[EXT] Re: [PATCH v2 net 2/2] net: stmmac: dwmac-imx: pause the TXC clock in fixed-link

[Shenwei Wang]

> -----Original Message-----
> From: Andrew Lunn <andrew at lunn.ch>
> Sent: Friday, July 28, 2023 11:56 AM
> To: Shenwei Wang <shenwei.wang at nxp.com>
> Cc: Fabio Estevam <festevam at gmail.com>; Russell King
> <linux at armlinux.org.uk>; David S. Miller <davem at davemloft.net>; Eric
> Dumazet <edumazet at google.com>; Jakub Kicinski <kuba at kernel.org>; Paolo
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> Subject: Re: [EXT] Re: [PATCH v2 net 2/2] net: stmmac: dwmac-imx: pause the
> TXC clock in fixed-link
> 
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> 
> > > Andrew Lunn gave the following feedback in v1:
> > >
> > > "The SJA1105 has the problem, so i would expect it to be involved in the
> solution.
> > > Otherwise, how is this going to work for other MAC drivers?
> > >
> > > Maybe you need to expose a common clock framework clock for the TXC
> > > clock line, which the SJA1105 can disable/enable? That then makes it
> > > clear what other MAC drivers need to do."
> >
> > I have been considering this plan for some time. The idea should be
> > implemented across all i.mx8/9 platforms. I am going to start to work
> > on it in the following month, and it will take some time to implement it.
> 
> So you don't think anybody will use anything else for driving this switch? Vybrid?
> 

Vybrid or i.MX6 don't have such kind of problem because they are not using dwmac.
Those are FEC MACs, and the MAC itself can provide delay to the switch.

Thanks,
Shenwei

> It does not really matter what you implement it for, so long is at is a clear
> example for others to follow who might be using the switch with other SoCs.
> 
>         Andrew