FDI LPC3180, User Manual, Page: 10 / 34

FDI
NXP LPC3180 Demo
User’s Manual
FDI
Rev 2 Page 10 10/1/2007
5.2 U-Boot
U-Boot is another boot loader which is mainly responsible for loading the Linux Kernel.
It also provides a number of useful utilities. For example, the auto-boot process can be
aborted and a command line system accessed to handle flashing of the NAND, memory
testing, and other basic low level features (read/write individual bytes). If left to run, U-
Boot will automatically start up the Linux system.
5.3 Linux Boot
Linux is loaded using a standard SysV Init method. As the kernel enters various run-
levels scripts are executed which start specific daemons. One script run is the
/etc/rcS.d/S40modprobe.sh script. This file is actually a symbolic link to a script located
in /lib/modules/2.6.10/S40modprobe.sh. This script modprobes drivers on boot and may
be modified depending on the level of functionality desired in the bootable kernel.
After the kernel finishes booting, the login prompt is observable from the HyperTerminal
window. At this prompt, the user may log in by typing ‘root’ as the username with no
password:
Copacabana - ARM Embedded Linux version 1.1-vfp
Monday 20 December 2004 @ 20:40
(none) login:
5.4 SDRAM Memory Map
Although the images loaded into SDRAM depend on the parameters in the .ubt files,
below is the standard configuration used. The following depicts where the images are
loaded into memory, but the memory map may change as sections are uncompressed
and/or moved.
Section Address Start
RootFS 0x80000000
Linux Kernel
0x80620000
U-Boot 0x81EC0000
5.5 NAND Flash Memory Map
The NAND Flash is split into the following sections:
Section Address Start
Interface Configuration data (ICR) 0x00000000
Secondary Boot Loader (SIBL)
0x00000800
RootFS 0x00020000
Linux Kernel
0x00620000
U-Boot 0x00800000
JFFS2 file system
0x01000000