diff options
Diffstat (limited to 'drivers/rtc/bfin_rtc.c')
| -rw-r--r-- | drivers/rtc/bfin_rtc.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/drivers/rtc/bfin_rtc.c b/drivers/rtc/bfin_rtc.c new file mode 100644 index 0000000000..5755a20bc5 --- /dev/null +++ b/drivers/rtc/bfin_rtc.c @@ -0,0 +1,117 @@ +/* + * Copyright (c) 2004-2008 Analog Devices Inc. + * + * (C) Copyright 2001 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * + * Licensed under the GPL-2 or later. + */ + +#include <common.h> +#include <command.h> +#include <rtc.h> + +#if defined(CONFIG_RTC_BFIN) && defined(CONFIG_CMD_DATE) + +#include <asm/blackfin.h> +#include <asm/mach-common/bits/rtc.h> + +#define pr_stamp() debug("%s:%s:%i: here i am\n", __FILE__, __func__, __LINE__) + +#define MIN_TO_SECS(x) (60 * (x)) +#define HRS_TO_SECS(x) (60 * MIN_TO_SECS(x)) +#define DAYS_TO_SECS(x) (24 * HRS_TO_SECS(x)) + +#define NUM_SECS_IN_MIN MIN_TO_SECS(1) +#define NUM_SECS_IN_HR HRS_TO_SECS(1) +#define NUM_SECS_IN_DAY DAYS_TO_SECS(1) + +/* Our on-chip RTC has no notion of "reset" */ +void rtc_reset(void) +{ + return; +} + +/* Wait for pending writes to complete */ +static void wait_for_complete(void) +{ + pr_stamp(); + while (!(bfin_read_RTC_ISTAT() & WRITE_COMPLETE)) + if (!(bfin_read_RTC_ISTAT() & WRITE_PENDING)) + break; + bfin_write_RTC_ISTAT(WRITE_COMPLETE); +} + +/* Enable the RTC prescaler enable register */ +int rtc_init(void) +{ + pr_stamp(); + bfin_write_RTC_PREN(0x1); + return 0; +} + +/* Set the time. Get the time_in_secs which is the number of seconds since Jan 1970 and set the RTC registers + * based on this value. + */ +void rtc_set(struct rtc_time *tmp) +{ + unsigned long remain, days, hrs, mins, secs; + + pr_stamp(); + + if (tmp == NULL) { + puts("Error setting the date/time\n"); + return; + } + + wait_for_complete(); + + /* Calculate number of seconds this incoming time represents */ + remain = mktime(tmp->tm_year, tmp->tm_mon, tmp->tm_mday, + tmp->tm_hour, tmp->tm_min, tmp->tm_sec); + + /* Figure out how many days since epoch */ + days = remain / NUM_SECS_IN_DAY; + + /* From the remaining secs, compute the hrs(0-23), mins(0-59) and secs(0-59) */ + remain = remain % NUM_SECS_IN_DAY; + hrs = remain / NUM_SECS_IN_HR; + remain = remain % NUM_SECS_IN_HR; + mins = remain / NUM_SECS_IN_MIN; + secs = remain % NUM_SECS_IN_MIN; + + /* Encode these time values into our RTC_STAT register */ + bfin_write_RTC_STAT(SET_ALARM(days, hrs, mins, secs)); +} + +/* Read the time from the RTC_STAT. time_in_seconds is seconds since Jan 1970 */ +void rtc_get(struct rtc_time *tmp) +{ + uint32_t cur_rtc_stat; + int time_in_sec; + int tm_sec, tm_min, tm_hr, tm_day; + + pr_stamp(); + + if (tmp == NULL) { + puts("Error getting the date/time\n"); + return; + } + + wait_for_complete(); + + /* Read the RTC_STAT register */ + cur_rtc_stat = bfin_read_RTC_STAT(); + + /* Convert our encoded format into actual time values */ + tm_sec = (cur_rtc_stat & RTC_SEC) >> RTC_SEC_P; + tm_min = (cur_rtc_stat & RTC_MIN) >> RTC_MIN_P; + tm_hr = (cur_rtc_stat & RTC_HR ) >> RTC_HR_P; + tm_day = (cur_rtc_stat & RTC_DAY) >> RTC_DAY_P; + + /* Calculate the total number of seconds since epoch */ + time_in_sec = (tm_sec) + MIN_TO_SECS(tm_min) + HRS_TO_SECS(tm_hr) + DAYS_TO_SECS(tm_day); + to_tm(time_in_sec, tmp); +} + +#endif |
