Difference between revisions of "BootLoader"

Revision as of 21:02, 27 January 2007

Introduction

This page describe the U-Boot installation/usage in the Armadeus context.

Build U-Boot

Build process is now part of the Armadeus package. The process is automated in the global build process (see Install Armadeus software), So the following information is only usefull for a manual build process:

• Download Das U-Boot source code archive from: http://sourceforge.net/project/showfiles.php?group_id=65938
• Uncompress it:

   tar jxvf u-boot-1.1.3.tar.bz2

• Download Armadeus patches corresponding to your u-boot & gcc version from: http://fr.groups.yahoo.com/group/armadeus/files/Patches/ and copy it to the u-boot directory.
• Go inside the u-boot directory and apply the patches (here for u-boot1.1.3):

   patch -p1 < u-boot1.1.3-apm9328-2.1.patch
   patch -p1 < u-boot1.1-gcc3.4.patch (if necessary)

If you have a 8 or 16MB apm9328 board, edit the include/configs/apm9328.h. look for a #define SDRAM_xxxMBIT change it to a:

   * #define SDRAM_64MBIT /* for 8MB */
   * #define SDRAM_128MBIT /* for 16MB */
   * #define SDRAM_256MBIT /* for 32MB */

Then build u-boot:

   make apm9328_config
   make

this produce a u-boot.bin and a u-boot.brec file:

• u-boot.bin is a binary image file and can be downloaded with the u-boot loadb command (or tftpboot, nfs,...)
• u-boot-brec is a boostrap record file compatible with the freescale bootloader. Use the kermit transmit command.

Install or restore from scratch

If your Armadeus board doesn't boot anymore (flash content erased or dammaged), you will have to use the bootstrap mode of the i.MX.
Use the jumper to boot the integrated freescale bootstrap.
check your host .kermrc file and add the following line:

   set transmit linefeed on 

Then connect to the apm9328:

   kermit 

   c 

Synchronize baudrate by pressing the 'A' key until you receive the character ':' then press return to validate the synchronization.
Go back to command mode

   <CTRL><ALT GR>\ 

   c 

Then transmit the u-boot.brec file:

   transmit armadeus_path/software/buildroot/u-boot.brec 

This process can take a couple of minutes. U-boot is now running in RAM. make a new connection to check you have prompt: BIOS> You can burn u-boot in flash memory. see Update u-boot hereafter. Then remove the jumper to use u-boot at the next power-up.

For faster restoring you can use BootStrap utility too.

Update U-Boot

There are two steps to update u-boot:

• 1] Load the new u-boot code in RAM

You can use the following commands to download U-boot. With ethernet and a tftpboot server:

   tftpboot 08000000 /tftpboot_path_to_buildroot/u-boot.bin

With ethernet and a nfs server:

   nfs 08000000 host_ip_addr:/nfs_path_to_buildroot/u-boot.bin

With the kermit and a serial line

   loadb
   <CTRL><ALT GR>\
   c
   send path_to_buildroot/u_boot.bin
   c

• 2] Transfer code from RAM to Flash memory

There is a simple u-boot command/script to do that:

   run flash_uboot

Modify your environment variables

There is a set of variables you can customize to your needs. The commande printenv show you most of them and their current state. Use the command setenv to change one of these variable. For instance:

setenv ipaddr 192.168.0.3

Use the command saveenv to save the state of your environment variables in flash memory.

Customize the flash memory organization

Booting Linux

The Install Armadeus software on target provide some information to install linux on Armadeus board

Customize Linux boot mode

Typical Kermit (.kermrc) config file

set line /dev/ttyS0
set speed 115200
set carrier-watch off
set handshake none
set flow-control none
robust
set file type bin
set file name lit
set rec pack 1000
set send pack 1000
set window 5
set transmit linefeed on

Links

• http://www.denx.de/wiki/DULG/Manual