[PATCH v5 1/3] ARM: Introduce atomic MMIO modify

[ezequiel.garcia@free-electrons.com (Ezequiel Garcia)]

On Tue, Dec 10, 2013 at 05:00:25PM +0000, Russell King - ARM Linux wrote:
> On Tue, Dec 10, 2013 at 04:49:07PM +0000, Mark Brown wrote:
> > On Tue, Dec 10, 2013 at 11:41:35AM -0300, Ezequiel Garcia wrote:
> > 
> > > +void atomic_io_modify_relaxed(void __iomem *reg, u32 mask, u32 set)
> > > +{
> > > +	unsigned long flags;
> > > +	u32 value;
> > > +
> > > +	raw_spin_lock_irqsave(&__io_lock, flags);
> > > +	value = readl_relaxed(reg) & ~mask;
> > > +	value |= (set & mask);
> > > +	writel_relaxed(value, reg);
> > > +	raw_spin_unlock_irqrestore(&__io_lock, flags);
> > > +}
> > > +EXPORT_SYMBOL(atomic_io_modify_relaxed);
> > 
> > This looks quite generic - why is it in architecture specific code?
> 
> because the _relaxed IO operators don't exist on other architectures, and
> there's been some discussion around whether they should with no conclusions
> being reached.

Exactly.

Will? Catalin? Any comments on this?

-- 
Ezequiel Garc?a, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com