[Samsung Galaxy A21s ROMs, Kernels, Recoveries, & O] RiskyINIT:
Kawa Kernel A217X:

ABOUT:

KawaKernel is a performance oriented kernel tuned for pushing as much performance as possible from the device. The project was initially lead by Doz Naka but RiskyGUY22 (me) now leads it. This is the only regularly maintained kernel for the A217X and is of course the best choice for the A21s. Many changes have been made to optimize compiling time and to make your A21s as quick as physically possible, before it starts becoming dangerous. KernelSU is included in the Kernel meaning you will automatically have root privilege - the KernelSU version is constantly being updated in unison with the KSU Project.

Source Code:

- NEW Kawa Kernel Source

- OLD Kawa Kernel Source

Donations Link:

Any donations would be much appreciated and will inspire me to continue development.

- PayPal

Features:

Compiler

* Proton Clang compiler (Clang 13)

* Polly optimization flags

* Exynos 3830 optimization flags

Performance:

* NET: Default TCP Congestion Control: BBR + fq_codel qdisc

* NET: Enabled ECN negotiation by default

* NET: Improved network performance by using TCP_NODELAY

* MEM: Backported linux-5.17 lib/LZ4

* MEM: ZRam enabled with LZ4 as default compression algorithm

* MEM: KSM enabled (turned off by default)

* CPU: Overclocked to 2210 Mhz and underclocked to 130 Mhz

* CPU: Default CPUFREQ Governor: SCHEDUTIL

* GPU: Overclocked to 1196 Mhz and underclocked to 100 Mhz

* GPU: High speed frequency is 754 Mhz by default

* GPU: Adaptive power policy (default)

* GPU: Updated bitfrost drivers

Battery savings:

* Implemented Capacity Aware Superset Scheduler

* Implemented Powersuspend v2.0 driver

* Dynamic Fsync

* Kernelspace battery saver mode

* Samsung state notifier

Misc:

* Disabled SELinux audit logs

* Disabled Samsung Knox

* Disabled some of DEBUGFS

* Disabled some log spam

* Kernel support for Wireguard vpn

* Mass storage support (DriveDroid, etc)

* Prerooted with KernelSU

* Implemented SchedTune Assist

* CPU and GPU voltage control

* Stripped TWRP config

*And many more*

Installation Instructions:

1)

These instructions will assume that Kawa Kernel is being installed on the latest version of stock for any version of the A21s, although any Custom ROMs, GSIs and ports will work just fine. Flash Stock for your device and UNLOCK your bootloader, then enable developer options in settings by tapping on 'build number' a few times, then enabled USB debugging, which allows the phone to access your computer. There are many guides out there if you are struggling with this step.

If you already have Kawa Kernel installed and want to upgrade to a newer version if available

SKIP to step 7

2) Download vbmeta for your device, TWRP recovery, Odin, KawaKernel and ADB tools to somewhere appropriate on your computer.

- vbmeta(SA) / vbmeta(SB) First is for A217F SA Binary, Second is for A217M SB Binary

- TWRP

- ADB Tools

- Kawa Kernel

- Odin

3)

Now all of the files have been downloaded we can prepare your phone for installation!

- Power off your phone

- Plug your phone into a Computer and simultaneously hold the power up and power down buttons

- Once you reach a blue screen(Download mode) press the power up button to continue

- Open Odin and add your corresponding binary's vbmeta to the BL and USERDATA slot, keeping it as a tar achieve

- Add the recovery.tar file to AP and press Start. AS SOON AS THIS SUCCEEDS HOLD VOLUME UP AND POWER BUTTON

- It is fairly important that you don't let it boot into Stock, but instead your custom recovery

3 alternative linux method)

- Instead run the following commands in Download mode

sudo heimdall flash --VBMETA vbmeta.img

sudo heimdall flash --RECOVERY recovery.img

- Then reboot to recovery

4)

Now we are in TWRP Recovery we can install Kawa Kernel,

It is recommended to format data and disable FBE first as sometimes not doing this can cause issues,

Backup data if required

- Go to, Factory reset -> format data

- Advanced -> Reboot -> Recovery

- Advanced -> Terminal -> Type the following

multidisabler

- Advanced -> Reboot -> Recovery

- Advanced -> ADB sideload

5)

Now on your computer open up terminal and cd (change directory) to your adb tools/ROM folder. Then run the command replacing KERNEL_NAME with your corresponding Kernel name.

adb sideload KERNEL_NAME.zip

6)

Press 'Reboot System' and Download KernelSU for root access, enjoy!!!

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7)

So you already have Kawa Kernel installed and want to upgrade to the latest release,

From versions 2.9 and onward we can accomplish this using something called FCM,

It is a Kernel manager which allows for the use of OTA kernel updates,

First, Download the Kernel Manager and KernelSU if not already:

- Kernel Manager

- KernelSU

- Give the Kernel Manager root privilege through the KSU app

- In FKM press the the button with 3 lines and navigate to 'Flasher'

- Press Import a kernel download configuration and type the following **NOTE** this link will update automatically but may need to be re-entered into FCM between updates

For Enforcing:

https://raw.githubusercontent.com/samsungexynos850/KawaKernel-A217X/A12-stable/tools/OTA/kawa.json

For Permissive:

https://raw.githubusercontent.com/samsungexynos850/KawaKernel-A217X/A12-stable/tools/OTA/kawa-permissive.json

- Press FLASH and enjoy!

If you find any bugs or have any questions, don't hesitate to drop a comment and I will reply as quickly as I can.

Or post in the Telegram Group