static unsigned long
div64_32(unsigned long v1, unsigned long v2, unsigned long v3)
{
unsigned long r0;
do_div64_32(r0, v1, v2, v3);
return r0;
}
/*
* This is copied from dec/time.c:do_ioasic_gettimeoffset() by Mercij.
*/
unsigned long calibrate_div32_gettimeoffset(void)
{
u32 count;
unsigned long res, tmp;
unsigned long quotient;
tmp = jiffies;
quotient = cached_quotient;
if (last_jiffies != tmp) {
last_jiffies = tmp;
if (last_jiffies != 0) {
unsigned long r0;
do_div64_32(r0, timerhi, timerlo, tmp);
do_div64_32(quotient, USECS_PER_JIFFY,
USECS_PER_JIFFY_FRAC, r0);
cached_quotient = quotient;
}
}
/* Get last timer tick in absolute kernel time */
count = read_32bit_cp0_register(CP0_COUNT);
/* .. relative to previous jiffy (32 bits is enough) */
count -= timerlo;
__asm__("multu %2,%3"
: "=l" (tmp), "=h" (res)
: "r" (count), "r" (quotient));
/*
* Due to possible jiffies inconsistencies, we need to check
* the result so that we'll get a timer that is monotonic.
*/
if (res >= USECS_PER_JIFFY)
res = USECS_PER_JIFFY - 1;
return res;
}
