RT measurements unit added.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/kernel_3_dev@6036 35acf78f-673a-0410-8e92-d51de3d6d3f4

3 files changed, 210 insertions, 1 deletions

diff --git a/os/kernel/src/chrt.c b/os/kernel/src/chrt.c
new file mode 100644
index 000000000..a63ce9e32
--- /dev/null
+++ b/os/kernel/src/chrt.c
@@ -0,0 +1,206 @@
+/*

+    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,

+                 2011,2012,2013 Giovanni Di Sirio.

+

+    This file is part of ChibiOS/RT.

+

+    ChibiOS/RT is free software; you can redistribute it and/or modify

+    it under the terms of the GNU General Public License as published by

+    the Free Software Foundation; either version 3 of the License, or

+    (at your option) any later version.

+

+    ChibiOS/RT is distributed in the hope that it will be useful,

+    but WITHOUT ANY WARRANTY; without even the implied warranty of

+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+    GNU General Public License for more details.

+

+    You should have received a copy of the GNU General Public License

+    along with this program.  If not, see <http://www.gnu.org/licenses/>.

+*/

+

+/**

+ * @file    chvt.c

+ * @brief   Real Time Counter and Measurement module code.

+ *

+ * @addtogroup realtime_counter

+ * @details Realtime Counter APIs and services.

+ *

+ *          <h2>Operation mode</h2>

+ *          The realtime counter is a fast HW counter that counts upward at

+ *          regular intervals. This counted can be used for small and accurate

+ *          delays, time stamp and time measurement.

+ *

+ *          <h2>Notes</h2>

+ *          On those architectures where such a counter is not implemented

+ *          the system time counter is used instead. Of course the system

+ *          time counter usually has a much lower resolution than a real

+ *          HW counter.

+ * @{

+ */

+

+#include "ch.h"

+

+#if CH_CFG_USE_RT || defined(__DOXYGEN__)

+

+/*===========================================================================*/

+/* Module local definitions.                                                 */

+/*===========================================================================*/

+

+/*===========================================================================*/

+/* Module exported variables.                                                */

+/*===========================================================================*/

+

+/*===========================================================================*/

+/* Module local types.                                                       */

+/*===========================================================================*/

+

+/*===========================================================================*/

+/* Module local variables.                                                   */

+/*===========================================================================*/

+

+/**

+ * @brief   Subsystem calibration value.

+ */

+static rtcnt_t measurement_offset;

+

+/*===========================================================================*/

+/* Module local functions.                                                   */

+/*===========================================================================*/

+

+/*===========================================================================*/

+/* Module exported functions.                                                */

+/*===========================================================================*/

+

+/**

+ * @brief   Initializes the realtime counter unit.

+ *

+ * @init

+ */

+void _rt_init(void) {

+  time_measurement_t tm;

+

+  /* Time Measurement subsystem calibration, it does a null measurement

+     and calculates the call overhead which is subtracted to real

+     measurements.*/

+  measurement_offset = 0;

+  chRTTimeMeasurementObjectInit(&tm);

+  chRTTimeMeasurementStartX(&tm);

+  chRTTimeMeasurementStopX(&tm);

+  measurement_offset = tm.last;

+}

+

+/**

+ * @brief   Realtime window test.

+ * @details This function verifies if the current realtime counter value

+ *          lies within the specified range or not. The test takes care

+ *          of the realtime counter wrapping to zero on overflow.

+ * @note    When start==end then the function returns always true because the

+ *          whole time range is specified.

+ * @note    This function can be called from any context.

+ *

+ * @par Example 1

+ * Example of a guarded loop using the realtime counter. The loop implements

+ * a timeout after one second.

+ * @code

+ *   rtcnt_t start = chRTGetCounterValue();

+ *   rtcnt_t timeout  = start + S2RTC(RTCCLK, 1);

+ *   while (my_condition) {

+ *     if (!chRTIsCounterWithin(start, timeout)

+ *       return TIMEOUT;

+ *     // Do something.

+ *   }

+ *   // Continue.

+ * @endcode

+ *

+ * @par Example 2

+ * Example of a loop that lasts exactly 50 microseconds.

