Undervolted kernel

[weter11]

Hi! I'm searching for kernel that can reduce overheating problems on a phone, LG G4 & N5X already has such feature as undervolting, but no any kernels for Mi4c that has it.
Thanks for any answer, maybe tutorial how to do that or link on github.

 

[andrei80]

No such thing yet for Mi4C, I'm afraid...I've searched for that too, and found nothing. Kernel was released in may 2016 for this phone and there are good stable roms, but no undervolting yet, just big cores disable/throttle management solutions.

 

[weter11]

Ok. Now I have that thing as display voltages via sysfs. It wasn't too hard to implement. But it only display that, no any changes if I trying change any values.
Also for geeks. Some screens with Geekbench when phone not throttling frequencies. It was hard (Environment temperature was 2°C, phone was on cooler).
Sorry can't upload screenshot (rules about 10 posts).
So power was 6W (I think 1W for 4xA53 (values from Anandtech), 0.5W for system and yeah 4.5W for only 2xA57). I don't undestand why so many.
Voltage table A53&A57
384mhz: 800 mV 460mhz: 865 mV 600mhz: 865 mV
672mhz: 885 mV 787mhz: 915 mV 864mhz: 945 mV
960mhz: 975 mV 1248mhz: 1070 mV 1440mhz: 1130 mV
384mhz: 890 mV 480mhz: 890 mV 633mhz: 890 mV
768mhz: 910 mV 864mhz: 920 mV 960mhz: 930 mV
1248mhz: 985 mV 1344mhz: 1005 mV 1440mhz: 1020 mV
1536mhz: 1040 mV 1632mhz: 1055 mV 1689mhz: 1070 mV
1824mhz: 1090 mV

 

[Sakura_Sa233]

I just closed down the cpu core to solve it

 

[weter11]

Ok, finally I compile that. Results are impressive. So A53 UV up to 0.97V, A57 up to 0.93V(at max frequencies). Geekbench and GFXbench phone pass. No any stutter. At lower voltages receive boot loop. Sorry if someone want to test, I don't have 10 posts yet to include external links. No more needed underclock CPU.
Also now I have another problem, in some games main overheating come from GPU(own power from GPU=4W). I searching how UV it, but w/o luck. If someone can help links or some other stuff.

 

[coroneta]

Ok, finally I compile that. Results are impressive. So A53 UV up to 0.97V, A57 up to 0.93V(at max frequencies). Geekbench and GFXbench phone pass. No any stutter. At lower voltages receive boot loop. Sorry if someone want to test, I don't have 10 posts yet to include external links. No more needed underclock CPU.
Also now I have another problem, in some games main overheating come from GPU(own power from GPU=4W). I searching how UV it, but w/o luck. If someone can help links or some other stuff.

Give me the link by pm and i will post it!!

 

[coroneta]

Ok here is the link!
can you explain how to use this mod?,thanks!

https://mega.nz/#!UQFCCZ7D!j3q1vAeJiit5h0zkkHMMWWApkXKXN4u9TW_FRJBwpN4

 

[weter11]

So, I prefer install in 3 steps
1. Unzip image: /storage/emulated/0/uvv.img (home folder);
2. Reboot to TWRP - Intall - Install image - Select uvv.img - Install to boot.
3. Reboot.
Kernel support all modern features: F2FS, NTFS, EXFAT, different CPU, GPU, IO governors, LiveDisplay, KCAL.
Also minimum CPU frequency 302 MHz.
Frequency/voltage table can displayed by any kernel manager, that support this feature or manually /sys/devices/system/cpu/cpu0/cpufreq/UV_mv_table.

 

[adamuadamu]

Ok here is the link!
can you explain how to use this mod?,thanks!

https://mega.nz/#!UQFCCZ7D!j3q1vAeJiit5h0zkkHMMWWApkXKXN4u9TW_FRJBwpN4

I get only a .dtsi file from download, what am I supposed to do with it?

 

[weter11]

Sorry. This is the main file, that contain voltages, if someone want to know.
I'll send a new PM with kernel.

 

[coroneta]

Here is the link with kernel

https://mega.nz/#!4csihbDZ!eUrWnOaYPtmgxor8TAMyLlnsAFJ8GiXKTtV-C9zSUak

 

[solis_f]

Here is the link with kernel

https://mega.nz/#!4csihbDZ!eUrWnOaYPtmgxor8TAMyLlnsAFJ8GiXKTtV-C9zSUak

Used this on miui and got bootloop

 

[adamuadamu]

tried with CM13.1 by TS and didn't get past MI bootlogo. flashed via flashify

 

[solis_f]

Sorry. This is the main file, that contain voltages, if someone want to know.
I'll send a new PM with kernel.

For what roms does it work?

 

[weter11]

Its compatible with latest CM14.1. About other systems don't know. That needed another kernels as I can see now.

 

[weter11]

CM14.1 wokrs really good. Its have only one bug: it isn't themes manager at this moment, but interface much smoother than it was in 13.1. All features, that work in 13.1 also work in 14.1.
About Miui, don't know is it possible using custom kernels on Miui.

 

[adamuadamu]

Its compatible with latest CM14.1.

a request if I may ask: could you possibly compile a kernel for cm13? I'd like to try it, but as long as xposed is no-go for nougat, I won't switch to CM14 (national roaming is a must for me)

 

[weter11]

Ok. I understand. I'll try to compile it. Link to kernel for your CM 13.1 on github please or CM13.1 compatible with your ROM kernel.

 

[Cozzmy13]

Ok. I understand. I'll try to compile it. Link to kernel for your CM 13.1 on github please or CM13.1 compatible with your ROM kernel.

https://github.com/kumajaya/android_kernel_xiaomi_msm8992

If you don't have time I can do it too, I already compiled this kernel.

 

[weter11]

Cozzmy13, of cource. File, that is needed to upgrade is on page 1. But if you want see voltages, there another two files to change. If interesting, tomorrow I'll write that.