Re: unsigned long ioremap()?

From: Abramo Bagnara (abramo@alsa-project.org)
Date: Sun May 13 2001 - 09:38:55 EST

Jes Sorensen wrote:
>
> >>>>> "Abramo" == Abramo Bagnara <abramo@alsa-project.org> writes:
>
> Abramo> "David S. Miller" wrote:
> >> One final point, I want to reiterate that I believe:
> >>
> >> foo = readl(&regs->bar);
> >>
> >> is perfectly legal and should not be discouraged and in particular,
> >> not made painful to do.
>
> Abramo> I disagree: regs it's not a dereferenceable thing and I think
> Abramo> it's an abuse of pointer type. You're keeping a pointer that
> Abramo> need a big sign on it saying "Don't dereference me", it's a
> Abramo> mess.
>
> Thats complete rubbish, in many cases the regs structure matches a
> regs structure seen by another CPU on the other side of the PCI bus
> (ie. the firmware case). There is nothing wrong with the above
> approach as long as you keep in mind that you cannot dereference the
> struct without using readl and you have to make sure to explicitly do
> padding in the struct (not all CPUs guarantee the same natural
> alignment).

"As long as you handle with gloves thick enough such a shit, there's no
problems.." 

-- 
Abramo Bagnara                       mailto:abramo@alsa-project.org

Opera Unica                          Phone: +39.546.656023
Via Emilia Interna, 140
48014 Castel Bolognese (RA) - Italy

ALSA project               http://www.alsa-project.org
It sounds good!
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This archive was generated by hypermail 2b29 : Tue May 15 2001 - 21:00:32 EST