xref: /freebsd/sys/amd64/include/csan.h (revision 9768746b)
1 /*	$NetBSD: csan.h,v 1.2 2019/11/06 06:57:22 maxv Exp $	*/
2 
3 /*
4  * Copyright (c) 2019 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Maxime Villard.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  *
31  * $FreeBSD$
32  */
33 
34 #include <sys/timetc.h>
35 
36 #include <machine/clock.h>
37 #include <machine/cpufunc.h>
38 #include <machine/stack.h>
39 #include <machine/vmparam.h>
40 
41 static inline bool
42 kcsan_md_unsupported(vm_offset_t addr)
43 {
44 	return false;
45 }
46 
47 static inline bool
48 kcsan_md_is_avail(void)
49 {
50 	return true;
51 }
52 
53 static inline void
54 kcsan_md_disable_intrs(uint64_t *state)
55 {
56 
57 	*state = intr_disable();
58 }
59 
60 static inline void
61 kcsan_md_enable_intrs(uint64_t *state)
62 {
63 
64 	intr_restore(*state);
65 }
66 
67 static inline void
68 kcsan_md_delay(uint64_t us)
69 {
70 	/*
71 	 * Only call DELAY if not using the early delay code. The i8254
72 	 * early delay function may cause us to recurse on a spin lock
73 	 * leading to a panic.
74 	 */
75 	if ((tsc_is_invariant && tsc_freq != 0) ||
76 	    timecounter->tc_quality > 0)
77 		DELAY(us);
78 }
79 
80 static void
81 kcsan_md_unwind(void)
82 {
83 }
84