diff options
Diffstat (limited to 'usr/src/uts/sun4u/io/todblade.c')
| -rw-r--r-- | usr/src/uts/sun4u/io/todblade.c | 66 |
1 files changed, 44 insertions, 22 deletions
diff --git a/usr/src/uts/sun4u/io/todblade.c b/usr/src/uts/sun4u/io/todblade.c index aed8c769ac..3be6c1409d 100644 --- a/usr/src/uts/sun4u/io/todblade.c +++ b/usr/src/uts/sun4u/io/todblade.c @@ -19,7 +19,7 @@ * CDDL HEADER END */ /* - * Copyright 2008 Sun Microsystems, Inc. All rights reserved. + * Copyright 2010 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ @@ -93,10 +93,8 @@ _init(void) tod_ops.tod_get = todbl_get; tod_ops.tod_set = todbl_set; - tod_ops.tod_set_watchdog_timer = - todbl_set_watchdog_timer; - tod_ops.tod_clear_watchdog_timer = - todbl_clear_watchdog_timer; + tod_ops.tod_set_watchdog_timer = todbl_set_watchdog_timer; + tod_ops.tod_clear_watchdog_timer = todbl_clear_watchdog_timer; tod_ops.tod_set_power_alarm = todbl_set_power_alarm; tod_ops.tod_clear_power_alarm = todbl_clear_power_alarm; tod_ops.tod_get_cpufrequency = todbl_get_cpufrequency; @@ -155,8 +153,7 @@ todbl_get(void) } else if (!watchdog_activated && watchdog_enable) { (void) configure_wdog(WDOG_ON); } else if (watchdog_activated && - (ddi_get_lbolt() - last_pat_lbt) >= - SEC_TO_TICK(1)) { + (ddi_get_lbolt() - last_pat_lbt) >= SEC_TO_TICK(1)) { /* * PAT THE WATCHDOG!! * We dont want to accelerate the pat frequency @@ -184,15 +181,18 @@ todbl_get(void) } if (i == TODM5819_UIP_RETRY_THRESH) { /* - * We couldnt read from the tod + * We couldn't read from the TOD. */ - tod_fault_reset(); + tod_status_set(TOD_GET_FAILED); return (hrestime); } DPRINTF("todbl_get: century=%d year=%d dom=%d hrs=%d\n", rtc.rtc_century, rtc.rtc_year, rtc.rtc_dom, rtc.rtc_hrs); + /* read was successful so ensure failure flag is clear */ + tod_status_clear(TOD_GET_FAILED); + ts.tv_sec = tod_to_utc(rtc_to_tod(&rtc)); ts.tv_nsec = 0; return (ts); @@ -314,6 +314,7 @@ static void write_rtc_time(struct rtc_t *rtc) { uint8_t regb; + int i; /* * Freeze @@ -321,19 +322,40 @@ write_rtc_time(struct rtc_t *rtc) regb = RTC_GET8(RTC_B); RTC_PUT8(RTC_B, (regb | RTC_SET)); - RTC_PUT8(RTC_SEC, (rtc->rtc_sec)); - RTC_PUT8(RTC_ASEC, (rtc->rtc_asec)); - RTC_PUT8(RTC_MIN, (rtc->rtc_min)); - RTC_PUT8(RTC_AMIN, (rtc->rtc_amin)); - - RTC_PUT8(RTC_HRS, (rtc->rtc_hrs)); - RTC_PUT8(RTC_AHRS, (rtc->rtc_ahrs)); - RTC_PUT8(RTC_DOW, (rtc->rtc_dow)); - RTC_PUT8(RTC_DOM, (rtc->rtc_dom)); - - RTC_PUT8(RTC_MON, (rtc->rtc_mon)); - RTC_PUT8(RTC_YEAR, (rtc->rtc_year)); - RTC_PUT8(RTC_CENTURY, (rtc->rtc_century)); + /* + * If an update is in progress wait for the UIP flag to clear. + * If we write whilst UIP is still set there is a slight but real + * possibility of corrupting the RTC date and time registers. + * + * The expected wait is one internal cycle of the chip. We could + * simply spin but this may hang a CPU if we were to have a broken + * RTC chip where UIP is stuck, so we use a retry loop instead. + * No critical section is needed here as the UIP flag will not be + * re-asserted until we clear RTC_SET. + */ + for (i = 0; i < TODM5819_UIP_RETRY_THRESH; i++) { + if (!(RTC_GET8(RTC_A) & RTC_UIP)) { + break; + } + drv_usecwait(TODM5819_UIP_WAIT_USEC); + } + if (i < TODM5819_UIP_RETRY_THRESH) { + RTC_PUT8(RTC_SEC, (rtc->rtc_sec)); + RTC_PUT8(RTC_ASEC, (rtc->rtc_asec)); + RTC_PUT8(RTC_MIN, (rtc->rtc_min)); + RTC_PUT8(RTC_AMIN, (rtc->rtc_amin)); + + RTC_PUT8(RTC_HRS, (rtc->rtc_hrs)); + RTC_PUT8(RTC_AHRS, (rtc->rtc_ahrs)); + RTC_PUT8(RTC_DOW, (rtc->rtc_dow)); + RTC_PUT8(RTC_DOM, (rtc->rtc_dom)); + + RTC_PUT8(RTC_MON, (rtc->rtc_mon)); + RTC_PUT8(RTC_YEAR, (rtc->rtc_year)); + RTC_PUT8(RTC_CENTURY, (rtc->rtc_century)); + } else { + cmn_err(CE_WARN, "todblade: Could not write the RTC\n"); + } /* * Unfreeze |