On Wed, 2003-02-05 at 12:16, Felix Radensky wrote:
Hi, Christopher
Thanks a lot for the code. I really appreciate it ! Did you modify the linuxbios itself to allow VxWorks to be loaded at 8000h. I guess I have to modify ldscript.ld but i don't know how.
Thanks a lot.
Felix.
Two years ago(?), working from an old tarball on a 430TX-based board, I threw the quoted C code in where the jump to the linux kernel normally goes, and apparently I modified the GDT as well. The experiment convinced us to go this route for our PIII BX board running a different RTOS instead of buying a BIOS solely for its SDRAM init, pci enumeration, & disk boot capabilities.
If there is a cleaner switch to real mode available now, use it. (You can see that I was patching code in ram in order to jump to a 16-bit protected mode segment, and that the chipset wasn't entirely cooperating.) You might also look to see if there is a protected mode entry point to your vxWorks code. I don't know if that is feasible or not. We haven't done vxWorks for 2 years, and only a couple printed manuals were saved from the Great Purge.