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|
/************************************************************************************
* arch/arm/src/sama5/sam_rtc.c
*
* Copyright (C) 2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
************************************************************************************/
/************************************************************************************
* Included Files
************************************************************************************/
#include <nuttx/config.h>
#include <nuttx/arch.h>
#include <nuttx/irq.h>
#include <nuttx/rtc.h>
#include <time.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/wqueue.h>
#include <arch/board/board.h>
#include "up_arch.h"
#include "sam_rtc.h"
#ifdef CONFIG_RTC
/************************************************************************************
* Pre-processor Definitions
************************************************************************************/
/* Configuration ********************************************************************/
/* This RTC implementation supports only date/time RTC hardware */
#ifndef CONFIG_RTC_DATETIME
# error "CONFIG_RTC_DATETIME must be set to use this driver"
#endif
#ifdef CONFIG_RTC_HIRES
# error "CONFIG_RTC_HIRES must NOT be set with this driver"
#endif
#if defined(CONFIG_RTC_ALARM) && !defined(CONFIG_SCHED_WORKQUEUE)
# error CONFIG_RTC_ALARM requires CONFIG_SCHED_WORKQUEUE
#endif
#define RTC_MAGIC 0xdeadbeef
#ifndef CONFIG_DEBUG
# undef CONFIG_DEBUG_RTC
#endif
/* Constants ************************************************************************/
/* Debug ****************************************************************************/
#ifdef CONFIG_DEBUG_RTC
# define rtcdbg dbg
# define rtcvdbg vdbg
# define rtclldbg lldbg
# define rtcllvdbg llvdbg
#else
# define rtcdbg(x...)
# define rtcvdbg(x...)
# define rtclldbg(x...)
# define rtcllvdbg(x...)
#endif
/************************************************************************************
* Private Types
************************************************************************************/
/************************************************************************************
* Private Data
************************************************************************************/
/* Callback to use when the alarm expires */
#ifdef CONFIG_RTC_ALARM
static alarmcb_t g_alarmcb;
struct work_s g_alarmwork;
#endif
/************************************************************************************
* Public Data
************************************************************************************/
/* g_rtc_enabled is set true after the RTC has successfully initialized */
volatile bool g_rtc_enabled = false;
/************************************************************************************
* Private Functions
************************************************************************************/
/************************************************************************************
* Name: rtc_dumpregs
*
* Description:
* Disable RTC write protection
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
************************************************************************************/
#ifdef CONFIG_DEBUG_RTC
static void rtc_dumpregs(FAR const char *msg)
{
rtclldbg("%s:\n", msg);
rtclldbg(" CR: %08x\n", getreg32(SAM_RTC_CR));
rtclldbg(" MR: %08x\n", getreg32(SAM_RTC_MR));
rtclldbg(" TIMR: %08x\n", getreg32(SAM_RTC_TIMR));
rtclldbg(" CALR: %08x\n", getreg32(SAM_RTC_CALR));
rtclldbg(" TIMALR: %08x\n", getreg32(SAM_RTC_TIMALR));
rtclldbg(" CALALR: %08x\n", getreg32(SAM_RTC_CALALR));
rtclldbg(" SR: %08x\n", getreg32(SAM_RTC_SR));
rtclldbg(" IMR: %08x\n", getreg32(SAM_RTC_IMR));
rtclldbg(" VER: %08x\n", getreg32(SAM_RTC_VER));
}
#else
# define rtc_dumpregs(msg)
#endif
/************************************************************************************
* Name: rtc_dumptime
*
* Description:
* Disable RTC write protection
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
************************************************************************************/
#ifdef CONFIG_DEBUG_RTC
static void rtc_dumptime(FAR struct tm *tp, FAR const char *msg)
{
rtclldbg("%s:\n", msg);
rtclldbg(" tm_sec: %08x\n", tp->tm_sec);
rtclldbg(" tm_min: %08x\n", tp->tm_min);
rtclldbg(" tm_hour: %08x\n", tp->tm_hour);
rtclldbg(" tm_mday: %08x\n", tp->tm_mday);
rtclldbg(" tm_mon: %08x\n", tp->tm_mon);
rtclldbg(" tm_year: %08x\n", tp->tm_year);
}
#else
# define rtc_dumptime(tp, msg)
#endif
/************************************************************************************
* Name: rtc_bin2bcd
*
* Description:
* Converts a 2 digit binary to BCD format
*
* Input Parameters:
* value - The byte to be converted.
