Comparing various bootloaders

As we read earlier, a number of bootloaders are available for embedded systems. The ones that will be presented here are as follows:

• U-Boot: This is also called the Universal Bootloader and is available mostly for PowerPC and ARM architectures for embedded Linux systems
• Barebox: This was initially known as U-Boot v2 and was started in 2007 with the scope to solve the limitations of U-Boot; it changed its name over time because the design goals and community changed
• RedBoot: This is a RedHat bootloader derived from eCos, an open-source real-time operating system that is portable and devised for embedded systems
• rrload: This is a bootloader for ARM and is based on embedded Linux systems
• PPCBOOT: This is a bootloader for PowerPC and is based on embedded Linux systems
• CLR/OHH: This represents a flash bootloader for embedded Linux systems based on an ARM architecture
• Alios: This is a bootloader that is written mostly in assembler, does ROM and RAM initializations, and tries to completely remove the need for firmware on embedded systems

There are a number of bootloaders available and this is a natural outcome of the fact that there are a huge number of different architectures and devices, so many, in fact, that it is almost near impossible to have one that would be good for all systems. The variety of bootloaders is high; the differentiator factors are represented by the board types and structure, SOC differences and even CPUs.