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-rw-r--r--arch/arc/include/asm/bitops.h15
-rw-r--r--arch/arc/include/asm/io.h18
2 files changed, 13 insertions, 20 deletions
diff --git a/arch/arc/include/asm/bitops.h b/arch/arc/include/asm/bitops.h
index 57c1f3384..0352fb8d2 100644
--- a/arch/arc/include/asm/bitops.h
+++ b/arch/arc/include/asm/bitops.h
@@ -35,21 +35,6 @@ static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
\
m += nr >> 5; \
\
- /* \
- * ARC ISA micro-optimization: \
- * \
- * Instructions dealing with bitpos only consider lower 5 bits \
- * e.g (x << 33) is handled like (x << 1) by ASL instruction \
- * (mem pointer still needs adjustment to point to next word) \
- * \
- * Hence the masking to clamp @nr arg can be elided in general. \
- * \
- * However if @nr is a constant (above assumed in a register), \
- * and greater than 31, gcc can optimize away (x << 33) to 0, \
- * as overflow, given the 32-bit ISA. Thus masking needs to be \
- * done for const @nr, but no code is generated due to gcc \
- * const prop. \
- */ \
nr &= 0x1f; \
\
__asm__ __volatile__( \
diff --git a/arch/arc/include/asm/io.h b/arch/arc/include/asm/io.h
index 694ece8a0..27b17adea 100644
--- a/arch/arc/include/asm/io.h
+++ b/arch/arc/include/asm/io.h
@@ -129,15 +129,23 @@ static inline void __raw_writel(u32 w, volatile void __iomem *addr)
#define writel(v,c) ({ __iowmb(); writel_relaxed(v,c); })
/*
- * Relaxed API for drivers which can handle any ordering themselves
+ * Relaxed API for drivers which can handle barrier ordering themselves
+ *
+ * Also these are defined to perform little endian accesses.
+ * To provide the typical device register semantics of fixed endian,
+ * swap the byte order for Big Endian
+ *
+ * http://lkml.kernel.org/r/201603100845.30602.arnd@arndb.de
*/
#define readb_relaxed(c) __raw_readb(c)
-#define readw_relaxed(c) __raw_readw(c)
-#define readl_relaxed(c) __raw_readl(c)
+#define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
+ __raw_readw(c)); __r; })
+#define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
+ __raw_readl(c)); __r; })
#define writeb_relaxed(v,c) __raw_writeb(v,c)
-#define writew_relaxed(v,c) __raw_writew(v,c)
-#define writel_relaxed(v,c) __raw_writel(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)
#include <asm-generic/io.h>