Re: [PATCH v7 0/5] clk: add driver for the SiFive FU740

[Zong Li]

On Mon, Mar 29, 2021 at 6:37 PM Andreas Schwab <schwab@xxxxxxxxxxxxxx> wrote:
>
> On Mär 29 2021, Zong Li wrote:
>
> > Yes, I could get the network problem by using the defconfig you
> > provided, the system hung up when executing 'ifconfig' immediately
> > after installing macb driver module, the network can work by only
> > reverting the commit 732374a0b440d9a79c8412f318a25cd37ba6f4e2. But the
> > network is fine by using the mainline's defconfig, this is a little
> > bit weird, I will check that and try to find the difference.
>
> My guess would be that it is an init dependency problem between the phy
> driver and the clock driver, which causes the clock to be enabled too
> late.
>

I found that the gemgxlpll was disabled immediately by power
management after macb driver install. The mainline's defconfig doesn't
enable CONFIG_PM, so the network is fine on it. The opensuse defconfig
enables CONFIG_PM, and the patch
732374a0b440d9a79c8412f318a25cd37ba6f4e2 added the enable/disable
callback functions, so the gemgxlpll PLL, I have no idea why power
management disable it, I would keep trace it.

By the way, I tried to disable CONFIG_PM on oenpsuse defconfig, the
system didn't hang anymore, on the contrary, I enable CONFIG_PM on
mainline's defconfig, I expect that the system would hang up as well,
unfortunately, I cannot boot successfully by just enabling CONFIG_PM
easily.


> Andreas.
>
> --
> Andreas Schwab, schwab@xxxxxxxxxxxxxx
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> "And now for something completely different."