PPC beginner questions

Grant Likely grant.likely at secretlab.ca
Tue Aug 22 02:24:42 EST 2006

On 8/21/06, Wade Maxfield <wmaxfield at gmail.com> wrote:
> On 8/21/06, Grant Likely <grant.likely at secretlab.ca > wrote:
> > On 8/21/06, Wade Maxfield <wmaxfield at gmail.com > wrote:

> > >   I'm assuming inb() outb(), inw() outw()??  I've been googling and have
> > > come up short with info that makes sense. It is almost all x86 centric.
> >
> > in_8, in_be16, in_be32, out_8, out_be16, out_be32 for big-endian
> > device registers
> > in_8, in_le16, in_le32, out_8, out_le16, out_le32 for little endian
> > device registers
> -->Interesting.  Do these functions do 'eieio'  (Email, Internet, Electronic
> Information Officer functions (southpark cartoon), err, or  Enforce In-Order
> Execution of Input/Output) for me, or do I have to do that?  I'm still
> confused as to that Old MacDonald function.

The in functions do isync
The out functions do eieio

> >
> > heh, yes you can; but if your writing new code why not use good
> > practice from the start?  :)
> --> Ok, you win.  How about ioread8() or inb() also?  Are they not coded in
> PPC correctly? Or is the in_8() more modern?

read include/asm/io.h.  All the IO routines are defined there.
read[bwl] and write[bwl] are just macros to in_* out_*, as are inb,
outb, etc.


Grant Likely, B.Sc. P.Eng.
Secret Lab Technologies Ltd.
grant.likely at secretlab.ca
(403) 399-0195

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