io.h

#define __arch_getb(a)			(*(volatile unsigned char *)(a))
#define __arch_getw(a)			(*(volatile unsigned short *)(a))
#define __arch_getl(a)			(*(volatile unsigned int *)(a))

#define __arch_putb(v,a)		(*(volatile unsigned char *)(a) = (v))
#define __arch_putw(v,a)		(*(volatile unsigned short *)(a) = (v))
#define __arch_putl(v,a)		(*(volatile unsigned int *)(a) = (v))


#define dmb()		__asm__ __volatile__ ("" : : : "memory")
#define __iormb()	dmb()
#define __iowmb()	dmb()

#define writeb(v,c)	({ u8  __v = v; __iowmb(); __arch_putb(__v,c); __v; })
#define writew(v,c)	({ u16 __v = v; __iowmb(); __arch_putw(__v,c); __v; })
#define writel(v,c)	({ u32 __v = v; __iowmb(); __arch_putl(__v,c); __v; })

#define readb(c)	({ u8  __v = __arch_getb(c); __iormb(); __v; })
#define readw(c)	({ u16 __v = __arch_getw(c); __iormb(); __v; })
#define readl(c)	({ u32 __v = __arch_getl(c); __iormb(); __v; })