cpufreq support on Allwinner H3

[Luc Hondareyte]

Le 08/03/2018 à 06:18, Emmanuel Vadot a écrit :
> On Tue, 6 Mar 2018 20:59:37 +0100
> Luc Hondareyte via freebsd-arm <freebsd-arm at freebsd.org> wrote:
>
>> Hi,
>>
>> I've just build 12-current for Allwinner H3  (armv7) and it seems that
>> cpufreq support is missing (orangepi or nanopi):
>   There is no opp table (freq<->voltage table) in the DTS that's why
> it's not working.
This thread? 
http://lists.infradead.org/pipermail/linux-arm-kernel/2018-February/557940.html 

>   I think I've seen patches on the linux-arm kernel mailing list to add
> them but even with thoses we will need support for the v2 opp.
v2 opp? Does it mean that, as a workaround, with the appropriate DTS 
patch and a switch back to armv6, this should work? I say that because, 
on nanopi neo, with the "old" 12-current image build by Ganbold 
Tsagaankhuu (that was available on FriendlyArm Wiki), cpu_freq support 
is OK and it’s run at full speed:

root at allwinner-h3:~ # uname -a
FreeBSD allwinner-h3 12.0-CURRENT FreeBSD 12.0-CURRENT #7 r308116M: Mon 
Oct 31 10:56:20 ULAT 2016 
tsgan at beastie.mstride.com:/usr/obj/arm.armv6/usr/src/sys/GENERIC arm
root at allwinner-h3:~ # sysctl dev.cpu.0.freq
cpufreq: get returning known freq 1008
cpufreq: get returning known freq 1008
dev.cpu.0.freq: 1008

And this image does not seem to use Linux DTS.
>> root at allwinner-h3:~ # service powerd onestart
>> Starting powerd.
>> powerd: no cpufreq(4) support -- aborting: No such file or directory
>> /etc/rc.d/powerd: WARNING: failed to start powerd
>>
>> So, on nanopi neo, it's slowdown (not on orange-pi that seems to run at
>> full speed). I am using a custom kernel conf that just contains:
>>
>> include GENERIC
>> nooptions       INVARIANTS
>> nooptions       INVARIANT_SUPPORT
>> nooptions       WITNESS
>> nooptions       WITNESS_SKIPSPIN
>> nooptions       BUF_TRACKING
>> nooptions       DEADLKRES
>> nooptions       FULL_BUF_TRACKING
>>
>   You can use the GENERIC-NODEBUG for that
>
Oh, I missed that. Thanks.