/* Real Time Clock Driver for Blackfin
*
* Copyright (c) 2006 by Atos Automacao Industrial Ltda.
* written by Alain Schaefer <alain.schaefer@easc.ch>
* and Antonio Giovanini <antonio@atos.com.br>
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*/
#include <rtems.h>
#include "tod.h"
#include <rtems/rtc.h>
#include <rtems/libio.h>
#include <bsp.h>
#include <libcpu/rtcRegs.h>
#include <rtems/score/todimpl.h>
/* The following are inside RTEMS -- we are violating visibility!!!
* Perhaps an API could be defined to get days since 1 Jan.
*/
extern const uint16_t _TOD_Days_to_date[2][13];
/*
* Prototypes and routines used below
*/
int Leap_years_until_now (int year);
void Init_RTC(void)
{
*((uint16_t*)RTC_PREN) = RTC_PREN_PREN; /* Enable Prescaler */
}
/*
* Read time from RTEMS' clock manager and set it to RTC
*/
void setRealTimeFromRTEMS (void)
{
rtems_time_of_day time_buffer;
rtems_status_code status;
status = rtems_clock_get( RTEMS_CLOCK_GET_TOD, &time_buffer );
if (status == RTEMS_SUCCESSFUL){
setRealTime(&time_buffer);
}
}
/*
* Read real time from RTC and set it to RTEMS' clock manager
*/
void setRealTimeToRTEMS (void)
{
rtems_time_of_day time_buffer;
getRealTime(&time_buffer);
rtems_clock_set( &time_buffer );
}
/*
* Set the RTC time
*/
int setRealTime(
const rtems_time_of_day *tod
)
{
uint32_t days;
rtems_time_of_day tod_temp;
tod_temp = *tod;
days = (tod_temp.year - TOD_BASE_YEAR) * 365 + \
_TOD_Days_to_date[0][tod_temp.month] + tod_temp.day - 1;
if (tod_temp.month < 3)
days += Leap_years_until_now (tod_temp.year - 1);
else
days += Leap_years_until_now (tod_temp.year);
*((uint32_t volatile *)RTC_STAT) = (days << RTC_STAT_DAYS_SHIFT)|
(tod_temp.hour << RTC_STAT_HOURS_SHIFT)|
(tod_temp.minute << RTC_STAT_MINUTES_SHIFT)|
tod_temp.second;
return 0;
}
/*
* Get the time from the RTC.
*/
void getRealTime(
rtems_time_of_day *tod
)
{
uint32_t days, rtc_reg;
rtems_time_of_day tod_temp = { 0, 0, 0 };
int n, Leap_year;
rtc_reg = *((uint32_t volatile *)RTC_STAT);
days = (rtc_reg >> RTC_STAT_DAYS_SHIFT) + 1;
/* finding year */
tod_temp.year = days/365 + TOD_BASE_YEAR;
if (days%365 > Leap_years_until_now (tod_temp.year - 1)) {
days = (days%365) - Leap_years_until_now (tod_temp.year - 1);
} else {
tod_temp.year--;
days = (days%365) + 365 - Leap_years_until_now (tod_temp.year - 1);
}
/* finding month and day */
Leap_year = (((!(tod_temp.year%4)) && (tod_temp.year%100)) ||
(!(tod_temp.year%400)))?1:0;
for (n=1; n<=12; n++) {
if (days <= _TOD_Days_to_date[Leap_year][n+1]) {
tod_temp.month = n;
tod_temp.day = days - _TOD_Days_to_date[Leap_year][n];
break;
}
}
tod_temp.hour = (rtc_reg & RTC_STAT_HOURS_MASK) >> RTC_STAT_HOURS_SHIFT;
tod_temp.minute = (rtc_reg & RTC_STAT_MINUTES_MASK) >> RTC_STAT_MINUTES_SHIFT;
tod_temp.second = (rtc_reg & RTC_STAT_SECONDS_MASK);
tod_temp.ticks = 0;
*tod = tod_temp;
}
/*
* Return the difference between RTC and RTEMS' clock manager time in minutes.
* If the difference is greater than 1 day, this returns 9999.
*/
int checkRealTime (void)
{
rtems_time_of_day rtems_tod;
rtems_time_of_day rtc_tod;
uint32_t rtems_time;
uint32_t rtc_time;
rtems_clock_get( RTEMS_CLOCK_GET_TOD, &rtems_tod );
getRealTime ( &rtc_tod );
rtems_time = _TOD_To_seconds( &rtems_tod );
rtc_time = _TOD_To_seconds( &rtc_tod );
return rtems_time - rtc_time;
}
int Leap_years_until_now (int year)
{
return ((year/4 - year/100 + year/400) -
((TOD_BASE_YEAR - 1)/4 - (TOD_BASE_YEAR - 1)/100 +
(TOD_BASE_YEAR - 1)/400));
}
rtems_device_driver rtc_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor_arg,
void *arg
)
{
rtems_status_code status;
/*
* Register and initialize the primary RTC's
*/
status = rtems_io_register_name( RTC_DEVICE_NAME, major, 0 );
if (status != RTEMS_SUCCESSFUL) {
rtems_fatal_error_occurred(status);
}
Init_RTC();
setRealTimeToRTEMS();
return RTEMS_SUCCESSFUL;
}
rtems_device_driver rtc_read(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
rtems_libio_rw_args_t *rw = arg;
rtems_time_of_day *tod = (rtems_time_of_day *) rw->buffer;
rw->offset = 0;
rw->bytes_moved = 0;
if (rw->count != sizeof( rtems_time_of_day)) {
return RTEMS_INVALID_SIZE;
}
getRealTime( tod);
rw->bytes_moved = rw->count;
return RTEMS_SUCCESSFUL;
}
rtems_device_driver rtc_write(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
int rv = 0;
rtems_libio_rw_args_t *rw = arg;
const rtems_time_of_day *tod = (const rtems_time_of_day *) rw->buffer;
rw->offset = 0;
rw->bytes_moved = 0;
if (rw->count != sizeof( rtems_time_of_day)) {
return RTEMS_INVALID_SIZE;
}
rv = setRealTime( tod);
if (rv != 0) {
return RTEMS_IO_ERROR;
}
rw->bytes_moved = rw->count;
return RTEMS_SUCCESSFUL;
}
rtems_device_driver rtc_open(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
return RTEMS_SUCCESSFUL;
}
rtems_device_driver rtc_close(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
return RTEMS_SUCCESSFUL;
}
rtems_device_driver rtc_control(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
return RTEMS_NOT_IMPLEMENTED;
}
