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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;
    	}
    }