Add SAM3/4 RTT driver. From Bob Doiron

This commit is contained in:
Gregory Nutt 2014-05-05 14:35:37 -06:00
parent dcc709e612
commit 2cbb9b907c
5 changed files with 923 additions and 30 deletions

View File

@ -134,6 +134,10 @@ ifeq ($(CONFIG_SAM34_RTC),y)
CHIP_CSRCS += sam_rtc.c CHIP_CSRCS += sam_rtc.c
endif endif
ifeq ($(CONFIG_SAM34_RTT),y)
CHIP_CSRCS += sam_rtt.c
endif
ifeq ($(CONFIG_SAM34_WDT),y) ifeq ($(CONFIG_SAM34_WDT),y)
CHIP_CSRCS += sam_wdt.c CHIP_CSRCS += sam_wdt.c
endif endif

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@ -54,20 +54,25 @@
#include "up_arch.h" #include "up_arch.h"
#include "sam_rtc.h" #include "sam_rtc.h"
#if defined(CONFIG_RTC_HIRES) && defined (CONFIG_SAM34_RTT)
# include "sam_rtt.h"
# include "sam_periphclks.h"
#endif
#ifdef CONFIG_RTC #ifdef CONFIG_RTC
/************************************************************************************ /************************************************************************************
* Pre-processor Definitions * Pre-processor Definitions
************************************************************************************/ ************************************************************************************/
/* Configuration ********************************************************************/ /* 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 #ifdef CONFIG_RTC_HIRES
# error "CONFIG_RTC_HIRES must NOT be set with this driver" # if !defined(CONFIG_SAM34_RTT)
# error RTT is required to emulate high resolution RTC
# endif
# if (CONFIG_RTC_FREQUENCY > 32768) || ((32768 % CONFIG_RTC_FREQUENCY) != 0)
# error CONFIG_RTC_FREQUENCY must be an integer division of 32768
# endif
#endif #endif
#if defined(CONFIG_RTC_ALARM) && !defined(CONFIG_SCHED_WORKQUEUE) #if defined(CONFIG_RTC_ALARM) && !defined(CONFIG_SCHED_WORKQUEUE)
@ -119,6 +124,12 @@ struct work_s g_alarmwork;
volatile bool g_rtc_enabled = false; volatile bool g_rtc_enabled = false;
/* g_rtt_offset holds the rtt->rtc count offset */
#if defined(CONFIG_RTC_HIRES) && defined (CONFIG_SAM34_RTT)
uint32_t g_rtt_offset = 0;
#endif
/************************************************************************************ /************************************************************************************
* Private Functions * Private Functions
************************************************************************************/ ************************************************************************************/
@ -302,6 +313,40 @@ static int rtc_interrupt(int irq, void *context)
} }
#endif #endif
/************************************************************************************
* Name: rtc_sync
*
* Description:
* Waits and returns immediately after 1 sec tick. For best accuracy,
* call with interrupts disabled.
*
* Returns value of the TIMR register
*
************************************************************************************/
static uint32_t rtc_sync(void)
{
uint32_t r0, r1;
/* Get start second (stable) */
do
{
r0 = getreg32(SAM_RTC_TIMR);
}
while (r0 != getreg32(SAM_RTC_TIMR));
/* Now read until it changes */
do
{
r1 = getreg32(SAM_RTC_TIMR);
}
while (r1 == r0);
return r1;
}
/************************************************************************************ /************************************************************************************
* Public Functions * Public Functions
************************************************************************************/ ************************************************************************************/
@ -370,6 +415,32 @@ int up_rtcinitialize(void)
#endif #endif
#if defined(CONFIG_RTC_HIRES) && defined (CONFIG_SAM34_RTT)
/* Using the RTT for subsecond ticks. */
sam_rtt_enableclk();
/* Disable ints, set prescaler, start counter */
putreg32(RTT_MR_RTPRES(32768/CONFIG_RTC_FREQUENCY) | RTT_MR_RTTRST, SAM_RTT_MR);
/* wait for a second tick to get the RTT offset.
* Interrupts are assumed to still be off at this point.
*/
rtc_sync();
/* Probably safe to read the RTT_VR register now since the clock just ticked,
* but we'll be careful anyway.
