Re: [PATCH] clk: mxs: ensure that i.MX28's ref_io clks are not operated too fast

[Stefan Wahren <stefan.wahren@i2se.com>]

Hi,

> > On Thu, Jul 26, 2018 at 11:50 AM, Stefan Wahren <stefan.wahren@i2se.com=
> wrote:
> >=20
> > > I only want to note that we are using this ugly hack for Duckbill to =
avoid
> > > this issue:
> > >
> > > https://github.com/I2SE/linux/commit/e457d5e0309c07e30e8dd8b17c32f7b3=
cbdd9547
> >=20
> > Do you see the problem on TQMa28L with Stefan's hack applied?
>=20
> With this change by Stefan the bug is not reproducible. Your change to
> set the bypass bits only later doesn't help though.

i can confirm that Fabio's patch doesn't fix the clock issue on Duckbill. B=
ut the idea seems to be right. If i remove all write access to CLKSEQ and F=
RAC0 in clk_misc_init() instead of swap them, i don't need the ref_xtal hac=
k anymore. I think Fabio's patch doesn't work because the bootloader (U-Boo=
t in my case) is already feeding SSP from ref_io.

Regards
Stefan

>=20
> Best regards
> Uwe
>=20
> --=20
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