[Sony Xperia 1 III] Freak07:
Kirisakura-Kernel for the Sony Xperia 1 III

Hello everyone,

To keep it short: Here is Kirisakura - Kernel for the Sony Xperia 1 III aka Sagami. Sagami is the internal codename for this years development platform of Sony Mark III devices. Please note this kernel is made to run only on Xperia 1 III.

I would appreciate if everybody that flashes the kernel, reads at least once through this opening post and the following ones.

Kirisakura - Kernel is designed to bring a handful of beneficial features to the device, while ensuring excellent performance and smoothness to get you safely through the day!

If you expect a custom kernel to magically improve your devices battery life manifold and this is your only priority then this might not be the right place for you.

However the kernel is built to keep battery life close to the same as you would experience the on stock kernel while being tuned to perform better in various UI related benchmarks. The same benches are used by google to verify and ensure UI smoothness on the Pixel devices.

There´s also a cpu-battery saver mode that cuts back the CPU max- freqs, but without the disadvantages like delayed notifications from built into the system user-space power-saving modes.

If that got your curious, I welcome you to continue reading if you´re still interested!

The kernel includes a lot of improvements and contributions from other developers as well. Without this kernel would not exist.

A big part of improvements originate from @arter97´s, @kdrag0n´s and @Sultanxda´s work. Many others contributed in some way or another to this kernel.

A big thanks to all of them at this place!

Now lets continue with a list of features in the next paragraph!

Main Features:

- Based on latest kernel sources from Sony for Android 12 and intended to be used on the latest Stock-Firmware

- compiled with Clang 14.0.7 and built with -O3 speed optimizations

- Linux-Stable-Upstream included to 5.4.202

- upstreamed CAF base for the Snapdragon 888 (qcoms internal codename "lahaina")

- CPU-Battery saver to be able to restrict max cpufreqs on the fly, without enabling powersaving modes that might cause missed notifications (more info here)

- include important fixes/improvements from kernel/common

- reduce power consumption during deep sleep

- remove logging while device is suspended

- add SSG-IO scheduler from samsung (less overhead, better tuned towards android)

- disable various debugging mechanisms for drivers which are not needed on a perf build (e.g. binder)

- disable selinux auditing (we don´t have to adress selinux denials running a stock rom)

- disable unnecessary CPU errata for our specific SoC

- implement LRNG (thanks @arter97, see arter kernel OP for more info )

- Flashing the kernel will keep root!

- Flashable via EXKM, FKM or TWRP (if available) on a rooted system!

EAS related features:

- Implement dynamic WALT-Window size depending on current FPS, collecting information about CPU-Load to provide more precise information for the scheduler

- EAS implementation patched up to latest CAF state

- updates from kernel/common

- scheduler updates from sd888/ 5.4 kernel

CPU related features:

- Power saving workingqueues enabled by default (toggleable in EXKM)

- Change various drivers (WLAN, MM, audio, charger, power, thermal, glink etc) to use power efficient workingqueues. This compliments EAS in general

- improvements to cpufreq/times/stats

- vdso32 patches as found on Google Pixel devices (brief documentation here) (CAF 5.4 default, keep for documentation)

- remove event debug logging

- disable broken irq detection, disable debugmon

- improve suspend/resume from audio driver (caf-upstream for audio-kernel)

- cpuidle: wake only cpus for which qos has changed (this allows cores to keep idle states better)

- disable debugging during sleep states as per qcom recommendation

- remove RTB logging to reduce overhead

- disable trace_printk as it shouldn´t be used on production/perf kernel builds

- enable suspend_skip_sync to save power during suspend/resume

- disable edac and coresight (following google on the pixel kernels)

- disable jtagv8 debugging as recommended by qcom for perf builds to avoid potential power, performance and memory penalty

- disable s2idle in favor of deep idle state -> improves deep sleep drain (google initially used 2idle for improved suspend/resume latency on pixel 3 and pixel 4, but disabled it on pixel 5. qcom followed suit for sd 888, but apparently didn´t see google reverting it on pixel 5. Other OEMs such as Xiaomi or OnePlus already disabled s2idle on their SD888 devices in favor of deep- read more about s2idle vs deep here)

GPU related features:

- GPU driver updated to latest CAF-State

- gpu/kgsl improvements from pixel 4/pixel 5 kernel

- add low_prio_worker thread for gpu driver (Improves performance when tearing down processes (eg, via LMK) and not blocking currently running UI from submitting work to the GPU

File System related features:

- upstream BFQ-MQ to latest state in linux-mainline and default to 128KB readahead

- improve memory allocations in kernfs

- ufs improvements from pixel 4/ pixel 5 kernel

- improve GC as to not interfere while user interaction is happening and prevent possible jitter or latency spikes

Network related features:

- Wireguard Support (Details)

- advanced TCP algorithms enabled

- use bbr as default TCP congestion algorithm (fasted algo according to this excellent research from @kdrag0n found here )