*/
do
{
g_rtt_offset = getreg32(SAM_RTT_VR);
}
while(getreg32(SAM_RTT_VR) != g_rtt_offset);
#endif
rtc_dumpregs("After Initialization"); rtc_dumpregs("After Initialization");
return OK; return OK;
} }
@ -681,4 +752,55 @@ int up_rtc_setalarm(FAR const struct timespec *tp, alarmcb_t callback)
} }
#endif #endif
/************************************************************************************
* Name: up_rtc_gettime
*
* Description:
* Get the current time from the high resolution RTC clock/counter. This interface
* is only supported by the high-resolution RTC/counter hardware implementation.
* It is used to replace the system timer.
*
* Input Parameters:
* tp - The location to return the high resolution time value.
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
#if defined(CONFIG_RTC_HIRES) && defined (CONFIG_SAM34_RTT)
int up_rtc_gettime(FAR struct timespec *tp)
{
/* This is a hack to emulate a high resolution rtc using the rtt */
uint32_t rtc_cal, rtc_tim, rtt_val;
struct tm t;
do
{
rtc_cal = getreg32(SAM_RTC_CALR);
rtc_tim = getreg32(SAM_RTC_TIMR);
rtt_val = getreg32(SAM_RTT_VR);
} while((rtc_cal != getreg32(SAM_RTC_CALR)) ||
(rtc_tim != getreg32(SAM_RTC_TIMR)) ||
(rtt_val != getreg32(SAM_RTT_VR)));
t.tm_sec = rtc_bcd2bin((rtc_tim & RTC_TIMR_SEC_MASK) >> RTC_TIMR_SEC_SHIFT);
t.tm_min = rtc_bcd2bin((rtc_tim & RTC_TIMR_MIN_MASK) >> RTC_TIMR_MIN_SHIFT);
t.tm_hour = rtc_bcd2bin((rtc_tim & RTC_TIMR_HOUR_MASK) >> RTC_TIMR_HOUR_SHIFT);
t.tm_mday = rtc_bcd2bin((rtc_cal & RTC_CALR_DATE_MASK) >> RTC_CALR_DATE_SHIFT);
t.tm_mon = rtc_bcd2bin((rtc_cal & RTC_CALR_MONTH_MASK) >> RTC_CALR_MONTH_SHIFT);
t.tm_year = (rtc_bcd2bin((rtc_cal & RTC_CALR_CENT_MASK) >> RTC_CALR_CENT_SHIFT) * 100)
+ rtc_bcd2bin((rtc_cal & RTC_CALR_YEAR_MASK) >> RTC_CALR_YEAR_SHIFT)
- 1900;
tp->tv_sec = mktime(&t);
tp->tv_nsec = (((rtt_val-g_rtt_offset) & (CONFIG_RTC_FREQUENCY-1)) * 1000000000ULL) /
CONFIG_RTC_FREQUENCY;
return OK;
}
#endif
#endif /* CONFIG_RTC */ #endif /* CONFIG_RTC */

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@ -0,0 +1,668 @@
/****************************************************************************
* arch/arm/src/sam34/sam_rtt.c
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Authors: Gregory Nutt <gnutt@nuttx.org>
* Bob Dioron
*
* 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 <sys/types.h>
#include <stdint.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/timer.h>
#include <arch/board/board.h>
#include "up_arch.h"
#include "sam_rtt.h"
#include "sam_periphclks.h"
#if defined(CONFIG_TIMER) && (defined(CONFIG_SAM34_RTT))
/****************************************************************************
* Pre-Processor Definitions
****************************************************************************/
/* Clocking *****************************************************************/
#if defined(CONFIG_RTC_HIRES) && defined (CONFIG_SAM34_RTC)
# define RTT_PRES (32768/CONFIG_RTC_FREQUENCY)
#else
/* TODO: Allow prescaler selection. */
# define RTT_PRES 1
#endif
#define RTT_FCLK (BOARD_SLCK_FREQUENCY/RTT_PRES)
#define RTT_MAXTIMEOUT ((1000000ULL * (0x100000000ULL)) / RTT_FCLK)
/* Configuration ************************************************************/
/* Debug ********************************************************************/
/* Non-standard debug that may be enabled just for testing the timer
* driver. NOTE: that only lldbg types are used so that the output is
* immediately available.
