git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/kernel_3_dev@6035 35acf78f-673a-0410-8e92-d51de3d6d3f4

demos/ARMCM4-STM32F303-DISCOVERY/chconf.h

@@ -127,6 +127,16 @@
  */
 /*===========================================================================*/
 
+/**
+ * @brief   Realtime counter APIs.
+ * @details If enabled then the RT APIs are included in the kernel.
+ *
+ * @note    The default is @p TRUE.
+ */
+#if !defined(CH_CFG_USE_RT) || defined(__DOXYGEN__)
+#define CH_CFG_USE_RT                       TRUE
+#endif
+
 /**
  * @brief   Threads registry APIs.
  * @details If enabled then the registry APIs are included in the kernel.

os/kernel/include/ch.h

@@ -109,6 +109,7 @@ typedef struct thread thread_t;
 #include "chtypes.h"
 #include "chdebug.h"
 #include "chcore.h"
+#include "chrt.h"
 #include "chthreads.h"
 #include "chlists.h"
 #include "chsys.h"

os/kernel/include/chrt.h

@@ -0,0 +1,231 @@
+/*
+    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    chrt.h
+ * @brief   Real Time Counter and Measurement module macros and structures.
+ *
+ * @addtogroup rt_measurement
+ * @{
+ */
+
+#ifndef _CHRT_H_
+#define _CHRT_H_
+
+#if CH_CFG_USE_RT || defined(__DOXYGEN__)
+
+#define port_rt_get_counter_value() 0
+
+/*===========================================================================*/
+/* Module constants.                                                         */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module pre-compile time settings.                                         */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Derived constants and error checks.                                       */
+/*===========================================================================*/
+
+#if !CH_PORT_SUPPORTS_RT
+#error "the port layer does not support the realtime counter functionality"
+#endif
+
+/*===========================================================================*/
+/* Module data structures and types.                                         */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module macros.                                                            */
+/*===========================================================================*/
+/**
+ * @name    Time conversion utilities for the realtime counter
+ * @{
+ */
+/**
+ * @brief   Seconds to realtime counter.
+ * @details Converts from seconds to realtime counter cycles.
+ * @note    The result is rounded upward to the next tick boundary.
+ *
+ * @param[in] sec       number of seconds
+ * @return              The number of cycles.
+ *
+ * @api
+ */
+#define S2RTV(freq, sec) ((freq) * (sec))
+
+/**
+ * @brief   Milliseconds to realtime counter.
+ * @details Converts from milliseconds to realtime counter cycles.
+ * @note    The result is rounded upward to the next tick boundary.
+ *
+ * @param[in] msec      number of milliseconds
+ * @return              The number of cycles.
+ *
+ * @api
+ */
+#define MS2RTC(freq, msec) (rtcnt_t)((((freq) + 999UL) / 1000UL) * (msec))
+
+/**
+ * @brief   Microseconds to realtime counter.
+ * @details Converts from microseconds to realtime counter cycles.
+ * @note    The result is rounded upward to the next tick boundary.
+ *
+ * @param[in] usec      number of microseconds
+ * @return              The number of cycles.
+ *
+ * @api
+ */
+#define US2RTC(freq, usec) (rtcnt_t)((((freq) + 999999UL) / 1000000UL) * (usec))
+
+/**
+ * @brief   Realtime counter cycles to seconds.
+ * @details Converts from realtime counter cycles number to seconds.
+ *
+ * @param[in] n         number of cycles
+ * @return              The number of seconds.
+ *
+ * @api
+ */
+#define RTC2S(freq, n) (rtcnt_t)((n) / (freq))
+
+/**
+ * @brief   Realtime counter cycles to milliseconds.
+ * @details Converts from realtime counter cycles number to milliseconds.
+ *
+ * @param[in] n         number of cycles
+ * @return              The number of milliseconds.
+ *
+ * @api
+ */
+#define RTC2MS(freq, n) ((n) / ((freq) / 1000UL))
+
+/**
+ * @brief   Realtime counter cycles to microseconds.
+ * @details Converts from realtime counter cycles number to microseconds.
+ *
+ * @param[in] n         number of cycles
+ * @return              The number of microseconds.
+ *
+ * @api
+ */
+#define RTC2US(freq, n) ((n) / ((freq) / 1000000UL))
+/** @} */
+
+/*===========================================================================*/
+/* External declarations.                                                    */
+/*===========================================================================*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+#ifdef __cplusplus
+}
+#endif
+
+/*===========================================================================*/
+/* Module inline functions.                                                  */
+/*===========================================================================*/
+
+/**
+ * @brief   Returns the current value of the system real time counter.
+ * @note    This function can be called from any context.
+ *
+ * @return              The value of the system free running counter of
+ *                      type rtcnt_t.
+ *
+ * @special
+ */
+static inline rtcnt_t chRTGetCounterValue(void) {
+
+  return port_rt_get_counter_value();
+}
+
+/**
+ * @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(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(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
+ */
+static inline bool chRTIsCounterWithin(rtcnt_t start, rtcnt_t end) {
+  rtcnt_t now = chRTGetCounterValue();
+
+  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] ticks     number of ticks
+ *
+ * @special
+ */
+static inline void chRTPolledDelay(rtcnt_t ticks) {
+  rtcnt_t start = chRTGetCounterValue();
+  rtcnt_t timeout  = start + (ticks);
+  while (chRTIsCounterWithin(start, timeout))
+    ;
+}
+
+#endif /* CH_CFG_USE_RT */
+
+#endif /* _CHRT_H_ */
+
+/** @} */

os/ports/GCC/ARMCMx/chcore_v7m.h

@@ -73,6 +73,11 @@
 #endif
 /** @} */
 
+/**
+ * @brief   This port supports a realtime counter.
+ */
+#define CH_PORT_SUPPORTS_RT             TRUE
+
 /**
  * @brief   Disabled value for BASEPRI register.
  */

os/ports/GCC/ARMCMx/chtypes.h

@@ -34,6 +34,7 @@
 #include <stdbool.h>
 
 typedef bool            bool_t;         /**< Fast boolean type.             */
+typedef uint32_t        rtcnt_t;        /**< Realtime counter.              */
 typedef uint32_t        syssts_t;       /**< System status word.            */
 typedef uint8_t         tmode_t;        /**< Thread flags.                  */
 typedef uint8_t         tstate_t;       /**< Thread state.                  */