BAT setting after bootrom? and where to load elf image?

[Tim Lai]

Hi, I am new to linux and trying to get some help from
some linux experts out here. I've been reading and
searching the mail list archive for the past few
weeks.
Here is what I have so far:

I have a ppc750 broad with vxWorks bootrom. I do not
have any device to reflash the broad. I read one of
the mail archive that someone write a program to
work with vxWorks bootrom. And this is what I want
to do. I plan to convert the vmlinux image to asm and
put it in the .text section of another elf file.
Load this elf file and relocate the vmlinux image to
0xC000000. Is this a feasible approach?

After the vxWorks bootrom come up, the BAT setting is
phy = virt. The board has 8Meg of RAM. Knowing the
linux kernel need to be at 0xC000000, should I change
the BAT setting to map 7-8M to 0xC0000000, then
copy the image to 0xC0000000?

I am a little confuse about the MMU in linux. Here is
what I understand:
after the bootrom, the CPU MMU should be phy = virt
after linux booted, linux MMU takes over, and kernel
space is 0xc0000000, and user space is 0x0 to
0xc0000000. What happened in between? Who is
responible for doing the mapping?

Thanks in advances.

Tim Lai


** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/