*/
#ifdef CONFIG_DEBUG_RTT
# define rttdbg lldbg
# define rttvdbg llvdbg
#else
# define rttdbg(x...)
# define rttvdbg(x...)
#endif
/****************************************************************************
* Private Types
****************************************************************************/
/* This structure provides the private representation of the "lower-half"
* driver state structure. This structure must be cast-compatible with the
* timer_lowerhalf_s structure.
*/
struct sam34_lowerhalf_s
{
FAR const struct timer_ops_s *ops; /* Lower half operations */
/* Private data */
tccb_t handler; /* Current user interrupt handler */
uint32_t timeout; /* The current timeout value (us) */
uint32_t clkticks; /* actual clock ticks for current interval */
uint32_t val; /* rtt value of current timeout */
uint32_t adjustment; /* time lost due to clock resolution truncation (us) */
bool started; /* The timer has been started */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* Register operations ******************************************************/
#if defined(CONFIG_SAM34_RTT_REGDEBUG) && defined(CONFIG_DEBUG)
static uint32_t sam34_getreg(uint32_t addr);
static void sam34_putreg(uint32_t val, uint32_t addr);
#else
# define sam34_getreg(addr) getreg32(addr)
# define sam34_putreg(val,addr) putreg32(val,addr)
#endif
/* Interrupt handling *******************************************************/
static int sam34_interrupt(int irq, FAR void *context);
/* "Lower half" driver methods **********************************************/
static int sam34_start(FAR struct timer_lowerhalf_s *lower);
static int sam34_stop(FAR struct timer_lowerhalf_s *lower);
static int sam34_getstatus(FAR struct timer_lowerhalf_s *lower,
FAR struct timer_status_s *status);
static int sam34_settimeout(FAR struct timer_lowerhalf_s *lower,
uint32_t timeout);
static tccb_t sam34_sethandler(FAR struct timer_lowerhalf_s *lower,
tccb_t handler);
static int sam34_ioctl(FAR struct timer_lowerhalf_s *lower, int cmd,
unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
/* "Lower half" driver methods */
static const struct timer_ops_s g_tcops =
{
.start = sam34_start,
.stop = sam34_stop,
.getstatus = sam34_getstatus,
.settimeout = sam34_settimeout,
.sethandler = sam34_sethandler,
.ioctl = sam34_ioctl,
};
/* "Lower half" driver state */
static struct sam34_lowerhalf_s g_tcdev;
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: sam34_readvr
*
* Description:
* Get the contents of the value register.
*
****************************************************************************/
static inline uint32_t sam34_readvr(void)
{
register uint32_t v;
/* Async counter, read until two consecutive reads match */
do
{
v = getreg32(SAM_RTT_VR);
}
while(v != getreg32(SAM_RTT_VR));
return v;
}
/****************************************************************************
* Name: sam34_getreg
*
* Description:
* Get the contents of a register
*
****************************************************************************/
#if defined(CONFIG_SAM34_RTT_REGDEBUG) && defined(CONFIG_DEBUG)
static uint32_t sam34_getreg(uint32_t addr)
{
static uint32_t prevaddr = 0;
static uint32_t count = 0;
static uint32_t preval = 0;
/* Read the value from the register */
uint32_t val = getreg32(addr);
/* Is this the same value that we read from the same registe last time? Are
* we polling the register? If so, suppress some of the output.
*/
if (addr == prevaddr && val == preval)
{
if (count == 0xffffffff || ++count > 3)
{
if (count == 4)
{
lldbg("...\n");
}
return val;
}
}
/* No this is a new address or value */
else
{
/* Did we print "..." for the previous value? */
if (count > 3)
{
/* Yes.. then show how many times the value repeated */
lldbg("[repeats %d more times]\n", count-3);
}
/* Save the new address, value, and count */
prevaddr = addr;
preval = val;
count = 1;
}
/* Show the register value read */
lldbg("%08lx->%08lx\n", addr, val);
return val;
}
#endif
/****************************************************************************
* Name: sam34_putreg
*
* Description:
* Set the contents of an SAM34 register to a value
*
****************************************************************************/
#if defined(CONFIG_SAM34_RTT_REGDEBUG) && defined(CONFIG_DEBUG)
static void sam34_putreg(uint32_t val, uint32_t addr)
{
/* Show the register value being written */
lldbg("%08lx<-%08lx\n", addr, val);
/* Write the value */
putreg32(val, addr);
}
#endif
/****************************************************************************
* Name: sam34_interrupt
*
* Description:
* TC interrupt
*
* Input Parameters:
* Usual interrupt handler arguments.
