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authorArnd Bergmann <arnd@arndb.de>2014-11-11 19:55:45 +0100
committerArnd Bergmann <arnd@arndb.de>2014-11-11 19:55:45 +0100
commit1c8d29696f0d79902962526d6c54ebfeb842c61d (patch)
tree047caddef4ee91e42002bc1234d273c6fbc54967
parentARM: sa11x0: Use void __iomem * in MMIO accessors (diff)
parentdocumentation: memory-barriers: clarify relaxed io accessor semantics (diff)
downloadlinux-1c8d29696f0d79902962526d6c54ebfeb842c61d.tar.xz
linux-1c8d29696f0d79902962526d6c54ebfeb842c61d.zip
Merge branch 'io' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into asm-generic
* 'io' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux: documentation: memory-barriers: clarify relaxed io accessor semantics x86: io: implement dummy relaxed accessor macros for writes tile: io: implement dummy relaxed accessor macros for writes sparc: io: implement dummy relaxed accessor macros for writes powerpc: io: implement dummy relaxed accessor macros for writes parisc: io: implement dummy relaxed accessor macros for writes mn10300: io: implement dummy relaxed accessor macros for writes m68k: io: implement dummy relaxed accessor macros for writes m32r: io: implement dummy relaxed accessor macros for writes ia64: io: implement dummy relaxed accessor macros for writes cris: io: implement dummy relaxed accessor macros for writes frv: io: implement dummy relaxed accessor macros for writes xtensa: io: remove dummy relaxed accessor macros for reads s390: io: remove dummy relaxed accessor macros for reads microblaze: io: remove dummy relaxed accessor macros asm-generic: io: implement relaxed accessor macros as conditional wrappers Conflicts: include/asm-generic/io.h Signed-off-by: Arnd Bergmann <arnd@arndb.de>
-rw-r--r--Documentation/memory-barriers.txt13
-rw-r--r--arch/cris/include/asm/io.h3
-rw-r--r--arch/frv/include/asm/io.h3
-rw-r--r--arch/ia64/include/asm/io.h4
-rw-r--r--arch/m32r/include/asm/io.h3
-rw-r--r--arch/m68k/include/asm/io.h8
-rw-r--r--arch/m68k/include/asm/io_no.h4
-rw-r--r--arch/microblaze/include/asm/io.h8
-rw-r--r--arch/mn10300/include/asm/io.h4
-rw-r--r--arch/parisc/include/asm/io.h12
-rw-r--r--arch/powerpc/include/asm/io.h12
-rw-r--r--arch/s390/include/asm/io.h5
-rw-r--r--arch/sparc/include/asm/io.h9
-rw-r--r--arch/sparc/include/asm/io_32.h4
-rw-r--r--arch/sparc/include/asm/io_64.h8
-rw-r--r--arch/tile/include/asm/io.h4
-rw-r--r--arch/x86/include/asm/io.h4
-rw-r--r--arch/xtensa/include/asm/io.h7
-rw-r--r--include/asm-generic/io.h37
19 files changed, 106 insertions, 46 deletions
diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index 22a969cdd476..4af4cea8cff0 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -2465,10 +2465,15 @@ functions:
Please refer to the PCI specification for more information on interactions
between PCI transactions.
- (*) readX_relaxed()
-
- These are similar to readX(), but are not guaranteed to be ordered in any
- way. Be aware that there is no I/O read barrier available.
+ (*) readX_relaxed(), writeX_relaxed()
+
+ These are similar to readX() and writeX(), but provide weaker memory
+ ordering guarantees. Specifically, they do not guarantee ordering with
+ respect to normal memory accesses (e.g. DMA buffers) nor do they guarantee
+ ordering with respect to LOCK or UNLOCK operations. If the latter is
+ required, an mmiowb() barrier can be used. Note that relaxed accesses to
+ the same peripheral are guaranteed to be ordered with respect to each
+ other.
