view src/cs/drivers/drv_core/timer/timer.c @ 220:0ed36de51973

ABB semaphore protection overhaul The ABB semaphone protection logic that came with TCS211 from TI was broken in several ways: * Some semaphore-protected functions were called from Application_Initialize() context. NU_Obtain_Semaphore() called with NU_SUSPEND fails with NU_INVALID_SUSPEND in this context, but the return value wasn't checked, and NU_Release_Semaphore() would be called unconditionally at the end. The latter call would increment the semaphore count past 1, making the semaphore no longer binary and thus no longer effective for resource protection. The fix is to check the return value from NU_Obtain_Semaphore() and skip the NU_Release_Semaphore() call if the semaphore wasn't properly obtained. * Some SPI hardware manipulation was being done before entering the semaphore- protected critical section. The fix is to reorder the code: first obtain the semaphore, then do everything else. * In the corner case of L1/DSP recovery, l1_abb_power_on() would call some non-semaphore-protected ABB & SPI init functions. The fix is to skip those calls in the case of recovery. * A few additional corner cases existed, all of which are fixed by making ABB semaphore protection 100% consistent for all ABB functions and code paths. There is still one remaining problem of priority inversion: suppose a low- priority task calls an ABB function, and some medium-priority task just happens to preempt right in the middle of that semaphore-protected ABB operation. Then the high-priority SPI task is locked out for a non-deterministic time until that medium-priority task finishes its work and goes back to sleep. This priority inversion problem remains outstanding for now.
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 26 Apr 2021 20:55:25 +0000
parents 4e78acac3d88
children
line wrap: on
line source

/*******************************************************************************
            TEXAS INSTRUMENTS INCORPORATED PROPRIETARY INFORMATION           
                                                                             
   Property of Texas Instruments -- For  Unrestricted  Internal  Use  Only 
   Unauthorized reproduction and/or distribution is strictly prohibited.  This 
   product  is  protected  under  copyright  law  and  trade  secret law as an 
   unpublished work.  Created 1987, (C) Copyright 1997 Texas Instruments.  All 
   rights reserved.                                                            
                  
                                                           
   Filename         : timer.c

   Description      : timer.c

   Project          : drivers

   Author           : pmonteil@tif.ti.com  Patrice Monteil.

   Version number   : 1.3

   Date and time    : 07/23/98 16:25:32
   Previous delta   : 07/23/98 16:25:32

   SCCS file        : /db/gsm_asp/db_ht96/dsp_0/gsw/rel_0/mcu_l1/release1.5/mod/emu/EMU_MCMP/eva3_drivers/source/SCCS/s.timer.c

   Sccs Id  (SID)       : '@(#) timer.c 1.3 07/23/98 16:25:32 '

 
*****************************************************************************/

#include "l1sw.cfg"

#if (OP_L1_STANDALONE == 0)
  #include "main/sys_types.h"
#else
  #include "sys_types.h"
#endif
#include "memif/mem.h"
#include "inth/iq.h"
#include "timer.h"


/*--------------------------------------------------------------
 *  TIMER_Read()
 *--------------------------------------------------------------
 * Parameters :	num of the register to be read
 * Return     :value of the timer register read
 * Functionality :  read one of the TIMER register
 *--------------------------------------------------------------*/
SYS_UWORD16 TIMER_Read (unsigned short regNum)
{
   volatile SYS_UWORD16 timerReg;

   switch (regNum) {
   case 0:
      timerReg = (( * (SYS_UWORD16 *) TIMER_CNTL_REG) & TIMER_CNTL_MASK);
      break;
   case 1:
      timerReg = ( * (SYS_UWORD16 *) TIMER_READ_REG);
      break;
   case 2:
      timerReg = (( * (SYS_UWORD16 *) TIMER_MODE_REG) & TIMER_MODE_MASK);
      break;
   default:
       break;
   }
   return(timerReg);
}
/*--------------------------------------------------------------
 *  TM_ResetTimer()
 *--------------------------------------------------------------
 * Parameters : timer number (1 or 2) 
 *              timer value, reload yes or not, scale
 * Return     : none
 * Functionality : Give the timewr state
 *--------------------------------------------------------------*/
void  TM_ResetTimer (SYS_UWORD16 timerNum,  SYS_UWORD16 countValue, 
                     SYS_UWORD16 autoReload, SYS_UWORD16 clockScale)
{
     volatile SYS_UWORD16 *cntl;
    
    if (timerNum == 1) 
    {
        cntl = (volatile SYS_UWORD16 *) TIMER1_CNTL; 

        *cntl &= ~(START_STOP | PTV);        /* stop and reset values */

        (autoReload) ? (*cntl |= AR) : (*cntl &= ~AR);

        *cntl |= (clockScale << 2 );


