mbed official / mbed-dev

mbed library sources. Supersedes mbed-src.

Dependents:   Nucleo_Hello_Encoder BLE_iBeaconScan AM1805_DEMO DISCO-F429ZI_ExportTemplate1 ... more

targets/TARGET_Maxim/TARGET_MAX32620C/mxc/mxc_lock.c@189:f392fc9709a3, 2019-02-20 (annotated)

Committer:
AnnaBridge
Date:
Wed Feb 20 22:31:08 2019 +0000
Revision:
189:f392fc9709a3
Parent:
186:707f6e361f3e 
mbed library release version 165

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Anna Bridge 186:707f6e361f3e 1 /**
Anna Bridge 186:707f6e361f3e 2 * @file
Anna Bridge 186:707f6e361f3e 3 * @brief Exclusive access lock utility functions.
Anna Bridge 186:707f6e361f3e 4 */
Anna Bridge 186:707f6e361f3e 5 /* ****************************************************************************
Anna Bridge 186:707f6e361f3e 6 * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
Anna Bridge 186:707f6e361f3e 7 *
Anna Bridge 186:707f6e361f3e 8 * Permission is hereby granted, free of charge, to any person obtaining a
Anna Bridge 186:707f6e361f3e 9 * copy of this software and associated documentation files (the "Software"),
Anna Bridge 186:707f6e361f3e 10 * to deal in the Software without restriction, including without limitation
Anna Bridge 186:707f6e361f3e 11 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
Anna Bridge 186:707f6e361f3e 12 * and/or sell copies of the Software, and to permit persons to whom the
Anna Bridge 186:707f6e361f3e 13 * Software is furnished to do so, subject to the following conditions:
Anna Bridge 186:707f6e361f3e 14 *
Anna Bridge 186:707f6e361f3e 15 * The above copyright notice and this permission notice shall be included
Anna Bridge 186:707f6e361f3e 16 * in all copies or substantial portions of the Software.
Anna Bridge 186:707f6e361f3e 17 *
Anna Bridge 186:707f6e361f3e 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
Anna Bridge 186:707f6e361f3e 19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
Anna Bridge 186:707f6e361f3e 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
Anna Bridge 186:707f6e361f3e 21 * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
Anna Bridge 186:707f6e361f3e 22 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
Anna Bridge 186:707f6e361f3e 23 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
Anna Bridge 186:707f6e361f3e 24 * OTHER DEALINGS IN THE SOFTWARE.
Anna Bridge 186:707f6e361f3e 25 *
Anna Bridge 186:707f6e361f3e 26 * Except as contained in this notice, the name of Maxim Integrated
Anna Bridge 186:707f6e361f3e 27 * Products, Inc. shall not be used except as stated in the Maxim Integrated
Anna Bridge 186:707f6e361f3e 28 * Products, Inc. Branding Policy.
Anna Bridge 186:707f6e361f3e 29 *
Anna Bridge 186:707f6e361f3e 30 * The mere transfer of this software does not imply any licenses
Anna Bridge 186:707f6e361f3e 31 * of trade secrets, proprietary technology, copyrights, patents,
Anna Bridge 186:707f6e361f3e 32 * trademarks, maskwork rights, or any other form of intellectual
Anna Bridge 186:707f6e361f3e 33 * property whatsoever. Maxim Integrated Products, Inc. retains all
Anna Bridge 186:707f6e361f3e 34 * ownership rights.
Anna Bridge 186:707f6e361f3e 35 *
Anna Bridge 186:707f6e361f3e 36 * $Date: 2017-02-14 18:16:40 -0600 (Tue, 14 Feb 2017) $
Anna Bridge 186:707f6e361f3e 37 * $Revision: 26426 $
Anna Bridge 186:707f6e361f3e 38 *
Anna Bridge 186:707f6e361f3e 39 *************************************************************************** */
Anna Bridge 186:707f6e361f3e 40
Anna Bridge 186:707f6e361f3e 41 /* Define to prevent redundant inclusion */
Anna Bridge 186:707f6e361f3e 42 #ifndef _MXC_LOCK_H_
Anna Bridge 186:707f6e361f3e 43 #define _MXC_LOCK_H_
Anna Bridge 186:707f6e361f3e 44
Anna Bridge 186:707f6e361f3e 45 /* **** Includes **** */
Anna Bridge 186:707f6e361f3e 46 #include "mxc_config.h"
Anna Bridge 186:707f6e361f3e 47 #include "mxc_lock.h"
Anna Bridge 186:707f6e361f3e 48
Anna Bridge 186:707f6e361f3e 49 #ifdef __cplusplus
Anna Bridge 186:707f6e361f3e 50 extern "C" {
Anna Bridge 186:707f6e361f3e 51 #endif
Anna Bridge 186:707f6e361f3e 52
Anna Bridge 186:707f6e361f3e 53 /* ************************************************************************** */
Anna Bridge 186:707f6e361f3e 54 int mxc_get_lock(uint32_t *lock, uint32_t value)
Anna Bridge 186:707f6e361f3e 55 {
Anna Bridge 186:707f6e361f3e 56 do {
Anna Bridge 186:707f6e361f3e 57
Anna Bridge 186:707f6e361f3e 58 // Return if the lock is taken by a different thread
Anna Bridge 186:707f6e361f3e 59 if(__LDREXW((volatile unsigned long *)lock) != 0) {
Anna Bridge 186:707f6e361f3e 60 return E_BUSY;
Anna Bridge 186:707f6e361f3e 61 }
Anna Bridge 186:707f6e361f3e 62
Anna Bridge 186:707f6e361f3e 63 // Attempt to take the lock
Anna Bridge 186:707f6e361f3e 64 } while(__STREXW(value, (volatile unsigned long *)lock) != 0);
Anna Bridge 186:707f6e361f3e 65
Anna Bridge 186:707f6e361f3e 66 // Do not start any other memory access until memory barrier is complete
Anna Bridge 186:707f6e361f3e 67 __DMB();
Anna Bridge 186:707f6e361f3e 68
Anna Bridge 186:707f6e361f3e 69 return E_NO_ERROR;
Anna Bridge 186:707f6e361f3e 70 }
Anna Bridge 186:707f6e361f3e 71
Anna Bridge 186:707f6e361f3e 72 /* ************************************************************************** */
Anna Bridge 186:707f6e361f3e 73 void mxc_free_lock(uint32_t *lock)
Anna Bridge 186:707f6e361f3e 74 {
Anna Bridge 186:707f6e361f3e 75 // Ensure memory operations complete before releasing lock
Anna Bridge 186:707f6e361f3e 76 __DMB();
Anna Bridge 186:707f6e361f3e 77 *lock = 0;
Anna Bridge 186:707f6e361f3e 78 }
Anna Bridge 186:707f6e361f3e 79
Anna Bridge 186:707f6e361f3e 80 #ifdef __cplusplus
Anna Bridge 186:707f6e361f3e 81 }
Anna Bridge 186:707f6e361f3e 82 #endif
Anna Bridge 186:707f6e361f3e 83 #endif /* _MXC_LOCK_H_ */