shithub: purgatorio

ref: 3efb5bbb4061056e523858b134c555949591efe2
dir: /os/boot/puma/mem.h/

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/*
 * Memory and machine-specific definitions.  Used in C and assembler.
 */

/*
 * Sizes
 */
#define	BI2BY		8			/* bits per byte */
#define	BI2WD		32			/* bits per word */
#define	BY2WD		4			/* bytes per word */
#define	BY2PG		4096			/* bytes per page */
#define	WD2PG		(BY2PG/BY2WD)		/* words per page */
#define	PGSHIFT		12			/* log(BY2PG) */
#define	PGROUND(s)	(((s)+(BY2PG-1))&~(BY2PG-1))

#define	MAXMACH		1			/* max # cpus system can run */

/*
 * Time
 */
#define	HZ		(20)				/* clock frequency */
#define	MS2HZ		(1000/HZ)			/* millisec per clock tick */
#define	TK2SEC(t)	((t)/HZ)			/* ticks to seconds */
#define	TK2MS(t)	((((ulong)(t))*1000)/HZ)	/* ticks to milliseconds */
#define	MS2TK(t)	((((ulong)(t))*HZ)/1000)	/* milliseconds to ticks */

/*
 * Fundamental addresses
 */

/*
 *  Address spaces
 *
 *  Kernel is at 0x00008000
 */
#define	KZERO		0x00000000		/* base of kernel address space */
#define	KTZERO		KZERO			/* first address in kernel text */
#define	MACHSIZE	4096