Re: [PATCH v3 01/12] misc: add driver for sequencer serial port

From: Arnd Bergmann
Date: Fri Oct 22 2010 - 08:48:33 EST


On Friday 22 October 2010 14:39:33 Cyril Chemparathy wrote:
> >> +/* Register Access Helpers */
> >> +static inline u32 ssp_read(struct ti_ssp *ssp, int reg)
> >> +{
> >> + return __raw_readl(ssp->regs + reg);
> >> +}
> >> +
> >> +static inline void ssp_write(struct ti_ssp *ssp, int reg, u32 val)
> >> +{
> >> + __raw_writel(val, ssp->regs + reg);
> >> +}
> >
> > Why are the __raw functions used here?
> >
>
> These registers are to be accessed native endian at all times, and
> therefore the le32 conversion done otherwise is inappropriate.

Won't that break on out-of-order CPUs that need the extra synchronization
done in readl/writel?

Arnd
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