Revision as of 12:30, 3 March 2011

Summary

X-Loader, an initial program loader for Embedded boards based on OMAP processors.

Features and Limitations

Improvements & Modifications

• Malloc/free functionality.
• Mtd framework and onenand support, removed the old onenand drivers.
• Jffs2 support using mtd & onenand support (Read Only).
• Crc32 and zlib.
• Jffs2 zlib compression support (Read Only).
• Dual boot mmc & onenand with mmc highest priority.
• Linux kernel boot directly (Support for 2.6.22 and highest version kernels)
• Linux kernel supported images: vmlinuz, bzImage and zImage.
• Support for loading Linux Ram disk (EXPERIMENTAL)
• "ini" files parser.
• The configuration resides in a plain txt (ini format file).
• Support Windows & Linux formating ini files.
• Boot from mmc, onenand, or mix with mmc highest priority.
• Codeblocks project and compilation rules.
• Support for gcc 4.5.1.
  

Limitations

• The ini configuration file it's limited to max size: 16 KiB
• Kernel Command line parameters it's limited to: 4 KiB
• Malloc it's limited to 32 MiB.
• Cannot write comments in lines with tag=value
  

TODO

• Support for IGEP0030 - Family boards.
• Support for other OMAP/DM/AM processor boards.
• Remove compilation warnings.
• Comments in tag lines
  

STATUS

• Support IGEP0020 Revision B & C family boards.
• Tested with IGEPv2 (DM3730@1Ghz and 512/512 MB Ram/Onenand)
• Tested with IGEPv2 (AM3703@1Ghz and 512/512 MB Ram/Onenand)
• Tested with IGEPv2 (OMAP3530@720Mhz and 512/512 MB Ram/Onenand)
  

Build Procedure

Build with Ubuntu Cross Compiler gcc 4.5.1

EnviromentUbuntu 10.10

Install the cross compiler if you not do it before.

apt-get install cpp-4.5-arm-linux-gnueabi g++-4.5-arm-linux-gnueabi

Setup the board settings

make igep0020-sdcard_config

Build

make

Sign the binary x-loader

You should execute contrib/signGP for sign the xloader.

contrib/signGP x-load.bin
The signed x-loader it's named: x-load.bin.ift

Build with IGEP SDK

Setup the Enviroment

source /usr/local/poky/eabi-glibc/environment-setup-arm-none-linux-gnueabi

Setup the board settings

make igep0020-sdcard_config

Build

make CROSS_COMPILE=arm-none-linux-gnueabi-

Sign the binary x-loader

You should execute contrib/signGP for sign the xloader.

contrib/signGP x-load.bin
The signed x-loader it's named: x-load.bin.ift

Build Native

Configure the board settings

make igep0020-sdcard_config

Edit the variable CFLAGS and add the option: -fno-stack-protector
CFLAGS := $(CPPFLAGS) -Wall -Wstrict-prototypes -fno-stack-protector

Build

make CROSS_COMPILE=arm-none-linux-gnueabi-

Sign the binary x-loader

You should execute contrib/signGP for sign the xloader.

contrib/signGP x-load.bin
The signed x-loader it's named: x-load.bin.ift

BOOT

The IGEP X-Loader must reside in the microSD card or in the OneNand.

MMC Boot

Prepare the microsd card

You can follow this howto about how prepare the microsd card.

4 Settings & Configuration:

================

4.1 MMC Boot
------------
Get a new mmc and create two partitions, the first one must be fat (you can follow
this howto: http://code.google.com/p/beagleboard/wiki/LinuxBootDiskFormat)
In this first partition (boot partition) you should copy:

• x-loader.bin.ift (you must rename this file to MLO) / This is a signed image using contrib/signGP tool
  * igep.ini
  * Your desired kernel image.

Don't use a uImage kernel format (from uboot), only kernel formats be supported.

Compilation Example:
$make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabi- zImage modules

Read the kernel documentation about kernel images.

4.2 Setup igep.ini file
------------------------
# Note this format permits use the characters
# '#' and ';' as comment check file size restrictions

[kernel]
kaddress=0x80008000
;rdaddress=0x84000000
serial.low=00000001
serial.high=00000000
revision=0001
;kImageName=
;kRdImageName=

[kparams]
console=ttyS2,115200n8
;earlyprintk=serial,ttyS2,115200
mem=512M
boot_delay=0
;mpurate=800
;loglevel=7
omapfb.mode=dvi:1024x768MR-16@60
smsc911x.mac=0xb2,0xb0,0x14,0xb5,0xcd,0xde
;ubi.mtd=2
;root=ubi0:igep0020-rootfs
;rootfstype=ubifs
root=/dev/mmcblk0p2 rw rootwait

Tags Supported
---------------

[kernel] ----
* kaddress=0x80008000

Kernel copy address, you should use the same address used in kernel image
configuration. If you don't know what it means maybe it's better don't change it.

• rdaddress=0x84000000
  Kernel RAM disk copy address.
  If you don't know what it means maybe it's better don't change it.

