io.h and I/O port access from user space

Hollis Blanchard hollis at
Wed Feb 6 08:48:10 EST 2002

On Tue, 2002-02-05 at 14:34, Jeffrey D. Kowing wrote:
> Is there suppose to be a <sys/io.h> for powerpc platforms ?

I guess not. I'm not a glibc person though...

> What include file should I use to get inb/outb defined for a user
> space program.  (This is a linuxppc 2.4.x kernel I'm working with.)

I'm not sure there are any.

> I guess it is still the case for the linuxppc-2.4.x series that I need
> to mmap /dev/mem first as per Geert's advice in
> advice?

Yes, you certainly need to mmap /dev/mem.

> Has anyone in powerpc land used the isapnptools ?

I guess the obvious question is do you have ISA slots in the system
you're trying to build for? And you don't want to use the in-kernel
stuff? Do you really *need* isapnptools? :)

If you have ISA, it's probably a PReP? I've done user space IO simply by
mmap'ing (offset = 0x80000000), then just doing accesses normally:
	(char *)ioregion = mmap(...)
	ioregion[0x3fc] = 0x1;


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