*
* Returned Values:
* Always returns OK.
*
****************************************************************************/
static int sam34_interrupt(int irq, FAR void *context)
{
FAR struct sam34_lowerhalf_s *priv = &g_tcdev;
rttvdbg("Entry\n");
DEBUGASSERT(irq == SAM_IRQ_RTT);
/* Check if the interrupt is really pending */
if ((sam34_getreg(SAM_RTT_SR) & RTT_SR_ALMS) != 0)
{
uint32_t timeout;
uint32_t mrval;
uint32_t vr;
uint32_t lateticks;
/* Is there a registered handler? */
if (priv->handler && priv->handler(&priv->timeout))
{
/* Disable int before writing new alarm */
mrval = sam34_getreg(SAM_RTT_MR);
sam34_putreg(mrval & ~RTT_MR_ALMIEN, SAM_RTT_MR);
/* Calculate new ticks / dither adjustment */
vr = sam34_readvr();
priv->clkticks =
((uint64_t)(priv->adjustment + priv->timeout)) * RTT_FCLK / 1000000;
/* Subtract off how late we are, but only up to half an interval.
* TODO calculate lost ticks?
*/
lateticks = vr - priv->val;
if (lateticks <= (priv->clkticks>>1))
{
priv->clkticks -= lateticks;
}
/* Set next interval interval. */
priv->val = vr + priv->clkticks;
sam34_putreg(priv->val-1, SAM_RTT_AR);
/* Re-enable alarm */
sam34_putreg(mrval, SAM_RTT_MR);
/* Truncated timeout */
timeout = (1000000ULL * priv->clkticks) / RTT_FCLK;
/* Truncated time to be added to next interval (dither) */
priv->adjustment = (priv->adjustment + priv->timeout) - timeout;
}
else /* stop */
{
sam34_stop((FAR struct timer_lowerhalf_s *)priv);
}
/* RTT_SR_ALMS is cleared by reading SAM_RTT_SR */
}
return OK;
}
/****************************************************************************
* Name: sam34_start
*
* Description:
* Start the timer, resetting the time to the current timeout,
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower-half"
* driver state structure.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int sam34_start(FAR struct timer_lowerhalf_s *lower)
{
FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower;
uint32_t mr;
uint32_t vr;
rttvdbg("Entry\n");
DEBUGASSERT(priv);
if (priv->started)
{
return -EINVAL;
}
#if defined(CONFIG_RTC_HIRES) && defined (CONFIG_SAM34_RTC)
/* RTT is started with the RTC and always on */
mr = sam34_getreg(SAM_RTT_MR) & ~RTT_MR_ALMIEN;
sam34_putreg(mr, SAM_RTT_MR);
vr = sam34_readvr();
#else
sam_rtt_enableclk(); /* Enable peripheral clock */
mr = RTT_MR_RTPRES(RTT_PRES);
sam34_putreg(mr, SAM_RTT_MR); /* Set prescaler, disable ints */
vr = 0; /* we're going to reset the counter */
#endif
priv->val = vr + priv->clkticks; /* value at end of interval */
sam34_putreg(priv->val-1, SAM_RTT_AR); /* Set interval */
if (priv->handler)
{
/* Clear status and enable interrupt */
sam34_getreg(SAM_RTT_SR);
mr |= RTT_MR_ALMIEN;
sam34_putreg(mr, SAM_RTT_MR);
}
#if !(defined(CONFIG_RTC_HIRES) && defined (CONFIG_SAM34_RTC))
sam34_putreg(mr | RTT_MR_RTTRST, SAM_RTT_MR); /* Start counter */
#endif /* !(CONFIG_RTC_HIRES && CONFIG_SAM34_RTC) */
priv->started = true;
return OK;
}
/****************************************************************************
* Name: sam34_stop
*
* Description:
* Stop the timer
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower-half"
* driver state structure.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int sam34_stop(FAR struct timer_lowerhalf_s *lower)
{
FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower;
rttvdbg("Entry\n");
DEBUGASSERT(priv);
if(!priv->started)
{
return -EINVAL;
}
#if !(defined(CONFIG_RTC_HIRES) && defined (CONFIG_SAM34_RTC))
sam34_putreg(RTT_MR_RTTDIS, SAM_RTT_MR); /* Disable RTT */
sam_rtt_disableclk(); /* Disable peripheral clock */
#endif
priv->started = false;
return OK;
}
/****************************************************************************
* Name: sam34_getstatus
*
* Description:
* Get the current timer status
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower-half"
* driver state structure.
