On Thu, 18 Oct 2001, Atsushi Nemoto wrote:
> >>>>> On Wed, 17 Oct 2001 20:43:58 +0900 (JST), Atsushi Nemoto <nemoto@toshiba-tops.co.jp> said:
> nemoto> Yes, I depend on hardware swapping on word/dword access. It
> nemoto> seems many pci drivers depend on this swapping too.
>
> Sorry, last sentence might be wrong. I doubt I have been
> misunderstanding long time...
>
> Can anybody explain me a PCI driver's policy of endianness? Should we
> use cpu_to_le32 with outl/writel? Should we use cpu_to_le32 to write
> 32bit data to DMA area?
The PCI bus is little-endian.
All accesses should be done using one of
- {read,write}[bwlq]: PCI memory space
- {in,out}[bwl]: PCI (and ISA) I/O space
- isa_{read,write}[bwl]: ISA memory space
The functions above should take care of endian conversion.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
