Re: [RFC-next 0/1] Odroid C2: Enable DVFS for cpu

[Kevin Hilman]

Anand Moon <linux.amoon@xxxxxxxxx> writes:

> Hi Neil / Kevin,
>
> On Tue, 10 Dec 2019 at 14:13, Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>>
>> On 09/12/2019 23:12, Kevin Hilman wrote:
>> > Anand Moon <linux.amoon@xxxxxxxxx> writes:
>> >
>> >> Some how this patch got lost, so resend this again.
>> >>
>> >> [0] https://patchwork.kernel.org/patch/11136545/
>> >>
>> >> This patch enable DVFS on GXBB Odroid C2.
>> >>
>> >> DVFS has been tested by running the arm64 cpuburn
>> >> [1] https://github.com/ssvb/cpuburn-arm/blob/master/cpuburn-a53.S
>> >> PM-QA testing
>> >> [2] https://git.linaro.org/power/pm-qa.git [cpufreq testcase]
>> >>
>> >> Tested on latest U-Boot 2019.07-1 (Aug 01 2019 - 23:58:01 +0000) Arch Linux ARM
>> >
>> > Have you tested with the Harkernel u-boot?
>> >
>> > Last I remember, enabling CPUfreq will cause system hangs with the
>> > Hardkernel u-boot because of improperly enabled frequencies, so I'm not
>> > terribly inclined to merge this patch.
>
> HK u-boot have many issue with loading the kernel, with load address
> *it's really hard to build the kernel for HK u-boot*,
> to get the configuration correctly.
>
> Well I have tested with mainline u-boot with latest ATF .
> I would prefer mainline u-boot for all the Amlogic SBC, since
> they sync with latest driver changes.

Yes, we would all prefer mainline u-boot, but the mainline kernel needs
to support the vendor u-boot that is shipping with the boards.  So
until Hardkernel (and other vendors) switch to mainline u-boot we do not
want to have upstream kernel defaults that will not boot with the vendor
u-boot.

We can always support these features, but they just cannot be enabled
by default.

Kevin