[PATCH 1/2] net: fec_mxc: Fix clk_ref rate on iMX93

[Peng Fan]

> Subject: Re: [PATCH 1/2] net: fec_mxc: Fix clk_ref rate on iMX93
> 
> Hi Peng,
> 
> On Mon, Sep 23, 2024 at 10:11 AM Primoz Fiser
> <primoz.fiser at norik.com> wrote:
> 
> > Humm, but how did it work so far?
> >
> > On phyboard-segin-imx93, this change breaks fec ethernet.
> >
> > I had to revert this already in NXP downstream u-boot.
> 
> How does Linux handle this internal 1/2 divider?

Linux assigned-clock-rates set 250MHz, then internal divider
will set real clock to 125MHz.

> 
> Which board did you use to test this?
> 

I tested this on i.MX93-11x11-EVK.

> Since this causes a regression on phyboard-segin-imx93, we cannot
> apply it.

I will double check on this change. But I think this change
is required.

See fecmxc_set_ref_clk. Depending on the mode,
the freq will be different. I see segin using rmii mode, while
imx93evk use rgmii-id mode. This might be the difference.

Regards,
Peng.


Thanks,
Peng.

> 
> Please provide more details.