*
* Returned Value:
* The value in BCD representation
*
************************************************************************************/
static uint32_t rtc_bin2bcd(int value)
{
uint32_t msbcd = 0;
while (value >= 10)
{
msbcd++;
value -= 10;
}
return (msbcd << 4) | value;
}
/************************************************************************************
* Name: rtc_bin2bcd
*
* Description:
* Convert from 2 digit BCD to binary.
*
* Input Parameters:
* value - The BCD value to be converted.
*
* Returned Value:
* The value in binary representation
*
************************************************************************************/
static int rtc_bcd2bin(uint32_t value)
{
uint32_t tens = (value >> 4) * 10;
return (int)(tens + (value & 0x0f));
}
/************************************************************************************
* Name: rtc_worker
*
* Description:
* Perform alarm callback
*
* Input Parameters:
* Standard work callbacks
*
* Returned Value:
* Zero (OK) on success; A negated errno value on failure.
*
************************************************************************************/
#if CONFIG_RTC_ALARM
static void rtc_worker(FAR void *arg)
{
/* Sample once (atomically) */
alarmcb_t alarmcb = g_alarmcb;
/* Is there a subscriber to the alarm? */
if (alarmcb)
{
/* Yes.. perform the callback */
alarmcb();
}
}
#endif
/************************************************************************************
* Name: rtc_interrupt
*
* Description:
* RTC interrupt service routine
*
* Input Parameters:
* irq - The IRQ number that generated the interrupt
* context - Architecture specific register save information.
*
* Returned Value:
* Zero (OK) on success; A negated errno value on failure.
*
************************************************************************************/
#if CONFIG_RTC_ALARM
static int rtc_interrupt(int irq, void *context)
{
int ret;
/* Schedule the callback to occur on the low-priority worker thread */
DEBUGASSERT(work_available(&g_alarmwork));
ret = work_queue(LPWORK, &g_alarmwork, rtc_worker, NULL, 0);
if (ret < 0)
{
rtclldbg("ERRPR: work_queue failed: %d\n", ret);
}
/* Disable any further alarm interrupts*/
putreg32(RTC_IDR_ALRDIS, SAM_RTC_IDR);
/* Clear any pending alarm interrupts */
putreg32(RTC_SCCR_ALRCLR, SAM_RTC_SCCR);
return OK;
}
#endif
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: up_rtcinitialize
*
* Description:
* Initialize the hardware RTC per the selected configuration. This function is
* called once during the OS initialization sequence
*
* Input Parameters:
* None
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
int up_rtcinitialize(void)
{
uint32_t ver;
rtc_dumpregs("On reset");
/* No clocking setup need be performed. The Real-time Clock is continuously clocked
* at 32768 Hz (SCLK). The Power Management Controller has no effect on RTC
* behavior.
*/
/* Set the 24 hour format */
putreg32(0, SAM_RTC_MR);
/* Has the RTC been initialized? */
ver = getreg32(SAM_RTC_VER);
g_rtc_enabled = ((ver & (RTC_VER_NVTIM | RTC_VER_NVCAL)) == 0);
#ifdef CONFIG_RTC_ALARM
/* Then attach the ALARM interrupt handler */
irq_attach(SAM_PID_SYS, rtc_interrupt);
/* Should RTC alarm interrupt be enabled at the peripheral? Let's assume so
* for now. Let's say yes if the time is valid and a valid alarm has been
* programmed.
