[PATCH v3] ARM: supplementing IO accessors with 64 bit capability

From: mathieu . poirier
Date: Mon Oct 27 2014 - 11:39:21 EST


From: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>

Some drivers on ARMv7 need 64 bit read and writes.

Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Acked-by: Nicolas Pitre <nico@xxxxxxxxxx>
---
Change for v3:
- Bumped architecture version from 5 to 6

arch/arm/include/asm/io.h | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 1805674..b755776 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -118,6 +118,24 @@ static inline u32 __raw_readl(const volatile void __iomem *addr)
return val;
}

+#if __LINUX_ARM_ARCH__ >= 6
+static inline void __raw_writeq(u64 val, volatile void __iomem *addr)
+{
+ asm volatile("strd %1, %0"
+ : "+Qo" (*(volatile u64 __force *)addr)
+ : "r" (val));
+}
+
+static inline u64 __raw_readq(const volatile void __iomem *addr)
+{
+ u64 val;
+ asm volatile("ldrd %1, %0"
+ : "+Qo" (*(volatile u64 __force *)addr),
+ "=r" (val));
+ return val;
+}
+#endif
+
/*
* Architecture ioremap implementation.
*/
@@ -306,10 +324,17 @@ extern void _memset_io(volatile void __iomem *, int, size_t);
__raw_readw(c)); __r; })
#define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
__raw_readl(c)); __r; })
+#if __LINUX_ARM_ARCH__ >= 6
+#define readq_relaxed(c) ({ u64 __r = le64_to_cpu((__force __le64) \
+ __raw_readq(c)); __r; })
+#endif

#define writeb_relaxed(v,c) __raw_writeb(v,c)
#define writew_relaxed(v,c) __raw_writew((__force u16) cpu_to_le16(v),c)
#define writel_relaxed(v,c) __raw_writel((__force u32) cpu_to_le32(v),c)
+#if __LINUX_ARM_ARCH__ >= 6
+#define writeq_relaxed(v,c) __raw_writeq((__force u64) cpu_to_le64(v),c)
+#endif

#define readb(c) ({ u8 __v = readb_relaxed(c); __iormb(); __v; })
#define readw(c) ({ u16 __v = readw_relaxed(c); __iormb(); __v; })
--
1.9.1

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