Fastboot

Overview

This article describes the fast boot implementation done by ISEE in IGEP boards. Fast boot must be application oriented and several key point must be tuned for archive the minimum boot time.

Development Enviroment

• Ubuntu 12.04 LTS
• Toolchain Ubuntu - linaro (arm-linux-gnueabihf-gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3) Included in Ubuntu 12.04 LTS
• IGEP-X-Loader release 3
• Minimal Rootfs generation scripts
• Linux kernel 2.6.37.y - fastboot

What we want archive?

This demostration want archive a maximum 3 sec boot time from power up to linux system ready.

The system must include the video system, ethernet, rootfs using ubi in whole NAND partition, i2c, uarts, gpio, power management, system console.

The maximum CPU clock speed must be 800 Mhz.

IGEPv2 Default system DEMO

IGEPv2 include a default linux system demo based on yocto, we will analyze the boot process.

Software Used:

Default IGEP-X-loader 2.5

Default IGEP firmware yocto based 1.2

Boot Time

IGEP-X-Loader standard takes 4.11 sec.

Linux Kernel boot time up to mount the rootfs takes 3.8 sec.

Mount the rootfs takes 14.7 sec.

Load other drivers and execute the system scripts takes 29.1 sec (including start the X and sato environment)

IGEPv2 Fast Boot DEMO

Software Used: IGEP-X-Loader version 3.0

Linux Kernel: 2.6.37.y fastboot

Boot time 

IGEP-X-Loader load time: 0.7 sec

Kernel Boot: 0.9 sec

UbiFs Mount time: 1 sec

Execute System Scripts: 0.3 sec

Improve the fast boot setup

It's possible improve the results doing some modifications:

• Disable the IGEP-X-Loader serial prints (-0.1 sec)
• The kernel is flashed uncompressed over a 6 MiB partition and IGEP-X-Loader load whole partition, we can get it small due the kernel with this setup takes 3.7 MiB (-0.25 sec)
• Disable some drivers at boot and load it after initial boot such (Video -0.35 sec, ethernet -0.02 sec)
• Create a Small footprint rootfs ubi partition or use other format faster (variable: -0.2 to -0.6 sec)

Software

You can test the fast boot setup the software package it's located here

Install Procedure

1. Download the software.
2. Create a new microsd card default firmware image.
3. Replace zImage with the zImage included in the package.
4. Boot your board and erase the partirions mtd1 and mtd2.
5. Using nandwrite write the Image kernel into mtd1.
6. Install the ubi image provided into the mtd2 partition.
7. Replace mtd0 MLO using the ISEE writeloader tool.
8. Reboot.

More information

If you wish more information or support for implement fastboot solution in your product contact us