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Posted to commits@nuttx.apache.org by gn...@apache.org on 2020/02/15 13:18:29 UTC
[incubator-nuttx] 02/04: Reimplement arch alarm timer on top of
oneshot driver framework
This is an automated email from the ASF dual-hosted git repository.
gnutt pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/incubator-nuttx.git
commit d0d4b7a53178a5eb9e096d076c14584ebaab872c
Author: Xiang Xiao <xi...@xiaomi.com>
AuthorDate: Thu Feb 6 22:45:05 2020 +0800
Reimplement arch alarm timer on top of oneshot driver framework
The benefit include:
1. Simplify the implementation
2. Support both tick and tickless automatically
3. No time drift in tickless mode
4. Support critmon arch API automatically
---
arch/Kconfig | 2 +
arch/sim/src/Makefile | 10 +-
arch/sim/src/sim/up_critmon.c | 114 -------
.../sim/src/sim/{up_hostusleep.c => up_hosttime.c} | 49 ++-
arch/sim/src/sim/up_idle.c | 48 +--
arch/sim/src/sim/up_initialize.c | 13 -
arch/sim/src/sim/up_internal.h | 10 +-
arch/sim/src/sim/up_oneshot.c | 159 ++++++---
arch/sim/src/sim/up_tickless.c | 355 ---------------------
9 files changed, 187 insertions(+), 573 deletions(-)
diff --git a/arch/Kconfig b/arch/Kconfig
index 92a7d29..ce5bac9 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -72,6 +72,8 @@ config ARCH_SIM
select ARCH_HAVE_POWEROFF
select ARCH_HAVE_TESTSET
select ARCH_NOINTC
+ select ALARM_ARCH
+ select ONESHOT
select SERIAL_CONSOLE
---help---
Linux/Cywgin user-mode simulation.
diff --git a/arch/sim/src/Makefile b/arch/sim/src/Makefile
index 96a7078..5204949 100644
--- a/arch/sim/src/Makefile
+++ b/arch/sim/src/Makefile
@@ -74,16 +74,12 @@ CSRCS += up_allocateheap.c
VPATH = sim
DEPPATH = $(patsubst %,--dep-path %,$(subst :, ,$(VPATH)))
-HOSTSRCS = up_hostusleep.c
+HOSTSRCS = up_hosttime.c
ifeq ($(CONFIG_STACK_COLORATION),y)
CSRCS += up_checkstack.c
endif
-ifeq ($(CONFIG_SCHED_TICKLESS),y)
- CSRCS += up_tickless.c
-endif
-
ifeq ($(CONFIG_SPINLOCK),y)
HOSTSRCS += up_testset.c
endif
@@ -113,10 +109,6 @@ ifeq ($(CONFIG_ONESHOT),y)
CSRCS += up_oneshot.c
endif
-ifeq ($(CONFIG_SCHED_CRITMONITOR),y)
- HOSTSRCS += up_critmon.c
-endif
-
ifeq ($(CONFIG_NX_LCDDRIVER),y)
CSRCS += up_lcd.c
else
diff --git a/arch/sim/src/sim/up_critmon.c b/arch/sim/src/sim/up_critmon.c
deleted file mode 100644
index 15671f2..0000000
--- a/arch/sim/src/sim/up_critmon.c
+++ /dev/null
@@ -1,114 +0,0 @@
-/************************************************************************************
- * arch/sim/src/sim/up_critmon.c
- *
- * Copyright (C) 2018 Gregory Nutt. All rights reserved.
