>;
> > +             };
> > +     };
> >  };
> >
> >  &flexcan1 {
>


-- 
Best regards
Oleksandr Suvorov

Toradex AG
Altsagenstrasse 5 | 6048 Horw/Luzern | Switzerland | T: +41 41 500
4800 (main line)


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