/*
* Timer Library (TLIB)
*
* The Library rely on timer drivers, the timer presented by the
* timer driver must look like a down-counter timer, which generates
* interrupt (if configured) when underflown.
*
* If Timer hardware is an up-counter the Timer driver must recalculate
* into values that would match as if it was a down-counter.
*
* COPYRIGHT (c) 2011.
* Cobham Gaisler AB.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*/
struct tlib_dev;
typedef void (*tlib_isr_t)(void *data);
struct tlib_drv {
/*** Functions ***/
void (*reset)(struct tlib_dev *hand);
void (*get_freq)(
struct tlib_dev *hand,
unsigned int *basefreq,
unsigned int *tickrate);
int (*set_freq)(struct tlib_dev *hand, unsigned int tickrate);
void (*irq_reg)(struct tlib_dev *hand, tlib_isr_t func, void *data);
void (*irq_unreg)(struct tlib_dev *hand, tlib_isr_t func,void *data);
void (*start)(struct tlib_dev *hand, int once);
void (*stop)(struct tlib_dev *hand);
void (*restart)(struct tlib_dev *hand);
void (*get_counter)(struct tlib_dev *hand, unsigned int *counter);
int (*custom)(struct tlib_dev *hand, int cmd, void *arg);
int (*int_pend)(struct tlib_dev *hand, int ack);
};
struct tlib_dev {
struct tlib_dev *next;
char status; /* 0=closed, 1=open, 2=timer started */
char index; /* Timer Index */
tlib_isr_t isr_func;
void *isr_data;
struct tlib_drv *drv;
};
#ifdef RTEMS_DRVMGR_STARTUP
/* Clock Driver Timer register function. Only used when the TLIB-Clock
* driver is used. A specific Timer is registered as the System Clock
* timer.
*/
extern void Clock_timer_register(int timer_number);
#endif
/* Register Timer. Called by Timer Drivers in order to register
* a Timer to the Timer Library. The registration order determines
* the Timer Number used in tlib_open() to identify a specific
* Timer.
*/
extern int tlib_dev_reg(struct tlib_dev *newdev);
/* Allocate a Timer.
*
* A Timer handle is returned identifying the timer in later calls.
*/
extern void *tlib_open(int timer_no);
/* Close Timer */
extern void tlib_close(void *hand);
/* Returns Number of Timers currently registered to Timer Library */
extern int tlib_ntimer(void);
static inline void tlib_reset(void *hand)
{
struct tlib_dev *dev = hand;
dev->drv->reset(dev);
}
/* Get Frequencies:
* - Base Frequency (unchangable base freq rate of timer, prescaler, clkinput)
* - Current Tick Rate [in multiples of Base Frequency]
*/
static inline void tlib_get_freq(
void *hand,
unsigned int *basefreq,
unsigned int *tickrate)
{
struct tlib_dev *dev = hand;
dev->drv->get_freq(dev, basefreq, tickrate);
}
/* Set current Tick Rate in number of "Base-Frequency ticks" */
static inline int tlib_set_freq(void *hand, unsigned int tickrate)
{
struct tlib_dev *dev = hand;
return dev->drv->set_freq(dev, tickrate);
}
/* Register ISR at Timer ISR */
static inline void tlib_irq_unregister(void *hand)
{
struct tlib_dev *dev = hand;
if ( dev->isr_func ) {
dev->drv->irq_unreg(dev, dev->isr_func, dev->isr_data);
dev->isr_func = NULL;
}
}
/* Register ISR at Timer ISR */
static inline void tlib_irq_register(void *hand, tlib_isr_t func, void *data)
{
struct tlib_dev *dev = hand;
/* Unregister previous ISR if installed */
tlib_irq_unregister(hand);
dev->isr_func = func;
dev->isr_data = data;
dev->drv->irq_reg(dev, func, data);
}
/* Start Timer, ISRs will be generated if enabled.
*
* once determines if timer should restart (=0) on underflow automatically,
* or stop when underflow is reached (=1).
*/
static inline void tlib_start(void *hand, int once)
{
struct tlib_dev *dev = hand;
dev->drv->start(dev, once);
}
/* Stop Timer, no more ISRs will be generated */
static inline void tlib_stop(void *hand)
{
struct tlib_dev *dev = hand;
dev->drv->stop(dev);
}
/* Restart/Reload Timer, may be usefull if a Watchdog Timer */
static inline void tlib_restart(void *hand)
{
struct tlib_dev *dev = hand;
dev->drv->restart(dev);
}
/* Get current counter value (since last tick) */
static inline void tlib_get_counter(void *hand, unsigned int *counter)
{
struct tlib_dev *dev = hand;
dev->drv->get_counter(dev, counter);
}
/* Do a custom operation */
static inline void tlib_custom(void *hand, int cmd, void *arg)
{
struct tlib_dev *dev = hand;
dev->drv->custom(dev, cmd, arg);
}
static inline int tlib_interrupt_pending(void *hand, int ack)
{
struct tlib_dev *dev = hand;
return dev->drv->int_pend(dev, ack);
}
