1 files changed, 371 insertions, 0 deletions
diff --git a/os/cerf250/devpcf8563.c b/os/cerf250/devpcf8563.c
new file mode 100644
index 00000000..f52fe60d
--- /dev/null
+++ b/os/cerf250/devpcf8563.c
@@ -0,0 +1,371 @@
+/*
+ *	Philips PCF8563 real-time clock on I⁲C (and compatibles)
+ *
+ *	currently this can't coexist with ../pxa/devrtc.c
+ */
+
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"../port/error.h"
+
+#include	"io.h"
+
+typedef struct Rtc	Rtc;
+typedef struct Rtcreg	Rtcreg;
+
+struct Rtc
+{
+	int	sec;
+	int	min;
+	int	hour;
+	int	wday;
+	int	mday;
+	int	mon;
+	int	year;
+};
+
+struct Rtcreg
+{
+	uchar	csr1;
+	uchar	csr2;
+	uchar	sec;	/* 00-59 and VL */
+	uchar	min;		/* 00-59 */
+	uchar	hour;	/* 00-23 */
+	uchar	mday;	/* 01-31 */
+	uchar	wday;	/* 0=Sun */
+	uchar	mon;	/* 1-12 and 1900 bit */
+	uchar	year;
+	uchar	amin;	/* minute alarm */
+	uchar	ahour;
+	uchar	aday;
+	uchar	awday;
+};
+
+enum{
+	Qdir = 0,
+	Qrtc,
+
+	Rtclen=	0x0C+1,		/* bytes read and written to timekeeper */
+	VL=	0x80,	/* reliable clock data no longer guaranteed */
+};
+
+static QLock	rtclock;		/* mutex on nvram operations */
+static I2Cdev	rtdev;
+
+static Dirtab rtcdir[]={
+	".",		{Qdir, 0, QTDIR},	0,	DMDIR|0555,
+	"rtc",		{Qrtc, 0},	0,	0664,
+};
+
+static ulong	rtc2sec(Rtc*);
+static void	sec2rtc(ulong, Rtc*);
+static void	setrtc(Rtc*);
+
+static void
+rtcreset(void)
+{
+	rtdev.addr = 0x51;
+	rtdev.salen = 1;
+	i2csetup(1);
+}
+
+static Chan*
+rtcattach(char *spec)
+{
+	return devattach('r', spec);
+}
+
+static Walkqid*
+rtcwalk(Chan *c, Chan *nc, char **name, int nname)
+{
+	return devwalk(c, nc, name, nname, rtcdir, nelem(rtcdir), devgen);
+}
+
+static int	 
+rtcstat(Chan *c, uchar *dp, int n)
+{
+	return devstat(c, dp, n, rtcdir, nelem(rtcdir), devgen);
+}
+
+static Chan*
+rtcopen(Chan *c, int omode)
+{
+	omode = openmode(omode);
+	switch((ulong)c->qid.path){
+	case Qrtc:
+		if(strcmp(up->env->user, eve)!=0 && omode!=OREAD)
+			error(Eperm);
+		break;
+	}
+	return devopen(c, omode, rtcdir, nelem(rtcdir), devgen);
+}
+
+static void	 
+rtcclose(Chan*)
+{
+}
+
+static long	 
+rtcread(Chan *c, void *buf, long n, vlong offset)
+{
+	ulong t, ot;
+
+	if(c->qid.type & QTDIR)
+		return devdirread(c, buf, n, rtcdir, nelem(rtcdir), devgen);
+
+	switch((ulong)c->qid.path){
+	case Qrtc:
+		qlock(&rtclock);
+		t = rtctime();
+		do{
+			ot = t;
+			t = rtctime();	/* make sure there's no skew */
+		}while(t != ot);
+		qunlock(&rtclock);
+		return readnum(offset, buf, n, t, 12);
+	}
+	error(Egreg);
+	return -1;		/* never reached */
+}
+
+static long	 
+rtcwrite(Chan *c, void *buf, long n, vlong off)
+{
+	Rtc rtc;
+	ulong secs;
+	char *cp, sbuf[32];
+	ulong offset = off;
+
+	switch((ulong)c->qid.path){
+	case Qrtc:
+		if(offset!=0 || n >= sizeof(sbuf)-1)
+			error(Ebadarg);
+		memmove(sbuf, buf, n);
+		sbuf[n] = '\0';
+		/*
+		 *  read the time
+		 */
+		cp = sbuf;
+		while(*cp){
+			if(*cp>='0' && *cp<='9')
