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
timeout_elapsed_us(uint64_t expire)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
udelay(uint32_t us)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
udelay(uint32_t us)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
mdelay(uint32_t ms)74 void mdelay(uint32_t ms)
75 {
76 udelay(1000 * ms);
77 }
78