1. This patch add required __iormb and __iowmb to io.h.
This also fix some misbehavior to periphal drivers.
This io.h has been fixed with referencing arm/include/asm/io.h.
2. This patch replaced macro writeb and readb into inline function.
Signed-off-by: Macpaul Lin <macpaul@andestech.com>
Add generic header files support for nds32 architecture.
Cache, ptregs, data type and other definitions are included.
Signed-off-by: Macpaul Lin <macpaul@andestech.com>