Re: [PATCH mvebu v2 00/10] Armada 37xx: Fix cpufreq changing base CPU speed to 800 MHz from 1000 MHz

From: nnet
Date: Tue Feb 09 2021 - 21:21:24 EST


On Tue, Feb 9, 2021, at 3:26 PM, Marek Behún wrote:
> On Tue, 09 Feb 2021 15:16:45 -0800
> nnet <nnet@xxxxxxxxxxx> wrote:
>
> > I've two of these and I've just swapped them (and re-pasted the heat sinks).
> >
> > The second one ran under load for awhile and now has frozen as well.
> >
> > Under a moderate load `wget -O /dev/null <large.bin>` @X00Mbits they are fine.
> >
> > Under a 1 min speed test of load ~200Mbits routed WireGuard they freeze.
> >
> > They fine with both those workloads @1000_800.
> >
> > Perhaps it's heat? Unfortunately I don't have any numbers on that ATM.
>
> Try disabling cpufreq in kernel completely, compile boot image at
> 1200 MHz. If it continues freezing, then I fear we can't help you with
> 1200 MHz :(

cat /sys/devices/system/cpu/cpufreq/policy0/scaling_available_frequencies
200000 300000 600000 1200000

I'm not getting any freezes with 1.2GHz fixed after 20 minutes of load:

echo 1200000 > /sys/devices/system/cpu/cpufreq/policy0/scaling_min_freq

Setting it back to min 200MHz I get a freeze within a minute:

echo 200000 > /sys/devices/system/cpu/cpufreq/policy0/scaling_min_freq

> Marek
>