[PATCH v3 1/8] asm-generic/io.h: allow barriers in io{read,write}{16,32}be

[PATCH v3 1/8] asm-generic/io.h: allow barriers in io{read,write}{16,32}be

[Horia Geantă]

While reviewing the addition of io{read,write}64be accessors, Arnd

-finds a potential problem:
"If an architecture overrides readq/writeq to have barriers but does
not override ioread64be/iowrite64be, this will lack the barriers and
behave differently from the little-endian version. I think the only
affected architecture is ARC, since ARM and ARM64 both override the
big-endian accessors to have the correct barriers, and all others
don't use barriers at all."

-suggests a fix for the same problem in existing code (16/32-bit
accessors); the fix leads "to a double-swap on architectures that
don't override the io{read,write}{16,32}be accessors, but it will
work correctly on all architectures without them having to override
these accessors."

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
---
 include/asm-generic/io.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index eed3bbe88c8a..b79fb2c248a1 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -613,7 +613,7 @@ static inline void iowrite32(u32 value, volatile void __iomem *addr)
 #define ioread16be ioread16be
 static inline u16 ioread16be(const volatile void __iomem *addr)
 {
-	return __be16_to_cpu(__raw_readw(addr));
+	return swab16(readw(addr));
 }
 #endif
 
@@ -621,7 +621,7 @@ static inline u16 ioread16be(const volatile void __iomem *addr)
 #define ioread32be ioread32be
 static inline u32 ioread32be(const volatile void __iomem *addr)
 {
-	return __be32_to_cpu(__raw_readl(addr));
+	return swab32(readl(addr));
 }
 #endif
 
@@ -629,7 +629,7 @@ static inline u32 ioread32be(const volatile void __iomem *addr)
 #define iowrite16be iowrite16be
 static inline void iowrite16be(u16 value, void volatile __iomem *addr)
 {
-	__raw_writew(__cpu_to_be16(value), addr);
+	writew(swab16(value), addr);
 }
 #endif
 
@@ -637,7 +637,7 @@ static inline void iowrite16be(u16 value, void volatile __iomem *addr)
 #define iowrite32be iowrite32be
 static inline void iowrite32be(u32 value, volatile void __iomem *addr)
 {
-	__raw_writel(__cpu_to_be32(value), addr);
+	writel(swab32(value), addr);
 }
 #endif
 
-- 
2.4.4

[PATCH v3 1/8] asm-generic/io.h: allow barriers in io{read,write}{16,32}be

[Horia Geantă]

While reviewing the addition of io{read,write}64be accessors, Arnd

-finds a potential problem:
"If an architecture overrides readq/writeq to have barriers but does
not override ioread64be/iowrite64be, this will lack the barriers and
behave differently from the little-endian version. I think the only
affected architecture is ARC, since ARM and ARM64 both override the
big-endian accessors to have the correct barriers, and all others
don't use barriers at all."

-suggests a fix for the same problem in existing code (16/32-bit
accessors); the fix leads "to a double-swap on architectures that
don't override the io{read,write}{16,32}be accessors, but it will
work correctly on all architectures without them having to override
these accessors."

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
---
 include/asm-generic/io.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index eed3bbe88c8a..b79fb2c248a1 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -613,7 +613,7 @@ static inline void iowrite32(u32 value, volatile void __iomem *addr)
 #define ioread16be ioread16be
 static inline u16 ioread16be(const volatile void __iomem *addr)
 {
-	return __be16_to_cpu(__raw_readw(addr));
+	return swab16(readw(addr));
 }
 #endif
 
@@ -621,7 +621,7 @@ static inline u16 ioread16be(const volatile void __iomem *addr)
 #define ioread32be ioread32be
 static inline u32 ioread32be(const volatile void __iomem *addr)
 {
-	return __be32_to_cpu(__raw_readl(addr));
+	return swab32(readl(addr));
 }
 #endif
 
@@ -629,7 +629,7 @@ static inline u32 ioread32be(const volatile void __iomem *addr)
 #define iowrite16be iowrite16be
 static inline void iowrite16be(u16 value, void volatile __iomem *addr)
 {
-	__raw_writew(__cpu_to_be16(value), addr);
+	writew(swab16(value), addr);
 }
 #endif
 
@@ -637,7 +637,7 @@ static inline void iowrite16be(u16 value, void volatile __iomem *addr)
 #define iowrite32be iowrite32be
 static inline void iowrite32be(u32 value, volatile void __iomem *addr)
 {
-	__raw_writel(__cpu_to_be32(value), addr);
+	writel(swab32(value), addr);
 }
 #endif
 
