[PATCH 2/2] net: phy: realtek: fix enabling of the TX-delay for RTL8211F

Florian Fainelli f.fainelli at gmail.com
Sat Nov 26 21:55:37 PST 2016

On 11/25/2016 05:12 AM, Martin Blumenstingl wrote:
> The old logic always enabled the TX-delay when the phy-mode was set to
> PHY_INTERFACE_MODE_RGMII. There are dedicated phy-modes which tell the
> PHY driver to enable the RX and/or TX delays:
> - PHY_INTERFACE_MODE_RGMII should disable the RX and TX delay in the
>   PHY (if required, the MAC should add the delays in this case)
> - PHY_INTERFACE_MODE_RGMII_ID should enable RX and TX delay in the PHY
> - PHY_INTERFACE_MODE_RGMII_TXID should enable the TX delay in the PHY
> - PHY_INTERFACE_MODE_RGMII_RXID should enable the RX delay in the PHY
>   (currently not supported by RTL8211F)
> With this patch we enable the TX delay for PHY_INTERFACE_MODE_RGMII_ID
> Additionally we now explicity disable the TX-delay, which seems to be
> enabled automatically after a hard-reset of the PHY (by triggering it's
> reset pin) to get a consistent state (as defined by the phy-mode).
> This fixes a compatibility problem with some SoCs where the TX-delay was
> also added by the MAC. With the TX-delay being applied twice the TX
> clock was off and TX traffic was broken or very slow (<10Mbit/s) on
> 1000Mbit/s links.
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl at googlemail.com>

Reviewed-by: Florian Fainelli <f.fainelli at gmail.com>

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