Android Customizing the Linux kernel: Difference between revisions

Latest revision as of 21:59, 12 September 2023

VAR-SOM-MX6 - N7.1.1 - Customizing the Linux kernel

Making changes to kernel configuration

$ cd ~/var_n_711_100/n_711_100_build/vendor/variscite/kernel_imx/
$ make ARCH=arm mrproper
$ make ARCH=arm imx_v7_var_android_defconfig
$ make ARCH=arm menuconfig

Navigate through the menu, and select the desired kernel functionalities, save the new configuration, and exit.
Then, save the new configuration as the default configuration:

$ make ARCH=arm savedefconfig
$ cp arch/arm/configs/imx_v7_var_android_defconfig arch/arm/configs/imx_v7_var_android_defconfig.orig 
$ cp defconfig arch/arm/configs/imx_v7_var_android_defconfig

Making changes to the device tree

For example, edit the following file:

VAR-SOM-MX6 : ~/var_n_711_100/n_711_100_build/vendor/variscite/kernel_imx/arch/arm/boot/dts/imx6qdl-var-som.dtsi
DART-MX6: ~/var_n_711_100/n_711_100_build/vendor/variscite/kernel_imx/arch/arm/boot/dts/imx6qdl-var-dart.dtsi

For example, if you want to make changes related to the SPI configuration you can refer to: SPI

Build a new boot.img

When you perform changes to the kernel, you may build boot.img solely instead of building the whole Android.

$ cd ~/var_n_711_100/n_711_100_build
$ source build/envsetup.sh
$ lunch -userdebug
$ make bootimage

Flashing the boot image to the target

Run the following to boot the device into fastboot mode and reflash the boot image:

$ adb reboot bootloader
$ sudo `which fastboot` flash bootout/target/product/var_mx6/boot-<setup-name>.img
Replace setup-name as per above table.
$ sudo `which fastboot` reboot

@@ Line 2: / Line 2: @@
 --> {{#vardefine:RELEASE_PARAM|{{#urlget:release}}}} <!--
 --> {{#lst:Android_Platform_Customization|{{#var:RELEASE_PARAM|RELEASE_N7.1.1_1.0.0_VAR-SOM-MX6}}}} <!--
---> {{PageHeader|{{#var:HARDWARE_NAME}} - Android {{#var:ANDROID_NAME}} {{#var:ANDROID_VERSION}} - Customizing the Linux kernel}} {{DocImage|category1={{#var:HARDWARE_NAME}}|category2=Android}} __toc__
+--> {{PageHeader|{{#var:HARDWARE_NAME}} - {{#var:ANDROID_VERSION}} - Customizing the Linux kernel}} {{DocImage|category1=Android|category2={{#var:HARDWARE_NAME}}}} __toc__
 == Making changes to kernel configuration ==
@@ Line 9: / Line 9: @@
   $ make ARCH={{#ifeq: {{#var:HARDWARE_NAME}} |VAR-SOM-MX6|arm|arm64}} {{#var:KERNEL_DEFCONFIG}}
   $ make ARCH={{#ifeq: {{#var:HARDWARE_NAME}} |VAR-SOM-MX6|arm|arm64}} menuconfig
-Navigate the menu and select the desired kernel functionalities, save the new configuration and exit.<br>
+Navigate through the menu, and select the desired kernel functionalities, save the new configuration, and exit.<br>
 Then, save the new configuration as the default configuration:<br>
   $ make ARCH={{#ifeq: {{#var:HARDWARE_NAME}} |VAR-SOM-MX6|arm|arm64}} savedefconfig
   $ cp arch/{{#ifeq: {{#var:HARDWARE_NAME}} |VAR-SOM-MX6|arm|arm64}}/configs/{{#var:KERNEL_DEFCONFIG}} arch/{{#ifeq: {{#var:HARDWARE_NAME}} |VAR-SOM-MX6|arm|arm64}}/configs/{{#var:KERNEL_DEFCONFIG}}.orig
-  $ cp defconfig arch/{{#ifeq: {{#var:HARDWARE_NAME}} |VAR-SOM-MX6|arm|arm64}}/configs/
+  $ cp defconfig arch/{{#ifeq: {{#var:HARDWARE_NAME}} |VAR-SOM-MX6|arm|arm64}}/configs/{{#var:KERNEL_DEFCONFIG}}
 == Making changes to the device tree ==
@@ Line 25: / Line 25: @@
   $ source build/envsetup.sh
   $ lunch {{#var:ANDROID_MACHINE_NAME}}-userdebug
+ {{#ifeq: {{#var:HARDWARE_NAME}} | VAR-SOM-MX6 |
+ $ make bootimage
+ |
   $ make bootimage
+ $ make dtboimage
+ }}
 == Flashing the boot image to the target ==
 Run the following to boot the device into fastboot mode and reflash the boot image:<br>
   $ adb reboot bootloader
-  $ sudo `which fastboot` flash boot{{#ifeq: {{#var:HARDWARE_NAME}} | VAR-SOM-MX6 | out/target/product/var_mx6/boot-<setup-name>.img |_a out/target/product/out/target/product/{{#var:ANDROID_MACHINE_NAME}}/boot.img }}
+  $ sudo `which fastboot` flash boot{{#ifeq: {{#var:HARDWARE_NAME}} | VAR-SOM-MX6 | out/target/product/var_mx6/boot-<setup-name>.img |_a out/target/product/{{#var:ANDROID_MACHINE_NAME}}/boot.img }}
   {{#ifeq: {{#var:HARDWARE_NAME}} | VAR-SOM-MX6 |
@@ Line 41: / Line 46: @@
   $ sudo `which fastboot` reboot
 {{#ifeq: {{#var:HARDWARE_NAME}} | VAR-SOM-MX6 ||
-Note: While flashing if you encouter like below <br>
+*Note: While flashing if you encouter like below <br>
   $ sudo `which fastboot` flash boot_a out/target/product/{{#var:ANDROID_MACHINE_NAME}}/boot.img <br>
   target reported max download size of 1073741824 bytes
@@ Line 50: / Line 55: @@
   Finished. Total time: 1.772s
 Make sure you unlock your device following<br>
-{{Varlink|Fastboot Unlock|{{#var:RELEASE_LINK}}|Fastboot Unlock}}
+{{Varlink|Fastboot Unlock|{{#var:RELEASE_LINK}}|Fastboot Unlock}} and then follow the steps above
 }}