Rtos code cntains bug possible incompatability with I2C
Fork of mbed-rtos by
Diff: rtx/TARGET_CORTEX_A/rt_Mutex.c
- Revision:
- 49:77c8e4604045
- Parent:
- 48:e9a2c7cb57a4
- Child:
- 68:d3d0e710b443
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/rtx/TARGET_CORTEX_A/rt_Mutex.c Thu Nov 06 13:00:11 2014 +0000 @@ -0,0 +1,204 @@ +/*---------------------------------------------------------------------------- + * RL-ARM - RTX + *---------------------------------------------------------------------------- + * Name: RT_MUTEX.C + * Purpose: Implements mutex synchronization objects + * Rev.: V4.60 + *---------------------------------------------------------------------------- + * + * Copyright (c) 1999-2009 KEIL, 2009-2012 ARM Germany GmbH + * All rights reserved. + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * - 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. + * - Neither the name of ARM 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 COPYRIGHT HOLDERS AND 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. + *---------------------------------------------------------------------------*/ + +#include "rt_TypeDef.h" +#include "RTX_Config.h" +#include "rt_List.h" +#include "rt_Task.h" +#include "rt_Mutex.h" +#ifdef __CORTEX_A9 +#include "rt_HAL_CA.h" +#else +#include "rt_HAL_CM.h" +#endif + + +/*---------------------------------------------------------------------------- + * Functions + *---------------------------------------------------------------------------*/ + + +/*--------------------------- rt_mut_init -----------------------------------*/ + +void rt_mut_init (OS_ID mutex) { + /* Initialize a mutex object */ + P_MUCB p_MCB = mutex; + + p_MCB->cb_type = MUCB; + p_MCB->prio = 0; + p_MCB->level = 0; + p_MCB->p_lnk = NULL; + p_MCB->owner = NULL; +} + + +/*--------------------------- rt_mut_delete ---------------------------------*/ + +#ifdef __CMSIS_RTOS +OS_RESULT rt_mut_delete (OS_ID mutex) { + /* Delete a mutex object */ + P_MUCB p_MCB = mutex; + P_TCB p_TCB; + + __DMB(); + /* Restore owner task's priority. */ + if (p_MCB->level != 0) { + p_MCB->owner->prio = p_MCB->prio; + if (p_MCB->owner != os_tsk.run) { + rt_resort_prio (p_MCB->owner); + } + } + + while (p_MCB->p_lnk != NULL) { + /* A task is waiting for mutex. */ + p_TCB = rt_get_first ((P_XCB)p_MCB); + rt_ret_val(p_TCB, 0/*osOK*/); + rt_rmv_dly(p_TCB); + p_TCB->state = READY; + rt_put_prio (&os_rdy, p_TCB); + } + + if (os_rdy.p_lnk && (os_rdy.p_lnk->prio > os_tsk.run->prio)) { + /* preempt running task */ + rt_put_prio (&os_rdy, os_tsk.run); + os_tsk.run->state = READY; + rt_dispatch (NULL); + } + + p_MCB->cb_type = 0; + + return (OS_R_OK); +} +#endif + + +/*--------------------------- rt_mut_release --------------------------------*/ + +OS_RESULT rt_mut_release (OS_ID mutex) { + /* Release a mutex object */ + P_MUCB p_MCB = mutex; + P_TCB p_TCB; + + if (p_MCB->level == 0 || p_MCB->owner != os_tsk.run) { + /* Unbalanced mutex release or task is not the owner */ + return (OS_R_NOK); + } + __DMB(); + if (--p_MCB->level != 0) { + return (OS_R_OK); + } + /* Restore owner task's priority. */ + os_tsk.run->prio = p_MCB->prio; + if (p_MCB->p_lnk != NULL) { + /* A task is waiting for mutex. */ + p_TCB = rt_get_first ((P_XCB)p_MCB); +#ifdef __CMSIS_RTOS + rt_ret_val(p_TCB, 0/*osOK*/); +#else + rt_ret_val(p_TCB, OS_R_MUT); +#endif + rt_rmv_dly (p_TCB); + /* A waiting task becomes the owner of this mutex. */ + p_MCB->level = 1; + p_MCB->owner = p_TCB; + p_MCB->prio = p_TCB->prio; + /* Priority inversion, check which task continues. */ + if (os_tsk.run->prio >= rt_rdy_prio()) { + rt_dispatch (p_TCB); + } + else { + /* Ready task has higher priority than running task. */ + rt_put_prio (&os_rdy, os_tsk.run); + rt_put_prio (&os_rdy, p_TCB); + os_tsk.run->state = READY; + p_TCB->state = READY; + rt_dispatch (NULL); + } + } + else { + /* Check if own priority raised by priority inversion. */ + if (rt_rdy_prio() > os_tsk.run->prio) { + rt_put_prio (&os_rdy, os_tsk.run); + os_tsk.run->state = READY; + rt_dispatch (NULL); + } + } + return (OS_R_OK); +} + + +/*--------------------------- rt_mut_wait -----------------------------------*/ + +OS_RESULT rt_mut_wait (OS_ID mutex, U16 timeout) { + /* Wait for a mutex, continue when mutex is free. */ + P_MUCB p_MCB = mutex; + + if (p_MCB->level == 0) { + p_MCB->owner = os_tsk.run; + p_MCB->prio = os_tsk.run->prio; + goto inc; + } + if (p_MCB->owner == os_tsk.run) { + /* OK, running task is the owner of this mutex. */ +inc:p_MCB->level++; + __DMB(); + return (OS_R_OK); + } + /* Mutex owned by another task, wait until released. */ + if (timeout == 0) { + return (OS_R_TMO); + } + /* Raise the owner task priority if lower than current priority. */ + /* This priority inversion is called priority inheritance. */ + if (p_MCB->prio < os_tsk.run->prio) { + p_MCB->owner->prio = os_tsk.run->prio; + rt_resort_prio (p_MCB->owner); + } + if (p_MCB->p_lnk != NULL) { + rt_put_prio ((P_XCB)p_MCB, os_tsk.run); + } + else { + p_MCB->p_lnk = os_tsk.run; + os_tsk.run->p_lnk = NULL; + os_tsk.run->p_rlnk = (P_TCB)p_MCB; + } + rt_block(timeout, WAIT_MUT); + return (OS_R_TMO); +} + + +/*---------------------------------------------------------------------------- + * end of file + *---------------------------------------------------------------------------*/ +