• serial.low=00000001
  * serial.high=00000000
  Board serial Number, you can read this information using /proc/cpuinfo

• revision=0001
  Board Revision ID, you can read this information using /proc/cpuinfo

• kImageName=zImage
  Kernel file name, if you don't provide this tag it try to load these others:
  // DEFAULT IMAGES
  "zImage"
  "zimage"
  "vmlinuz"
  "bzImage"
  "bzimage"

• kRdImageName=rdimage
  Kernel RAM Disk file, if you don't provide this tag it try to load these others:
  // DEFAULT IMAGES
  "initrd"

[kparams] ----
Kernel parameters, all these parameters are passed directly to the kernel using the
kernel command line.

kernel parameters documentation:
http://www.kernel.org/doc/Documentation/kernel-parameters.txt
http://www.kernel.org/pub/linux/kernel/people/gregkh/lkn/lkn_pdf/ch09.pdf

4.3 Boot Priority
-----------------
First try mmc and if it fails then try from OneNand.

Examples:
a) MLO (x-loader), igep.ini, zImage from MMC
If all it's present in the mmc it don't try to boot from Onenand.

b) MLO (x-loader) in MMC, igep.ini and zImage in Onenand.
If only MLO it's provided this one try to load the other information from
the Onenand.

4.4 OneNand Partition settings
-------------------------------
We suggest use minimum 3 partitions on the OneNand.

Creating 3 MTD partitions on "omap2-onenand":
0x000000000000-0x000000080000 : "X-Loader"
0x000000080000-0x000000c80000 : "Boot"
0x000000c80000-0x000020000000 : "File System"

4.4.1) Xloader partition
* Not fs formated (raw)
* Suggested size: 0x80000 (512 KiB)
* The xloader must be signed before copy it in the flash memory.

You should copy the x-loader in the firsts 4 blocks (first 512 KiB), this is not a
formated partition due the ROM not permits boot from there, you should use tools:
flash_eraseall and nandwrite for copy x-loader in the first blocks.

Suggested procedure:

nand_eraseall /dev/mtd0
nandwrite -p /dev/mtd0 <x-loader>

• Sign x-loader
  You should execute contrib/signGP for sign the xloader that resides inside the flash memory.

contrib/signGP x-load.bin
The signed x-loader it's named: x-load.bin.ift

Due the Onenand 512 MiB has two dies it's necessary split the x-loader and convert it to a 1 die binary.
This is a know OMAP/DM/AM OneNand/Nand boot limitation.

This is the procedure for create the x-loader OneNand binary:
You should execute: (You can use copy paste in your console)

split -b 2K x-load.bin.ift split-
for file in `ls split-a?`; do cat $file >> x-load-ddp.bin.ift; cat $file >> x-load-ddp.bin.ift; done

This last command generate a file named x-load-ddp.bin.ift this is the x-loader for copy it in the OneNand.

4.4.2 Boot Partition
--------------------
* fs used jffs2 zlib compressed filesystem.
* Suggested size: 0xC00000 (12 MiB)

First time creation:
a) Use the same procedure described in point 4.2.1. Copy your jffs2 compressed image in the
partition, it can be a empty file.

b) Erase the partition and mount it as jffs2 filesystem then you can copy with cp command.

Next Times:
Copy the files using cp command, or edit directly.

when kernel boots you can enable mount this partition over /boot directory for access all boot content.

4.4.3 Rootfs
------------
* fs (your prefered fs supported by linux, maybe a good choice it should be ubifs)
* Size, all or you can create more partitions if you wish ...

5 Build procedure
=================

5.1 Build with Ubuntu Cross Compiler gcc 4.5.1

• This is tested with Ubuntu 10.10

a) Install the cross compiler:
apt-get install cpp-4.5-arm-linux-gnueabi g++-4.5-arm-linux-gnueabi

b) Configure the board
make igep0020-sdcard_config

c) Build
make

d) Sign x-loader
You should execute contrib/signGP for sign the xloader that resides inside the flash memory.
contrib/signGP x-load.bin
The signed x-loader it's named: x-load.bin.ift

5.2 Build with IGEP SDK

a) Source the enviroment
source /usr/local/poky/eabi-glibc/environment-setup-arm-none-linux-gnueabi

b) Edit the file Makefile
Find the define:

And Set the variable as:
CROSS_COMPILE = arm-none-linux-gnueabi-

b) Configure the board
make igep0020-sdcard_config

c) build
make

d) Sign x-loader
You should execute contrib/signGP for sign the xloader that resides inside the flash memory.
contrib/signGP x-load.bin
The signed x-loader it's named: x-load.bin.ift

5.3 Build Native

a) Configure the board
make igep0020-sdcard_config

b) Modify the config.mk file
Edit the variable CFLAGS and add the option: -fno-stack-protector

CFLAGS := $(CPPFLAGS) -Wall -Wstrict-prototypes -fno-stack-protector

c) build
make CROSS_COMPILE=""

d) Sign x-loader
You should execute contrib/signGP for sign the xloader that resides inside the flash memory.
contrib/signGP x-load.bin
The signed x-loader it's named: x-load.bin.ift

6 Contribution & Support & Report Bugs
======================================
Contributions to this project be welcome and you can send your patches to support@iseebcn.com
or you can use the igep forum for it.
You can access to IGEP-x-Loader repository using our git at git.igep.es
IGEP IRC Channel: http://webchat.freenode.net/?channels=igep