/*
- * arch/ppc/platforms/chrp_time.c
- *
* Copyright (C) 1991, 1992, 1995 Linus Torvalds
*
* Adapted for PowerPC (PReP) by Gary Thomas
void chrp_get_rtc_time(struct rtc_time *tm)
{
unsigned int year, mon, day, hour, min, sec;
- int uip, i;
-
- /* The Linux interpretation of the CMOS clock register contents:
- * When the Update-In-Progress (UIP) flag goes from 1 to 0, the
- * RTC registers show the second which has precisely just started.
- * Let's hope other operating systems interpret the RTC the same way.
- */
- /* Since the UIP flag is set for about 2.2 ms and the clock
- * is typically written with a precision of 1 jiffy, trying
- * to obtain a precision better than a few milliseconds is
- * an illusion. Only consistency is interesting, this also
- * allows to use the routine for /dev/rtc without a potential
- * 1 second kernel busy loop triggered by any reader of /dev/rtc.
- */
-
- for ( i = 0; i<1000000; i++) {
- uip = chrp_cmos_clock_read(RTC_FREQ_SELECT);
+ do {
sec = chrp_cmos_clock_read(RTC_SECONDS);
min = chrp_cmos_clock_read(RTC_MINUTES);
hour = chrp_cmos_clock_read(RTC_HOURS);
day = chrp_cmos_clock_read(RTC_DAY_OF_MONTH);
mon = chrp_cmos_clock_read(RTC_MONTH);
year = chrp_cmos_clock_read(RTC_YEAR);
- uip |= chrp_cmos_clock_read(RTC_FREQ_SELECT);
- if ((uip & RTC_UIP)==0) break;
- }
+ } while (sec != chrp_cmos_clock_read(RTC_SECONDS));
if (!(chrp_cmos_clock_read(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
BCD_TO_BIN(sec);
tm->tm_mon = mon;
tm->tm_year = year;
}
-
-
-void __init chrp_calibrate_decr(void)
-{
- struct device_node *cpu;
- unsigned int freq, *fp;
-
- /*
- * The cpu node should have a timebase-frequency property
- * to tell us the rate at which the decrementer counts.
- */
- freq = 16666000; /* hardcoded default */
- cpu = find_type_devices("cpu");
- if (cpu != 0) {
- fp = (unsigned int *)
- get_property(cpu, "timebase-frequency", NULL);
- if (fp != 0)
- freq = *fp;
- }
- ppc_tb_freq = freq;
-}