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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