(*) ioreadX(), iowriteX()
diff --git a/arch/cris/include/asm/io.h b/arch/cris/include/asm/io.h
index e59dba12ce94..752a3f45df60 100644
--- a/arch/cris/include/asm/io.h
+++ b/arch/cris/include/asm/io.h
@@ -112,6 +112,9 @@ static inline void writel(unsigned int b, volatile void __iomem *addr)
else
*(volatile unsigned int __force *) addr = b;
}
+#define writeb_relaxed(b, addr) writeb(b, addr)
+#define writew_relaxed(b, addr) writew(b, addr)
+#define writel_relaxed(b, addr) writel(b, addr)
#define __raw_writeb writeb
#define __raw_writew writew
#define __raw_writel writel
diff --git a/arch/frv/include/asm/io.h b/arch/frv/include/asm/io.h
index 8cb50a2fbcb2..99bb7efaf9b7 100644
--- a/arch/frv/include/asm/io.h
+++ b/arch/frv/include/asm/io.h
@@ -243,6 +243,9 @@ static inline void writel(uint32_t datum, volatile void __iomem *addr)
__flush_PCI_writes();
}
+#define writeb_relaxed writeb
+#define writew_relaxed writew
+#define writel_relaxed writel
/* Values for nocacheflag and cmode */
#define IOMAP_FULL_CACHING 0
diff --git a/arch/ia64/include/asm/io.h b/arch/ia64/include/asm/io.h
index bee0acd52f7e..80a7e34be009 100644
--- a/arch/ia64/include/asm/io.h
+++ b/arch/ia64/include/asm/io.h
@@ -393,6 +393,10 @@ __writeq (unsigned long val, volatile void __iomem *addr)
#define writew(v,a) __writew((v), (a))
#define writel(v,a) __writel((v), (a))
#define writeq(v,a) __writeq((v), (a))
+#define writeb_relaxed(v,a) __writeb((v), (a))
+#define writew_relaxed(v,a) __writew((v), (a))
+#define writel_relaxed(v,a) __writel((v), (a))
+#define writeq_relaxed(v,a) __writeq((v), (a))
#define __raw_writeb writeb
#define __raw_writew writew
#define __raw_writel writel
diff --git a/arch/m32r/include/asm/io.h b/arch/m32r/include/asm/io.h
index 4010f1fc5b65..6e7787f3dac7 100644
--- a/arch/m32r/include/asm/io.h
+++ b/arch/m32r/include/asm/io.h
@@ -161,6 +161,9 @@ static inline void _writel(unsigned long l, unsigned long addr)
#define __raw_writeb writeb
#define __raw_writew writew
#define __raw_writel writel
+#define writeb_relaxed writeb
+#define writew_relaxed writew
+#define writel_relaxed writel
#define ioread8 read
#define ioread16 readw
diff --git a/arch/m68k/include/asm/io.h b/arch/m68k/include/asm/io.h
index c70cc9155003..bccd5a914eb6 100644
--- a/arch/m68k/include/asm/io.h
+++ b/arch/m68k/include/asm/io.h
@@ -3,3 +3,11 @@
#else
#include <asm/io_mm.h>
#endif
+
+#define readb_relaxed(addr) readb(addr)
+#define readw_relaxed(addr) readw(addr)
+#define readl_relaxed(addr) readl(addr)
+
+#define writeb_relaxed(b, addr) writeb(b, addr)
+#define writew_relaxed(b, addr) writew(b, addr)
+#define writel_relaxed(b, addr) writel(b, addr)
diff --git a/arch/m68k/include/asm/io_no.h b/arch/m68k/include/asm/io_no.h
index be4b5a813ad4..a93c8cde4d38 100644
--- a/arch/m68k/include/asm/io_no.h
+++ b/arch/m68k/include/asm/io_no.h
@@ -40,10 +40,6 @@ static inline unsigned int _swapl(volatile unsigned long v)
#define readl(addr) \
({ unsigned int __v = (*(volatile unsigned int *) (addr)); __v; })
-#define readb_relaxed(addr) readb(addr)
-#define readw_relaxed(addr) readw(addr)
-#define readl_relaxed(addr) readl(addr)
-
#define writeb(b,addr) (void)((*(volatile unsigned char *) (addr)) = (b))
#define writew(b,addr) (void)((*(volatile unsigned short *) (addr)) = (b))
#define writel(b,addr) (void)((*(volatile unsigned int *) (addr)) = (b))
diff --git a/arch/microblaze/include/asm/io.h b/arch/microblaze/include/asm/io.h
index 433751b2a003..940f5fc1d1da 100644
--- a/arch/microblaze/include/asm/io.h
+++ b/arch/microblaze/include/asm/io.h
@@ -69,12 +69,4 @@ extern void __iomem *ioremap(phys_addr_t address, unsigned long size);
#include <asm-generic/io.h>
-#define readb_relaxed readb
-#define readw_relaxed readw
-#define readl_relaxed readl
-
-#define writeb_relaxed writeb
-#define writew_relaxed writew
-#define writel_relaxed writel
-
#endif /* _ASM_MICROBLAZE_IO_H */
diff --git a/arch/mn10300/include/asm/io.h b/arch/mn10300/include/asm/io.h
index e6ed0d897ccc..897ba3c12b32 100644
--- a/arch/mn10300/include/asm/io.h
+++ b/arch/mn10300/include/asm/io.h
@@ -67,6 +67,10 @@ static inline void writel(u32 b, volatile void __iomem *addr)
#define __raw_writew writew
#define __raw_writel writel
+#define writeb_relaxed writeb
+#define writew_relaxed writew
+#define writel_relaxed writel
+
/*****************************************************************************/
/*
* traditional input/output functions
diff --git a/arch/parisc/include/asm/io.h b/arch/parisc/include/asm/io.h
index 1f6d2ae7aba5..8cd0abf28ffb 100644
--- a/arch/parisc/include/asm/io.h
