1 /*
2  * Copyright 2020 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  */
22 #include <nvif/timer.h>
23 #include <nvif/device.h>
24 
25 s64
nvif_timer_wait_test(struct nvif_timer_wait * wait)26 nvif_timer_wait_test(struct nvif_timer_wait *wait)
27 {
28 	u64 time = nvif_device_time(wait->device);
29 
30 	if (wait->reads == 0) {
31 		wait->time0 = time;
32 		wait->time1 = time;
33 	}
34 
35 	if (wait->time1 == time) {
36 		if (WARN_ON(wait->reads++ == 16))
37 			return -ETIMEDOUT;
38 	} else {
39 		wait->time1 = time;
40 		wait->reads = 1;
41 	}
42 
43 	if (wait->time1 - wait->time0 > wait->limit)
44 		return -ETIMEDOUT;
45 
46 	return wait->time1 - wait->time0;
47 }
48 
49 void
nvif_timer_wait_init(struct nvif_device * device,u64 nsec,struct nvif_timer_wait * wait)50 nvif_timer_wait_init(struct nvif_device *device, u64 nsec,
51 		     struct nvif_timer_wait *wait)
52 {
53 	wait->device = device;
54 	wait->limit = nsec;
55 	wait->reads = 0;
56 }
57