mirror of
https://github.com/fail0verflow/hbc.git
synced 2024-11-16 22:59:23 +01:00
28 lines
390 B
C
28 lines
390 B
C
#include "common.h"
|
|
|
|
// Timebase frequency is bus frequency / 4. Ignore roundoff, this
|
|
// doesn't have to be very accurate.
|
|
#define TICKS_PER_USEC (243/4)
|
|
|
|
static u32 mftb(void)
|
|
{
|
|
u32 x;
|
|
|
|
asm volatile("mftb %0" : "=r"(x));
|
|
|
|
return x;
|
|
}
|
|
|
|
static void __delay(u32 ticks)
|
|
{
|
|
u32 start = mftb();
|
|
|
|
while (mftb() - start < ticks)
|
|
;
|
|
}
|
|
|
|
void udelay(u32 us)
|
|
{
|
|
__delay(TICKS_PER_USEC * us);
|
|
}
|