What is boot loader in embedded Linux?
In embedded systems the bootloader is a special piece of software whose main purpose is to load the kernel and hand over the control to it. To achieve this, it needs to initialize the required peripherals which helps the device to carry out its intended functionality.
What is the difference between startup code and bootloader?
In brief, the bootloader is a second software inside the same flash with the application. On the other hand, the startup code will run in any case, with or without the bootloader. So startup code will run before your code. Bootloader is an entirely different software from the application.
How to reduce boot time in embedded Linux?
As a recommendation, do not optimize things that reduce the ability to make measurements and hinder implementing further optimizations. We start then from the last stage of the boot process, by optimizing the user-space and application start-up, then reduce kernel boot-time. Finally optimize the boot-loader (s).
Is there a way to speed up the boot speed of Linux?
Therefore, if you want to speed up the boot of your Linux system, it is critical that you modify the default startup setting in the Grub bootloader so that your Linux boot speed isn’t too slow. Making changes to the Grub configuration file, however small, is dangerous.
Is there a way to speed up the boot time in Grub?
By default, it’s set to 5 seconds, and for most people, that’s enough time to wait. However, if you’re looking to speed up your boot time, changing this number is the most effective way to do it. To change the boot speed in the Grub bootloader, you’ll need to modify the configuration file.
How does Linux boot up on an ARM processor?
Before starting any optimizations let’s get a closer look at a typical Embedded Linux boot-up sequence on an ARM processor and analyze how time is spent on each stage :