-- 
2.4.4

[PATCH v3 2/8] asm-generic/io.h: add io{read,write}64 accessors

[Horia Geantă]

This will allow device drivers to consistently use io{read,write}XX
also for 64-bit accesses.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
---
 include/asm-generic/io.h    | 63 +++++++++++++++++++++++++++++++++++++++++++++
 include/asm-generic/iomap.h |  8 ++++++
 2 files changed, 71 insertions(+)

diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index b79fb2c248a1..2af6ea95762d 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -585,6 +585,16 @@ static inline u32 ioread32(const volatile void __iomem *addr)
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef ioread64
+#define ioread64 ioread64
+static inline u64 ioread64(const volatile void __iomem *addr)
+{
+	return readq(addr);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef iowrite8
 #define iowrite8 iowrite8
 static inline void iowrite8(u8 value, volatile void __iomem *addr)
@@ -609,6 +619,16 @@ static inline void iowrite32(u32 value, volatile void __iomem *addr)
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef iowrite64
+#define iowrite64 iowrite64
+static inline void iowrite64(u64 value, volatile void __iomem *addr)
+{
+	writeq(value, addr);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef ioread16be
 #define ioread16be ioread16be
 static inline u16 ioread16be(const volatile void __iomem *addr)
@@ -625,6 +645,16 @@ static inline u32 ioread32be(const volatile void __iomem *addr)
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef ioread64be
+#define ioread64be ioread64be
+static inline u64 ioread64be(const volatile void __iomem *addr)
+{
+	return swab64(readq(addr));
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef iowrite16be
 #define iowrite16be iowrite16be
 static inline void iowrite16be(u16 value, void volatile __iomem *addr)
@@ -641,6 +671,16 @@ static inline void iowrite32be(u32 value, volatile void __iomem *addr)
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef iowrite64be
+#define iowrite64be iowrite64be
+static inline void iowrite64be(u64 value, volatile void __iomem *addr)
+{
+	writeq(swab64(value), addr);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef ioread8_rep
 #define ioread8_rep ioread8_rep
 static inline void ioread8_rep(const volatile void __iomem *addr, void *buffer,
@@ -668,6 +708,17 @@ static inline void ioread32_rep(const volatile void __iomem *addr,
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef ioread64_rep
+#define ioread64_rep ioread64_rep
+static inline void ioread64_rep(const volatile void __iomem *addr,
+				void *buffer, unsigned int count)
+{
+	readsq(addr, buffer, count);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef iowrite8_rep
 #define iowrite8_rep iowrite8_rep
 static inline void iowrite8_rep(volatile void __iomem *addr,
@@ -697,6 +748,18 @@ static inline void iowrite32_rep(volatile void __iomem *addr,
 	writesl(addr, buffer, count);
 }
 #endif
+
+#ifdef CONFIG_64BIT
+#ifndef iowrite64_rep
+#define iowrite64_rep iowrite64_rep
+static inline void iowrite64_rep(volatile void __iomem *addr,
+				 const void *buffer,
+				 unsigned int count)
+{
+	writesq(addr, buffer, count);
+}
+#endif
+#endif /* CONFIG_64BIT */
 #endif /* CONFIG_GENERIC_IOMAP */
 
 #ifdef __KERNEL__
diff --git a/include/asm-generic/iomap.h b/include/asm-generic/iomap.h
index d8f8622fa044..650fede33c25 100644
--- a/include/asm-generic/iomap.h
+++ b/include/asm-generic/iomap.h
@@ -30,12 +30,20 @@ extern unsigned int ioread16(void __iomem *);
 extern unsigned int ioread16be(void __iomem *);
 extern unsigned int ioread32(void __iomem *);
 extern unsigned int ioread32be(void __iomem *);
+#ifdef CONFIG_64BIT
+extern u64 ioread64(void __iomem *);
+extern u64 ioread64be(void __iomem *);
+#endif
 
 extern void iowrite8(u8, void __iomem *);
 extern void iowrite16(u16, void __iomem *);
 extern void iowrite16be(u16, void __iomem *);
 extern void iowrite32(u32, void __iomem *);
 extern void iowrite32be(u32, void __iomem *);
+#ifdef CONFIG_64BIT
+extern void iowrite64(u64, void __iomem *);
+extern void iowrite64be(u64, void __iomem *);
+#endif
 
