leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

m68k: Fix off-by-one calendar month

Browse Source 
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.  Also m68328_hwclk() assumes
a one-based 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 <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
This commit is contained in:
Finn Thain 2018-04-23 11:02:57 +10:00 committed by Geert Uytterhoeven
parent 4eee57d68b
commit b65769fc01
7 changed files with 31 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
arch/m68k/68000/timers.c
View File

@ -125,7 +125,9 @@ int m68328_hwclk(int set, struct rtc_time *t)
{
if (!set) {
long now = RTCTIME;
t->tm_year = t->tm_mon = t->tm_mday = 1;
t->tm_year = 1;
t->tm_mon = 0;
t->tm_mday = 1;
t->tm_hour = (now >> 24) % 24;
t->tm_min = (now >> 16) % 60;
t->tm_sec = now % 60;

8
arch/m68k/apollo/config.c
View File

@ -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;

14
arch/m68k/kernel/time.c
View File

@ -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;
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);
}
mach_hwclk(0, &time);
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)

4
arch/m68k/mvme147/config.c
View File

@ -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;
}

4
arch/m68k/mvme16x/config.c
View File

@ -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;
}

8
arch/m68k/sun3/intersil.c
View File

@ -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;

8
arch/m68k/sun3x/time.c
View File

@ -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);