mirror of
https://github.com/u-boot/u-boot.git
synced 2024-12-01 00:23:29 +08:00
952061352a
Variable 'days' must be defined as signed int. Otherwise the conversion
fails for some dates, e.g. 2004-08-25. Cf function rtc_time64_to_tm() in
the Linux kernel source.
Fixes: 992c1db455 "drivers: rtc: resolve year 2038 problem in rtc_to_tm"
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
78 lines
1.8 KiB
C
78 lines
1.8 KiB
C
// 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.
|
|
*
|
|
* This function is copied from rtc_time64_to_tm() in the Linux kernel.
|
|
* But in U-Boot January is month 1 and we do not subtract 1900 from the year.
|
|
*/
|
|
void rtc_to_tm(u64 time, struct rtc_time *tm)
|
|
{
|
|
unsigned int month, year, secs;
|
|
int 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;
|
|
}
|