#include <linux/string.h> #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 rep_movs(void *to, const void *from, size_t n) { unsigned long d0, d1, d2; asm volatile("rep ; movsl\n\t" "testb $2,%b4\n\t" "je 1f\n\t" "movsw\n" "1:\ttestb $1,%b4\n\t" "je 2f\n\t" "movsb\n" "2:" : "=&c" (d0), "=&D" (d1), "=&S" (d2) : "0" (n / 4), "q" (n), "1" ((long)to), "2" ((long)from) : "memory"); } void memcpy_fromio(void *to, const volatile void __iomem *from, size_t 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) { 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); void memset_io(volatile void __iomem *a, int b, size_t c) { /* * TODO: memset can mangle the IO patterns quite a bit. * perhaps it would be better to use a dumb one: */ memset((void *)a, b, c); } EXPORT_SYMBOL(memset_io); |