Vhex-kernel/src/kernel/drivers/timers/install.c

55 lines
1.3 KiB
C

#include <kernel/drivers/timer.h>
#include <kernel/hardware/tmu.h>
#include <kernel/util/atomic.h>
/*
** int timer_instal(void*, void*, tmode_t)
**
** @info
** This function will try to setup an hardware timer.
*/
int timer_install(void *callback, void *arg, uint32_t ticks, tmode_t mode)
{
extern struct timer_cache_s timercache[TIMER_NUMBER];
int timer_ID;
// Do atomic operation because of
// sheared timer cache and I/O access.
atomic_start();
// Find free timer.
timer_ID = -1;
while (++timer_ID < TIMER_NUMBER &&
timercache[timer_ID].status != TIMER_UNUSED);
if (timer_ID >= TIMER_NUMBER)
{
atomic_stop();
return (-1);
}
// Initialise internal timer data.
timercache[timer_ID].callback = callback;
timercache[timer_ID].status = mode;
timercache[timer_ID].arg = arg;
// Initialise hardware module.
SH7305_TMU.TSTR.BYTE &= ~(1 << timer_ID); // Stop timer.
// Setup Timer
SH7305_TMU.TIMER[timer_ID].TCOR = ticks;
SH7305_TMU.TIMER[timer_ID].TCNT = ticks;
// Configure timer
SH7305_TMU.TIMER[timer_ID].TCR.UNF = 0; // Clear interrupt flag.
SH7305_TMU.TIMER[timer_ID].TCR.UNIE = 1; // Enable interrupt.
// Start timer if needed.
if (mode == TIMER_START)
SH7305_TMU.TSTR.BYTE |= 1 << timer_ID;
// End of atomic operations.
// and return the timer ID.
atomic_stop();
return (timer_ID);
}