+				break;
+			cp++;
+		}
+		secs = strtoul(cp, 0, 0);
+		/*
+		 *  convert to bcd
+		 */
+		sec2rtc(secs, &rtc);
+		/*
+		 * write it
+		 */
+		setrtc(&rtc);
+		return n;
+	}
+	error(Egreg);
+	return -1;		/* never reached */
+}
+
+Dev pcf8563devtab = {
+	'r',
+	"pcf8563",
+
+	rtcreset,
+	devinit,
+	devshutdown,
+	rtcattach,
+	rtcwalk,
+	rtcstat,
+	rtcopen,
+	devcreate,
+	rtcclose,
+	rtcread,
+	devbread,
+	rtcwrite,
+	devbwrite,
+	devremove,
+	devwstat,
+};
+
+static int
+getbcd(int bcd)
+{
+	return (bcd&0x0f) + 10 * (bcd>>4);
+}
+
+static int
+putbcd(int val)
+{
+	return (val % 10) | (((val/10) % 10) << 4);
+}
+
+long	 
+rtctime(void)
+{
+	Rtc rtc;
+	Rtcreg d;
+
+	if(waserror()){
+		iprint("rtc: err %s\n", up->env->errstr);
+		return 0;
+	}
+	if(i2crecv(&rtdev, &d, Rtclen, 0) != Rtclen)
+		return 0;
+	poperror();
+	rtc.sec = getbcd(d.sec & 0x7F);
+	rtc.min = getbcd(d.min & 0x7F);
+	rtc.hour = getbcd(d.hour & 0x3F);
+	rtc.mday = getbcd(d.mday & 0x3F);
+	rtc.mon = getbcd(d.mon & 0x1f);
+	rtc.year = getbcd(d.year);
+	if(rtc.mon < 1 || rtc.mon > 12)
+		return 0;
+	if(d.mon & (1<<7))
+		rtc.year += 1900;
+	else
+		rtc.year += 2000;
+	return rtc2sec(&rtc);
+}
+
+static void
+setrtc(Rtc *rtc)
+{
+	Rtcreg d;
+
+	memset(&d, 0, sizeof(d));
+	d.year = putbcd(rtc->year % 100);
+	d.mon = putbcd(rtc->mon);
+	if(rtc->year <  2000)
+		d.mon |= 1<<7;
+	d.wday = rtc->wday+1;
+	d.mday = putbcd(rtc->mday);
+	d.hour = putbcd(rtc->hour);
+	d.min = putbcd(rtc->min);
+	d.sec = putbcd(rtc->sec);
+	i2csend(&rtdev, &d, Rtclen, 0);
+}
+
+#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
+ */
+static int *
+yrsize(int y)
+{
+
+	if((y%4) == 0 && ((y%100) != 0 || (y%400) == 0))
+		return ldmsize;
+	else
+		return dmsize;
+}
+
+/*
+ *  compute seconds since Jan 1 1970
+ */
+static ulong
+rtc2sec(Rtc *rtc)
+{
+	ulong secs;
+	int i;
+	int *d2m;
+
+	secs = 0;
+
+	/*
+	 *  seconds per year
+	 */
+	for(i = 1970; i < rtc->year; i++){
+		d2m = yrsize(i);
+		secs += d2m[0] * SEC2DAY;
+	}
+
+	/*
+	 *  seconds per month
+	 */
+	d2m = yrsize(rtc->year);
+	for(i = 1; i < rtc->mon; i++)
+		secs += d2m[i] * SEC2DAY;
+
+	secs += (rtc->mday-1) * SEC2DAY;
+	secs += rtc->hour * SEC2HOUR;
+	secs += rtc->min * SEC2MIN;
+	secs += rtc->sec;
+
+	return secs;
+}
+
+/*
+ *  compute rtc from seconds since Jan 1 1970
+ */
+static void
+sec2rtc(ulong secs, Rtc *rtc)
+{
+	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;
+	}
+
+	/*
+	 * day is the day number.
+	 * generate day of the week.
+	 * The addend is 4 mod 7 (1/1/1970 was Thursday)
+	 */
+
+	rtc->wday = (day + 7340036L) % 7;
+
+	/*
+	 * generate hours:minutes:seconds
+	 */
+	rtc->sec = hms % 60;
+	d = hms / 60;
+	rtc->min = d % 60;
+	d /= 60;
+	rtc->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);
+	rtc->year = d;
+
+	/*
+	 * generate month
+	 */
+	d2m = yrsize(rtc->year);
+	for(d = 1; day >= d2m[d]; d++)
+		day -= d2m[d];
+	rtc->mday = day + 1;
+	rtc->mon = d;
+}