u-boot/arch/arm/cpu/armv7/omap-common/utils.c

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/*
* Copyright 2011 Linaro Limited
* Aneesh V <aneesh@ti.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
static void do_cancel_out(u32 *num, u32 *den, u32 factor)
{
while (1) {
if (((*num)/factor*factor == (*num)) &&
((*den)/factor*factor == (*den))) {
(*num) /= factor;
(*den) /= factor;
} else
break;
}
}
/*
* Cancel out the denominator and numerator of a fraction
* to get smaller numerator and denominator.
*/
void cancel_out(u32 *num, u32 *den, u32 den_limit)
{
do_cancel_out(num, den, 2);
do_cancel_out(num, den, 3);
do_cancel_out(num, den, 5);
do_cancel_out(num, den, 7);
do_cancel_out(num, den, 11);
do_cancel_out(num, den, 13);
do_cancel_out(num, den, 17);
while ((*den) > den_limit) {
*num /= 2;
/*
* Round up the denominator so that the final fraction
* (num/den) is always <= the desired value
*/
*den = (*den + 1) / 2;
}
}