        * (SYS_UWORD16 *) TIMER1_LOAD_TIM = countValue;  /*load the value */

        *cntl |= START_STOP;    
    }
    else 
    {
        cntl = (volatile SYS_UWORD16 *) TIMER2_CNTL; 

        *cntl &= ~(START_STOP | PTV);        /* stop and reset values */

        (autoReload) ? (*cntl |= AR) : (*cntl &= ~AR);

        *cntl |= (clockScale << 2 );
         

        * (SYS_UWORD16 *) TIMER2_LOAD_TIM = countValue;  /*load the value */

        *cntl |= START_STOP;    
    }
}

/*
 *  TM_StopTimer
 *
 * Parameters : timer number (1 or 2)
 */
void   TM_StopTimer (int timerNum)
{

    volatile SYS_UWORD16 *cntl;
    
    if (timerNum == 1) 
    {
        cntl = (volatile SYS_UWORD16 *) TIMER1_CNTL;
    }
    else
    {
        cntl = (volatile SYS_UWORD16 *) TIMER2_CNTL;
    }
    *cntl &= ~START_STOP;

}   

/*
 * TM_ReadTimer
 *
 * Returns current timer value
 *
 * Parameters : timer number (1 or 2)
 *
 */
SYS_UWORD16 TM_ReadTimer (int timerNum)
{
    if (timerNum == 1) 
    {
        return (* (SYS_UWORD16 *) TIMER1_READ_TIM);
    }
    else
    {
        return (* (SYS_UWORD16 *) TIMER2_READ_TIM);
    }
}   


/*
 * TM_StartTimer
 *
 * Parameters : timer number (1 or 2)
 *
 */
void TM_StartTimer (int timerNum)
{
    volatile SYS_UWORD16 *cntl;
    
    if (timerNum == 1) 
    {
        cntl = (volatile SYS_UWORD16 *) TIMER1_CNTL;
    }
    else
    {
        cntl = (volatile SYS_UWORD16 *) TIMER2_CNTL;
    }
    *cntl |= START_STOP;
}   

void TM_DisableWatchdog (void)
{
   /* volatile variable needed due C to optimization */
   volatile SYS_UWORD16 *reg = (volatile SYS_UWORD16 *) TIMER_MODE_REG;

   *reg = 0xf5;                
   *reg = 0xa0;
}


 /*
 * TM_EnableWatchdog
 * 
 */
void TM_EnableWatchdog(void)
{
    * ((volatile SYS_UWORD16 *) TIMER_MODE_REG) = TIMER_WDOG;
}

/*
 * TM_ResetWatchdog
 * 
 * Parameter : Tick count 
 * Use a different value each time, otherwise watchdog bites 
 */
void TM_ResetWatchdog(SYS_UWORD16 count)
{
  * ((volatile SYS_UWORD16 *) TIMER_LOAD_REG) = count;
}

/*
* TM_EnableTimer (int TimerNum)
* 
* Parameter : TimerNum : timer to enable (timer1 or timer2)
*
*/
void TM_EnableTimer (int TimerNum)
{
     volatile SYS_UWORD16 *cntl;
    
    if (TimerNum == 1) 
    {
        cntl = (volatile SYS_UWORD16 *) TIMER1_CNTL;
    }
    else
    {
        cntl = (volatile SYS_UWORD16 *) TIMER2_CNTL;
    }
    *cntl |= TIMER_CLK_EN;

}

/*
* TM_DisableTimer (int TimerNum)
* 
* Parameter : TimerNum : timer to enable (timer1 or timer2)
*
*/
void TM_DisableTimer (int TimerNum)
{
     volatile SYS_UWORD16 *cntl;
    
    if (TimerNum == 1) 
    {
        cntl = (volatile SYS_UWORD16 *) TIMER1_CNTL;
    }
    else
    {
        cntl = (volatile SYS_UWORD16 *) TIMER2_CNTL;
    }
    *cntl &= ~TIMER_CLK_EN;
}

/*--------------------------------------------------------------
 *  TIMER_ReadValue()
 *--------------------------------------------------------------
 * Parameters : none
 * Return     :	none
 * Functionality :  Read timer value
 *--------------------------------------------------------------*/

unsigned short TIMER_ReadValue (void)
{
  return(* (SYS_UWORD16 *) TIMER_READ_REG);
 
}

/*--------------------------------------------------------------
 *  TIMER_WriteValue()
 *--------------------------------------------------------------
 * Parameters : none
 * Return     :	none
 * Functionality :  Write timer value
 *--------------------------------------------------------------*/

void TIMER_WriteValue (SYS_UWORD16 value)
{
  * (SYS_UWORD16 *) TIMER_LOAD_REG = value;	/*load the value */
 
}