Re: [PATCH 1/4] arm64: dts: rockchip: list all CPU supplies on ArmSoM Sige5

Piotr Oniszczuk
2025-06-08T07:24:24Z

> Wiadomość napisana przez Alexey Charkov <alchark@gmail.com> w dniu 5 cze 2025, o godz. 15:42:
>>
>>>
>>>
>>
>> Alexey,
>> I see you are using rk3576 board like me (nanopi-m5)
>> Have you on your board correctly working cpu dvfs?
>> I mean: [1][desired clocks reported by kernel sysfs are in pair with [2[]cur clocks?
>> In my case i see mine cpu lives totally on it’s own with dvfs:
>
> Hi Piotr,
>
> I haven't tried to validate actual running frequencies vs. requested
> frequencies, but subjective performance and power consumption seem to
> be in line with what I expect.

well - my subjective l&f is that - currently - my rk3576 seems „slower" than i.e. 4xA53 h618.
This directed me to investigate this issue.
Test run was media player (mythtv) where ui has gl effects and ui gl transitions „speed” are quite proportional to cpu speed (and gpu).
My overall feeling is: ux is comparable to slow socs 4xA53@1.4GHz/G31. This is with mainline atf + collabora uboot [1] and on-demand gov.
I done test with replacing uboot from mainline atf + collabora uboot to bin. dump of vendor uboot (2017.09) and with this ux become almost as expected (i mean comparable with i.e. rk3399).

I done test with perf gov. and

1.collabora uboot[1] + mainline atf 2.13
2.collabora uboot[1] + rockchip rkbin bl31 blob [2]
3.vendor uboot (bin dump from friendlyelec ubuntu image)

[a] on vendor uboot:
Requested CPU4: 2304 MHz
Requested CPU0: 2208 MHz
Running CPU4: 1008 MHz
Running CPU0: 1008 MHz
Measured on HW: 1580.11 MHz

[b] on collabora uboot + mainline atf:
Requested CPU4: 2304 MHz
Requested CPU0: 2208 MHz
Running CPU4: 816 MHz
Running CPU0: 816 MHz
Measured on HW: 808.72 MHz

[c] on collabora uboot + rockchip rkbin bl31 blob:
Requested CPU4: 2304 MHz
Requested CPU0: 2208 MHz
Running CPU4: 816 MHz
Running CPU0: 816 MHz
Measured on HW: 812.49 MHz

in all cases all clocks are constant as they should
Interesting that on collabora uboot [b][c] measured clock is 808 vs 1580 on vendor uboot [a]...
sw video decode conforms this diff: hd h264 gets cpu load: 172%[b][c] vs 87%[a]

….

>
>
> Are these taken on the mainline kernel or Rockchip one?

I tested:

6.15 mainline + some collabora patches

1.collabora uboot[1] + mainline atf 2.13
2.collabora uboot[1] + rockchip rkbin bl31 blob [2]
3.vendor uboot (bin dump from friendlyelec ubuntu image)

> Binary BL31
> from Rockchip or opensource TF-A? With big-core CPUs linked up to
> their supply regulator (as per this patch)

yes

So summarising:

1. i see kind of issue with clock values (e.g. perf gov gives 800MHz on mainline atf).
imho rot cause seems to be in collabora uboot

2. on-demand gov. seems behave much more like powersave.
this seems to be 3576 specific:
-on 3588 change from perf to on_demand is hardly noticeable in ux
-on 3576 such change makes ux feeling noticeable slow (like 4xA53 soc)
i think this is more related to diff between scmi mcu gov algo in 3576 vs. 3588
(imho 3576 algo has high latency in clock increases when demand happens + too short delay for clocks decreases to save power)

[1] https://gitlab.collabora.com/hardware-enablement/rockchip-3588/u-boot
[2] https://github.com/rockchip-linux/rkbin/blob/master/bin/rk35/rk3576_bl31_v1.15.elf