- * Author: Gregory Nutt <gn...@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 <stdint.h>
-#include <time.h>
-
-/************************************************************************************
- * Pre-processor Definitions
- ************************************************************************************/
-
-#undef USE_CLOCK /* Too slow */
-#define USE_CLOCK_GETTIME 1 /* Better */
-
-/* From nuttx/clock.h */
-
-#define NSEC_PER_SEC 1000000000
-
-/* From fixedmath.h */
-
-#define b32ONE 0x0000000100000000 /* 1 */
-#define b32toi(a) ((a) >> 32) /* Conversion to integer */
-#define itob32(i) (((b32_t)(i)) << 32) /* Conversion from integer */
-#define b32frac(a) ((a) & 0x00000000ffffffff) /* Take fractional part */
-
-/************************************************************************************
- * Private Types
- ************************************************************************************/
-
-/* From fixedmath.h */
-
-typedef int64_t b32_t;
-
-/************************************************************************************
- * Private Data
- ************************************************************************************/
-
-/************************************************************************************
- * Public Functions
- ************************************************************************************/
-
-/************************************************************************************
- * Name: up_critmon_gettime
- ************************************************************************************/
-
-#if defined(USE_CLOCK)
-uint32_t up_critmon_gettime(void)
-{
- return (uint32_t)clock() + 1; /* Avoid returning zero which means clock-not-ready */
-}
-#else /* USE_CLOCK_GETTIME */
-uint32_t up_critmon_gettime(void)
-{
- struct timespec ts;
- clock_gettime(CLOCK_MONOTONIC, &ts);
- return (uint32_t)ts.tv_nsec;
-}
-#endif
-
-/************************************************************************************
- * Name: up_critmon_gettime
- ************************************************************************************/
-
-#if defined(USE_CLOCK)
-void up_critmon_convert(uint32_t elapsed, struct timespec *ts)
-{
- b32_t b32elapsed;
-
- b32elapsed = itob32(elapsed) / CLOCKS_PER_SEC;
- ts->tv_sec = b32toi(b32elapsed);
- ts->tv_nsec = NSEC_PER_SEC * b32frac(b32elapsed) / b32ONE;
-}
-#else /* USE_CLOCK_GETTIME */
-void up_critmon_convert(uint32_t elapsed, struct timespec *ts)
-{
- ts->tv_sec = 0;
- ts->tv_nsec = elapsed;
-}
-#endif
diff --git a/arch/sim/src/sim/up_hostusleep.c b/arch/sim/src/sim/up_hosttime.c
similarity index 67%
rename from arch/sim/src/sim/up_hostusleep.c
rename to arch/sim/src/sim/up_hosttime.c
index a36e83e..cf2be0b 100644
--- a/arch/sim/src/sim/up_hostusleep.c
+++ b/arch/sim/src/sim/up_hosttime.c
@@ -1,5 +1,5 @@
/****************************************************************************
- * arch/sim/src/sim/up_hostusleep.c
+ * arch/sim/src/sim/up_hosttime.c
*
* Copyright (C) 2008 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gn...@nuttx.org>
@@ -37,6 +37,9 @@
* Included Files
****************************************************************************/
+#include <stdbool.h>
+#include <stdint.h>
+#include <time.h>
#include <unistd.h>
/****************************************************************************
@@ -44,10 +47,48 @@
****************************************************************************/
/****************************************************************************
- * Name: up_hostusleep
+ * Name: host_gettime
****************************************************************************/
-int up_hostusleep(unsigned int usec)
+uint64_t host_gettime(bool rtc)
{
- return usleep(usec);
+ struct timespec tp;
+
+ clock_gettime(rtc ? CLOCK_REALTIME : CLOCK_MONOTONIC, &tp);
+ return 1000000000ull * tp.tv_sec + tp.tv_nsec;
+}
+
+/****************************************************************************
+ * Name: host_settime
+ ****************************************************************************/
+
+void host_settime(bool rtc, uint64_t nsec)
+{
+ struct timespec tp;
+
+ tp.tv_sec = nsec / 1000000000;
+ tp.tv_nsec = nsec - 1000000000 * tp.tv_sec;
+ clock_settime(rtc ? CLOCK_REALTIME : CLOCK_MONOTONIC, &tp);
+}
+
+/****************************************************************************
+ * Name: host_sleepuntil
+ ****************************************************************************/
+
+void host_sleepuntil(uint64_t nsec)
+{
+ static uint64_t base;
+ uint64_t now;
+
+ now = host_gettime(false);
+ if (base == 0)
+ {
+ base = now;
+ }
+ now -= base;
+
+ if (nsec > now + 1000)
+ {
+ usleep((nsec - now) / 1000);
+ }
}
diff --git a/arch/sim/src/sim/up_idle.c b/arch/sim/src/sim/up_idle.c
index 27bfa7e..64cf774 100644
--- a/arch/sim/src/sim/up_idle.c
+++ b/arch/sim/src/sim/up_idle.c
@@ -72,16 +72,21 @@
void up_idle(void)
{
-#ifdef CONFIG_SCHED_TICKLESS
- /* Driver the simulated interval timer */
+#ifdef CONFIG_PM
+ static enum pm_state_e state = PM_NORMAL;
+ enum pm_state_e newstate;
- up_timer_update();
-#else
- /* If the system is idle, then process "fake" timer interrupts.
