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Date:   Fri, 25 Jun 2021 13:29:17 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Maxime Chevallier <maxime.chevallier@bootlin.com>
Cc:     Shawn Guo <shawnguo@kernel.org>, Rob Herring <robh+dt@kernel.org>,
        Andrew Lunn <andrew@lunn.ch>, thomas.petazzoni@bootlin.com,
        herve.codina@bootlin.com, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] ARM: dts: imx6qdl-sr-som: Increase the PHY reset
 duration to 10ms
Message-ID: <20210625122917.GW22278@shell.armlinux.org.uk>
References: <20210625121353.3698240-1-maxime.chevallier@bootlin.com>
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Sender: Russell King (Oracle) <linux@armlinux.org.uk>
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On Fri, Jun 25, 2021 at 02:13:53PM +0200, Maxime Chevallier wrote:
> The AR803x PHY used on this modules seems to require the reset line to
> be asserted for around 10ms in order to avoid rare cases where the PHY
> gets stuck in an incoherent state that prevents it to function
> correctly.
> 
> The previous value of 2ms was found to be problematic on some setups,
> causing intermittent issues where the PHY would be unresponsive
> every once in a while on some sytems, with a low occurrence (it typically
> took around 30 consecutive reboots to encounter the issue).
> 
> Bumping the delay to the 10ms makes the issue dissapear, with more than
> 2500 consecutive reboots performed without the issue showing-up.
> 
> Fixes: 208d7baf8085 ("ARM: imx: initial SolidRun HummingBoard support")
> Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
> Tested-by: Herv? Codina <herve.codina@bootlin.com>

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

Thanks!

-- 
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