Study on ARM9 – Linux Kernel

Abstract

The Linux Kernel is supported by ARM9. It is preferable to load the Root File System (RFS) using Network File System on a development system (NFS). Several pieces of software are involved to boot a linux kernel on SAM9 products. First is the ROM code which is in charge to check if a valid application is present on supported media (FLASH, DATAFLASH, NANDFLASH, and SDCARD). The linux boot procedure for SAM is subdivided into various steps, as shown below. The linux boot procedure is shown in Fig. 1. Boot Program - Check if a valid application is present in FLASH and if it is the case download it into internal SRAM. AT91Bootstrap - In charge of hardware configuration, download U-Boot binary from FLASH to SDRAM, start the bootloader U-Boot - The bootloader, in charge of download kernel binaries from FLASH, network, USB key, etc. Start the kernel. Linux kernel - The operating system kernel. Root File system - Contains applications which are executed on the target, using the OS kernel services.