Thread: memory mapped IO: device registers mapped to virtual memory or physical memory?
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Old February 1st 06, 06:51 PM posted to alt.os.development,comp.unix.internals,comp.unix.programmer,alt.comp.hardware
Maxim S. Shatskih
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Default memory mapped IO: device registers mapped to virtual memory or physical memory?
They are mapped to physical by hardware, and then also to virtual by the
OS - by a call like Windows's MmMapIoSpace.

--
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation

http://www.storagecraft.com

"Olumide" wrote in message
oups.com...
Hi -

I know memory mapped IO is about mapping device/controller registers to
memory space in order to reduce the number of processor instructions
(and simplify device driver writing) . My question is: are device
registers mapped to virtual memory or physical memory? I suspect the
former, and I have looked up a number of texts but everyone just seems
to skirt about the issue.

Thanks,

- Olumide