We are trying to achieve the <image_name>.rootfs.wic + bootloader of the size that able to flash and boot from SPI NOR flash of 32MB.
We have a 32MB SPI NOR flash memory on our custom board based on imx8qxp MEK. For verification and testing, we are using an imx8qxp board with 64MB of SPI NOR flash. We are using the Yocto Zeus, L5.4.24-2.1.0.
The x-wayland distro and core-image-minimal is used which gives <image_name>.rootfs.wic.bz2 of size 32.5MB.
We require a very minimal system so we tried to use poky or poky-tiny but as it is not supported by the i.MX 8 or i.MX 8M. So we remove the distro feature using the DISTRO_FEATURES_remove variable in local.conf. After removing the unwanted distro feature using the that gives an image size of 31.3MB (distro features removed: Bluetooth, wifi,ipv4, ipv6, largefile, nfs, etc.)
The next step followed was to configure the kernel using Creating a defconfig File(Yocto Project Linux Kernel Development Manual) and removed the network support and unused driver's support but there is no size reduction achieved.
Also you can decrease kernel size by removing "inline" option of many functions. However it may decrease the performance as well. So please do it with an accuracy.
