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Diffstat (limited to 'arch/x86/lib/iomem.c')
-rw-r--r--arch/x86/lib/iomem.c33
1 files changed, 30 insertions, 3 deletions
diff --git a/arch/x86/lib/iomem.c b/arch/x86/lib/iomem.c
index 66894675f3c8..df50451d94ef 100644
--- a/arch/x86/lib/iomem.c
+++ b/arch/x86/lib/iomem.c
@@ -2,8 +2,11 @@
#include <linux/module.h>
#include <linux/io.h>
+#define movs(type,to,from) \
+ asm volatile("movs" type:"=&D" (to), "=&S" (from):"0" (to), "1" (from):"memory")
+
/* Originally from i386/string.h */
-static __always_inline void __iomem_memcpy(void *to, const void *from, size_t n)
+static __always_inline void rep_movs(void *to, const void *from, size_t n)
{
unsigned long d0, d1, d2;
asm volatile("rep ; movsl\n\t"
@@ -21,13 +24,37 @@ static __always_inline void __iomem_memcpy(void *to, const void *from, size_t n)
void memcpy_fromio(void *to, const volatile void __iomem *from, size_t n)
{
- __iomem_memcpy(to, (const void *)from, n);
+ if (unlikely(!n))
+ return;
+
+ /* Align any unaligned source IO */
+ if (unlikely(1 & (unsigned long)from)) {
+ movs("b", to, from);
+ n--;
+ }
+ if (n > 1 && unlikely(2 & (unsigned long)from)) {
+ movs("w", to, from);
+ n-=2;
+ }
+ rep_movs(to, (const void *)from, n);
}
EXPORT_SYMBOL(memcpy_fromio);
void memcpy_toio(volatile void __iomem *to, const void *from, size_t n)
{
- __iomem_memcpy((void *)to, (const void *) from, n);
+ if (unlikely(!n))
+ return;
+
+ /* Align any unaligned destination IO */
+ if (unlikely(1 & (unsigned long)to)) {
+ movs("b", to, from);
+ n--;
+ }
+ if (n > 1 && unlikely(2 & (unsigned long)to)) {
+ movs("w", to, from);
+ n-=2;
+ }
+ rep_movs((void *)to, (const void *) from, n);
}
EXPORT_SYMBOL(memcpy_toio);