bios_timer.h

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#ifndef _GPXE_BIOS_TIMER_H
#define _GPXE_BIOS_TIMER_H

/** @file
 *
 * BIOS timer
 *
 */

FILE_LICENCE ( GPL2_OR_LATER );

#ifdef TIMER_PCBIOS
#define TIMER_PREFIX_pcbios
#else
#define TIMER_PREFIX_pcbios __pcbios_
#endif

#include <gpxe/timer2.h>

/**
 * Delay for a fixed number of microseconds
 *
 * @v usecs             Number of microseconds for which to delay
 */
static inline __always_inline void
TIMER_INLINE ( pcbios, udelay ) ( unsigned long usecs ) {
        /* BIOS timer is not high-resolution enough for udelay(), so
         * we use timer2
         */
        timer2_udelay ( usecs );
}

/**
 * Get number of ticks per second
 *
 * @ret ticks_per_sec   Number of ticks per second
 */
static inline __always_inline unsigned long
TIMER_INLINE ( pcbios, ticks_per_sec ) ( void ) {
        /* BIOS timer ticks over at 18.2 ticks per second */
        return 18;
}

#endif /* _GPXE_BIOS_TIMER_H */