This fixes a bug in read_persistent_clock() which causes the system clock to lag the Real Time Clock by one month. The problem was noticed on a Mac, but theoretically it must also affect Atari, BVME6000 and Q40.
The tm_mon value in the struct rtc_time passed to mach_hwclk() is zero-based, and atari_mste_hwclk(), atari_tt_hwclk(), bvme6000_hwclk(), mac_hwclk() and q40_hwclk() all make this adjustment. Unfortunately, dn_dummy_hwclk(), mvme147_hwclk(), mvme16x_hwclk(), sun3_hwclk() and sun3x_hwclk() fail to decrement tm_mon. Bring these platforms into line and fix read_persistent_clock() so it works correctly on all m68k platforms. The datasheets for the RTC devices found on the affected platforms all confirm that the year is stored as a value in the range 0-99 and the month is stored as a value in the range 1-12. Please refer to the datasheets for MC146818 (Apollo), DS1643 (MVME), ICM7170 (Sun 3) and M48T02 (Sun 3x). Reported-by: Stan Johnson <[email protected]> Signed-off-by: Finn Thain <[email protected]> --- arch/m68k/apollo/config.c | 8 +++++--- arch/m68k/kernel/time.c | 14 +++++++------- arch/m68k/mvme147/config.c | 4 +++- arch/m68k/mvme16x/config.c | 4 +++- arch/m68k/sun3/intersil.c | 8 +++++--- arch/m68k/sun3x/time.c | 8 +++++--- 6 files changed, 28 insertions(+), 18 deletions(-) diff --git a/arch/m68k/apollo/config.c b/arch/m68k/apollo/config.c index 0d27706f14d4..8a5f98904af3 100644 --- a/arch/m68k/apollo/config.c +++ b/arch/m68k/apollo/config.c @@ -221,8 +221,10 @@ int dn_dummy_hwclk(int op, struct rtc_time *t) { t->tm_hour=rtc->hours; t->tm_mday=rtc->day_of_month; t->tm_wday=rtc->day_of_week; - t->tm_mon=rtc->month; + t->tm_mon = rtc->month - 1; t->tm_year=rtc->year; + if (t->tm_year < 70) + t->tm_year += 100; } else { rtc->second=t->tm_sec; rtc->minute=t->tm_min; @@ -230,8 +232,8 @@ int dn_dummy_hwclk(int op, struct rtc_time *t) { rtc->day_of_month=t->tm_mday; if(t->tm_wday!=-1) rtc->day_of_week=t->tm_wday; - rtc->month=t->tm_mon; - rtc->year=t->tm_year; + rtc->month = t->tm_mon + 1; + rtc->year = t->tm_year % 100; } return 0; diff --git a/arch/m68k/kernel/time.c b/arch/m68k/kernel/time.c index 97dd4e26f234..6b4389a6e8ea 100644 --- a/arch/m68k/kernel/time.c +++ b/arch/m68k/kernel/time.c @@ -74,17 +74,17 @@ static irqreturn_t timer_interrupt(int irq, void *dummy) void read_persistent_clock(struct timespec *ts) { struct rtc_time time; + ts->tv_sec = 0; ts->tv_nsec = 0; - if (mach_hwclk) { - mach_hwclk(0, &time); + if (!mach_hwclk) + return; + + mach_hwclk(0, &time); - if ((time.tm_year += 1900) < 1970) - time.tm_year += 100; - ts->tv_sec = mktime(time.tm_year, time.tm_mon, time.tm_mday, - time.tm_hour, time.tm_min, time.tm_sec); - } + ts->tv_sec = mktime(time.tm_year + 1900, time.tm_mon + 1, time.tm_mday, + time.tm_hour, time.tm_min, time.tm_sec); } #if defined(CONFIG_ARCH_USES_GETTIMEOFFSET) && IS_ENABLED(CONFIG_RTC_DRV_GENERIC) diff --git a/arch/m68k/mvme147/config.c b/arch/m68k/mvme147/config.c index 8778612d1f31..f8a710fd84cd 100644 --- a/arch/m68k/mvme147/config.c +++ b/arch/m68k/mvme147/config.c @@ -153,12 +153,14 @@ int mvme147_hwclk(int op, struct rtc_time *t) if (!op) { m147_rtc->ctrl = RTC_READ; t->tm_year = bcd2int (m147_rtc->bcd_year); - t->tm_mon = bcd2int (m147_rtc->bcd_mth); + t->tm_mon = bcd2int(m147_rtc->bcd_mth) - 1; t->tm_mday = bcd2int (m147_rtc->bcd_dom); t->tm_hour = bcd2int (m147_rtc->bcd_hr); t->tm_min = bcd2int (m147_rtc->bcd_min); t->tm_sec = bcd2int (m147_rtc->bcd_sec); m147_rtc->ctrl = 0; + if (t->tm_year < 70) + t->tm_year += 100; } return 0; } diff --git a/arch/m68k/mvme16x/config.c b/arch/m68k/mvme16x/config.c index 6fa06d4d16bf..4ffd9ef98de4 100644 --- a/arch/m68k/mvme16x/config.c +++ b/arch/m68k/mvme16x/config.c @@ -400,12 +400,14 @@ int mvme16x_hwclk(int op, struct rtc_time *t) if (!op) { rtc->ctrl = RTC_READ; t->tm_year = bcd2int (rtc->bcd_year); - t->tm_mon = bcd2int (rtc->bcd_mth); + t->tm_mon = bcd2int(rtc->bcd_mth) - 1; t->tm_mday = bcd2int (rtc->bcd_dom); t->tm_hour = bcd2int (rtc->bcd_hr); t->tm_min = bcd2int (rtc->bcd_min); t->tm_sec = bcd2int (rtc->bcd_sec); rtc->ctrl = 0; + if (t->tm_year < 70) + t->tm_year += 100; } return 0; } diff --git a/arch/m68k/sun3/intersil.c b/arch/m68k/sun3/intersil.c index 2cd0bcbe6f30..d911070af02a 100644 --- a/arch/m68k/sun3/intersil.c +++ b/arch/m68k/sun3/intersil.c @@ -48,9 +48,9 @@ int sun3_hwclk(int set, struct rtc_time *t) todintersil->hour = t->tm_hour; todintersil->minute = t->tm_min; todintersil->second = t->tm_sec; - todintersil->month = t->tm_mon; + todintersil->month = t->tm_mon + 1; todintersil->day = t->tm_mday; - todintersil->year = t->tm_year - 68; + todintersil->year = (t->tm_year - 68) % 100; todintersil->weekday = t->tm_wday; } else { /* read clock */ @@ -58,10 +58,12 @@ int sun3_hwclk(int set, struct rtc_time *t) t->tm_hour = todintersil->hour; t->tm_min = todintersil->minute; t->tm_sec = todintersil->second; - t->tm_mon = todintersil->month; + t->tm_mon = todintersil->month - 1; t->tm_mday = todintersil->day; t->tm_year = todintersil->year + 68; t->tm_wday = todintersil->weekday; + if (t->tm_year < 70) + t->tm_year += 100; } intersil_clock->cmd_reg = START_VAL; diff --git a/arch/m68k/sun3x/time.c b/arch/m68k/sun3x/time.c index 7a2c53d9f779..047e2bcee3d7 100644 --- a/arch/m68k/sun3x/time.c +++ b/arch/m68k/sun3x/time.c @@ -52,8 +52,8 @@ int sun3x_hwclk(int set, struct rtc_time *t) h->hour = bin2bcd(t->tm_hour); h->wday = bin2bcd(t->tm_wday); h->mday = bin2bcd(t->tm_mday); - h->month = bin2bcd(t->tm_mon); - h->year = bin2bcd(t->tm_year); + h->month = bin2bcd(t->tm_mon + 1); + h->year = bin2bcd(t->tm_year % 100); h->csr &= ~C_WRITE; } else { h->csr |= C_READ; @@ -62,9 +62,11 @@ int sun3x_hwclk(int set, struct rtc_time *t) t->tm_hour = bcd2bin(h->hour); t->tm_wday = bcd2bin(h->wday); t->tm_mday = bcd2bin(h->mday); - t->tm_mon = bcd2bin(h->month); + t->tm_mon = bcd2bin(h->month) - 1; t->tm_year = bcd2bin(h->year); h->csr &= ~C_READ; + if (t->tm_year < 70) + t->tm_year += 100; } local_irq_restore(flags); -- 2.16.1
