BeagleBone Black Ethernet PHY issues

[Geert Uytterhoeven]

Hi Robert,

On Wed, Oct 30, 2024 at 4:00 PM Robert Nelson <robertcnelson at gmail.com> wrote:
> On Tue, Oct 29, 2024 at 12:18 PM Geert Uytterhoeven
> <geert at linux-m68k.org> wrote:
> > During the last few months, booting kernels on BeagleBone Black
> > sometimes fails with:

> What revision of the board do you have, Bx, Cx, etc.

This particular one is a C3.

> Only C3 has the new PCB with the phy 'reset' gpio line.

Indeed.

> https://openbeagle.org/beagleboard/beaglebone-black/-/blob/master/BBB_SCH.pdf?ref_type=heads
>
> For pre-C3 boards, removing "C24" has fixed a large percentage of my
> boards in my ci test farm, while it's not a perfect fix as some still
> fail..

Yeah, C24 affects reset delay, too. But Rev. C3 does not have it
mounted.  My Rev. C (no known issues) should have it, and Rev. A5C
(the one that sometimes needs a manual reset after power-up) has only
1µF instead of 2.2µF.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds