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io-64-nonatomic: Add relaxed accessor variants

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Whilst commit 9439eb3ab9 ("asm-generic: io: implement relaxed
accessor macros as conditional wrappers") makes the *_relaxed forms of
I/O accessors universally available to drivers, in cases where writeq()
is implemented via the io-64-nonatomic helpers, writeq_relaxed() will
end up falling back to writel() regardless of whether writel_relaxed()
is available (identically for s/write/read/).

Add corresponding relaxed forms of the nonatomic helpers to delegate
to the equivalent 32-bit accessors as appropriate. We also need to fix
io.h to avoid defining default relaxed variants if the basic accessors
themselves don't exist.

CC: Christoph Hellwig <hch@lst.de>
CC: Darren Hart <dvhart@linux.intel.com>
CC: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Robin Murphy 2016-04-26 11:38:20 +01:00 committed by Will Deacon
parent f0cfffc48c
commit e511267bc2
3 changed files with 52 additions and 2 deletions
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4
include/asm-generic/io.h
View File

@ -191,7 +191,7 @@ static inline void writeq(u64 value, volatile void __iomem *addr)
#define readl_relaxed readl
#endif
#ifndef readq_relaxed
#if defined(readq) && !defined(readq_relaxed)
#define readq_relaxed readq
#endif
@ -207,7 +207,7 @@ static inline void writeq(u64 value, volatile void __iomem *addr)
#define writel_relaxed writel
#endif
#ifndef writeq_relaxed
#if defined(writeq) && !defined(writeq_relaxed)
#define writeq_relaxed writeq
#endif

25
include/linux/io-64-nonatomic-hi-lo.h
View File

@ -21,6 +21,23 @@ static inline void hi_lo_writeq(__u64 val, volatile void __iomem *addr)
writel(val, addr);
}
static inline __u64 hi_lo_readq_relaxed(const volatile void __iomem *addr)
{
const volatile u32 __iomem *p = addr;
u32 low, high;
high = readl_relaxed(p + 1);
low = readl_relaxed(p);
return low + ((u64)high << 32);
}
static inline void hi_lo_writeq_relaxed(__u64 val, volatile void __iomem *addr)
{
writel_relaxed(val >> 32, addr + 4);
writel_relaxed(val, addr);
}
#ifndef readq
#define readq hi_lo_readq
#endif
@ -29,4 +46,12 @@ static inline void hi_lo_writeq(__u64 val, volatile void __iomem *addr)
#define writeq hi_lo_writeq
#endif
#ifndef readq_relaxed
#define readq_relaxed hi_lo_readq_relaxed
#endif
#ifndef writeq_relaxed
#define writeq_relaxed hi_lo_writeq_relaxed
#endif
#endif /* _LINUX_IO_64_NONATOMIC_HI_LO_H_ */

25
include/linux/io-64-nonatomic-lo-hi.h
View File

@ -21,6 +21,23 @@ static inline void lo_hi_writeq(__u64 val, volatile void __iomem *addr)
writel(val >> 32, addr + 4);
}
static inline __u64 lo_hi_readq_relaxed(const volatile void __iomem *addr)
{
const volatile u32 __iomem *p = addr;
u32 low, high;
low = readl_relaxed(p);
high = readl_relaxed(p + 1);
return low + ((u64)high << 32);
}
static inline void lo_hi_writeq_relaxed(__u64 val, volatile void __iomem *addr)
{
writel_relaxed(val, addr);
writel_relaxed(val >> 32, addr + 4);
}
#ifndef readq
#define readq lo_hi_readq
#endif
@ -29,4 +46,12 @@ static inline void lo_hi_writeq(__u64 val, volatile void __iomem *addr)
#define writeq lo_hi_writeq
#endif
#ifndef readq_relaxed
#define readq_relaxed lo_hi_readq_relaxed
#endif
#ifndef writeq_relaxed
#define writeq_relaxed lo_hi_writeq_relaxed
#endif
#endif /* _LINUX_IO_64_NONATOMIC_LO_HI_H_ */