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/*

(C) Copyright IBM Corp. 2008

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 IBM 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 THE COPYRIGHT OWNER OR 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.

*/

/* SPU timer stop library service.  */

#include <spu_timer.h>

#include "spu_timer_internal.h"

/* Stop a timer.  Moves it from either the active or handled list to the

   stopped list. Returns 0 on sucess, timer was successfully stopped.

   Returns <0 - Failure:

    * SPU_TIMER_ERR_NOT_ACTIVE - timer was not active

    * SPU_TIMER_ERR_INVALID_ID - invalid timer id

    * SPU_TIMER_ERR_NOCLOCK    -  spu clock is not running  */

int

spu_timer_stop (int id)

{

  spu_timer_t *t, **pn;

  unsigned was_enabled;

  if (id < 0 || id >= SPU_TIMER_NTIMERS)

    return SPU_TIMER_ERR_INVALID_ID;

  if (__spu_clock_startcnt == 0)

    return SPU_TIMER_ERR_NOCLOCK;

  /* Free or stopped states.  */

  if (__spu_timers[id].state == SPU_TIMER_ACTIVE ||

      __spu_timers[id].state == SPU_TIMER_HANDLED)

    {

      was_enabled = spu_readch (SPU_RdMachStat) & 0x1;

      spu_idisable ();

      /* Timer is on either active list or handled list.  */

      t = (__spu_timers[id].state == SPU_TIMER_ACTIVE)

        ? __spu_timers_active : __spu_timers_handled;

      pn = (__spu_timers[id].state == SPU_TIMER_ACTIVE)

        ? &__spu_timers_active : &__spu_timers_handled;

      while (t && t->id != id)

        {

          pn = &t->next;

          t = t->next;

        }

#ifdef SPU_TIMER_DEBUG

      if (!t)

        ABORT (); /* Internal error.  */

#endif

      /* Fix timeout of next timer and decrementer if we were at the head of

         the active list.  */

      if (t->next)

        {

          t->next->tmout += t->tmout;

          if (__spu_timers_active == t)

            __reset_spu_decr (t->next->tmout);

        }

      else

        __reset_spu_decr (CLOCK_START_VALUE);

      *pn = t->next; /* Update this elements to pointer.  */

      t->next = __spu_timers_stopped;

      __spu_timers_stopped = t;

      __spu_timers[id].state = SPU_TIMER_STOPPED;

      if (__likely (was_enabled))

        spu_ienable ();

      return 0;

    }

  return SPU_TIMER_ERR_NOT_ACTIVE;

}