1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright 2020 Mellanox Technologies, Ltd
3 */
4
5 #include <inttypes.h>
6
7 #include <rte_windows.h>
8 #include <rte_common.h>
9 #include <rte_cycles.h>
10 #include <rte_eal.h>
11 #include <rte_errno.h>
12 #include "eal_private.h"
13
14 #define US_PER_SEC 1E6
15 #define CYC_PER_10MHZ 1E7
16
17 void
rte_delay_us_sleep(unsigned int us)18 rte_delay_us_sleep(unsigned int us)
19 {
20 HANDLE timer;
21 LARGE_INTEGER due_time;
22
23 /* create waitable timer */
24 timer = CreateWaitableTimer(NULL, TRUE, NULL);
25 if (!timer) {
26 RTE_LOG_WIN32_ERR("CreateWaitableTimer()");
27 rte_errno = ENOMEM;
28 return;
29 }
30
31 /*
32 * due_time's uom is 100 ns, multiply by 10 to convert to microseconds
33 * set us microseconds time for timer
34 */
35 due_time.QuadPart = -((int64_t)us * 10);
36 if (!SetWaitableTimer(timer, &due_time, 0, NULL, NULL, FALSE)) {
37 RTE_LOG_WIN32_ERR("SetWaitableTimer()");
38 rte_errno = EINVAL;
39 goto end;
40 }
41 /* start wait for timer for us microseconds */
42 if (WaitForSingleObject(timer, INFINITE) == WAIT_FAILED) {
43 RTE_LOG_WIN32_ERR("WaitForSingleObject()");
44 rte_errno = EINVAL;
45 }
46
47 end:
48 CloseHandle(timer);
49 }
50
51 uint64_t
get_tsc_freq(void)52 get_tsc_freq(void)
53 {
54 LARGE_INTEGER t_start, t_end, elapsed_us;
55 LARGE_INTEGER frequency;
56 uint64_t tsc_hz;
57 uint64_t end, start;
58
59 QueryPerformanceFrequency(&frequency);
60
61 QueryPerformanceCounter(&t_start);
62 start = rte_get_tsc_cycles();
63
64 rte_delay_us_sleep(US_PER_SEC / 10); /* 1/10 second */
65
66 if (rte_errno != 0)
67 return 0;
68
69 QueryPerformanceCounter(&t_end);
70 end = rte_get_tsc_cycles();
71
72 elapsed_us.QuadPart = t_end.QuadPart - t_start.QuadPart;
73
74 /*
75 * To guard against loss-of-precision, convert to microseconds
76 * *before* dividing by ticks-per-second.
77 */
78 elapsed_us.QuadPart *= US_PER_SEC;
79 elapsed_us.QuadPart /= frequency.QuadPart;
80
81 double secs = ((double)elapsed_us.QuadPart)/US_PER_SEC;
82 tsc_hz = (uint64_t)((end - start)/secs);
83
84 /* Round up to 10Mhz. 1E7 ~ 10Mhz */
85 return RTE_ALIGN_MUL_NEAR(tsc_hz, CYC_PER_10MHZ);
86 }
87
88
89 int
rte_eal_timer_init(void)90 rte_eal_timer_init(void)
91 {
92 set_tsc_freq();
93 return 0;
94 }
95