Re: [PATCH net-next 2/2] net: ethernet: ti: am65-cpsw: Enable RX HW timestamp only for PTP packets

[Siddharth Vadapalli]

On Mon, Feb 19, 2024 at 12:59:55PM +0200, Roger Quadros wrote:
> Hi,
> 
> On 15/02/2024 13:09, Chintan Vankar wrote:
> > The CPSW peripherals on J7AHP, J7VCL, J7AEP, J7ES, AM64 SoCs have
> > an errata i2401 "CPSW: Host Timestamps Cause CPSW Port to Lock up".
> 
..

> >  
> > @@ -856,6 +852,9 @@ static int am65_cpsw_nuss_rx_packets(struct am65_cpsw_common *common,
> >  		ndev_priv = netdev_priv(ndev);
> >  		am65_cpsw_nuss_set_offload_fwd_mark(skb, ndev_priv->offload_fwd_mark);
> >  		skb_put(skb, pkt_len);
> > +		skb_reset_mac_header(skb);
> 
> Why do you need to add skb_reset_mac_header here?
> 
> > +		if (port->rx_ts_enabled)
> > +			am65_cpts_rx_timestamp(common->cpts, skb);
> 
> The timestamp should be added before you do skb_put().

Roger,

Could you please clarify why the timestamp should be added before
skb_put()?

Regards,
Siddharth.