Our implementation of rtc_to_tm() cannot handle dates of more than 0x7fffffff seconds after 1970-01-01.
Adopt the Linux kernel implementation.
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de --- v2 adopt the Linux kernel implementation --- drivers/rtc/Makefile | 1 + drivers/rtc/date.c | 43 ---------------------- drivers/rtc/i2c_rtc_emul.c | 4 ++- drivers/rtc/rtc-lib.c | 73 ++++++++++++++++++++++++++++++++++++++ include/rtc.h | 16 +++++++-- 5 files changed, 90 insertions(+), 47 deletions(-) create mode 100644 drivers/rtc/rtc-lib.c
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 09f2b08244..513e3ffc07 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_DM_RTC) += rtc-uclass.o
obj-$(CONFIG_RTC_AT91SAM9_RTT) += at91sam9_rtt.o obj-y += date.o +obj-y += rtc-lib.o obj-$(CONFIG_RTC_DAVINCI) += davinci.o obj-$(CONFIG_RTC_DS1302) += ds1302.o obj-$(CONFIG_RTC_DS1306) += ds1306.o diff --git a/drivers/rtc/date.c b/drivers/rtc/date.c index 1256ffe374..f2568cf886 100644 --- a/drivers/rtc/date.c +++ b/drivers/rtc/date.c @@ -19,10 +19,6 @@ #define days_in_year(a) (leapyear(a) ? 366 : 365) #define days_in_month(a) (month_days[(a) - 1])
-static int month_days[12] = { - 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 -}; - static int month_offset[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 }; @@ -65,45 +61,6 @@ int rtc_calc_weekday(struct rtc_time *tm) return 0; }
-int rtc_to_tm(int tim, struct rtc_time *tm) -{ - register int i; - register long hms, day; - - day = tim / SECDAY; - hms = tim % SECDAY; - - /* Hours, minutes, seconds are easy */ - tm->tm_hour = hms / 3600; - tm->tm_min = (hms % 3600) / 60; - tm->tm_sec = (hms % 3600) % 60; - - /* Number of years in days */ - for (i = STARTOFTIME; day >= days_in_year(i); i++) - day -= days_in_year(i); - tm->tm_year = i; - - /* Number of months in days left */ - if (leapyear(tm->tm_year)) - days_in_month(FEBRUARY) = 29; - for (i = 1; day >= days_in_month(i); i++) - day -= days_in_month(i); - days_in_month(FEBRUARY) = 28; - tm->tm_mon = i; - - /* Days are what is left over (+1) from all that */ - tm->tm_mday = day + 1; - - /* Zero unused fields */ - tm->tm_yday = 0; - tm->tm_isdst = 0; - - /* - * Determine the day of week - */ - return rtc_calc_weekday(tm); -} - /* * Converts Gregorian date to seconds since 1970-01-01 00:00:00. * Assumes input in normal date format, i.e. 1980-12-31 23:59:59 diff --git a/drivers/rtc/i2c_rtc_emul.c b/drivers/rtc/i2c_rtc_emul.c index bad61c377f..d4b33e59d6 100644 --- a/drivers/rtc/i2c_rtc_emul.c +++ b/drivers/rtc/i2c_rtc_emul.c @@ -96,7 +96,9 @@ static int sandbox_i2c_rtc_get(struct udevice *dev, struct rtc_time *time) now = plat->base_time; }
- return rtc_to_tm(now + plat->offset, time); + rtc_to_tm(now + plat->offset, time); + + return 0; }
static int sandbox_i2c_rtc_set(struct udevice *dev, const struct rtc_time *time) diff --git a/drivers/rtc/rtc-lib.c b/drivers/rtc/rtc-lib.c new file mode 100644 index 0000000000..b8a7a8b2d3 --- /dev/null +++ b/drivers/rtc/rtc-lib.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * rtc and date/time utility functions + * + * Copyright (C) 2005-06 Tower Technologies + * Author: Alessandro Zummo a.zummo@towertech.it + * + * U-Boot rtc_time differs from Linux rtc_time: + * - The year field takes the actual value, not year - 1900. + * - January is month 1. + */ + +#include <common.h> +#include <rtc.h> +#include <linux/math64.h> + +static const unsigned char rtc_days_in_month[] = { + 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 +}; + +#define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400) + +/* + * The number of days in the month. + */ +static int rtc_month_days(unsigned int month, unsigned int year) +{ + return rtc_days_in_month[month] + (is_leap_year(year) && month == 1); +} + +/* + * rtc_to_tm - Converts u64 to rtc_time. + * Convert seconds since 01-01-1970 00:00:00 to Gregorian date. + */ +void rtc_to_tm(u64 time, struct rtc_time *tm) +{ + unsigned int month, year, secs, days; + + days = div_u64_rem(time, 86400, &secs); + + /* day of the week, 1970-01-01 was a Thursday */ + tm->tm_wday = (days + 4) % 7; + + year = 1970 + days / 365; + days -= (year - 1970) * 365 + + LEAPS_THRU_END_OF(year - 1) + - LEAPS_THRU_END_OF(1970 - 1); + while (days < 0) { + year -= 1; + days += 365 + is_leap_year(year); + } + tm->tm_year = year; /* Not year - 1900 */ + tm->tm_yday = days + 1; + + for (month = 0; month < 11; month++) { + int newdays; + + newdays = days - rtc_month_days(month, year); + if (newdays < 0) + break; + days = newdays; + } + tm->tm_mon = month + 1; /* January = 1 */ + tm->tm_mday = days + 1; + + tm->tm_hour = secs / 3600; + secs -= tm->tm_hour * 3600; + tm->tm_min = secs / 60; + tm->tm_sec = secs - tm->tm_min * 60; + + /* Zero unused fields */ + tm->tm_isdst = 0; +} diff --git a/include/rtc.h b/include/rtc.h index 746624d799..0d964d56d5 100644 --- a/include/rtc.h +++ b/include/rtc.h @@ -208,7 +208,18 @@ void rtc_write32(int reg, u32 value); * rtc_init() - Set up the real time clock ready for use */ void rtc_init(void); -#endif +#endif /* CONFIG_DM_RTC */ + +/** + * is_leap_year - Check if year is a leap year + * + * @year Year + * @return 1 if leap year + */ +static inline bool is_leap_year(unsigned int year) +{ + return (!(year % 4) && (year % 100)) || !(year % 400); +}
/** * rtc_calc_weekday() - Work out the weekday from a time @@ -231,9 +242,8 @@ int rtc_calc_weekday(struct rtc_time *time); * * @time_t: Number of seconds since 1970-01-01 00:00:00 * @time: Place to put the broken-out time - * @return 0 if OK, -EINVAL if the weekday could not be determined */ -int rtc_to_tm(int time_t, struct rtc_time *time); +void rtc_to_tm(u64 time_t, struct rtc_time *time);
/** * rtc_mktime() - Convert a broken-out time into a time_t value