🚀 go-pugleaf

I'm searching for a couple of particular details on address translations
within the context of a device driver....

Firstly, under UNIX System V/88 R32V3 in particular, and UNIX System V in
general, what kernel address space is automatically mapped to physical 
memory? Teixeira, in his device driver text, says the kernel always maps
the upper 2 Mbytes of kernel address space to identical physical addresses.
Is this true for 88k, ie 0xFFE00000 - 0xFFFFFFFF references in kernel space
will try to access these physical addresses? I can't find any V/88
documentation that confirms or denies this (and I am not at device
driver debugging stage yet...) although samples of code I've looked at
definitely assume that this is the case.

If so, that covers accessing device registers, but how do I access 
primary memory that has been removed from UNIX via  sysgen configuration? 
For example, memory from 0x01FE0000 - 0x02000000 I want to access via my 
device driver. I've searched the documentation for some routine/method that 
allows me somehow directly access physical memory, but to no avail. 
Do I have to do something special/bypass address translation tables 
(if so, what/how ??!?), or is there simple solution? (ie a copyin/copyout
that works between kernel space and physical space...)

Thanks for any assistance
Graham Hausler.





-- 
Internet:   hausler@aldetec.oz.au      --> GEMCO, Perth, Australia.