[linuxdc-dev]Memeory mapping

[Adrian M. <ad...@mc...>]

At last I feel I am beginning to understand how to do this (write the sound 
driver) but I have a question about memory mapping, or rather wonder if 
soemone will confirm my understanding of the DC memory map - as there are a 
plethora of memory maps out there saying different things....

The memory map appears to repeat itself over and over again, but the kernel 
is in the P1 area and (obviously) executes as privileged code with the bottom 
of system RAM at 0x80000000?

Now, I assume that for a sound driver should also access the sound memory in 
privileged mode so that's at 0x80800000 for the driver? (Can ill-behaved user 
programs then write all over that - or does the kernel memory management stop 
them?)

Meanwhile the sound registers are only accessible in privileged mode - as 
they are mapped (for the SH4) into 0xa0700000 - 0xa07033ff - or can these be 
reached at 0x80700000 - 0x808033ff too? Or even in user space at 0x0070000 
etc?

Adrian