#include	"u.h"#include	"../port/lib.h"#include	"mem.h"#include	"dat.h"#include	"fns.h"#include	"../port/error.h"#include	"devtab.h" #include	"io.h" typedef struct Rtc	Rtc;typedef struct Time	Time; struct Rtc{	QLock;	int	new;		/* is a new chip */}; struct Time{	int	sec;	int	min;	int	hour;	int	mday;	int	mon;	int	year;}; Rtc	rtc;enum{	Qrtc = 1,	Qnvram,}; #define	NRTC	1Dirtab rtcdir[]={	"rtc",		{Qrtc, 0},	0,	0666,}; ulong rtc2sec(Time*);void sec2rtc(ulong, Time*);int *yrsize(int); voidrtcreset(void){	qlock(&rtc);	qunlock(&rtc);	if(getcc(0x30) & 0x80)		rtc.new = 1;} voidrtcinit(void){} Chan*rtcattach(char *spec){	return devattach('r', spec);} Chan*rtcclone(Chan *c, Chan *nc){	return devclone(c, nc);} int	 rtcwalk(Chan *c, char *name){	return devwalk(c, name, rtcdir, NRTC, devgen);} void	 rtcstat(Chan *c, char *dp){	devstat(c, dp, rtcdir, NRTC, devgen);} Chan*rtcopen(Chan *c, int omode){	omode = openmode(omode);	switch(c->qid.path){	case Qrtc:		if(strcmp(u->p->user, eve)!=0 && omode!=OREAD)			error(Eperm);		break;	case Qnvram:		if(strcmp(u->p->user, eve)!=0 || !cpuserver)			error(Eperm);	}	return devopen(c, omode, rtcdir, NRTC, devgen);} void	 rtccreate(Chan *c, char *name, int omode, ulong perm){	USED(c, name, omode, perm);	error(Eperm);} void	 rtcclose(Chan *c){	USED(c);} #define GETBCD(v) (((v)&0xf) + 10*((v)>>4))#define TOBCD(v) ((v) % 10) | ((((v) / 10) % 10)<<4) longrtctime(void){	ulong t;	Time r; 	if(rtc.new){		t  = getcc(0x20)<<24;		t |= getcc(0x21)<<16;		t |= getcc(0x22)<< 8;		t |= getcc(0x23)<< 0;	}else{			/*		 *  convert from BCD		 */		r.sec = GETBCD(getcc(0x20)&0x7F);		r.min = GETBCD(getcc(0x21)&0x7F);		t = getcc(0x22);		if(t & (1<<7)){	/* 12-hour mode */			r.hour = GETBCD(t&0x1F);			if(t & (1<<5))				r.hour += 12;		}else			r.hour = GETBCD(t&0x7F);		r.mday = GETBCD(getcc(0x24)&0x3F);		r.mon = GETBCD(getcc(0x25)&0x1F);		r.year = GETBCD(getcc(0x26));			/*		 *  the world starts jan 1 1970		 */		if(r.year < 70)			r.year += 2000;		else			r.year += 1900;		t = rtc2sec(&r);	}	return t;} long	 rtcread(Chan *c, void *buf, long n, ulong offset){	ulong t, ot; 	if(c->qid.path & CHDIR)		return devdirread(c, buf, n, rtcdir, NRTC, devgen); 	qlock(&rtc);	t = rtctime();	do{		ot = t;		t = rtctime();	/* make sure there's no skew */	}while(t != ot);	qunlock(&rtc);	n = readnum(offset, buf, n, t, 12);	return n; } long	 rtcwrite(Chan *c, void *buf, long n, ulong offset){	Time r;	ulong t;	int i, cc;	char *cp, *ep; 	USED(c); 	if(offset!=0)		error(Ebadarg); 	/*	 *  read the time	 */	cp = ep = buf;	ep += n;	while(cp < ep){		if(*cp>='0' && *cp<='9')			break;		cp++;	}	t = strtoul(cp, 0, 0); 	qlock(&rtc);	cc = getcc(0x31);	cc &= ~(1<<7);	putcc(0x31, cc);		/* stop clock */	if(rtc.new)		for(i=4; --i>=0; )			putcc(0x20+i, (t>>(24-8*i))&0xFF);	else{		sec2rtc(t, &r);		putcc(0x20, TOBCD(r.sec));		putcc(0x21, TOBCD(r.min));		putcc(0x22, (1<<7)|TOBCD(r.hour));	/* put in 24hr mode */		putcc(0x23, 0);		putcc(0x24, TOBCD(r.mday));		putcc(0x25, TOBCD(r.mon));		putcc(0x26, TOBCD(r.year%100));	}	putcc(0x31, cc|(1<<7));		/* start clock */	qunlock(&rtc); 	return n;} void	 rtcremove(Chan *c){	USED(c);	error(Eperm);} void	 rtcwstat(Chan *c, char *dp){	USED(c, dp);	error(Eperm);} #define SEC2MIN 60L#define SEC2HOUR (60L*SEC2MIN)#define SEC2DAY (24L*SEC2HOUR) /* *  days per month plus days/year */static	int	dmsize[] ={	365, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};static	int	ldmsize[] ={	366, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; /* *  return the days/month for the given year */int *yrsize(int yr){	if((yr % 4) == 0)		return ldmsize;	else		return dmsize;} /* *  compute seconds since Jan 1 1970 */ulongrtc2sec(Time *t){	ulong secs;	int i;	int *d2m; 	secs = 0; 	/*	 *  seconds per year	 */	for(i = 1970; i < t->year; i++){		d2m = yrsize(i);		secs += d2m[0] * SEC2DAY;	} 	/*	 *  seconds per month	 */	d2m = yrsize(t->year);	for(i = 1; i < t->mon; i++)		secs += d2m[i] * SEC2DAY; 	secs += (t->mday-1) * SEC2DAY;	secs += t->hour * SEC2HOUR;	secs += t->min * SEC2MIN;	secs += t->sec; 	return secs;} /* *  compute rtc from seconds since Jan 1 1970 */voidsec2rtc(ulong secs, Time *t){	int d;	long hms, day;	int *d2m; 	/*	 * break initial number into days	 */	hms = secs % SEC2DAY;	day = secs / SEC2DAY;	if(hms < 0) {		hms += SEC2DAY;		day -= 1;	} 	/*	 * generate hours:minutes:seconds	 */	t->sec = hms % 60;	d = hms / 60;	t->min = d % 60;	d /= 60;	t->hour = d; 	/*	 * year number	 */	if(day >= 0)		for(d = 1970; day >= *yrsize(d); d++)			day -= *yrsize(d);	else		for (d = 1970; day < 0; d--)			day += *yrsize(d-1);	t->year = d; 	/*	 * generate month	 */	d2m = yrsize(t->year);	for(d = 1; day >= d2m[d]; d++)		day -= d2m[d];	t->mday = day + 1;	t->mon = d;}