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From:   Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Date:   Fri, 25 Sep 2020 09:41:13 +0200
Message-ID: <CAFBinCAJ6svwiv9OM6EHz7468D9h+jW_ULiGrorgLetcODsAKQ@mail.gmail.com>
Subject: Re: [PATCH 5/8] arm64: dts: meson: remove reset-gpios from ethernet
 node for VIM2 meson-gxm-khadas-vim2
To:     Artem Lapkin <email2tema@gmail.com>
Cc:     Neil Armstrong <narmstrong@baylibre.com>, khilman@baylibre.com,
        robh+dt@kernel.org, jbrunet@baylibre.com,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-amlogic@lists.infradead.org, linux-kernel@vger.kernel.org,
        art@khadas.com, nick@khadas.com, gouwa@khadas.com
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Hello Artem,

On Fri, Sep 25, 2020 at 5:31 AM Artem Lapkin <email2tema@gmail.com> wrote:
>
> 1) fix down/up ethernet interface - need remove reset-gpios for ethernet node
>
> `ifconfig eth0 down && ifconfig eth0 up` # didnt works with reset-gpios
what is the problem that you observe here?
did you investigate further why resetting the PHY changes this?

the problem I see with removing the reset-gpios is that we cannot
fully reset the PHY into a defined state
some of the registers are kept with a soft-reset

> 2) add max-speed 1Gbit
my understanding is that max-speed is needed when (in this case) the
PHY advertises a higher speed than the hardware is actually capable of
(for whatever reason)
what is the problem that you have seen when max-speed was not set?


Best regards,
Martin