- * Hopefully, something will wake up.
- */
+ /* Fake some power management stuff for testing purposes */
- nxsched_process_timer();
+ newstate = pm_checkstate(PM_IDLE_DOMAIN);
+ if (newstate != state)
+ {
+ if (pm_changestate(PM_IDLE_DOMAIN, newstate) == OK)
+ {
+ state = newstate;
+ pwrinfo("IDLE: switching to new state %i\n", state);
+ }
+ }
#endif
#ifdef USE_DEVCONSOLE
@@ -106,30 +111,9 @@ void up_idle(void)
up_rptun_loop();
#endif
-#ifdef CONFIG_PM
- /* Fake some power management stuff for testing purposes */
-
- {
- static enum pm_state_e state = PM_NORMAL;
- enum pm_state_e newstate;
-
- newstate = pm_checkstate(PM_IDLE_DOMAIN);
- if (newstate != state)
- {
- if (pm_changestate(PM_IDLE_DOMAIN, newstate) == OK)
- {
- state = newstate;
- pwrinfo("IDLE: switching to new state %i\n", state);
- }
- }
- }
-#endif
-
-#ifdef CONFIG_SIM_WALLTIME
- /* Wait a bit so that the nxsched_process_timer() is called close to the
- * correct rate.
- */
+#ifdef CONFIG_ONESHOT
+ /* Driver the simulated interval timer */
- up_hostusleep(1000000 / CLK_TCK);
+ up_timer_update();
#endif
}
diff --git a/arch/sim/src/sim/up_initialize.c b/arch/sim/src/sim/up_initialize.c
index a967e71..bbd1122 100644
--- a/arch/sim/src/sim/up_initialize.c
+++ b/arch/sim/src/sim/up_initialize.c
@@ -296,16 +296,3 @@ void up_initialize(void)
up_init_smartfs();
#endif
}
-
-/****************************************************************************
- * Function: up_timer_initialize
- *
- * Description:
- * This function is called during start-up to initialize
- * the timer hardware.
- *
- ****************************************************************************/
-
-void up_timer_initialize(void)
-{
-}
diff --git a/arch/sim/src/sim/up_internal.h b/arch/sim/src/sim/up_internal.h
index a7fd589..660d80f 100644
--- a/arch/sim/src/sim/up_internal.h
+++ b/arch/sim/src/sim/up_internal.h
@@ -225,9 +225,11 @@ volatile spinlock_t g_cpu_paused[CONFIG_SMP_NCPUS] SP_SECTION;
int up_setjmp(xcpt_reg_t *jb);
void up_longjmp(xcpt_reg_t *jb, int val) noreturn_function;
-/* up_hostusleep.c **********************************************************/
+/* up_hosttime.c ************************************************************/
-int up_hostusleep(unsigned int usec);
+uint64_t host_gettime(bool rtc);
+void host_settime(bool rtc, uint64_t nsec);
+void host_sleepuntil(uint64_t nsec);
/* up_simsmp.c **************************************************************/
@@ -241,9 +243,9 @@ void sim_cpu0_start(void);
void up_cpu_started(void);
#endif
-/* up_tickless.c ************************************************************/
+/* up_oneshot.c *************************************************************/
-#ifdef CONFIG_SCHED_TICKLESS
+#ifdef CONFIG_ONESHOT
void up_timer_update(void);
#endif
diff --git a/arch/sim/src/sim/up_oneshot.c b/arch/sim/src/sim/up_oneshot.c
index 9beef16..1c31ea1 100644
--- a/arch/sim/src/sim/up_oneshot.c
+++ b/arch/sim/src/sim/up_oneshot.c
@@ -39,16 +39,20 @@
#include <nuttx/config.h>
-#include <stdint.h>
-#include <time.h>
#include <limits.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
+#include <queue.h>
-#include <nuttx/wdog.h>
+#include <nuttx/nuttx.h>
+#include <nuttx/arch.h>
+#include <nuttx/clock.h>
#include <nuttx/kmalloc.h>
#include <nuttx/timers/oneshot.h>
+#include <nuttx/timers/arch_alarm.h>
+
+#include "up_internal.h"
/****************************************************************************
* Private Types
@@ -68,7 +72,9 @@ struct sim_oneshot_lowerhalf_s
/* Private lower half data follows */
- WDOG_ID wdog; /* Simulates oneshot timer */
+ sq_entry_t link;
+ struct timespec alarm;
+
oneshot_callback_t callback; /* internal handler that receives callback */
FAR void *arg; /* Argument that is passed to the handler */
};
@@ -77,7 +83,7 @@ struct sim_oneshot_lowerhalf_s
* Private Function Prototypes
****************************************************************************/
-static void sim_oneshot_handler(int argc, wdparm_t arg1, ...);
+static void sim_process_tick(sq_entry_t *entry);
static int sim_max_delay(FAR struct oneshot_lowerhalf_s *lower,
FAR struct timespec *ts);
