diff options
| author | Will Deacon <will.deacon@arm.com> | 2019-02-22 13:37:21 +0000 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2019-04-08 12:00:32 +0100 |
| commit | 49ca6462fc9e0f5a67cd96eeddd844efc3fb33b9 (patch) | |
| tree | e4e9054283eee93d05a3b371fc2fa7db4fa15d97 /arch/ia64/include/asm/io.h | |
| parent | 346e91ee090b07da8d15e36bc3169ddea6968713 (diff) | |
ia64/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
The mmiowb() macro is horribly difficult to use and drivers will continue
to work most of the time if they omit a call when it is required.
Rather than rely on driver authors getting this right, push mmiowb() into
arch_spin_unlock() for ia64. If this is deemed to be a performance issue,
a subsequent optimisation could make use of ARCH_HAS_MMIOWB to elide
the barrier in cases where no I/O writes were performed inside the
critical section.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/ia64/include/asm/io.h')
| -rw-r--r-- | arch/ia64/include/asm/io.h | 17 |
1 files changed, 0 insertions, 17 deletions
diff --git a/arch/ia64/include/asm/io.h b/arch/ia64/include/asm/io.h index 1e6fef69bb01..a511d62d447a 100644 --- a/arch/ia64/include/asm/io.h +++ b/arch/ia64/include/asm/io.h @@ -113,20 +113,6 @@ extern int valid_mmap_phys_addr_range (unsigned long pfn, size_t count); */ #define __ia64_mf_a() ia64_mfa() -/** - * ___ia64_mmiowb - I/O write barrier - * - * Ensure ordering of I/O space writes. This will make sure that writes - * following the barrier will arrive after all previous writes. For most - * ia64 platforms, this is a simple 'mf.a' instruction. - * - * See Documentation/driver-api/device-io.rst for more information. - */ -static inline void ___ia64_mmiowb(void) -{ - ia64_mfa(); -} - static inline void* __ia64_mk_io_addr (unsigned long port) { @@ -161,7 +147,6 @@ __ia64_mk_io_addr (unsigned long port) #define __ia64_writew ___ia64_writew #define __ia64_writel ___ia64_writel #define __ia64_writeq ___ia64_writeq -#define __ia64_mmiowb ___ia64_mmiowb /* * For the in/out routines, we need to do "mf.a" _after_ doing the I/O access to ensure @@ -296,7 +281,6 @@ __outsl (unsigned long port, const void *src, unsigned long count) #define __outb platform_outb #define __outw platform_outw #define __outl platform_outl -#define __mmiowb platform_mmiowb #define inb(p) __inb(p) #define inw(p) __inw(p) @@ -310,7 +294,6 @@ __outsl (unsigned long port, const void *src, unsigned long count) #define outsb(p,s,c) __outsb(p,s,c) #define outsw(p,s,c) __outsw(p,s,c) #define outsl(p,s,c) __outsl(p,s,c) -#define mmiowb() __mmiowb() /* * The address passed to these functions are ioremap()ped already. |