STEP 3: Execute the below character to list out all the partition’s. ( Note:As my device showing as /dev/sdc, I’ll refer /dev/sdc instead of /dev/sdX) Note:- it will show something like below location. Insert the formated microSD Card into your computer and observe which device it registers as by typing command: kernel.img, is the first! thing that runs on the ARM processor.We will use u-boot as kernel.img so our config.txt will look as:Īfter completing above steps Booting is completed and RPI board is ready to take a commands from user. We will use config.txt to tell start.elf to load the kernel.img image. It starts by reading config.txt, a text file containing configuration parameters for both the VideoCore (Video/HDMI modes, memory, console frame buffers etc) and loading of the Linux Kernel (load addresses, device tree, uart/console baud rates etc). The third stage bootloader – start.elf – is where all the action happens. (Historically, yet another bootloader called loader.bin was loaded at this stage, but has since been phased out)

The second stage bootloader – bootcode.bin – is executed on the VideoCore GPU and loads the third stage bootloader – start.elf. The first stage bootloader is designed to load the second stage bootloader (bootcode.bin) from a FAT32 or FAT16 file system on the SD Card. It loads the first stage boot oader from a ROM embedded within the SoC.

The VideoCore IV GPU core is responsible for booting the system. The Raspberry Pi’s Broadcom BCM2835 system on a chip (SoC) powers up with its ARM1176JZF-S 700 MHz processor held in reset. (The Raspberry PI Compute Module has 4GB eMMC Flash on-board). Rather, a SD/MMC card slot is provided for this purpose. To reduce cost, the Raspberry Pi (Model A & B) omits any on-board non-volatile memory used to store the boot loaders, Linux Kernels and file systems as seen in more traditional embedded systems.

This article is a quick start up guide on porting U-Boot for Raspberry-PI board using SD card. The U-Boot utility is a multi-platform, open-source, universal boot-loader with comprehensive support for loading and managing boot images, such as the Linux kernel.

More than 1 boot.elf