*/
if (g_rtc_enabled && (ver & (RTC_VER_NVTIMALR | RTC_VER_NVCALALR)) == 0)
{
/* Enable the alarm interrupt at the RTC */
putreg32(RTC_IER_ALREN, SAM_RTC_IER);
}
else
{
/* Disable the alarm interrupt at the RTC */
putreg32(RTC_IDR_ALRDIS, SAM_RTC_IDR);
}
/* Enable SYSC interrupts at the AIC in any event */
up_enable_irq(SAM_PID_SYS);
#endif
rtc_dumpregs("After Initialization");
return OK;
}
/************************************************************************************
* Name: up_rtc_getdatetime
*
* Description:
* Get the current date and time from the date/time RTC. This interface
* is only supported by the date/time RTC hardware implementation.
* It is used to replace the system timer. It is only used by the RTOS during
* intialization to set up the system time when CONFIG_RTC and CONFIG_RTC_DATETIME
* are selected (and CONFIG_RTC_HIRES is not).
*
* NOTE: Some date/time RTC hardware is capability of sub-second accuracy. That
* sub-second accuracy is lost in this interface. However, since the system time
* is reinitialized on each power-up/reset, there will be no timing inaccuracy in
* the long run.
*
* Input Parameters:
* tp - The location to return the high resolution time value.
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
int up_rtc_getdatetime(FAR struct tm *tp)
{
uint32_t timr;
uint32_t calr;
uint32_t cent;
uint32_t year;
uint32_t tmp;
/* Sample the data time registers. There is a race condition here... If we sample
* the time just before midnight on December 31, the date could be wrong because
* the day rolled over while were sampling.
*/
do
{
calr = getreg32(SAM_RTC_CALR);
timr = getreg32(SAM_RTC_TIMR);
tmp = getreg32(SAM_RTC_CALR);
}
while (tmp != calr);
rtc_dumpregs("Reading Time");
/* Convert the RTC time register fields to struct tm format.
*
* struct tm TIMR register
* tm_sec 0-61* SEC (0-59)
* tm_min 0-59 MIN (0-59)
* tm_hour 0-23 HOUR (0-23)
*
* *To allow for leap seconds. But these never actuall happen.
*/
tmp = (timr & RTC_TIMR_SEC_MASK) >> RTC_TIMR_SEC_SHIFT;
tp->tm_sec = rtc_bcd2bin(tmp);
tmp = (timr & RTC_TIMR_MIN_MASK) >> RTC_TIMR_MIN_SHIFT;
tp->tm_min = rtc_bcd2bin(tmp);
tmp = (timr & RTC_TIMR_HOUR_MASK) >> RTC_TIMR_HOUR_SHIFT;
tp->tm_hour = rtc_bcd2bin(tmp);
/* Convert the RTC date register fields to struct tm format.
*
* struct tm TIMR register
* tm_mday 1-31 DATE (1-31)
* tm_wday 0-6 DAY (1-7) **
* tm_mon 0-11 MONTH: (1-12)
* tm_year * YEAR (0-99)
* CENT (19-20)
*
* *Years since 1900
* **Day of the week is not supported
*/
tmp = (calr & RTC_CALR_DATE_MASK) >> RTC_CALR_DATE_SHIFT;
tp->tm_mday = rtc_bcd2bin(tmp);
tmp = (calr & RTC_CALR_MONTH_MASK) >> RTC_CALR_MONTH_SHIFT;
tp->tm_mon = rtc_bcd2bin(tmp) - 1;
tmp = (calr & RTC_CALR_CENT_MASK) >> RTC_CALR_CENT_SHIFT;
cent = rtc_bcd2bin(tmp);
tmp = (calr & RTC_CALR_YEAR_MASK) >> RTC_CALR_YEAR_SHIFT;
year = rtc_bcd2bin(tmp);
tp->tm_year = cent * 100 + year - 1900;
rtc_dumptime(tp, "Returning");
return OK;
}
/************************************************************************************
* Name: up_rtc_settime
*
* Description:
* Set the RTC to the provided time. All RTC implementations must be able to
* set their time based on a standard timespec.