* status - The location to return the status information.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int sam34_getstatus(FAR struct timer_lowerhalf_s *lower,
FAR struct timer_status_s *status)
{
FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower;
rttvdbg("Entry\n");
DEBUGASSERT(priv);
/* Return the status bit */
status->flags = 0;
if (priv->started)
{
status->flags |= TCFLAGS_ACTIVE;
}
if (priv->handler)
{
status->flags |= TCFLAGS_HANDLER;
}
/* Return the actual timeout is milliseconds */
status->timeout = priv->timeout;
/* Get the time remaining until the timer expires (in microseconds) */
status->timeleft = 1000000ULL*(sam34_getreg(SAM_RTT_AR) - sam34_readvr())/RTT_FCLK;
rttvdbg(" flags : %08x\n", status->flags);
rttvdbg(" timeout : %d\n", status->timeout);
rttvdbg(" timeleft : %d\n", status->timeleft);
return OK;
}
/****************************************************************************
* Name: sam34_settimeout
*
* Description:
* Set a new timeout value (and reset the timer)
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower-half"
* driver state structure.
* timeout - The new timeout value in milliseconds.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int sam34_settimeout(FAR struct timer_lowerhalf_s *lower,
uint32_t timeout)
{
FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower;
DEBUGASSERT(priv);
rttvdbg("Entry: timeout=%d\n", timeout);
if(priv->started) return -EPERM;
/* Can this timeout be represented? */
if (timeout < 1 || timeout > RTT_MAXTIMEOUT)
{
rttdbg("Cannot represent timeout=%lu > %lu\n",
timeout, RTT_MAXTIMEOUT);
return -ERANGE;
}
priv->timeout = timeout; /* Intended timeout */
priv->clkticks = (((uint64_t)timeout * RTT_FCLK) / 1000000); /* Actual clock ticks */
timeout = (1000000ULL * priv->clkticks) / RTT_FCLK; /* Truncated timeout */
priv->adjustment = priv->timeout - timeout; /* Truncated time to be added to next interval (dither) */
rttvdbg("fclk=%d clkticks=%d timout=%d, adjustment=%d\n",
RTT_FCLK, priv->clkticks, priv->timeout, priv->adjustment);
return OK;
}
/****************************************************************************
* Name: sam34_sethandler
*
* Description:
* Call this user provided timeout handler.
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower-half"
* driver state structure.
* newhandler - The new timer expiration function pointer. If this
* function pointer is NULL, then the reset-on-expiration
* behavior is restored,
*
* Returned Values:
* The previous timer expiration function pointer or NULL is there was
* no previous function pointer.
*
****************************************************************************/
static tccb_t sam34_sethandler(FAR struct timer_lowerhalf_s *lower,
tccb_t handler)
{
FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower;
irqstate_t flags;
tccb_t oldhandler;
flags = irqsave();
DEBUGASSERT(priv);
rttvdbg("Entry: handler=%p\n", handler);
/* Get the old handler return value */
oldhandler = priv->handler;
/* Save the new handler */
priv->handler = handler;
irqrestore(flags);
return oldhandler;
}
/****************************************************************************
* Name: sam34_ioctl
*
* Description:
* Any ioctl commands that are not recognized by the "upper-half" driver
* are forwarded to the lower half driver through this method.
*
* Input Parameters:
* lower - A pointer the publicly visible representation of the "lower-half"
* driver state structure.
* cmd - The ioctl command value
* arg - The optional argument that accompanies the 'cmd'. The
* interpretation of this argument depends on the particular
* command.
