Thank you for your reply Wolfgang! In u-boot-1.1.4 README "Where we come from" section, it says u-boot "provide extended interface to Linux boot loader". Does it mean that there is still some sort of boot loader in arch/ppc/coffboot/vmlinux.gz ? If yes, when does it start? Does it boot the kernel?
To build u-boot, I will need to get the manual for MPC852 and check the configurations in include/configs/TQM860L.h file. I am trying to find the machine specific header file in linux-2.4.25 (include/asm-ppc/tqm8xx.h file in linux-2.4.4) which should have the same definition of structure bd_info as in include/asm-ppc/u-boot.h. And you recommend using linux-2.4 instead of linux-2.6 on your website. So am I heading the right directions here? Because the u-boot README doesn't have the new directories and filenames, I am a little confused. Thanks again, Jessica > > I am new to embedded system, I am studying ppcboot-1.1.5 and linux > > kernel-2.4.4 that comes with an mpc852 base board, we want to modify it in > > Both PPCBoot and Linux 2.4.4 are *hoplessly* obsolete. It may be ok > to study this to understand the workings, but please don't even dream > of using it for any current work. > > > the future. In the build process, they use the zImage.initrd > > (arch/ppc/mbxboot/zvmlinux.initrd) instead of the raw Linux kernel image > > Somebody didn't know what he was doing, it seems. > > > since ppcboot is already running, what happens when I boot the kernel that > > has old boot loader code in arch/ppc/mbxboot? Will some parameters be > > overwritten? If not, why? > > The Linux bootstrap loader code (arch/ppc/mbxboot) will ignore the > parameteres passed by U-Boot, will set up is own (hardwired), and > duplicate some of the things that PPCboot did or would do. > > > I am very tempted to follow the README to re-build the kernel with only > > vmlinux.gz and port it, but I don't want to create any un-recoverable > > results. So I am here to seek advice, maybe this is something obvious to > > many people. > > Don't change anything. Look at it, then drop it. Start using current > code, i. e. a recent version of U-Boot and a recent Linux kernel.
