1990/1204/power/devrtc.c (diff list | history)

power/devrtc.c on 1990/1204
1990/1204		#include "u.h" #include "lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "errno.h" #include "devtab.h" #include "io.h" typedef struct Rtc Rtc; struct Rtc { QLock; int sec; int min; int hour; int mday; int mon; int year; }; Rtc rtc; Dirtab rtcdir[]={ "rtc", {1}, 0, 0600, }; static uchar pattern[] = { 0xc5, 0x3a, 0xa3, 0x5c, 0xc5, 0x3a, 0xa3, 0x5c }; /* * issue pattern recognition bits to nv ram to address the * real time clock */ rtcpattern(void) { uchar *nv; uchar ch; int i, j; nv = RTC; /* * read the pattern sequence pointer to reset it */ ch = *nv; /* * stuff the pattern recognition codes one bit at * a time into *nv. */ for(i = 0; i < sizeof(pattern); i++){ ch = pattern[i]; for (j = 0; j < 8; j++){ *nv = ch & 0x1; ch >>= 1; } } } void rtcreset(void) { } void rtcinit(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) { if(c->qid.path != CHDIR) return 0; if(strcmp(name, "rtc") == 0){ c->qid.path = 1; return 1; } return 0; } void rtcstat(Chan *c, char *dp) { devstat(c, dp, rtcdir, 1, devgen); } Chan* rtcopen(Chan *c, int omode) { c->mode = openmode(omode); c->flag |= COPEN; c->offset = 0; return c; } void rtccreate(Chan *c, char *name, int omode, ulong perm) { error(Eperm); } void rtcclose(Chan *c) { } #define GETBCD(o) ((clock[o]&0xf) + 10*(clock[o]>>4)) long rtcread(Chan *c, void *buf, long n) { int i,j; uchar ch; uchar *nv; uchar clock[8]; char atime[64]; if(c->offset!=0) error(Ebadarg); nv = RTC; /* * set up the pattern for the clock */ qlock(&rtc); rtcpattern(); /* * read out the clock one bit at a time */ for (i = 0; i < 8; i++){ ch = 0; for (j = 0; j < 8; j++) ch |= ((*nv & 0x1) << j); clock[i] = ch; } qunlock(&rtc); rtc.sec = GETBCD(1); rtc.min = GETBCD(2); rtc.hour = GETBCD(3); rtc.mday = GETBCD(5); rtc.mon = GETBCD(6); rtc.year = GETBCD(7); /* * the world starts jan 1 1970 */ if(rtc.year < 70) rtc.year += 2000; else rtc.year += 1900; sprint(atime, "%.2d:%.2d:%.2d %d/%d/%d", rtc.hour, rtc.min, rtc.sec, rtc.mon, rtc.mday, rtc.year); i = strlen(atime); if(c->offset >= i) return 0; if(c->offset + n > i) n = i - c->offset; strncpy(buf, &atime[c->offset], n); return n; } static int perm[] = { 3, 2, 1, 6, 5, 7 }; long rtcwrite(Chan *c, void *buf, long n) { int i,j; uchar ch; uchar clock[8]; uchar *nv; char *cp; if(c->offset!=0) error(Ebadarg); /* * parse (most any separator will do) */ ch = 0; j = 0; clock[0] = clock[4] = 0; cp = buf; for(i = 0; i < n; i++){ switch(*cp){ case ':': case ' ': case '\t': case '/': case '-': clock[perm[j++]] = ch; ch = 0; break; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': ch = (ch<<4) | (*cp - '0'); break; default: error(Ebadarg); } cp++; } clock[perm[j++]] = ch; if(j != 6) error(Ebadarg); /* * set up the pattern for the clock */ qlock(&rtc); rtcpattern(); /* * write the clock one bit at a time */ nv = RTC; for (i = 0; i < 8; i++){ ch = clock[i]; for (j = 0; j < 8; j++){ *nv = ch & 1; ch >>= 1; } } qunlock(&rtc); return n; } void rtcremove(Chan *c) { error(Eperm); } void rtcwstat(Chan *c, char *dp) { error(Eperm); } #define SEC2MIN 60 #define SEC2HOUR (60*SEC2MIN) #define SEC2DAY (24*SEC2HOUR) #define SEC2YR (365*SEC2DAY) static char dmsize[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; /* * compute seconds since Jan 1 1970 */ ulong rtc2sec(void) { ulong secs; int i; for(i = 1970; i < rtc.year; i++) secs += dysize(i); for(i = 0; i < rtc.mon-1; i++) secs += dmsize[i] * SEC2DAY; if(dysize(rtc.year)==366 && rtc.mon>2) secs += 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 */ sec2rtc(ulong secs) { int d0, d1; long hms, day; /* * break initial number into days */ hms = secs % SEC2DAY; day = secs / SEC2DAY; if(hms < 0) { hms += SEC2DAY; day -= 1; } /* * generate hours:minutes:seconds */ rtc.sec = hms % SEC2MIN; d1 = hms / SEC2MIN; rtc.min = d1 % SEC2MIN; d1 /= SEC2MIN; rtc.hour = d1; /* * year number */ if(day >= 0) for(d1 = 70; day >= dysize(d1); d1++) day -= dysize(d1); else for (d1 = 70; day < 0; d1--) day += dysize(d1-1); rtc.year = d1; /* * generate month */ if(dysize(d1) == 366) dmsize[1] = 29; for(d1 = 0; d0 >= dmsize[d1]; d1++) d0 -= dmsize[d1]; dmsize[1] = 28; rtc.mday = d0 + 1; rtc.mon = d1; return; } /* * days to year */ static dysize(int y) { if((y%4) == 0) return 366; return 365; }