contrib/utils/utility.h

0001 /* ----------------------------------------------------------------------------
0002  *         SAM Software Package License
0003  * ----------------------------------------------------------------------------
0004  * Copyright (c) 2014, Atmel Corporation
0005  *
0006  * All rights reserved.
0007  *
0008  * Redistribution and use in source and binary forms, with or without
0009  * modification, are permitted provided that the following conditions are met:
0010  *
0011  * - Redistributions of source code must retain the above copyright notice,
0012  * this list of conditions and the disclaimer below.
0013  *
0014  * Atmel's name may not be used to endorse or promote products derived from
0015  * this software without specific prior written permission.
0016  *
0017  * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
0018  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
0019  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
0020  * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
0021  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
0022  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
0023  * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
0024  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
0025  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
0026  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
0027  * ----------------------------------------------------------------------------
0028  */
0029
0030 #ifndef UTILITY_H
0031 #define UTILITY_H
0032
0033 #include "chip.h"
0034
0035
0036
0037 #define RESET_CYCLE_COUNTER()  do { \
0038         CoreDebug->DEMCR = CoreDebug_DEMCR_TRCENA_Msk; \
0039         __DSB(); DWT->LAR = 0xC5ACCE55; __DSB(); \
0040         DWT->CTRL &= ~DWT_CTRL_CYCCNTENA_Msk; \
0041         DWT->CYCCNT = 0; \
0042         DWT->CTRL = DWT_CTRL_CYCCNTENA_Msk; \
0043     }while(0)
0044
0045 #define GET_CYCLE_COUNTER(x)                x=DWT->CYCCNT;
0046
0047 #define LockMutex(mut, timeout)             get_lock(&mut, 1, &timeout)
0048
0049 #define ReleaseMutex(mut)                   free_lock(&mut)
0050
0051 #define GetResource(mut, max, timeout)      get_lock(&mut, max, &timeout)
0052
0053 #define FreeResource(mut)                   free_lock(&mut)
0054
0055
0056 __STATIC_INLINE uint8_t Is_LockFree(volatile uint8_t *Lock_Variable)
0057 {
0058     /* return Variable value*/
0059     return __LDREXB(Lock_Variable);
0060
0061 }
0062
0063 __STATIC_INLINE uint8_t get_lock(volatile uint8_t *Lock_Variable, const uint8_t maxValue, volatile uint32_t *pTimeout)
0064 {
0065     while (*pTimeout)
0066     {
0067         if(__LDREXB(Lock_Variable) < maxValue)
0068         {
0069           /* Set the Variable */
0070           while( __STREXB(((*Lock_Variable) + 1), Lock_Variable) )
0071           {
0072             if(!(*pTimeout)--)
0073             {
0074               return 1;       // quit if timeout
0075             }
0076           }
0077           /* Memory access barrier */
0078           __DMB();
0079           TRACE_DEBUG("Mutex locked ");
0080           return 0;
0081         }
0082
0083         ((*pTimeout)--);
0084     }
0085     return 1;
0086 }
0087
0088
0089
0090 __STATIC_INLINE uint8_t free_lock(volatile uint8_t *Lock_Variable)
0091 {
0092     /* Memory access barrier Ensure memory operations completed before releasing lock  */
0093     __DSB();
0094     if(__LDREXB(Lock_Variable))
0095     {
0096       __STREXB( ((*Lock_Variable) - 1), Lock_Variable);
0097       TRACE_DEBUG("Mutex freed ");
0098       __DSB();
0099       __DMB(); // Ensure memory operations completed before
0100       return 0;
0101     }
0102     else
0103     {
0104       return 1;
0105     }
0106
0107
0108 }
0109
0110
0111 #endif /* UTILITY_H */