Subject: Re: pmap, non-contiguous physical addresses
To: None <>
From: Michael L. Hitch <>
List: amiga-dev
Date: 03/16/1994 19:29:21
On Mar 16,  1:48pm, newsham@uhunix.uhcc.Hawaii.Edu wrote:
> ok..  I wrote those last three routines using the memory list
> (mem_list) avail_start and avail_end as well as a new variable
> that keeps track of where in mem_list we are.  I also skip
> over any chip memory (MEMF_CHIP) but not over zorroII dma-able
> memory.  Oh yah,  I assumed that the chunk of memory that we
> booted into is the first in the mem_list, is this the case?

  Not necessarily.  The kernel is normally loaded into the largest
memory segment, which may not be the first.

> If its not loadbsd can easily be changed to make it the case
> or we can re-order it in start_c I guess.

  You could check if orig_fastram_start is the start of the memory
segment in mem_list.  That will tell you which segment netbsd was
booted into.

  You also need to watch out for the Zorro II memory allocator (used
to grab memory for the GVP and A2091 disk driver bounce buffer).  You
should probably try to leave 64K of Zorro II memory free to be allocated
by the driver.


Michael L. Hitch			INTERNET:
Computer Consultant			BITNET:  OSYMH@MTSUNIX1.BITNET
Office of Systems and Computing Services
Montana State University	Bozeman, MT	USA