Chapter 3 Tools, Operating Systems and Boards——Cortex-A Series Programmer's Guide

1. You can obtain pre-built Linux images, or read the Linux on ARM Wiki at http://www.linux-arm.org.

2. The ARM Embedded Linux distribution only includes the kernel. 

3. The filesystem and U-Boot bootloader are available through Linaro. http://www.linaro.org/

Its focus is on tools to help you write and debug code, on ow-level software which interacts 

with the underlying hardware and on key pieces of middleware. Linaro engineers work on the 

kernel and tools, graphics and multimedia and power.Linaro engineers work on the kernel and 

tools, graphics and multimedia and power.

4. These virtual files mean that we don’t have to know how to program the kernel to access many 

hardwe are features. An example is /proc/cpuinfo. 

5. Useful tools

    QEMU
It can run operating systems and applications made for one machine (for example, an ARM processor) on a different machine,such as a PC or Mac. It uses dynamic translation of instructions and can achieve useful levels of performance, enabling it to boot  complex operating systems like Linux, without the need for any target hardware.

    BusyBox
BusyBox is a single binary executable which combines many applications.the large number of tools packed into a small package. 

    Scratchbox

Scratchbox is a cross-compilation toolkit which solves these problems and gives the necessary tools to cross-compile a complete Linux distribution. It can use either QEMU or a target board to execute the cross-compiled binaries it produces.

    UEFI and Tianocore
The Unified Extensible Firmware Interface (UEFI) is the specification of an interface tohand-off control of a system from the pre-boot environment to an operating system, such asWindows or Linux. Its modular design permits flexibility in the functionality provided in thepre-boot environment and eases porting to new hardware. The UEFI forum is a non-profitcollaborative trade organization formed to promote and manage the UEFI standard.UEFI is processor architecture independent and the Tianocore EFI Development Kit 2 (EDK2)is available under a BSD license. It contains UEFI support for ARM platforms, including ARMVersatile Express boards and the BeagleBoard (see BeagleBoard on page 3-13).See http://www.uefi.org and http://sourceforge.net/apps/mediawiki/tianocore for moreinformation.