On 12.02.2004 12:03:48 CET Manuel Bouyer wrote:
>
>On Wed, Feb 11, 2004 at 11:42:38PM +0100, Christian Groessler wrote:
>> >I didn't see anything wrong in you code, but what is this MEM area you're
>> >trying to map ?
>>
>> It's a dual processor i486 + i860 board. One can split the installed
>> memory btw. the two processors. The i486 mem starts at address 0
>> growing upwards, and the i860 mem starts at 0xffffffff growing
>> downwards.
>>
>> I want to map the i860 memory to be able to load i860 programs and run
>> them there.
>
>Is it the same chunk of memory shared by both processors, or 2 processors
>with their own memory, and interconnected by some I/O bus (e.g. isa or PCI) ?
>bus_space deals with the second case, but not the first. For the first case,
>you can map it using UVM functions.

The memory is shared by both processors. The i486 can access the i860
memory by accessing physical address 0xffffffff or lower, and the i860
can access the i486 memory by accessing address 0 or higher.

So the UVM functions seem to be right. Is there somewhere an example
on how to use them to map a memory region?

regards,
chris