Re: [dpdk-dev] [PATCH v1 1/1] power: add support for cppc cpufreq

[Richael Zhuang <Richael.Zhuang@arm.com>]

> -----Original Message-----
> From: Burakov, Anatoly <anatoly.burakov@intel.com>
> Sent: Thursday, April 22, 2021 5:06 PM
> To: Richael Zhuang <Richael.Zhuang@arm.com>; dev@dpdk.org
> Cc: nd <nd@arm.com>; David Hunt <david.hunt@intel.com>
> Subject: Re: [dpdk-dev] [PATCH v1 1/1] power: add support for cppc cpufreq
> 
> On 22-Apr-21 7:15 AM, Richael Zhuang wrote:
> > Currently in DPDK only acpi_cpufreq and pstate_cpufreq drivers are
> > supported, which are both not available on arm64 platforms. Add
> > support for cppc_cpufreq driver which works on most arm64 platforms.
> >
> > Signed-off-by: Richael Zhuang <richael.zhuang@arm.com>
> > ---
> 
> Just a general note: this looks like a copy-paste of pstate code. Which is
> perfectly fine, except that we can do better than copying some faults of the
> pstate code to other drivers. I've submitted a patch [1] attempting to fix
> some of the pressing issues and code duplication in pstate driver, but i'm
> sure with a fresh driver, you can do even better :)
> 
> [1]
> http://patches.dpdk.org/project/dpdk/patch/20210402092701.258316-1-
> anatoly.burakov@intel.com/
> 
> --
> Thanks,
> Anatoly

For CPPC is defined in acpi v5.0+ spec,  I reused most code in acpi_cpufreq  to get a quick workable version on our platform with only cppc driver. I have verified  its basic functions. If you find some problems please help to point out thus I can rework it. Thanks .

Best Regards,
Richael