xref: /netbsd-src/sys/external/bsd/drm2/dist/include/drm/drm_util.h (revision c58db6da0a032dee0aaaa7fd27f9ee2294505f83)
1 /*	$NetBSD: drm_util.h,v 1.4 2021/12/19 10:32:47 riastradh Exp $	*/
2 
3 /*
4  * Internal Header for the Direct Rendering Manager
5  *
6  * Copyright 2018 Intel Corporation
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a
9  * copy of this software and associated documentation files (the "Software"),
10  * to deal in the Software without restriction, including without limitation
11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
12  * and/or sell copies of the Software, and to permit persons to whom the
13  * Software is furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice (including the next
16  * paragraph) shall be included in all copies or substantial portions of the
17  * Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
22  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
25  * OTHER DEALINGS IN THE SOFTWARE.
26  */
27 
28 #ifndef _DRM_UTIL_H_
29 #define _DRM_UTIL_H_
30 
31 /**
32  * DOC: drm utils
33  *
34  * Macros and inline functions that does not naturally belong in other places
35  */
36 
37 #include <linux/interrupt.h>
38 #include <linux/kgdb.h>
39 #include <linux/preempt.h>
40 #include <linux/smp.h>
41 
42 #ifdef __NetBSD__
43 #include <drm/drm_wait_netbsd.h>
44 #endif
45 
46 /*
47  * Use EXPORT_SYMBOL_FOR_TESTS_ONLY() for functions that shall
48  * only be visible for drmselftests.
49  */
50 #if defined(CONFIG_DRM_EXPORT_FOR_TESTS)
51 #define EXPORT_SYMBOL_FOR_TESTS_ONLY(x) EXPORT_SYMBOL(x)
52 #else
53 #define EXPORT_SYMBOL_FOR_TESTS_ONLY(x)
54 #endif
55 
56 /**
57  * for_each_if - helper for handling conditionals in various for_each macros
58  * @condition: The condition to check
59  *
60  * Typical use::
61  *
62  *	#define for_each_foo_bar(x, y) \'
63  *		list_for_each_entry(x, y->list, head) \'
64  *			for_each_if(x->something == SOMETHING)
65  *
66  * The for_each_if() macro makes the use of for_each_foo_bar() less error
67  * prone.
68  */
69 #define for_each_if(condition) if (!(condition)) {} else
70 
71 /**
72  * drm_can_sleep - returns true if currently okay to sleep
73  *
74  * This function shall not be used in new code.
75  * The check for running in atomic context may not work - see linux/preempt.h.
76  *
77  * FIXME: All users of drm_can_sleep should be removed (see todo.rst)
78  *
79  * Returns:
80  * False if kgdb is active, we are in atomic context or irqs are disabled.
81  */
drm_can_sleep(void)82 static inline bool drm_can_sleep(void)
83 {
84 #ifdef __NetBSD__
85 	return false;		/* XXX */
86 #else
87 	if (in_atomic() || in_dbg_master() || irqs_disabled())
88 		return false;
89 	return true;
90 #endif
91 }
92 
93 #endif
94