@@ -86,11 +92,16 @@ static int sim_start(FAR struct oneshot_lowerhalf_s *lower,
FAR const struct timespec *ts);
static int sim_cancel(FAR struct oneshot_lowerhalf_s *lower,
FAR struct timespec *ts);
+static int sim_current(FAR struct oneshot_lowerhalf_s *lower,
+ FAR struct timespec *ts);
/****************************************************************************
* Private Data
****************************************************************************/
+static struct timespec g_current;
+static sq_queue_t g_oneshot_list;
+
/* Lower half operations */
static const struct oneshot_operations_s g_oneshot_ops =
@@ -98,6 +109,7 @@ static const struct oneshot_operations_s g_oneshot_ops =
.max_delay = sim_max_delay,
.start = sim_start,
.cancel = sim_cancel,
+ .current = sim_current,
};
/****************************************************************************
@@ -105,35 +117,35 @@ static const struct oneshot_operations_s g_oneshot_ops =
****************************************************************************/
/****************************************************************************
- * Name: sim_oneshot_handler
+ * Name: sim_process_tick
*
* Description:
* Timer expiration handler
*
* Input Parameters:
- * arg - Should be the same argument provided when sim_oneshot_start()
- * was called.
+ * entry - Point to the link field of sim_oneshot_lowerhalf_s.
*
* Returned Value:
* None
*
****************************************************************************/
-static void sim_oneshot_handler(int argc, wdparm_t arg1, ...)
+static void sim_process_tick(sq_entry_t *entry)
{
FAR struct sim_oneshot_lowerhalf_s *priv =
- (FAR struct sim_oneshot_lowerhalf_s *)arg1;
+ container_of(entry, struct sim_oneshot_lowerhalf_s, link);
oneshot_callback_t callback;
FAR void *cbarg;
- DEBUGASSERT(argc == 1 && priv != NULL);
-
- /* Perhaps the callback was nullified in a race condition with
- * sim_cancel?
- */
+ DEBUGASSERT(priv != NULL);
if (priv->callback)
{
+ if (clock_timespec_compare(&priv->alarm, &g_current) > 0)
+ {
+ return; /* Alarm doesn't expire yet */
+ }
+
/* Sample and nullify BEFORE executing callback (in case the callback
* restarts the oneshot).
*/
@@ -153,7 +165,7 @@ static void sim_oneshot_handler(int argc, wdparm_t arg1, ...)
* Name: sim_max_delay
*
* Description:
- * Determine the maximum delay of the one-shot timer (in microseconds)
+ * Determine the maximum delay of the one-shot timer
*
* Input Parameters:
* lower An instance of the lower-half oneshot state structure. This
@@ -172,8 +184,8 @@ static int sim_max_delay(FAR struct oneshot_lowerhalf_s *lower,
{
DEBUGASSERT(lower != NULL && ts != NULL);
- ts->tv_sec = INT_MAX;
- ts->tv_nsec = 1000000000ul - 1;
+ ts->tv_sec = UINT_MAX;
+ ts->tv_nsec = NSEC_PER_SEC - 1;
return OK;
}
@@ -203,24 +215,15 @@ static int sim_start(FAR struct oneshot_lowerhalf_s *lower,
{
FAR struct sim_oneshot_lowerhalf_s *priv =
(FAR struct sim_oneshot_lowerhalf_s *)lower;
- clock_t ticks;
- int64_t nsec;
DEBUGASSERT(priv != NULL && callback != NULL && ts != NULL);
- /* Convert time to ticks */
-
- nsec = (int64_t)ts->tv_sec * NSEC_PER_SEC +
- (int64_t)ts->tv_nsec;
- ticks = (clock_t)((nsec + NSEC_PER_TICK - 1) / NSEC_PER_TICK);
-
- /* Save the callback information and start the timer */
+ clock_timespec_add(&g_current, ts, &priv->alarm);
priv->callback = callback;
priv->arg = arg;
- return wd_start(priv->wdog, ticks, (wdentry_t)sim_oneshot_handler,
- 1, (wdparm_t)priv);
+ return OK;
}
/****************************************************************************
@@ -252,17 +255,46 @@ static int sim_cancel(FAR struct oneshot_lowerhalf_s *lower,
{
FAR struct sim_oneshot_lowerhalf_s *priv =
(FAR struct sim_oneshot_lowerhalf_s *)lower;
- int ret;
- DEBUGASSERT(priv != NULL);
+ DEBUGASSERT(priv != NULL && ts != NULL);
- /* Cancel the timer */
+ clock_timespec_subtract(&priv->alarm, &g_current, ts);
- ret = wd_cancel(priv->wdog);
priv->callback = NULL;
priv->arg = NULL;
- return ret;
+ return OK;
+}
+
+/****************************************************************************
+ * Name: sim_current
+ *
+ * Description:
+ * Get the current time.