+ * @code

+ *   rtcnt_t start = chRTGetCounterValue();

+ *   rtcnt_t timeout  = start + US2RTC(RTCCLK, 50);

+ *   while (chRTIsCounterWithin(start, timeout)) {

+ *     // Do something.

+ *   }

+ *   // Continue.

+ * @endcode

+ *

+ * @param[in] start     the start of the time window (inclusive)

+ * @param[in] end       the end of the time window (non inclusive)

+ * @retval true         current time within the specified time window.

+ * @retval false        current time not within the specified time window.

+ *

+ * @special

+ */

+bool chRTIsCounterWithin(rtcnt_t start, rtcnt_t end) {

+  rtcnt_t now = chRTGetCounterValueX();

+

+  return end > start ? (now >= start) && (now < end) :

+                       (now >= start) || (now < end);

+}

+

+/**

+ * @brief   Polled delay.

+ * @note    The real delay is always few cycles in excess of the specified

+ *          value.

+ * @note    This function can be called from any context.

+ *

+ * @param[in] cycles    number of cycles

+ *

+ * @special

+ */

+void chRTPolledDelay(rtcnt_t cycles) {

+  rtcnt_t start = chRTGetCounterValueX();

+  rtcnt_t end  = start + cycles;

+  while (chRTIsCounterWithin(start, end))

+    ;

+}

+

+/**

+ * @brief   Initializes a @p TimeMeasurement object.

+ *

+ * @param[out] tmp      pointer to a @p TimeMeasurement structure

+ *

+ * @init

+ */

+void chRTTimeMeasurementObjectInit(time_measurement_t *tmp) {

+

+  tmp->last  = (rtcnt_t)0;

+  tmp->worst = (rtcnt_t)0;

+  tmp->best  = (rtcnt_t)-1;

+}

+

+/**

+ * @brief   Starts a measurement.

+ * @pre     The @p time_measurement_t structure must be initialized.

+ * @note    This function can be invoked from any context.

+ *

+ * @param[in,out] tmp   pointer to a @p TimeMeasurement structure

+ *

+ * @special

+ */

+NOINLINE void chRTTimeMeasurementStartX(time_measurement_t *tmp) {

+

+  tmp->last = chRTGetCounterValueX();

+}

+

+/**

+ * @brief   Stops a measurement.

+ * @pre     The @p time_measurement_t structure must be initialized.

+ * @note    This function can be invoked from any context.

+ *

+ * @param[in,out] tmp   pointer to a @p time_measurement_t structure

+ *

+ * @special

+ */

+NOINLINE void chRTTimeMeasurementStopX(time_measurement_t *tmp) {

+

+  rtcnt_t now = chRTGetCounterValueX();

+  tmp->last = now - tmp->last - measurement_offset;

+  if (tmp->last > tmp->worst)

+    tmp->worst = tmp->last;

+  else if (tmp->last < tmp->best)

+    tmp->best = tmp->last;

+}

+

+#endif /* CH_CFG_USE_RT */

+

+/** @} */

diff --git a/os/kernel/src/chsys.c b/os/kernel/src/chsys.c
index 4a67c7042..91277dc60 100644
--- a/os/kernel/src/chsys.c
+++ b/os/kernel/src/chsys.c
@@ -105,6 +105,9 @@ void chSysInit(void) {
   port_init();

   _scheduler_init();

   _vt_init();

+#if CH_CFG_USE_RT

+  _rt_init();

+#endif

 #if CH_CFG_USE_MEMCORE

   _core_init();

 #endif

diff --git a/os/kernel/src/chthreads.c b/os/kernel/src/chthreads.c
index 9017a59b7..b707b4562 100644
--- a/os/kernel/src/chthreads.c
+++ b/os/kernel/src/chthreads.c
@@ -327,7 +327,7 @@ void chThdSleep(systime_t time) {
 void chThdSleepUntil(systime_t time) {

 

   chSysLock();

-  if ((time -= chVTGetSystemTimeI()) > 0)

+  if ((time -= chVTGetSystemTimeX()) > 0)

     chThdSleepS(time);

   chSysUnlock();

 }