[PATCH v5 17/19] arm: Add IO accessors to avoid register-writeback

Andrew Jones
2014-06-11T14:02:05Z

From: Christoffer Dall <christoffer.dall@linaro.org>

Add IO accessor functions to the arm library functions to avoid
register-writeback IO accessors that are not yet supported by the
kernel.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Andrew Jones <drjones@redhat.com>
---
lib/arm/asm/io.h | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 57 insertions(+)

diff --git a/lib/arm/asm/io.h b/lib/arm/asm/io.h
index 51ec6e9aa2e99..1d0abb7d9f405 100644
--- a/lib/arm/asm/io.h
+++ b/lib/arm/asm/io.h
@@ -3,6 +3,9 @@
#include "libcflat.h"
#include "asm/barrier.h"

+#define __iomem
+#define __force
+
#define __bswap16 bswap16
static inline u16 bswap16(u16 val)
{
@@ -19,6 +22,60 @@ static inline u32 bswap32(u32 val)
return ret;
}

+#define __raw_readb __raw_readb
+static inline u8 __raw_readb(const volatile void __iomem *addr)
+{
+ u8 val;
+ asm volatile("ldrb %1, %0"
+ : "+Qo" (*(volatile u8 __force *)addr),
+ "=r" (val));
+ return val;
+}
+
+#define __raw_readw __raw_readw
+static inline u16 __raw_readw(const volatile void __iomem *addr)
+{
+ u16 val;
+ asm volatile("ldrh %1, %0"
+ : "+Q" (*(volatile u16 __force *)addr),
+ "=r" (val));
+ return val;
+}
+
+#define __raw_readl __raw_readl
+static inline u32 __raw_readl(const volatile void __iomem *addr)
+{
+ u32 val;
+ asm volatile("ldr %1, %0"
+ : "+Qo" (*(volatile u32 __force *)addr),
+ "=r" (val));
+ return val;
+}
+
+#define __raw_writeb __raw_writeb
+static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
+{
+ asm volatile("strb %1, %0"
+ : "+Qo" (*(volatile u8 __force *)addr)
+ : "r" (val));
+}
+
+#define __raw_writew __raw_writew
+static inline void __raw_writew(u16 val, volatile void __iomem *addr)
+{
+ asm volatile("strh %1, %0"
+ : "+Q" (*(volatile u16 __force *)addr)
+ : "r" (val));
+}
+
+#define __raw_writel __raw_writel
+static inline void __raw_writel(u32 val, volatile void __iomem *addr)
+{
+ asm volatile("str %1, %0"
+ : "+Qo" (*(volatile u32 __force *)addr)
+ : "r" (val));
+}
+
#include "asm-generic/io.h"

#endif /* _ASMARM_IO_H_ */
--
1.9.3