[openbeos] Re: is system_time(); an expensive call?

En réponse à Michael Noisternig <michael.noisternig@xxxxxxxxx>:

> François Revol wrote:
> > in x86 IOs are _not_ memory accesses, you can't map the io space to 
> > memory.
> > (but you'll have to do that for PPC).
> 
> You can do both on x86 - direct IO and memory mapped IO, e.g. the video
> memory is memory mapped.
> 

the video _memory_, not the VGA registers, which sometimes are also 
accessible in the same area as the framebuffer, but that really 
depends on the chipset. (like old S3 Trio couldn't use memory, whereas newer 
could, and even newer ones had a different (supposed to be-cleaner) 
register mapping in memory).

Once again generally, on x86 the IO space is _not_ a memory space.

François.

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