+++ b/arch/parisc/include/asm/io.h
@@ -217,10 +217,14 @@ static inline void writeq(unsigned long long q, volatile void __iomem *addr)
#define writel writel
#define writeq writeq
-#define readb_relaxed(addr) readb(addr)
-#define readw_relaxed(addr) readw(addr)
-#define readl_relaxed(addr) readl(addr)
-#define readq_relaxed(addr) readq(addr)
+#define readb_relaxed(addr) readb(addr)
+#define readw_relaxed(addr) readw(addr)
+#define readl_relaxed(addr) readl(addr)
+#define readq_relaxed(addr) readq(addr)
+#define writeb_relaxed(b, addr) writeb(b, addr)
+#define writew_relaxed(w, addr) writew(w, addr)
+#define writel_relaxed(l, addr) writel(l, addr)
+#define writeq_relaxed(q, addr) writeq(q, addr)
#define mmiowb() do { } while (0)
diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h
index 97d3869991ca..9eaf301ac952 100644
--- a/arch/powerpc/include/asm/io.h
+++ b/arch/powerpc/include/asm/io.h
@@ -617,10 +617,14 @@ static inline void name at \
/*
* We don't do relaxed operations yet, at least not with this semantic
*/
-#define readb_relaxed(addr) readb(addr)
-#define readw_relaxed(addr) readw(addr)
-#define readl_relaxed(addr) readl(addr)
-#define readq_relaxed(addr) readq(addr)
+#define readb_relaxed(addr) readb(addr)
+#define readw_relaxed(addr) readw(addr)
+#define readl_relaxed(addr) readl(addr)
+#define readq_relaxed(addr) readq(addr)
+#define writeb_relaxed(v, addr) writeb(v, addr)
+#define writew_relaxed(v, addr) writew(v, addr)
+#define writel_relaxed(v, addr) writel(v, addr)
+#define writeq_relaxed(v, addr) writeq(v, addr)
#ifdef CONFIG_PPC32
#define mmiowb()
diff --git a/arch/s390/include/asm/io.h b/arch/s390/include/asm/io.h
index d22c2eeae78f..6ad9013c67e7 100644
--- a/arch/s390/include/asm/io.h
+++ b/arch/s390/include/asm/io.h
@@ -61,11 +61,6 @@ static inline void iounmap(volatile void __iomem *addr)
#define __raw_writel zpci_write_u32
#define __raw_writeq zpci_write_u64
-#define readb_relaxed readb
-#define readw_relaxed readw
-#define readl_relaxed readl
-#define readq_relaxed readq
-
#endif /* CONFIG_PCI */
#include <asm-generic/io.h>
diff --git a/arch/sparc/include/asm/io.h b/arch/sparc/include/asm/io.h
index f6902cf3cbe9..493f22c4684f 100644
--- a/arch/sparc/include/asm/io.h
+++ b/arch/sparc/include/asm/io.h
@@ -10,6 +10,15 @@
* Defines used for both SPARC32 and SPARC64
*/
+/* Relaxed accessors for MMIO */
+#define readb_relaxed(__addr) readb(__addr)
+#define readw_relaxed(__addr) readw(__addr)
+#define readl_relaxed(__addr) readl(__addr)
+
+#define writeb_relaxed(__b, __addr) writeb(__b, __addr)
+#define writew_relaxed(__w, __addr) writew(__w, __addr)
+#define writel_relaxed(__l, __addr) writel(__l, __addr)
+
/* Big endian versions of memory read/write routines */
#define readb_be(__addr) __raw_readb(__addr)
#define readw_be(__addr) __raw_readw(__addr)
diff --git a/arch/sparc/include/asm/io_32.h b/arch/sparc/include/asm/io_32.h
index 9f532902627c..407ac14295f4 100644
--- a/arch/sparc/include/asm/io_32.h
+++ b/arch/sparc/include/asm/io_32.h
@@ -4,10 +4,6 @@
#include <linux/kernel.h>
#include <linux/ioport.h> /* struct resource */
-#define readb_relaxed(__addr) readb(__addr)
-#define readw_relaxed(__addr) readw(__addr)
-#define readl_relaxed(__addr) readl(__addr)
-
#define IO_SPACE_LIMIT 0xffffffff
#define memset_io(d,c,sz) _memset_io(d,c,sz)
diff --git a/arch/sparc/include/asm/io_64.h b/arch/sparc/include/asm/io_64.h
index 80b54b326d49..d50e6127325d 100644
--- a/arch/sparc/include/asm/io_64.h
+++ b/arch/sparc/include/asm/io_64.h
@@ -136,6 +136,7 @@ static inline u32 readl(const volatile void __iomem *addr)
}
#define readq readq
+#define readq_relaxed readq
static inline u64 readq(const volatile void __iomem *addr)
{ u64 ret;
@@ -175,6 +176,7 @@ static inline void writel(u32 l, volatile void __iomem *addr)
}
#define writeq writeq
+#define writeq_relaxed writeq
static inline void writeq(u64 q, volatile void __iomem *addr)
{
__asm__ __volatile__("stxa\t%r0, [%1] %2\t/* pci_writeq */"
@@ -183,7 +185,6 @@ static inline void writeq(u64 q, volatile void __iomem *addr)
: "memory");
}
-
#define inb inb
static inline u8 inb(unsigned long addr)
{
@@ -264,11 +265,6 @@ static inline void iowrite32_rep(void __iomem *port, const void *buf, unsigned l
outsl((unsigned long __force)port, buf, count);
}
-#define readb_relaxed(__addr) readb(__addr)
-#define readw_relaxed(__addr) readw(__addr)
-#define readl_relaxed(__addr) readl(__addr)
-#define readq_relaxed(__addr) readq(__addr)
-
/* Valid I/O Space regions are anywhere, because each PCI bus supported
* can live in an arbitrary area of the physical address range.
