Linux Support for the ARM Architecture

Overview

The filesystem images available on this page include a set of applications tested with ARM RealView^® platforms. More complete filesystems can be built using information and packages supplied on www.linaro.org.

The 2.6 Linux kernel provided on these pages include support for the following processors:

• ARM720T^*, ARM920T^*, ARM922T^*, ARM926EJ-S
• ARM1136J(F)-S, ARM1176JZ(F)-S, ARM11 MPCore
• Cortex-A8, Cortex-A9, Cortex-A5, Cortex-A15

The following components are provided to support these platforms:

• Boot loader: U-Boot
• Pre-built Linux kernel, including sources and a binary image
• Configuration files for building the kernel
• Filesystem with pre-built utilities and applications
• Notes describing Linux installation

Pre-built Kernel Images

A copy of the mkImage utility used to produce U-Boot images is available from the following link.

Patch-2.6.38-arm1.gz (1.5MB) should be used against kernel.org 2.6.38 kernel source tree to produce the binary kernel images supplied on this page. This patch includes support for running the Linux kernel in Thumb-2 state on ARMv7 processors.

The kernel provided with this release is compiled with EABI support and supports running of Thumb-2 based applications, handling of VFP and NEON registers. 

The Linux kernel include support for the following Primecells:

• UART (PL010, PL011), Interrupt Controller (VIC, GIC), KMI (PL050), RTC (PL030), Timers
• VGA/LCD (PL110), AACI (PL041), VFP, Ethernet (PL092), LAN9118, LAN91C111, MMC
• L2CC (PL220, PL310), USB

U-Boot binaries available for download on this page have been compiled from the following Sources. Patches are also contributed to the U-Boot project list.

Pre-built Filesystem Images

The following images can be used with each ARM platform:

• Minimal ARMv5T cramfs (30 MB) - with debug symbols, no X11 or optional applications
• Minimal ARMv6 cramfs (30 MB) - with debug symbols, no X11 or optional applications
• Minimal ARMv7 Thumb-2 cramfs (30 MB) - compiled for Thumb-2 with NEON support
• Full ARMv5T cramfs (49 MB) - with X11 and optional applications
• Full ARMv6 cramfs (49 MB) - with X11 and optional applications
• Full ARMv7 Thumb-2 cramfs (47 MB) - compiled for Thumb-2 with NEON support

Please consult the README file in the ARM Embedded Linux repository with regard to access to the source code of these packages. Information about ARM public GIT repositories is available at the following location.

These images have been generated using GCC 4.5.1 and GNU libc 2.11.

(**) Note that on RealView PBX-A9 not all of the cores on this board have NEON. When running applications with NEON, one should check which CPU these are executed on. The pre-built ARMv6 cramfs should run without problem on this platform.

Licensing

The source code used to build these binary packages is available under the terms of the GNU Public License. This software is provided with NO WARRANTY, to the extent permitted by applicable law. The software is provided "as is" without warranty of any kind, either expressed or implied, including the implied warranties of merchantability or fitness for a particular purpose.

Note

Only pre-built images for ARM processors from ARMv5T onwards are provided on this page. Images for ARMv4 processors, marked with an asterisk (*) in the above processor list, can be built from source.

Overview

Processors without an MMU can run a modified version of Linux called uClinux. The filesystem images and patches provided on this page include support for uClinux including a set of applications tested with ARM RealView platforms. These are available for the following ARM processors:

• ARM946E-S
• ARM1156T2-S
• Cortex-R4(F)

Please refer to www.uclinux.org for more information, documentation, mailing lists and additional resources. The table below contains pre-built uClinux image for ARM RealView platforms for ARM1156 and Cortex-R4.

Patch-2.6.35-arm1.gz (187 KB) contains necessary changes to be applied against 2.6.35 kernel source tree to produce binary uClinux kernel images. These kernel images have been produced using GNU GCC 4.3.2.

The following filesystem images can be used with the supplied uClinux kernel images:  

• Base cramfs (2.5 MB) - Base uClinux applications and libraries cramfs image
• Thumb-2 cramfs (3 MB) - Thumb-2 uClinux applications and libraries cramfs image

The uClinux filesystem images were produced from BuildRoot.

Licensing

The source code used to build these binary packages is available under the terms of the GNU Public License. This software is provided with NO WARRANTY, to the extent permitted by applicable law. The software is provided "as is" without warranty of any kind, either expressed or implied, including the implied warranties of merchantability or fitness for a particular purpose.

Overview

Android is a software stack for mobile devices using the Linux kernel and applications. The Android SDK provides the tools and APIs to develop applications on Android platforms using the Java programming language. Android applications run in their own process with their own instance of the Dalvik Virtual Machine (VM). Dalvik is a register-based virtual machine (as opposed to JVM which is a stack-based virtual machine) and executes classes compiled by a Java-like language compiler. Performance-critical applications can be written in native code using the Android NDK which is a companion tool to the SDK. ARM software enablement blog section includes entries on how to setup and run Android on ARM platforms (see the following article).

This page includes information and sample instructions on how to build and run Android on ARM RealView^® platforms using Linux kernel versions available from http://www.arm.com/linux. Both GIT version-control system and the Repo tool built on top of GIT are used to manipulate the source code.

In addition, the ARM Solution Center for Android (SCA) offers resources to developers who are new to Android or to ARM. 

Pre-built kernel images

The armdroid1 patch is to be applied on 2.6.38 vanilla kernel. The source tree is also available on the following git repo.

The following image is a pre-built (plain) 2.6.38 Linux kernel for Cortex-A5 core tile on Versatile Express with corresponding config file.

A set of detailed instructions on how to build Android for ARM RealView platforms are available on the Linux-arm.org Wiki page complementing recent blog posts.

Licensing

The source code used to build these binary packages is available under the terms of the GNU Public License. This software is provided with NO WARRANTY, to the extent permitted by applicable law. The software is provided "as is" without warranty of any kind, either expressed or implied, including the implied warranties of merchantability or fitness for a particular purpose.

Processors and Related Technology

• Cortex-A5, Cortex-A9, Cortex-A8, ARM1176, ARM1136, ARM926,
• Cortex-R4, Cortex-M3, ARM1156, ARM946
• TrustZone
• NEON

Graphics

• Mali-200
• Mali-400 MP

Software Development

• OpenMAX software libraries
• RealView Development Boards
• Mali Developer Center