 /*
  * "string" versions of the above. Note that they
-- 
2.4.4

[PATCH v3 2/8] asm-generic/io.h: add io{read,write}64 accessors

[Horia Geantă]

This will allow device drivers to consistently use io{read,write}XX
also for 64-bit accesses.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
---
 include/asm-generic/io.h    | 63 +++++++++++++++++++++++++++++++++++++++++++++
 include/asm-generic/iomap.h |  8 ++++++
 2 files changed, 71 insertions(+)

diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index b79fb2c248a1..2af6ea95762d 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -585,6 +585,16 @@ static inline u32 ioread32(const volatile void __iomem *addr)
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef ioread64
+#define ioread64 ioread64
+static inline u64 ioread64(const volatile void __iomem *addr)
+{
+	return readq(addr);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef iowrite8
 #define iowrite8 iowrite8
 static inline void iowrite8(u8 value, volatile void __iomem *addr)
@@ -609,6 +619,16 @@ static inline void iowrite32(u32 value, volatile void __iomem *addr)
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef iowrite64
+#define iowrite64 iowrite64
+static inline void iowrite64(u64 value, volatile void __iomem *addr)
+{
+	writeq(value, addr);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef ioread16be
 #define ioread16be ioread16be
 static inline u16 ioread16be(const volatile void __iomem *addr)
@@ -625,6 +645,16 @@ static inline u32 ioread32be(const volatile void __iomem *addr)
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef ioread64be
+#define ioread64be ioread64be
+static inline u64 ioread64be(const volatile void __iomem *addr)
+{
+	return swab64(readq(addr));
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef iowrite16be
 #define iowrite16be iowrite16be
 static inline void iowrite16be(u16 value, void volatile __iomem *addr)
@@ -641,6 +671,16 @@ static inline void iowrite32be(u32 value, volatile void __iomem *addr)
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef iowrite64be
+#define iowrite64be iowrite64be
+static inline void iowrite64be(u64 value, volatile void __iomem *addr)
+{
+	writeq(swab64(value), addr);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef ioread8_rep
 #define ioread8_rep ioread8_rep
 static inline void ioread8_rep(const volatile void __iomem *addr, void *buffer,
@@ -668,6 +708,17 @@ static inline void ioread32_rep(const volatile void __iomem *addr,
 }
 #endif
 
+#ifdef CONFIG_64BIT
+#ifndef ioread64_rep
+#define ioread64_rep ioread64_rep
+static inline void ioread64_rep(const volatile void __iomem *addr,
+				void *buffer, unsigned int count)
+{
+	readsq(addr, buffer, count);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
 #ifndef iowrite8_rep
 #define iowrite8_rep iowrite8_rep
 static inline void iowrite8_rep(volatile void __iomem *addr,
@@ -697,6 +748,18 @@ static inline void iowrite32_rep(volatile void __iomem *addr,
 	writesl(addr, buffer, count);
 }
 #endif
+
+#ifdef CONFIG_64BIT
+#ifndef iowrite64_rep
+#define iowrite64_rep iowrite64_rep
+static inline void iowrite64_rep(volatile void __iomem *addr,
+				 const void *buffer,
+				 unsigned int count)
+{
+	writesq(addr, buffer, count);
+}
+#endif
+#endif /* CONFIG_64BIT */
 #endif /* CONFIG_GENERIC_IOMAP */
 
 #ifdef __KERNEL__
diff --git a/include/asm-generic/iomap.h b/include/asm-generic/iomap.h
index d8f8622fa044..650fede33c25 100644
--- a/include/asm-generic/iomap.h
+++ b/include/asm-generic/iomap.h
@@ -30,12 +30,20 @@ extern unsigned int ioread16(void __iomem *);
 extern unsigned int ioread16be(void __iomem *);
 extern unsigned int ioread32(void __iomem *);
 extern unsigned int ioread32be(void __iomem *);
+#ifdef CONFIG_64BIT
+extern u64 ioread64(void __iomem *);
+extern u64 ioread64be(void __iomem *);
+#endif
 
 extern void iowrite8(u8, void __iomem *);
 extern void iowrite16(u16, void __iomem *);
 extern void iowrite16be(u16, void __iomem *);
 extern void iowrite32(u32, void __iomem *);
 extern void iowrite32be(u32, void __iomem *);
+#ifdef CONFIG_64BIT
+extern void iowrite64(u64, void __iomem *);
+extern void iowrite64be(u64, void __iomem *);
+#endif
 
 /*
  * "string" versions of the above. Note that they
-- 
2.4.4