Re: [PATCH 2/2] net: phy: realtek: add support for configuring the RX delay on RTL8211F

Florian Fainelli
2019-12-26T20:55:27Z

On 12/26/2019 10:51 AM, Martin Blumenstingl wrote:
> On RTL8211F the RX and TX delays (2ns) can be configured in two ways:
> - pin strapping (RXD1 for the TX delay and RXD0 for the RX delay, LOW
> means "off" and HIGH means "on") which is read during PHY reset
> - using software to configure the TX and RX delay registers
>
> So far only the configuration using pin strapping has been supported.
> Add support for enabling or disabling the RGMII RX delay based on the
> phy-mode to be able to get the RX delay into a known state. This is
> important because the RX delay has to be coordinated between the PHY,
> MAC and the PCB design (trace length). With an invalid RX delay applied
> (for example if both PHY and MAC add a 2ns RX delay) Ethernet may not
> work at all.
>
> Also add debug logging when configuring the RX delay (just like the TX
> delay) because this is a common source of problems.
>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

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