*
* Input Parameters:
* tp - the time to use
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
int up_rtc_settime(FAR const struct timespec *tp)
{
FAR struct tm newtime;
uint32_t regval;
uint32_t timr;
uint32_t calr;
uint32_t cent;
uint32_t year;
/* Break out the time values (note that the time is set only to units of seconds) */
(void)gmtime_r(&tp->tv_sec, &newtime);
rtc_dumptime(&newtime, "Setting time");
/* Then write the broken out values to the RTC */
/* Convert the struct tm format to RTC time register fields.
*
* struct tm TIMR register
* tm_sec 0-61* SEC (0-59)
* tm_min 0-59 MIN (0-59)
* tm_hour 0-23 HOUR (0-23)
*
* *To allow for leap seconds. But these never actuall happen.
*/
timr = (rtc_bin2bcd(newtime.tm_sec) << RTC_TIMR_SEC_SHIFT) & RTC_TIMR_SEC_MASK;
timr |= (rtc_bin2bcd(newtime.tm_min) << RTC_TIMR_MIN_SHIFT) & RTC_TIMR_MIN_MASK;
timr |= (rtc_bin2bcd(newtime.tm_hour) << RTC_TIMR_HOUR_SHIFT) & RTC_TIMR_HOUR_MASK;
/* Convert the struct tm format to RTC date register fields.
*
* struct tm CALR register
* tm_mday 1-31 DATE (1-31)
* tm_wday 0-6 DAY (1-7) **
* tm_mon 0-11 MONTH: (1-12)
* tm_year * YEAR (0-99)
* CENT (19-20)
*
* *Years since 1900
* **Day of the week is not supported. Set to Monday.
*/
calr = (rtc_bin2bcd(newtime.tm_mday) << RTC_CALR_DATE_SHIFT) & RTC_CALR_DATE_MASK;
calr |= (rtc_bin2bcd(1) << RTC_CALR_DAY_SHIFT) & RTC_CALR_DAY_MASK;
calr |= (rtc_bin2bcd(newtime.tm_mon+1) << RTC_CALR_MONTH_SHIFT) & RTC_CALR_MONTH_MASK;
cent = newtime.tm_year / 100 + 19;
year = newtime.tm_year % 100;
calr |= (rtc_bin2bcd(year) << RTC_CALR_YEAR_SHIFT) & RTC_CALR_YEAR_MASK;
calr |= (rtc_bin2bcd(cent) << RTC_CALR_CENT_SHIFT) & RTC_CALR_CENT_MASK;
/* Stop RTC time and date counting */
regval = getreg32(SAM_RTC_CR);
regval |= (RTC_CR_UPDTIM | RTC_CR_UPDCAL);
putreg32(regval, SAM_RTC_CR);
/* Wait until the RTC has stopped so that we can update the time */
while ((getreg32(SAM_RTC_SR) & RTC_SR_ACKUPD) != RTC_SR_ACKUPD);
/* Clear the ACKUPD bit in the status register */
putreg32(RTC_SCCR_ACKCLR, SAM_RTC_SCCR);
/* Set the new date */
putreg32(calr, SAM_RTC_CALR);
/* Write the new time */
putreg32(timr, SAM_RTC_TIMR);
/* Resume RTC date/time counting */
regval = getreg32(SAM_RTC_CR);
regval &= ~(RTC_CR_UPDTIM | RTC_CR_UPDCAL);
putreg32(regval, SAM_RTC_CR);
/* Clear the SEC status in the SR */
regval = getreg32(SAM_RTC_SCCR);
regval = RTC_SCCR_SECCLR;
putreg32(regval, SAM_RTC_SCCR);
/* The RTC should now be enabled */
g_rtc_enabled = ((getreg32(SAM_RTC_VER) & (RTC_VER_NVTIM | RTC_VER_NVCAL)) == 0);
DEBUGASSERT(g_rtc_enabled);
rtc_dumpregs("New time setting");
return OK;
}
/************************************************************************************
* Name: up_rtc_setalarm
*
* Description:
* Set up an alarm. Up to two alarms can be supported (ALARM A and ALARM B).
