1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2018, Linaro Limited 4 * Copyright (C) 2017, Fuzhou Rockchip Electronics Co., Ltd. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright notice, 11 * this list of conditions and the following disclaimer. 12 * 13 * 2. Redistributions in binary form must reproduce the above copyright notice, 14 * this list of conditions and the following disclaimer in the documentation 15 * and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 18 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 21 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 * POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include <kernel/boot.h> 31 #include <kernel/delay.h> 32 #include <kernel/misc.h> 33 34 #ifdef CFG_CORE_HAS_GENERIC_TIMER 35 int timeout_elapsed_us(uint64_t expire) 36 { 37 int64_t diff = delay_cnt_read() - expire; 38 39 if (MUL_OVERFLOW(diff, 1000000, &diff) || 40 diff < INT_MIN || diff > INT_MAX) { 41 if (timeout_elapsed(expire)) 42 return INT_MAX; 43 else 44 return INT_MIN; 45 } 46 47 return diff / delay_cnt_freq(); 48 } 49 50 void udelay(uint32_t us) 51 { 52 uint64_t target = timeout_init_us(us); 53 54 while (!timeout_elapsed(target)) 55 ; 56 } 57 #else 58 59 void udelay(uint32_t us) 60 { 61 uint64_t cycles = 0; 62 uint32_t cycles_to_wait = 0; 63 64 cycles = (uint64_t)us * ((uint64_t)plat_get_freq() / 1000000ULL); 65 66 while (cycles) { 67 cycles_to_wait = MIN(cycles, UINT32_MAX); 68 wait_cycles(cycles_to_wait); 69 cycles -= cycles_to_wait; 70 } 71 } 72 #endif 73 74 void mdelay(uint32_t ms) 75 { 76 udelay(1000 * ms); 77 } 78