Re: [PATCH net-next v1 13/14] net: phy: nxp-c45-tja11xx: reset PCS if the link goes down

From: Andrew Lunn
Date: Fri Jun 16 2023 - 17:00:37 EST


On Fri, Jun 16, 2023 at 04:53:22PM +0300, Radu Pirea (NXP OSS) wrote:
> During PTP testing on early TJA1120 engineering samples I observed that
> if the link is lost and recovered, the tx timestamps will be randomly
> lost. To avoid this HW issue, the PCS should be reseted.
>
> Resetting the PCS will break the link and we should reset the PCS on
> LINK UP -> LINK DOWN transition, otherwise we will trigger and infinite
> loop of LINK UP -> LINK DOWN events.

> +static int tja1120_read_status(struct phy_device *phydev)
> +{
> + unsigned int link = phydev->link;
> + int ret;

Maybe consider using link_change_notify:

/**
* @link_change_notify: Called to inform a PHY device driver
* when the core is about to change the link state. This
* callback is supposed to be used as fixup hook for drivers
* that need to take action when the link state
* changes. Drivers are by no means allowed to mess with the
* PHY device structure in their implementations.
*/
void (*link_change_notify)(struct phy_device *dev);

Seems like a fixup to me.

Andrew