I feel like something "different" is happening when executing the io.h->out_8
function. Could somebody help me understand this op code
v2013.01.01 Code:
extern inline void out_8(volatile unsigned char __iomem *addr, u8 val)
{
__asm__ __volatile__("sync;\n"
"stb%U0%X0 %1,%0;\n"
: "=m" (*addr)
: "r" (val));
}
Old 1.7.02 Code:
extern inline void out_8(volatile unsigned char __iomem *addr, int val)
{
__asm__ __volatile__("stb%U0%X0 %1,%0; eieio" : "=m" (*addr) : "r"
(val));
}
So I understand the sync op code but what is going on here? Could someone
with some expertise explain "stb%U0%X0 %1,%0" and "stb%U0%X0 %1,%0; eieio".
Thanks!
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