Linux Kernel

Introduction

Android4SAM kernel is based on Linux kernel 2.6.35, with Android experimental patch applied orderly.

For more information, please refer to Linux4SAM

Pre-built images

	SAM9M10 MCU	SAM9G45 MCU	SAM9X5 MCU
Nandflash Booting	linux-2.6.35-sam9m10-nf-uImage	linux-2.6.35-sam9g45-nf-uImage	linux-2.6.35-sam9x5-nf-uImage
SD Card Booting	linux-2.6.35-sam9m10-sd-uImage	linux-2.6.35-sam9g45-sd-uImage	linux-2.6.35-sam9x5-sd-uImage

Android4SAM pre-built kernel image is included in Android4SAM demo package. It is of U-Boot format.

Download

AT91 Linux Kernel Source

Linux Kernel revision	Vanilla Linux Kernel	Atmel patch	Android4SAM patch
Linux 2.6.35	linux-2.6.35.tar.bz2	linux-2.6.35.diff	linux-2.6.35_Android-2.3.5_r1.diff

You need to apply the patch from left to right orderly.

Patch Description

Atmel Patch (linux-2.6.35.diff)

This patch series adds the support for 5-Series boards in Linux 2.6.35

Android4SAM Patch (linux-2.6.35_Android-2.3.5_r1.diff)

• Add hardware video decoder driver for sam9m10 chip
• Add ISI driver for camera applicaton
• Add dummy battery driver which is needed for android
• Add LCD double buffer driver which is needed for android
• Modify the NAND flash partition table
• Modify touchscreen driver to make it more accurate
• Modify LCD driver to make it not flicker under android
• Modify button driver to make the button work well under android
• Add QT1070 button support on 5-Series EK boards

Build

Get and Patch

To get an experimental Android4SAM kernel up and running on an AT91 product, please go through the following steps:

1. Download the corresponding Linux kernel, for example, we use 2.6.35 kernel.

$ wget http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.35.tar.bz2
$ tar xvjf linux-2.6.35.tar.bz2

2. Download the ATMEL's patch and apply it

$ wget ftp://ftp.linux4sam.org/pub/Android4SAM/v2.0/patches/linux-2.6.35.diff
$ cd linux-2.6.35
$ patch -p1 < ../linux-2.6.35.diff
$ cd ..

3. Download Android4SAM patch and apply it

$ wget ftp://ftp.linux4sam.org/pub/Android4SAM/v2.0/patches/linux-2.6.35_Android-2.3.5_r1.diff 
$ cd linux-2.6.35
$ patch -p1 < ../linux-2.6.35_Android-2.3.5_r1.diff 
$ cd ..

You now have an Android4SAM Linux kernel.

Configure and Build Linux Kernel

Now you need to configure the Linux Kernel according to your hardware. We provided a default configuration file in the patchset for you to use.

$ cd linux-2.6.35
$ make mrproper

1. For NAND Flash boot
You need to BuildAndroid before this step, and copy mydroid/out/target/product/sam9m10/root (sam9m10 as an example) directory to linux-2.6.35 directory

• For AT91SAM9M10-G45-EK board with SAM9G45 MCU:

  $ make ARCH=arm at91sam9g45_android_ubifs_defconfig 
  

• For AT91SAM9M10-G45-EK board with SAM9M10 MCU:

  $ make ARCH=arm at91sam9m10_android_ubifs_defconfig 
  

• For AT91SAM9x5-EK board with SAM9G15, SAM9G35, SAM9X35 MCU:

  $ make ARCH=arm at91sam9x5_android_ubifs_defconfig 
  

2. For SD Card boot

• For AT91SAM9M10-G45-EK board with SAM9G45 MCU:

  $ make ARCH=arm at91sam9g45_android_sdcard_defconfig 
  

• For AT91SAM9M10-G45-EK board with SAM9M10 MCU:

  $ make ARCH=arm at91sam9m10_android_sdcard_defconfig 
  

• For AT91SAM9x5-EK board with SAM9G15, SAM9G35, SAM9x35 MCU:

  $ make ARCH=arm at91sam9x5_android_sdcard_defconfig 
  

3. At this step, you can modify default configuration (Optional)

$ make ARCH=arm menuconfig 

4. And build the Linux kernel image

$ make uImage ARCH=arm  CROSS_COMPILE=<path_to_cross-compiler/cross-compiler-prefix->

After finish successfully, you can find kernel image in: arch/arm/boot/uImage

NOTE: Make sure "mkimage" command can be found in your current path, otherwise U-Boot style image cannot be built.

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See also: AndroidRootfs, DemoArchives