xref: /illumos-gate/usr/src/test/bhyve-tests/tests/kdev/payload_vpmtmr_freq.c (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
1 /*
2  * This file and its contents are supplied under the terms of the
3  * Common Development and Distribution License ("CDDL"), version 1.0.
4  * You may only use this file in accordance with the terms of version
5  * 1.0 of the CDDL.
6  *
7  * A full copy of the text of the CDDL should have accompanied this
8  * source.  A copy of the CDDL is also available via the Internet at
9  * http://www.illumos.org/license/CDDL.
10  */
11 
12 /*
13  * Copyright 2022 Oxide Computer Company
14  */
15 
16 #include "payload_common.h"
17 #include "payload_utils.h"
18 #include "test_defs.h"
19 
20 void
21 start(void)
22 {
23 	/* loop for as long as the host wants */
24 	for (;;) {
25 		uint32_t start, end;
26 
27 		start = inl(IOP_PMTMR);
28 		outl(IOP_TEST_VALUE, start);
29 
30 		do {
31 			end = inl(IOP_PMTMR);
32 			/* wait for enough ticks to pass */
33 		} while (end < (start + PMTMR_TARGET_TICKS));
34 		outl(IOP_TEST_VALUE, end);
35 	}
36 }
37