Re: [PATCH 1/2] net: phy: realtek: add logging for the RGMII TX delay configuration
From: Florian Fainelli
Date: Thu Dec 26 2019 - 15:54:48 EST
On 12/26/2019 10:51 AM, Martin Blumenstingl wrote:
> RGMII requires a delay of 2ns between the data and the clock signal.
> There are at least three ways this can happen. One possibility is by
> having the PHY generate this delay.
> This is a common source for problems (for example with slow TX speeds or
> packet loss when sending data). The TX delay configuration of the
> RTL8211F PHY can be set either by pin-strappping the RXD1 pin (HIGH
> means enabled, LOW means disabled) or through configuring a paged
> register. The setting from the RXD1 pin is also reflected in the
> register.
>
> Add debug logging to the TX delay configuration on RTL8211F so it's
> easier to spot these issues (for example if the TX delay is enabled for
> both, the RTL8211F PHY and the MAC).
> This is especially helpful because there is no public datasheet for the
> RTL8211F PHY available with all the RX/TX delay specifics.
>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
--
Florian