- improved networking drivers from caf-upstream (especially wifi)

- remove unnecessary wakelock from WLAN driver to reduce thousands of very short wakeups during a 7 hour deep sleep period

- improved bluetooth performance (¹, ²)

- Enable support for TTL spoofing

Memory related features:

- Speculative Page Faults left enabled (1. 2) (CAF 5.4 default, keep for documentation)

- Fix various memory leaks in different subsystems

- improved mm with patches from mainline

- patches from kernel/common

- improve memory allocations in various subsystems, video encode/decode, kernfs, cgroup

- Backport to enable CONFIG_HAVE_MOVE_PMD (see here) , thanks @arter97

- Backport to enable CONFIG_HAVE_MOVE_PUD (commit here) , thanks @arter97

- free more RAM by removing unused reserved memory regions

- mm: Micro-optimize PID map reads for arm64 (improves game performance, especially unity based games such as genshin impact)

- MGLRU added (info here and here

Security related features:

- Control-Flow-Integration (CFI) and Link-Time-Optimization (LTO) (CAF 5.4 default, keep for documentation)

- Use ThinLTO which was first used in the Pixel 4 XL Android R-Kernel instead of full LTO (CAF 5.4 default, keep for documentation)

- Shadow Call Stack (SCS) Security-Feature ( 5.4 default, keep for documentation)

- enable init_on_alloc for even more security, more information can be found in the commit message (CAF 5.4 default, keep for documentation)

Misc Features:

Wakelock Blocker:

- advanced wakelock blocker with the ability to block any wakelocks (dangerous, use with caution)

- please read [URL="https://arstechnica.com/gadgets/2018/08/p-is-for-power-how-google-tests-tracks-and-improves-android-battery-life/"]this for further info

- blocking a kernel wakelock should only be done in case of firmware incompatabilities (WiFi network at work (can´t be changed) causes deep sleep to not work on the phone.) That´s the only use case I see for this feature. The kernel does not features this to improve battery life!

Other features:

- clean up asus drivers and fix a few warnings in kernel log

- disable logging and debugging to make the kernel more lightweight in various places (includes binder, mm, vma, gpu, ipa etc)

- fix several coding issues detected by newer Clang-Toolchains

- enlarge dmesg size to ease debugging

Flashing Guide, Download and Changelog

Requirements:

- unlocked Bootloader

- USB-Debugging in developer options enabled

- latest adb and fastboot binaries

- working adb and fastboot environment

- magisk root

- a backup of stock boot.img or your magisk patched boot.img in case you want to go back to stock.

How to flash the Kernel:

1. Download the latest kernel.zip and make sure you have properly updated to the latest matching Firmware (check the feature list for the current firmware the source is based on). When there´s an OTA update for the Sony Xperia 1 III it takes Sony a while to release the source code for the new OS and me a while to build a new kernel. If you don´t want to face any issues, wait until I either release an updated kernel or give green light because there were no kernel changes.

If you want to be sure there are no issues, always make sure to run the firmware the kernel is built for!

If you feel adventurous and try in advance, make sure you have a backup ready!

2. Flash the kernel.zip via latest TWRP (if available), EXKM or FKM app and do a full reboot.

3. Reboot and profit.

DOWNLOAD:

Download is located always in this folder:

https://www.androidfilehost.com/?w=files&flid=331114

Or attached to the release post starting with Android 13 as AFH is currently not working correctly

Important: Read after Download

Please take a look at the second post after flashing the kernel!

Changelog:

Android 11

1.0.0 Initial Release

1.0.1 https://xdaforums.com/t/kernel-20-1...xperia-1-iii-aka-sagami.4377449/post-86140929

Android 12

2.0.0

https://xdaforums.com/t/kernel-23-1...xperia-1-iii-aka-sagami.4377449/post-87099723

Android 13

3.0.0 https://xdaforums.com/t/kernel-02-0...xperia-1-iii-aka-sagami.4377449/post-88048199

3.0.1 https://xdaforums.com/t/kernel-25-0...xperia-1-iii-aka-sagami.4377449/post-88404445

Donations:

Donations are not mandatory but very welcome if you want to support development or just buy me a coffee/tea :)

If you like my work: http://paypal.me/freak07

Credits:

Sony for the development device, giving me the opportunity to create this project!

@osm0sis for all his work, including the ak3 installer!

@tbalden for being the best HTC, Pixel, OnePlus and now Asus wingman!

@LeeDroid and @mwilky for their awesome roms and work I used on multiple devices!

@Captain_Throwback for all the mentoring and guidance!

@Eliminater74 for bringing me into the game and the Inspiration

@nathanchance for his upstream guidance and assistance

@RenderBroken for helping me out

@flar2 for all his work

@joshuous for all the help he provided to me in the past!

@arter97 for giving me advice

@kdrag0n for his help and advices!

@topjohnwu for magisk!

Source Code: https://github.com/freak07/Kirisakura_Sagami