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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2011 by Amaury Pouly
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "kernel.h"
#include "timrot-imx233.h"
#include "clkctrl-imx233.h"
#include "kernel-imx233.h"
#include "regs/timrot.h"
static void tick_timer(void)
{
/* Run through the list of tick tasks */
call_tick_tasks();
}
void tick_start(unsigned int interval_in_ms)
{
/* use the 1-kHz XTAL clock source */
imx233_timrot_setup_simple(TIMER_TICK, true, interval_in_ms, TIMER_SRC_1KHZ, &tick_timer);
}
void arbiter_init(struct channel_arbiter_t *a, unsigned count)
{
mutex_init(&a->mutex);
semaphore_init(&a->sema, count, count);
a->free_bm = (1 << count) - 1;
a->count = count;
}
// doesn't check in use !
void arbiter_reserve(struct channel_arbiter_t *a, unsigned channel)
{
// assume semaphore has a free slot immediately
if(semaphore_wait(&a->sema, TIMEOUT_NOBLOCK) != OBJ_WAIT_SUCCEEDED)
panicf("arbiter_reserve failed on semaphore_wait !");
mutex_lock(&a->mutex);
a->free_bm &= ~(1 << channel);
mutex_unlock(&a->mutex);
}
int arbiter_acquire(struct channel_arbiter_t *a, int timeout)
{
int w = semaphore_wait(&a->sema, timeout);
if(w == OBJ_WAIT_TIMEDOUT)
return w;
mutex_lock(&a->mutex);
int chan = find_first_set_bit(a->free_bm);
if(chan >= a->count)
panicf("arbiter_acquire cannot find a free channel !");
a->free_bm &= ~(1 << chan);
mutex_unlock(&a->mutex);
return chan;
}
bool arbiter_acquired(struct channel_arbiter_t *a, int channel)
{
return !(a->free_bm & (1 << channel));
}
void arbiter_release(struct channel_arbiter_t *a, int channel)
{
mutex_lock(&a->mutex);
a->free_bm |= 1 << channel;
mutex_unlock(&a->mutex);
semaphore_release(&a->sema);
}
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