*
* Input Parameters:
* tp - the time to set the alarm
* callback - the function to call when the alarm expires.
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
#ifdef CONFIG_RTC_ALARM
int up_rtc_setalarm(FAR const struct timespec *tp, alarmcb_t callback)
{
FAR struct tm newalarm;
irqstate_t flags;
uint32_t timalr;
uint32_t calalr;
int ret = -EBUSY;
/* Is there already something waiting on the ALARM? */
flags = irqsave();
if (g_alarmcb == NULL)
{
/* No.. Save the callback function pointer */
g_alarmcb = callback;
/* Clear any pending alarm interrupts */
putreg32(RTC_SCCR_ALRCLR, SAM_RTC_SCCR);
/* Break out the time values (note that the time is set only to units
* of seconds)
*/
(void)gmtime_r(&tp->tv_sec, &newalarm);
rtc_dumptime(&newalarm, "Setting alarm");
/* Then write the broken out values to the RTC */
/* Convert the struct tm format to RTC time register fields.
*
* struct tm TIMALR register
* tm_sec 0-61* SEC (0-59)
* tm_min 0-59 MIN (0-59)
* tm_hour 0-23 HOUR (0-23)
*
* *To allow for leap seconds. But these never actuall happen.
*/
timalr = (rtc_bin2bcd(newalarm.tm_sec) << RTC_TIMALR_SEC_SHIFT) & RTC_TIMALR_SEC_MASK;
timalr |= (rtc_bin2bcd(newalarm.tm_min) << RTC_TIMALR_MIN_SHIFT) & RTC_TIMALR_MIN_MASK;
timalr |= (rtc_bin2bcd(newalarm.tm_hour) << RTC_TIMALR_HOUR_SHIFT) & RTC_TIMALR_HOUR_MASK;
timalr |= (RTC_TIMALR_SECEN | RTC_TIMALR_MINEN | RTC_TIMALR_HOUREN);
/* Convert the struct tm format to RTC date register fields.
*
* struct tm CALALR register
* tm_mday 1-31 DATE (1-31)
* tm_wday 0-6 DAY (1-7) **
* tm_mon 0-11 MONTH: (1-12)
* tm_year * YEAR (0-99)
* CENT (19-20)
*
* *Years since 1900
* **Day of the week is not supported
*/
calalr = (rtc_bin2bcd(newalarm.tm_mday) << RTC_CALALR_DATE_SHIFT) & RTC_CALALR_DATE_MASK;
calalr |= (rtc_bin2bcd(newalarm.tm_mon+1) << RTC_CALALR_MONTH_SHIFT) & RTC_CALALR_MONTH_MASK;
calalr |= (RTC_CALALR_MTHEN | RTC_CALALR_DATEEN);
/* Set the new date */
putreg32(calalr, SAM_RTC_CALALR);
/* Write the new time */
putreg32(timalr, SAM_RTC_TIMALR);
DEBUGASSERT((getreg32(SAM_RTC_VER) & RTC_VER_NVTIMALR) == 0);
DEBUGASSERT((getreg32(SAM_RTC_VER) & RTC_VER_NVCALALR) == 0);
rtc_dumpregs("New alarm setting");
/* Enable alarm interrupts */
putreg32(RTC_IER_ALREN, SAM_RTC_IER);
ret = OK;
}
irqrestore(flags);
return ret;
}
#endif
#endif /* CONFIG_RTC */
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