Subject: Re: [PATCH spi for-5.4 0/5] Deterministic SPI latency with NXP DSPI driver

From: Richard Cochran <[email-masked]>
Date: Thu, 22 Aug 2019 22:22:17 -0700

On Thu, Aug 22, 2019 at 07:13:12PM +0300, Vladimir Oltean wrote:
> You do think that I understand the problem? But I don't!

;^)

> > And who generates Local_sync_resp?
> >
> 
> Local_sync_resp is the same as Local_sync_req except maybe with a
> custom tag added by the switch. Irrelevant as long as the DSA master
> can timestamp it.

So this is point why it won't work.  The time stamping logic in the
switch only recognizes PTP frames.
 
Thanks,
Richard