1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * Simple xorshift PRNG 4 * see http://www.jstatsoft.org/v08/i14/paper 5 * 6 * Copyright (c) 2012 Michael Walle 7 * Michael Walle <michael@walle.cc> 8 */ 9 10#include <common.h> 11#include <rand.h> 12 13static unsigned int y = 1U; 14 15unsigned int rand_r(unsigned int *seedp) 16{ 17 *seedp ^= (*seedp << 13); 18 *seedp ^= (*seedp >> 17); 19 *seedp ^= (*seedp << 5); 20 21 return *seedp; 22} 23 24unsigned int rand(void) 25{ 26 return rand_r(&y); 27} 28 29void srand(unsigned int seed) 30{ 31 y = seed; 32} 33