*
* Returned Values:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
static int sam34_ioctl(FAR struct timer_lowerhalf_s *lower, int cmd,
unsigned long arg)
{
FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower;
int ret = -ENOTTY;
DEBUGASSERT(priv);
rttvdbg("Entry: cmd=%d arg=%ld\n", cmd, arg);
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: sam_rttinitialize
*
* Description:
* Initialize the timer. The timer is initialized and registers as
* 'devpath'.
*
* Input Parameters:
* devpath - The full path to the timer. This should be of the form
* /dev/rtt0
*
* Returned Values:
* None
*
****************************************************************************/
void sam_rttinitialize(FAR const char *devpath)
{
FAR struct sam34_lowerhalf_s *priv = &g_tcdev;
rttvdbg("Entry: devpath=%s\n", devpath);
/* Initialize the driver state structure. Here we assume: (1) the state
* structure lies in .bss and was zeroed at reset time. (2) This function
* is only called once so it is never necessary to re-zero the structure.
*/
priv->ops = &g_tcops;
(void)irq_attach(SAM_IRQ_RTT, sam34_interrupt);
/* Enable NVIC interrupt. */
up_enable_irq(SAM_IRQ_RTT);
/* Register the timer driver as /dev/timerX */
(void)timer_register(devpath, (FAR struct timer_lowerhalf_s *)priv);
}
#endif /* CONFIG_TIMER && CONFIG_SAM34_TCx */

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@ -0,0 +1,100 @@
/****************************************************************************
* arch/arm/src/sam34/sam_rtt.h
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Authors: Gregory Nutt <gnutt@nuttx.org>
* Bob Doiron
*
* 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.
*
****************************************************************************/
#ifndef __ARCH_ARM_SRC_SAM34_RTT_H
#define __ARCH_ARM_SRC_SAM34_RTT_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include "chip.h"
#include "chip/sam_rtt.h"
#ifdef CONFIG_TIMER
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef __ASSEMBLY__
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
#if defined(CONFIG_SAM34_RTT)
/****************************************************************************
* Name: sam_rttinitialize
*
* Description:
* Initialize the timer. The timer is initialized and registers as
* 'devpath. The initial state of the timer is disabled.
*
* Input Parameters:
* devpath - The full path to the timer. This should be of the form
* /dev/rtt0
*
* Returned Values:
* None
*
****************************************************************************/
void sam_rttinitialize(FAR const char *devpath);
#endif // CONFIG_SAM34_RTT
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __ASSEMBLY__ */
#endif /* CONFIG_TIMER */
#endif /* __ARCH_ARM_SRC_SAM34_RTT_H */

View File

@ -106,7 +106,6 @@ struct sam34_lowerhalf_s
uint32_t clkticks; /* actual clock ticks for current interval */ uint32_t clkticks; /* actual clock ticks for current interval */
bool started; /* The timer has been started */ bool started; /* The timer has been started */
uint16_t periphid; /* peripheral id */ uint16_t periphid; /* peripheral id */
uint16_t debug;
}; };
/**************************************************************************** /****************************************************************************
@ -134,7 +133,7 @@ static int sam34_getstatus(FAR struct timer_lowerhalf_s *lower,
FAR struct timer_status_s *status); FAR struct timer_status_s *status);
static int sam34_settimeout(FAR struct timer_lowerhalf_s *lower, static int sam34_settimeout(FAR struct timer_lowerhalf_s *lower,
uint32_t timeout); uint32_t timeout);