*/
diff --git a/arch/tile/include/asm/io.h b/arch/tile/include/asm/io.h
index 9fe434969fab..d372641054d9 100644
--- a/arch/tile/include/asm/io.h
+++ b/arch/tile/include/asm/io.h
@@ -241,6 +241,10 @@ static inline void writeq(u64 val, unsigned long addr)
#define readw_relaxed readw
#define readl_relaxed readl
#define readq_relaxed readq
+#define writeb_relaxed writeb
+#define writew_relaxed writew
+#define writel_relaxed writel
+#define writeq_relaxed writeq
#define ioread8 readb
#define ioread16 readw
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index ae2b593e7c6e..0cdbe6e81b45 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -74,6 +74,9 @@ build_mmio_write(__writel, "l", unsigned int, "r", )
#define __raw_readw __readw
#define __raw_readl __readl
+#define writeb_relaxed(v, a) __writeb(v, a)
+#define writew_relaxed(v, a) __writew(v, a)
+#define writel_relaxed(v, a) __writel(v, a)
#define __raw_writeb __writeb
#define __raw_writew __writew
#define __raw_writel __writel
@@ -86,6 +89,7 @@ build_mmio_read(readq, "q", unsigned long, "=r", :"memory")
build_mmio_write(writeq, "q", unsigned long, "r", :"memory")
#define readq_relaxed(a) readq(a)
+#define writeq_relaxed(v, a) writeq(v, a)
#define __raw_readq(a) readq(a)
#define __raw_writeq(val, addr) writeq(val, addr)
diff --git a/arch/xtensa/include/asm/io.h b/arch/xtensa/include/asm/io.h
index 74944207167e..fe1600a09438 100644
--- a/arch/xtensa/include/asm/io.h
+++ b/arch/xtensa/include/asm/io.h
@@ -74,13 +74,6 @@ static inline void iounmap(volatile void __iomem *addr)
#endif /* CONFIG_MMU */
-/*
- * Generic I/O
- */
-#define readb_relaxed readb
-#define readw_relaxed readw
-#define readl_relaxed readl
-
#endif /* __KERNEL__ */
#include <asm-generic/io.h>
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index 00483d769d86..9db042304df3 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -175,6 +175,43 @@ static inline void writeq(u64 value, volatile void __iomem *addr)
#endif /* CONFIG_64BIT */
/*
+ * {read,write}{b,w,l,q}_relaxed() are like the regular version, but
+ * are not guaranteed to provide ordering against spinlocks or memory
+ * accesses.
+ */
+#ifndef readb_relaxed
+#define readb_relaxed readb
+#endif
+
+#ifndef readw_relaxed
+#define readw_relaxed readw
+#endif
+
+#ifndef readl_relaxed
+#define readl_relaxed readl
+#endif
+
+#ifndef readq_relaxed
+#define readq_relaxed readq
+#endif
+
+#ifndef writeb_relaxed
+#define writeb_relaxed writeb
+#endif
+
+#ifndef writew_relaxed
+#define writew_relaxed writew
+#endif
+
+#ifndef writel_relaxed
+#define writel_relaxed writel
+#endif
+
+#ifndef writeq_relaxed
+#define writeq_relaxed writeq
+#endif
+
+/*
* {read,write}s{b,w,l,q}() repeatedly access the same memory address in
* native endianness in 8-, 16-, 32- or 64-bit chunks (@count times).
*/