i386.h

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/* i386.h */

#define	NBPG		4096


#define	NID		48
#define	NGD		 8

#define	IRQBASE		32	/* base ivec for IRQ0			*/

struct idt {
	unsigned short	igd_loffset;
	unsigned short	igd_segsel;
	unsigned int	igd_rsvd : 5;
	unsigned int	igd_mbz : 3;
	unsigned int	igd_type : 5;
	unsigned int	igd_dpl : 2;
	unsigned int	igd_present : 1;
	unsigned short	igd_hoffset;
};

#define	IGDT_TASK	 5	/* task gate IDT descriptor		*/
#define	IGDT_INTR	14	/* interrupt gate IDT descriptor	*/
#define	IGDT_TRAPG	15	/* Trap Gate				*/


/* Segment Descriptor */

struct sd {
	unsigned short	sd_lolimit;
	unsigned short	sd_lobase;
	unsigned char	sd_midbase;
	unsigned int	sd_perm : 3;
	unsigned int	sd_iscode : 1;
	unsigned int	sd_isapp : 1;
	unsigned int	sd_dpl : 2;
	unsigned int	sd_present : 1;
	unsigned int	sd_hilimit : 4;
	unsigned int	sd_avl : 1;
	unsigned int	sd_mbz : 1;		/* must be '0' */
	unsigned int	sd_32b : 1;
	unsigned int	sd_gran : 1;
	unsigned char	sd_hibase;
};

#define	sd_type		sd_perm

/* System Descriptor Types */

#define	SDT_INTG	14	/* Interrupt Gate	*/

/* Segment Table Register */
struct segtr {
	unsigned int	len : 16;
	unsigned int	addr : 32;
};