Booting questions ....
Willem Jan Withagen
wjw at withagen.nl
Fri Nov 5 12:34:28 PST 2004
John Baldwin wrote:
[about the loader having flat addressspace....]
>>But is it unsegmented? (perhaps I have a wrong idea of a flat address
>>space)
>
>
> Yes, it is unsegmented. You can translate physical addresses to virtual
> addresses using PTOV() and vice versa using VTOP().
I've run accross these calls, just need to figure out how to work them.
>>What I mean with this is that I can iterate from 0xa000 to 0xffffffff with
>>a "char *p" and do test_bytes( 0xa000, 0xffffffff, 0xff). (assuming this
>>all has memory)
> Yes.
Would be nice....
>>Next is then which ranges are valid to test, and then things really start
>>to get complicated and arch dependant. Which is why I ended up in machdep.c
>>right after the setting up of the memory ranges.
>
> Heh, the above memory mapping is also i386 specific. Alpha only has a small
> bit of memory mapped in the loader, same with sparc64, etc.
Ehhhh, again more reasons to put this in the kernel, or something that closely
resembles a kernel.
--WjW
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