[2/2] arm64: io: Hook up __io_par() for inX() ordering
diff mbox series

Message ID 20190211174544.4302-3-will.deacon@arm.com
State Superseded
Headers show
Series
  • Ensure inX() is ordered wrt delay() routines
Related show

Commit Message

Will Deacon Feb. 11, 2019, 5:45 p.m. UTC
Ensure that inX() provides the same ordering guarantees as readX()
by hooking up __io_par() so that it maps directly to __iormb().

Reported-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/include/asm/io.h | 1 +
 1 file changed, 1 insertion(+)

Comments

Geert Uytterhoeven Feb. 12, 2019, 10:42 a.m. UTC | #1
Hi Will,

On Mon, Feb 11, 2019 at 9:34 PM Will Deacon <will.deacon@arm.com> wrote:
> Ensure that inX() provides the same ordering guarantees as readX()
> by hooking up __io_par() so that it maps directly to __iormb().
>
> Reported-by: Andrew Murray <andrew.murray@arm.com>
> Signed-off-by: Will Deacon <will.deacon@arm.com>

Thanks for your patch!

> --- a/arch/arm64/include/asm/io.h
> +++ b/arch/arm64/include/asm/io.h
> @@ -121,6 +121,7 @@ static inline u64 __raw_readq(const volatile void __iomem *addr)
>                      : "memory");                                       \
>  })
>
> +#define __io_par               __iormb

I think it makes sense to make the parameter passing explicit, for
documentation purposes:

    #define __io_par(v)        __iormb(v)

>  #define __iowmb()              wmb()
>
>  #define mmiowb()               do { } while (0)

Gr{oetje,eeting}s,

                        Geert
Will Deacon Feb. 13, 2019, 5:25 p.m. UTC | #2
On Tue, Feb 12, 2019 at 11:42:44AM +0100, Geert Uytterhoeven wrote:
> On Mon, Feb 11, 2019 at 9:34 PM Will Deacon <will.deacon@arm.com> wrote:
> > Ensure that inX() provides the same ordering guarantees as readX()
> > by hooking up __io_par() so that it maps directly to __iormb().
> >
> > Reported-by: Andrew Murray <andrew.murray@arm.com>
> > Signed-off-by: Will Deacon <will.deacon@arm.com>
> 
> Thanks for your patch!
> 
> > --- a/arch/arm64/include/asm/io.h
> > +++ b/arch/arm64/include/asm/io.h
> > @@ -121,6 +121,7 @@ static inline u64 __raw_readq(const volatile void __iomem *addr)
> >                      : "memory");                                       \
> >  })
> >
> > +#define __io_par               __iormb
> 
> I think it makes sense to make the parameter passing explicit, for
> documentation purposes:
> 
>     #define __io_par(v)        __iormb(v)

Thanks, I'll make that change for v2.

Will

Patch
diff mbox series

diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h
index ee723835c1f4..2985febe63ec 100644
--- a/arch/arm64/include/asm/io.h
+++ b/arch/arm64/include/asm/io.h
@@ -121,6 +121,7 @@  static inline u64 __raw_readq(const volatile void __iomem *addr)
 		     : "memory");					\
 })
 
+#define __io_par		__iormb
 #define __iowmb()		wmb()
 
 #define mmiowb()		do { } while (0)