Re: [PATCH] Clarify pci_iomap() usage for MMIO-only devices

["Nick Kossifidis" <mickflemm@gmail.com>]

2007/9/19, Alan Cox <alan@lxorguk.ukuu.org.uk>:
> > If you use ioport_map/unmap, then you really *should* access them with the
> > proper iomem accessors (ioread/iowrite). The fact that it may happen to
> > work (when using the default lib/iomap.c implementation, at least) on
> > some architectures and with the current implementation still doesn't mean
> > that you should necessarily use readb/writeb.
>
> Another reason we should enforce the use of ioread/iowrite is that some
> platforms do daft things like map mmio type devices through indirect
> register access. Sparc PCMCIA is a classic example. The only sane way to
> make these work is to require ioread/iowrite is used with iomap
>

Hmm, we 've had bug reports about driver (madwifi-old-openhal) not
working on Sparc64, can someone test if this is the case (the fact
that we used readl/writel instead of ioread/iowrite on
madwifi-old-openhal) ? It was really weird because we handle
big-endian machines ok (madwifi-old-openhal on ppc worked fine).

(ath5k was based on madwifi-old-openhal)

-- 
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As you read this post global entropy rises. Have Fun ;-)
Nick
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