nouveau/nvif/timer.c

0001 /*
0002  * Copyright 2020 Red Hat Inc.
0003  *
0004  * Permission is hereby granted, free of charge, to any person obtaining a
0005  * copy of this software and associated documentation files (the "Software"),
0006  * to deal in the Software without restriction, including without limitation
0007  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
0008  * and/or sell copies of the Software, and to permit persons to whom the
0009  * Software is furnished to do so, subject to the following conditions:
0010  *
0011  * The above copyright notice and this permission notice shall be included in
0012  * all copies or substantial portions of the Software.
0013  *
0014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
0015  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
0016  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
0017  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
0018  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
0019  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
0020  * OTHER DEALINGS IN THE SOFTWARE.
0021  */
0022 #include <nvif/timer.h>
0023 #include <nvif/device.h>
0024
0025 s64
0026 nvif_timer_wait_test(struct nvif_timer_wait *wait)
0027 {
0028     u64 time = nvif_device_time(wait->device);
0029
0030     if (wait->reads == 0) {
0031         wait->time0 = time;
0032         wait->time1 = time;
0033     }
0034
0035     if (wait->time1 == time) {
0036         if (WARN_ON(wait->reads++ == 16))
0037             return -ETIMEDOUT;
0038     } else {
0039         wait->time1 = time;
0040         wait->reads = 1;
0041     }
0042
0043     if (wait->time1 - wait->time0 > wait->limit)
0044         return -ETIMEDOUT;
0045
0046     return wait->time1 - wait->time0;
0047 }
0048
0049 void
0050 nvif_timer_wait_init(struct nvif_device *device, u64 nsec,
0051              struct nvif_timer_wait *wait)
0052 {
0053     wait->device = device;
0054     wait->limit = nsec;
0055     wait->reads = 0;
0056 }