Build The Kernel From Scratch : Easy To Build

Here, many are facing problems while creating a Kernel from Scratch. So, today we gonna explain how to build a kernel and what errors you can face while creating a Kernal and how to solve them and also thanks to my Friend (Akash) who helped me in this.

Requirements 

1. A Linux Environment (Probably 64-Bit)

2. Knowledge in Linux like how to use the command line.

Download The Source

1. Find your device kernel source for compiling and in my case, for example, I'm taking the sources from (here) for  Whyred - sdm660. You can also Pick these sources if having the same.

                                                

Make Folder kernel and git clone them 

After Downloading the sources create a folder name it as kernel and open terminal with the same directory and type - git clone https://github.com/xiaomi-sdm660/android_kernel_Xiaomi_sdm660 and it will start downloading the kernel sources. You can download different kernel sources also according to your device requirements.

 Download Toolchain

After downloading the sources we have to download the cross compiler or Toolchain in order to compile the kernel.

arm(32 bit) - from (here)

arm(64 bit) -  from (here)

After downloading the toolchain git clone them on the same directory

Compile the Kernel

                                                            

Compiling the kernel

                                    

After downloading the sources and toolchain, open terminal on the previously created folder (kernel) and type following command:

1. export CROSS_COMPILE=/*directory of arm(64 bit) toolchain*/bin/aarch64-linux-android-

2. export CROSS_COMPILE_ARM32=/*directory of arm(64 bit) toolchain*/bin/arm-eabi-

3. make clean && make mrproper (this cleans all previously configured files)

4. export ARCH=arm64 && export SUBARCH=arm64 (The Architecture of whyred is 64-bit. If yours is 32-bit processor then you need to type arm32)

5. make whyred_defconfig

   Open your kernel source code folder go to "arch/arm/configs"

   Find that "yourdevicecode_defconfig"

   Ex- whyred_defconfig

6. make  -j# (replace # with your computer's CPU core count)

   Ex- make -j4

7. If those commands succeed, you will have an Image, Image-dtb, Image.gz, or Image.gz-dtb file at the end in (arch/arm64/boot)

8. While Compiling if any error comes, you may need to fix some headers or some other issues.

   ex- changing the #include <...> header to #include "..." for the error causing file.

 Using anykernel3 to zip the kernel image 

1. Download the latest AnyKernel3 - from (here) and extract it.

2. Place your kernel image in the root of the file.

3. Open the anykernel.sh file and modify the following values:

   @ kernel.string: your kernel name

   @ device.name#: List all of your device's codenames (from the /system/build.prop: ro.product.device, ro.build.product)

   @ block: Your boot image's path in your fstab. For whyred it is (block=/dev/block/bootdevice/by-name/boot;)

4. After that, zip up the kernel and flash it!

    Code:

          zip -r9 kernel.zip * -x README.md kernel.zip