1 /* 2 * Copyright (c) 1988 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 * 17 * @(#)clock.h 7.2 (Berkeley) 06/29/88 18 */ 19 20 #define SECDAY ((unsigned)(24*60*60)) /* seconds per day */ 21 #define SECYR ((unsigned)(365*SECDAY)) /* per common year */ 22 23 #define YRREF 1970 24 #define LEAPYEAR(year) ((year)%4==0) /* good till time becomes negative */ 25 26 /* 27 * Software clock is software interrupt level 8 28 */ 29 #define setsoftclock() mtpr(SIRR, 0x8) 30 31 /* 32 * To calculate value for interval timer register, we 33 * use the fact that 20512 yields a 60hz clock. 34 */ 35 #define hztocount(v) ((20512*60) / (v)) 36