static tccb_t sam34_capture(FAR struct timer_lowerhalf_s *lower, static tccb_t sam34_sethandler(FAR struct timer_lowerhalf_s *lower,
tccb_t handler); tccb_t handler);
static int sam34_ioctl(FAR struct timer_lowerhalf_s *lower, int cmd, static int sam34_ioctl(FAR struct timer_lowerhalf_s *lower, int cmd,
unsigned long arg); unsigned long arg);
@ -150,7 +149,7 @@ static const struct timer_ops_s g_tcops =
.stop = sam34_stop, .stop = sam34_stop,
.getstatus = sam34_getstatus, .getstatus = sam34_getstatus,
.settimeout = sam34_settimeout, .settimeout = sam34_settimeout,
.capture = sam34_capture, .sethandler = sam34_sethandler,
.ioctl = sam34_ioctl, .ioctl = sam34_ioctl,
}; };
@ -267,15 +266,13 @@ static void sam34_putreg(uint32_t val, uint32_t addr)
static int sam34_interrupt(int irq, FAR void *context) static int sam34_interrupt(int irq, FAR void *context)
{ {
FAR struct sam34_lowerhalf_s *priv = &g_tcdevs[irq-SAM_IRQ_TC0]; FAR struct sam34_lowerhalf_s *priv = &g_tcdevs[irq-SAM_IRQ_TC0];
uint16_t regval;
tcvdbg("Entry\n"); tcvdbg("Entry\n");
DEBUGASSERT((irq >= SAM_IRQ_TC0) && (irq <= SAM_IRQ_TC5)); DEBUGASSERT((irq >= SAM_IRQ_TC0) && (irq <= SAM_IRQ_TC5));
/* Check if the interrupt is really pending */ /* Check if the interrupt is really pending */
regval = sam34_getreg(priv->base + SAM_TC_SR_OFFSET); if ((sam34_getreg(priv->base + SAM_TC_SR_OFFSET) & TC_INT_CPCS) != 0)
if ((regval & TC_INT_CPCS) != 0)
{ {
uint32_t timeout; uint32_t timeout;
@ -283,7 +280,7 @@ static int sam34_interrupt(int irq, FAR void *context)
if (priv->handler && priv->handler(&priv->timeout)) if (priv->handler && priv->handler(&priv->timeout))
{ {
/* Calculate new ticks */ /* Calculate new ticks / dither adjustment */
priv->clkticks = ((uint64_t)(priv->adjustment + priv->timeout))*TC_FCLK / 1000000; priv->clkticks = ((uint64_t)(priv->adjustment + priv->timeout))*TC_FCLK / 1000000;
@ -323,7 +320,7 @@ static int sam34_interrupt(int irq, FAR void *context)
static int sam34_start(FAR struct timer_lowerhalf_s *lower) static int sam34_start(FAR struct timer_lowerhalf_s *lower)
{ {
FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower; FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower;
uint32_t mr_val = 0; uint32_t mr_val;
tcvdbg("Entry\n"); tcvdbg("Entry\n");
DEBUGASSERT(priv); DEBUGASSERT(priv);
@ -335,13 +332,14 @@ static int sam34_start(FAR struct timer_lowerhalf_s *lower)
sam_enableperiph0(priv->periphid); /* Enable peripheral clock */ sam_enableperiph0(priv->periphid); /* Enable peripheral clock */
sam34_putreg(TC_CCR_CLKDIS, priv->base + SAM_TC_CCR_OFFSET); /* Disable counter */ sam34_putreg(TC_CCR_CLKDIS, priv->base + SAM_TC_CCR_OFFSET); /* Disable counter */
sam34_putreg(0, priv->base + SAM_TC_CV_OFFSET); /* clear counter */
/* TC_CMR_WAVE - waveform mode /* TC_CMR_WAVE - waveform mode
* TC_CMR_WAVSEL_UPAUTO - reset on RC compare (interval timer) * TC_CMR_WAVSEL_UPAUTO - reset on RC compare (interval timer)
* TC_CMR_TCCLKS_TIMERCLOCK5 = SCLK * TC_CMR_TCCLKS_TIMERCLOCK5 = SCLK
*/ */
mr_val |= (TC_CMR_WAVE + TC_CMR_WAVSEL_UPAUTO + TC_CMR_TCCLKS_TIMERCLOCK5); mr_val = (TC_CMR_WAVE + TC_CMR_WAVSEL_UPAUTO + TC_CMR_TCCLKS_TIMERCLOCK5);
sam34_putreg(mr_val, priv->base + SAM_TC_CMR_OFFSET); sam34_putreg(mr_val, priv->base + SAM_TC_CMR_OFFSET);
sam34_putreg(priv->clkticks, priv->base + SAM_TC_RC_OFFSET); /* Set interval */ sam34_putreg(priv->clkticks, priv->base + SAM_TC_RC_OFFSET); /* Set interval */
@ -381,7 +379,7 @@ static int sam34_stop(FAR struct timer_lowerhalf_s *lower)
tcvdbg("Entry\n"); tcvdbg("Entry\n");
DEBUGASSERT(priv); DEBUGASSERT(priv);
if(!priv->started) if (!priv->started)
{ {
return -EINVAL; return -EINVAL;
} }
@ -430,7 +428,7 @@ static int sam34_getstatus(FAR struct timer_lowerhalf_s *lower,
