xref: /freebsd/sys/amd64/include/csan.h (revision 02e9120893770924227138ba49df1edb3896112a)
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 
32 #include <sys/timetc.h>
33 
34 #include <machine/clock.h>
35 #include <machine/cpufunc.h>
36 #include <machine/stack.h>
37 #include <machine/vmparam.h>
38 
39 static inline bool
40 kcsan_md_unsupported(vm_offset_t addr)
41 {
42 	return false;
43 }
44 
45 static inline bool
46 kcsan_md_is_avail(void)
47 {
48 	return true;
49 }
50 
51 static inline void
52 kcsan_md_disable_intrs(uint64_t *state)
53 {
54 
55 	*state = intr_disable();
56 }
57 
58 static inline void
59 kcsan_md_enable_intrs(uint64_t *state)
60 {
61 
62 	intr_restore(*state);
63 }
64 
65 static inline void
66 kcsan_md_delay(uint64_t us)
67 {
68 	/*
69 	 * Only call DELAY if not using the early delay code. The i8254
70 	 * early delay function may cause us to recurse on a spin lock
71 	 * leading to a panic.
72 	 */
73 	if ((tsc_is_invariant && tsc_freq != 0) ||
74 	    timecounter->tc_quality > 0)
75 		DELAY(us);
76 }
77 
78 static void
79 kcsan_md_unwind(void)
80 {
81 }
82