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Date:   Sat, 25 Jun 2022 08:50:57 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Peter Geis <pgwipeout@gmail.com>
Cc:     Sebastian Reichel <sebastian.reichel@collabora.com>,
        Giuseppe Cavallaro <peppe.cavallaro@st.com>,
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Subject: Re: [PATCH 1/3] net: ethernet: stmmac: dwmac-rk: Disable delayline
 if it is invalid
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> The driver already sets the delays to 0 in case of the rgmii-id modes.
> 0 is disabled, even in this patch. The only thing this patch does is
> change the behavior when the delays are not set. If the rx delays
> should be 0, they should be defined as 0 in the device tree. There is
> rgmii-rxid for a reason as well, but if they are setting the rx delay
> to 0 with rgmii that implies this hardware is fundamentally broken.

Or the delay is implemented by longer tracks on the PCB. It happens
sometimes, but not very often.

	   Andrew