if (priv->handler) if (priv->handler)
{ {
status->flags |= TCFLAGS_CAPTURE; status->flags |= TCFLAGS_HANDLER;
} }
/* Return the actual timeout is milliseconds */ /* Return the actual timeout is milliseconds */
@ -440,7 +438,7 @@ static int sam34_getstatus(FAR struct timer_lowerhalf_s *lower,
/* Get the time remaining until the timer expires (in microseconds) */ /* Get the time remaining until the timer expires (in microseconds) */
elapsed = sam34_getreg(priv->base + SAM_TC_CV_OFFSET); elapsed = sam34_getreg(priv->base + SAM_TC_CV_OFFSET);
status->timeleft = (priv->timeout * elapsed) / (priv->clkticks + 1); /* TODO - check on this +1 */ status->timeleft = ((uint64_t)priv->timeout * elapsed) / (priv->clkticks + 1); /* TODO - check on this +1 */
tcvdbg(" flags : %08x\n", status->flags); tcvdbg(" flags : %08x\n", status->flags);
tcvdbg(" timeout : %d\n", status->timeout); tcvdbg(" timeout : %d\n", status->timeout);
@ -470,6 +468,12 @@ static int sam34_settimeout(FAR struct timer_lowerhalf_s *lower,
FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower; FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower;
DEBUGASSERT(priv); DEBUGASSERT(priv);
if (priv->started)
{
return -EPERM;
}
tcvdbg("Entry: timeout=%d\n", timeout); tcvdbg("Entry: timeout=%d\n", timeout);
/* Can this timeout be represented? */ /* Can this timeout be represented? */
@ -486,21 +490,17 @@ static int sam34_settimeout(FAR struct timer_lowerhalf_s *lower,
timeout = (1000000ULL * priv->clkticks) / TC_FCLK; /* Truncated timeout */ timeout = (1000000ULL * priv->clkticks) / TC_FCLK; /* Truncated timeout */
priv->adjustment = priv->timeout - timeout; /* Truncated time to be added to next interval (dither) */ priv->adjustment = priv->timeout - timeout; /* Truncated time to be added to next interval (dither) */
tcvdbg("fwdt=%d reload=%d timout=%d, adjustment=%d\n", tcvdbg("fclk=%d clkticks=%d timout=%d, adjustment=%d\n",
TC_FCLK, reload, priv->timeout, priv->adjustment); TC_FCLK, priv->clkticks, priv->timeout, priv->adjustment);
/* Don't commit to MR register until started! */
return OK; return OK;
} }
/**************************************************************************** /****************************************************************************
* Name: sam34_capture * Name: sam34_sethandler
* *
* Description: * Description:
* Don't reset on timer timeout; instead, call this user provider * Call this user provided timeout handler.
* timeout handler. NOTE: Providing handler==NULL will restore the reset
* behavior.
* *
* Input Parameters: * Input Parameters:
* lower - A pointer the publicly visible representation of the "lower-half" * lower - A pointer the publicly visible representation of the "lower-half"
@ -511,13 +511,12 @@ static int sam34_settimeout(FAR struct timer_lowerhalf_s *lower,
* *
* Returned Values: * Returned Values:
* The previous timer expiration function pointer or NULL is there was * The previous timer expiration function pointer or NULL is there was
* no previous function pointer, i.e., if the previous behavior was * no previous function pointer.
* reset-on-expiration (NULL is also returned if an error occurs).
* *
****************************************************************************/ ****************************************************************************/
static tccb_t sam34_capture(FAR struct timer_lowerhalf_s *lower, static tccb_t sam34_sethandler(FAR struct timer_lowerhalf_s *lower,
tccb_t handler) tccb_t handler)
{ {
FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower; FAR struct sam34_lowerhalf_s *priv = (FAR struct sam34_lowerhalf_s *)lower;
irqstate_t flags; irqstate_t flags;