+ *
+ * Input Parameters:
+ * lower Caller allocated instance of the oneshot state structure. This
+ * structure must have been previously initialized via a call to
+ * oneshot_initialize();
+ * ts The location in which to return the current time. A time of zero
+ * is returned for the initialization moment.
+ *
+ * Returned Value:
+ * Zero (OK) is returned on success, a negated errno value is returned on
+ * any failure.
+ *
+ ****************************************************************************/
+
+static int sim_current(FAR struct oneshot_lowerhalf_s *lower,
+ FAR struct timespec *ts)
+{
+ FAR struct sim_oneshot_lowerhalf_s *priv =
+ (FAR struct sim_oneshot_lowerhalf_s *)lower;
+
+ DEBUGASSERT(priv != NULL && ts != NULL);
+
+ *ts = g_current;
+ return OK;
}
/****************************************************************************
@@ -306,17 +338,60 @@ FAR struct oneshot_lowerhalf_s *oneshot_initialize(int chan,
/* Initialize the lower-half driver structure */
+ sq_addlast(&priv->link, &g_oneshot_list);
priv->lh.ops = &g_oneshot_ops;
- /* Initialize the contained watchdog timer */
+ return &priv->lh;
+}
+
+/****************************************************************************
+ * Function: up_timer_initialize
+ *
+ * Description:
+ * This function is called during start-up to initialize
+ * the timer hardware.
+ *
+ ****************************************************************************/
+
+void up_timer_initialize(void)
+{
+ up_alarm_set_lowerhalf(oneshot_initialize(0, 0));
+}
+
+/****************************************************************************
+ * Name: up_timer_update
+ *
+ * Description:
+ * Called from the IDLE loop to fake one timer tick.
+ *
+ * Input Parameters:
+ * None
+ *
+ * Returned Value:
+ * None
+ *
+ ****************************************************************************/
+
+void up_timer_update(void)
+{
+ static const struct timespec tick =
+ {
+ .tv_sec = 0,
+ .tv_nsec = NSEC_PER_TICK,
+ };
+ FAR sq_entry_t *entry;
+
+ clock_timespec_add(&g_current, &tick, &g_current);
+
+#ifdef CONFIG_SIM_WALLTIME
+ /* Wait a bit so that the timing is close to the correct rate. */
- priv->wdog = wd_create();
- if (priv->wdog == NULL)
+ host_sleepuntil(g_current.tv_nsec +
+ (uint64_t)g_current.tv_sec * NSEC_PER_SEC);
+#endif
+
+ for (entry = sq_peek(&g_oneshot_list); entry; entry = sq_next(entry))
{
- tmrerr("ERROR: Failed to create wdog\n");
- kmm_free(priv);
- return NULL;
+ sim_process_tick(entry);
}
-
- return &priv->lh;
}
diff --git a/arch/sim/src/sim/up_tickless.c b/arch/sim/src/sim/up_tickless.c
deleted file mode 100644
index 43752f4..0000000
--- a/arch/sim/src/sim/up_tickless.c
+++ /dev/null
@@ -1,355 +0,0 @@
-/****************************************************************************
- * arch/sim/src/sim/up_tickless.c
- *
- * Copyright (C) 2014, 2019 Gregory Nutt. All rights reserved.
- * Author: Gregory Nutt <gn...@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.
- *
- ****************************************************************************/
-
-/****************************************************************************
- * Tickless OS Support.
