io.h

来自「This a naive implementation of BOOTP/TFT」· C头文件 代码 · 共 30 行

#ifndef _IO_H_
#define _IO_H_

/*
 * readX/writeX() are used to access memory mapped io devices. 
 * On the m68k architecture, we just read/write the memory location directly.
 */

#define readb(addr) (*(volatile unsigned char *) (addr))
#define readw(addr) (*(volatile unsigned short *) (addr))
#define readl(addr) (*(volatile unsigned int *) (addr))

#define writeb(b,addr) (void)((*(volatile unsigned char *) (addr)) = (b))
#define writew(w,addr) (void)((*(volatile unsigned short *) (addr)) = (w))
#define writel(l,addr) (void)((*(volatile unsigned int *) (addr)) = (l))

#define orb(b,addr) (void)((*(volatile unsigned char *) (addr)) |= (b))
#define orw(w,addr) (void)((*(volatile unsigned short *) (addr)) |= (w))
#define orl(l,addr) (void)((*(volatile unsigned int *) (addr)) |= (l))

#define andb(b,addr) (void)((*(volatile unsigned char *) (addr)) &= (b))
#define andw(w,addr) (void)((*(volatile unsigned short *) (addr)) &= (w))
#define andl(l,addr) (void)((*(volatile unsigned int *) (addr)) &= (l))

#define outb(b,addr) writeb(b,addr)
#define outw(w,addr) writew(w,addr)
#define outl(l,addr) writel(l,addr)

#endif /* _IO_H_ */