xref: /linux/drivers/gpu/drm/i915/i915_utils.h (revision 815e260a18a3af4dab59025ee99a7156c0e8b5e0)
1 /*
2  * Copyright © 2016 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  */
24 
25 #ifndef __I915_UTILS_H
26 #define __I915_UTILS_H
27 
28 #include <linux/overflow.h>
29 #include <linux/sched.h>
30 #include <linux/string_helpers.h>
31 #include <linux/types.h>
32 #include <linux/workqueue.h>
33 #include <linux/sched/clock.h>
34 
35 #ifdef CONFIG_X86
36 #include <asm/hypervisor.h>
37 #endif
38 
39 struct drm_i915_private;
40 
41 #ifndef MISSING_CASE
42 #define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \
43 			     __stringify(x), (long)(x))
44 #endif
45 
46 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
47 
48 int __i915_inject_probe_error(struct drm_i915_private *i915, int err,
49 			      const char *func, int line);
50 #define i915_inject_probe_error(_i915, _err) \
51 	__i915_inject_probe_error((_i915), (_err), __func__, __LINE__)
52 bool i915_error_injected(void);
53 
54 #else
55 
56 #define i915_inject_probe_error(i915, e) ({ BUILD_BUG_ON_INVALID(i915); 0; })
57 #define i915_error_injected() false
58 
59 #endif
60 
61 #define i915_inject_probe_failure(i915) i915_inject_probe_error((i915), -ENODEV)
62 
63 #define i915_probe_error(i915, fmt, ...) ({ \
64 	if (i915_error_injected()) \
65 		drm_dbg(&(i915)->drm, fmt, ##__VA_ARGS__); \
66 	else \
67 		drm_err(&(i915)->drm, fmt, ##__VA_ARGS__); \
68 })
69 
70 #ifndef fetch_and_zero
71 #define fetch_and_zero(ptr) ({						\
72 	typeof(*ptr) __T = *(ptr);					\
73 	*(ptr) = (typeof(*ptr))0;					\
74 	__T;								\
75 })
76 #endif
77 
78 /*
79  * check_user_mbz: Check that a user value exists and is zero
80  *
81  * Frequently in our uABI we reserve space for future extensions, and
82  * two ensure that userspace is prepared we enforce that space must
83  * be zero. (Then any future extension can safely assume a default value
84  * of 0.)
85  *
86  * check_user_mbz() combines checking that the user pointer is accessible
87  * and that the contained value is zero.
88  *
89  * Returns: -EFAULT if not accessible, -EINVAL if !zero, or 0 on success.
90  */
91 #define check_user_mbz(U) ({						\
92 	typeof(*(U)) mbz__;						\
93 	get_user(mbz__, (U)) ? -EFAULT : mbz__ ? -EINVAL : 0;		\
94 })
95 
96 #define __mask_next_bit(mask) ({					\
97 	int __idx = ffs(mask) - 1;					\
98 	mask &= ~BIT(__idx);						\
99 	__idx;								\
100 })
101 
102 static inline bool is_power_of_2_u64(u64 n)
103 {
104 	return (n != 0 && ((n & (n - 1)) == 0));
105 }
106 
107 void add_taint_for_CI(struct drm_i915_private *i915, unsigned int taint);
108 static inline void __add_taint_for_CI(unsigned int taint)
109 {
110 	/*
111 	 * The system is "ok", just about surviving for the user, but
112 	 * CI results are now unreliable as the HW is very suspect.
113 	 * CI checks the taint state after every test and will reboot
114 	 * the machine if the kernel is tainted.
115 	 */
116 	add_taint(taint, LOCKDEP_STILL_OK);
117 }
118 
119 static inline bool i915_run_as_guest(void)
120 {
121 #if IS_ENABLED(CONFIG_X86)
122 	return !hypervisor_is_type(X86_HYPER_NATIVE);
123 #else
124 	/* Not supported yet */
125 	return false;
126 #endif
127 }
128 
129 bool i915_vtd_active(struct drm_i915_private *i915);
130 
131 bool i915_direct_stolen_access(struct drm_i915_private *i915);
132 
133 #endif /* !__I915_UTILS_H */
134