io.h

一个完整的GUI界面OS,单盘启动 实现了多线程、FAT32文件读写

//------------------------------------------------------------------
//
//
//         I/O  端口操作 模块 
//
//
//
//
//
//
//
//-------------------------------------------------------------------

#ifndef IO_H
#define IO_H
 
//------------------------------------------------------------------
//
//  向端口发送一个字 
//
//
//
//------------------------------------------------------------------
#define outb(value,port) \
__asm__ ("outb %%al,%%dx": :"a" (value),"d" (port))


//------------------------------------------------------------------
//
//  从端口输入一个字 
//
//
//
//------------------------------------------------------------------
#define inb(port) ({ \
unsigned char _v; \
__asm__ volatile ("inb %%dx,%%al":"=a" (_v):"d" (port)); \
_v; \
})


//------------------------------------------------------------------
//
//  向端口发送一个字 （带延迟） 
//
//
//
//------------------------------------------------------------------
#define outb_p(value,port) \
__asm__ ("outb %%al,%%dx\n" \
		"\tjmp 1f\n" \
		"1:\tjmp 1f\n" \
		"1:": :"a" (value),"d" (port))


//------------------------------------------------------------------
//
//  向端口发送一个字 （带延迟） 
//
//
//
//------------------------------------------------------------------
#define inb_p(port) ({ \
unsigned char _v; \
__asm__ volatile ("inb %%dx,%%al\n" \
	"\tjmp 1f\n" \
	"1:\tjmp 1f\n" \
	"1:":"=a" (_v):"d" (port)); \
_v; \
})


//--------------------------------------------------------------------------------------------------------------------------
//
//  读取 CMOS 端口
//
//--------------------------------------------------------------------------------------------------------------------------
extern __inline unsigned char ReadCmos(int reg)
{
	outb(reg,0x70);
	return (unsigned char) inb(0x71);
}

//--------------------------------------------------------------------------------------------------------------------------
//
//  IO设备延迟
//
//--------------------------------------------------------------------------------------------------------------------------
#define io_wait()   inb(0x80)

//--------------------------------------------------------------------------------------------------------------------------
//
//  核心延迟
//
//--------------------------------------------------------------------------------------------------------------------------
#define kernelDelay()  \
  __asm__ __volatile__ ("pushal \n\t"\
			"mov $0x3F6, %dx \n\t" \
			"inb %dx, %al \n\t"    \
			"inb %dx, %al \n\t"    \
			"inb %dx, %al \n\t"    \
			"inb %dx, %al \n\t"    \
			"popal")

//--------------------------------------------------------------------------------------------------------------------------
//
//  保存标志位寄存器信息
//
//--------------------------------------------------------------------------------------------------------------------------
static __inline unsigned save_eflags(unsigned *flags)
{
	unsigned ret_val;

	__asm__ __volatile__("pushfl\n"
		"popl %0\n"
		"cli"
		: "=a"(ret_val)
		:);
		*flags = ret_val;

	return ret_val;
}
			
//--------------------------------------------------------------------------------------------------------------------------
//
//  恢复标志位寄存器信息
//
//--------------------------------------------------------------------------------------------------------------------------
static __inline void restore_eflags(unsigned flags)
{
	__asm__ __volatile__("pushl %0\n"
		"popfl"
		:: "m"(flags));
}

#endif