- *
- * When CONFIG_SCHED_TICKLESS is enabled, all support for timer interrupts
- * is suppressed and the platform specific code is expected to provide the
- * following custom functions.
- *
- * void sim_timer_initialize(void): Initializes the timer facilities.
- * Called early in the initialization sequence (by up_initialize()).
- * int up_timer_gettime(FAR struct timespec *ts): Returns the current
- * time from the platform specific time source.
- * int up_timer_cancel(void): Cancels the interval timer.
- * int up_timer_start(FAR const struct timespec *ts): Start (or re-starts)
- * the interval timer.
- *
- * The RTOS will provide the following interfaces for use by the platform-
- * specific interval timer implementation:
- *
- * void nxsched_timer_expiration(void): Called by the platform-specific
- * logic when the interval timer expires.
- *
- ****************************************************************************/
-
-/****************************************************************************
- * Included Files
- ****************************************************************************/
-
-#include <nuttx/config.h>
-
-#include <stdint.h>
-#include <stdbool.h>
-#include <time.h>
-
-#include <nuttx/arch.h>
-#include <nuttx/clock.h>
-
-#ifdef CONFIG_SCHED_TICKLESS
-
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-#if defined(CONFIG_SIM_WALLTIME) || defined(CONFIG_SIM_X11FB)
-/* TICK_USEC, the desired number of microseconds per clock tick (truncated) */
-
-# define TICK_USEC (USEC_PER_SEC / CLK_TCK)
-
-/* TICK_SEC, the integer number of seconds in the clock tick (truncated).
- * Should be zero.
- */
-
-# define TICK_SEC (TICK_USEC / USEC_PER_SEC)
-
-/* TICK_NSEC, the integer number of nanoseconds (in addition to the number of
- * seconds) in the clock tick.
- */
-
-# define USEC_REMAINDER (TICK_USEC - (TICK_SEC * USEC_PER_SEC))
-# define TICK_NSEC (USEC_REMAINDER * NSEC_PER_USEC)
-
-#else
-
-# define TICK_SEC 0
-# define TICK_NSEC NSEC_PER_TICK
-
-#endif
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-static struct timespec g_elapsed_time;
-static struct timespec g_interval_delay;
-static bool g_timer_active;
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Name: sim_timer_initialize
- *
- * Description:
- * Initializes all platform-specific timer facilities. This function is
- * called early in the initialization sequence by up_initialize().
- * On return, the current up-time should be available from
- * up_timer_gettime() and the interval timer is ready for use (but not
- * actively timing.
- *
- * Provided by platform-specific code and called from the architecture-
- * specific logic.
- *
- * Input Parameters:
- * None
- *
- * Returned Value:
- * None
- *
- * Assumptions:
- * Called early in the initialization sequence before any special
- * concurrency protections are required.
- *
- ****************************************************************************/
-
-void sim_timer_initialize(void)
-{
- g_elapsed_time.tv_sec = 0;
- g_elapsed_time.tv_nsec = 0;
- g_timer_active = false;
-}
-
-/****************************************************************************
- * Name: up_timer_gettime
- *
- * Description:
- * Return the elapsed time since power-up (or, more correctly, since
- * sim_timer_initialize() was called). This function is functionally
- * equivalent to:
- *
- * int clock_gettime(clockid_t clockid, FAR struct timespec *ts);
- *
- * when clockid is CLOCK_MONOTONIC.
- *
- * This function provides the basis for reporting the current time and
- * also is used to eliminate error build-up from small erros in interval
- * time calculations.
- *
- * Provided by platform-specific code and called from the RTOS base code.
- *
- * Input Parameters:
- * ts - Provides the location in which to return the up-time.
- *
- * Returned Value:
- * Zero (OK) is returned on success; a negated errno value is returned on
- * any failure.
- *
- * Assumptions:
- * Called from the normal tasking context. The implementation must
- * provide whatever mutual exclusion is necessary for correct operation.
- * This can include disabling interrupts in order to assure atomic register
- * operations.
- *
- ****************************************************************************/
-
-int up_timer_gettime(FAR struct timespec *ts)
-{
- ts->tv_sec = g_elapsed_time.tv_sec;
- ts->tv_nsec = g_elapsed_time.tv_nsec;
-
- return OK;
-}
-
-/****************************************************************************
- * Name: up_timer_cancel
- *
- * Description:
- * Cancel the interval timer and return the time remaining on the timer.
- * These two steps need to be as nearly atomic as possible.
