rockbox/firmware/target/arm/as3525/timer-as3525.c
Rafaël Carré ed13fd6dca Sansa AMS: VIC_INT_ENABLE register is not a mask
When read it returns all enabled interrupt sources
When written it enables interrupt sources for each bit set
So just like VIC_INT_EN_CLEAR, we don't have to read the previous value
before writing to it (VIC_INT_EN_CLEAR is write-only anyway)

Thanks to Fred Bauer for spotting

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@23734 a1c6a512-1295-4272-9138-f99709370657
2009-11-24 12:05:53 +00:00

68 lines
2 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2008 Rafaël Carré
*
* 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 "as3525.h"
#include "timer.h"
#include "stdlib.h"
void INT_TIMER1(void)
{
if (pfn_timer != NULL)
pfn_timer();
TIMER1_INTCLR = 0; /* clear interrupt */
}
bool timer_set(long cycles, bool start)
{
if (start)
{
if (pfn_unregister != NULL)
{
pfn_unregister();
pfn_unregister = NULL;
}
}
TIMER1_LOAD = TIMER1_BGLOAD = cycles;
/* /!\ bit 4 (reserved) must not be modified
* periodic mode, interrupt enabled, no prescale, 32 bits counter */
TIMER1_CONTROL = (TIMER1_CONTROL & (1<<4)) |
TIMER_ENABLE |
TIMER_PERIODIC |
TIMER_INT_ENABLE |
TIMER_32_BIT;
return true;
}
bool timer_start(void)
{
CGU_PERI |= CGU_TIMER1_CLOCK_ENABLE; /* enable peripheral */
VIC_INT_ENABLE = INTERRUPT_TIMER1;
return true;
}
void timer_stop(void)
{
TIMER1_CONTROL &= 0x10; /* disable timer 1 (don't modify bit 4) */
VIC_INT_EN_CLEAR = INTERRUPT_TIMER1; /* disable interrupt */
CGU_PERI &= ~CGU_TIMER1_CLOCK_ENABLE; /* disable peripheral */
}