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Date:   Mon, 29 Mar 2021 09:51:50 +0800
From:   Shawn Guo <shawnguo@kernel.org>
To:     Heiko Thiery <heiko.thiery@gmail.com>
Cc:     devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, Rob Herring <robh+dt@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        Michael Walle <michael@walle.cc>
Subject: Re: [PATCH v2] arm64: dts: imx8mq-kontron-pitx-imx8m: pass phy reset
 delays
Message-ID: <20210329015149.GL22955@dragon>
References: <20210323140019.14388-1-heiko.thiery@gmail.com>
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On Tue, Mar 23, 2021 at 03:00:21PM +0100, Heiko Thiery wrote:
> The TI DP83867 PHY datasheet says:
> T1: Post RESET stabilization time == 195us
> T3: Hardware configuration pins transition to output drivers == 64us
> T4: RESET pulse width == 1us
> 
> So with a little overhead set 'reset-assert-us' to 10us (T4) and
> 'reset-deassert-us' to 280us (T1+T3).
> 
> Without these reset delays the board will hang during startup when
> bootargs has ip=dhcp set.
> 
> Fixes: 1dc7f3d79a1a ("arm64: dts: fsl: add support for Kontron pitx-imx8m board")
> Signed-off-by: Heiko Thiery <heiko.thiery@gmail.com>
> ---
> v2:
>  - add desciption what issue will be fixed
>  - add Fixes tag

My branch is not a stable one, so I just squashed it into the original
commit.

Shawn