- * nxsched_timer_expiration() will not be called unless the timer is
- * restarted with up_timer_start().
- *
- * If, as a race condition, the timer has already expired when this
- * function is called, then that pending interrupt must be cleared so
- * that up_timer_start() and the remaining time of zero should be
- * returned.
- *
- * Provided by platform-specific code and called from the RTOS base code.
- *
- * Input Parameters:
- * ts - Location to return the remaining time. Zero should be returned
- * if the timer is not active.
- *
- * Returned Value:
- * Zero (OK) is returned on success; a negated errno value is returned on
- * any failure.
- *
- * Assumptions:
- * May be called from interrupt level handling or from the normal tasking
- * level. Interrupts may need to be disabled internally to assure
- * non-reentrancy.
- *
- ****************************************************************************/
-
-#ifdef CONFIG_SCHED_TICKLESS
-int up_timer_cancel(FAR struct timespec *ts)
-{
- /* Return the time remaining on the simulated timer */
-
- if (g_timer_active)
- {
- ts->tv_sec = g_interval_delay.tv_sec;
- ts->tv_nsec = g_interval_delay.tv_nsec;
- }
- else
- {
- ts->tv_sec = 0;
- ts->tv_nsec = 0;
- }
-
- /* Disable and reset the simulated timer */
-
- g_interval_delay.tv_sec = 0;
- g_interval_delay.tv_nsec = 0;
- g_timer_active = false;
-
- return 0;
-}
-#endif
-
-/****************************************************************************
- * Name: up_timer_start
- *
- * Description:
- * Start the interval timer. nxsched_timer_expiration() will be
- * called at the completion of the timeout (unless up_timer_cancel
- * is called to stop the timing.
- *
- * Provided by platform-specific code and called from the RTOS base code.
- *
- * Input Parameters:
- * ts - Provides the time interval until nxsched_timer_expiration() is
- * called.
- *
- * Returned Value:
- * Zero (OK) is returned on success; a negated errno value is returned on
- * any failure.
- *
- * Assumptions:
- * May be called from interrupt level handling or from the normal tasking
- * level. Interrupts may need to be disabled internally to assure
- * non-reentrancy.
- *
- ****************************************************************************/
-
-#ifdef CONFIG_SCHED_TICKLESS
-int up_timer_start(FAR const struct timespec *ts)
-{
- g_interval_delay.tv_sec = ts->tv_sec;
- g_interval_delay.tv_nsec = ts->tv_nsec;
- g_timer_active = true;
-
- return 0;
-}
-#endif
-
-/****************************************************************************
- * Name: up_timer_update
- *
- * Description:
- * Called from the IDLE loop to fake one timer tick.
- *
- * Input Parameters:
- * None
- *
- * Returned Value:
- * None
- *
- ****************************************************************************/
-
-void up_timer_update(void)
-{
- /* Increment the elapsed time */
-
- g_elapsed_time.tv_nsec += TICK_NSEC;
- if (g_elapsed_time.tv_nsec >= NSEC_PER_SEC)
- {
- g_elapsed_time.tv_sec++;
- g_elapsed_time.tv_nsec -= NSEC_PER_SEC;
- }
-
- g_elapsed_time.tv_sec += TICK_SEC;
-
- /* Is the interval timer active? */
-
- if (g_timer_active)
- {
- /* Yes... decrement the interval timer */
-
- if (g_interval_delay.tv_sec < TICK_SEC)
- {
- /* No more seconds left... the timer has expired */
-
- g_timer_active = false;
- nxsched_timer_expiration();
- }
- else
- {
- /* Decrement seconds. May decrement to zero */
-
- g_interval_delay.tv_sec -= TICK_SEC;
-
- /* Decrement nanoseconds */
-
- if (g_interval_delay.tv_nsec >= TICK_NSEC)
- {
- g_interval_delay.tv_nsec -= TICK_NSEC;
- }
-
- /* Handle borrow from seconds */
-
- else if (g_interval_delay.tv_sec > 0)
- {
- g_interval_delay.tv_nsec += NSEC_PER_SEC;
- g_interval_delay.tv_sec--;
-
- g_interval_delay.tv_nsec -= TICK_NSEC;
- }
-
- /* Otherwise the timer has expired */
-
- else
- {
- g_timer_active = false;
- nxsched_timer_expiration();
- }
- }
- }
-}
-
-#endif /* CONFIG_SCHED_TICKLESS */