xref: /openbmc/linux/drivers/gpu/drm/i915/i915_utils.h (revision 2c6467d2)
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 #undef WARN_ON
29 /* Many gcc seem to no see through this and fall over :( */
30 #if 0
31 #define WARN_ON(x) ({ \
32 	bool __i915_warn_cond = (x); \
33 	if (__builtin_constant_p(__i915_warn_cond)) \
34 		BUILD_BUG_ON(__i915_warn_cond); \
35 	WARN(__i915_warn_cond, "WARN_ON(" #x ")"); })
36 #else
37 #define WARN_ON(x) WARN((x), "%s", "WARN_ON(" __stringify(x) ")")
38 #endif
39 
40 #undef WARN_ON_ONCE
41 #define WARN_ON_ONCE(x) WARN_ONCE((x), "%s", "WARN_ON_ONCE(" __stringify(x) ")")
42 
43 #define MISSING_CASE(x) WARN(1, "Missing case (%s == %ld)\n", \
44 			     __stringify(x), (long)(x))
45 
46 #if defined(GCC_VERSION) && GCC_VERSION >= 70000
47 #define add_overflows_t(T, A, B) \
48 	__builtin_add_overflow_p((A), (B), (T)0)
49 #else
50 #define add_overflows_t(T, A, B) ({ \
51 	typeof(A) a = (A); \
52 	typeof(B) b = (B); \
53 	(T)(a + b) < a; \
54 })
55 #endif
56 
57 #define add_overflows(A, B) \
58 	add_overflows_t(typeof((A) + (B)), (A), (B))
59 
60 #define range_overflows(start, size, max) ({ \
61 	typeof(start) start__ = (start); \
62 	typeof(size) size__ = (size); \
63 	typeof(max) max__ = (max); \
64 	(void)(&start__ == &size__); \
65 	(void)(&start__ == &max__); \
66 	start__ > max__ || size__ > max__ - start__; \
67 })
68 
69 #define range_overflows_t(type, start, size, max) \
70 	range_overflows((type)(start), (type)(size), (type)(max))
71 
72 /* Note we don't consider signbits :| */
73 #define overflows_type(x, T) \
74 	(sizeof(x) > sizeof(T) && (x) >> BITS_PER_TYPE(T))
75 
76 #define ptr_mask_bits(ptr, n) ({					\
77 	unsigned long __v = (unsigned long)(ptr);			\
78 	(typeof(ptr))(__v & -BIT(n));					\
79 })
80 
81 #define ptr_unmask_bits(ptr, n) ((unsigned long)(ptr) & (BIT(n) - 1))
82 
83 #define ptr_unpack_bits(ptr, bits, n) ({				\
84 	unsigned long __v = (unsigned long)(ptr);			\
85 	*(bits) = __v & (BIT(n) - 1);					\
86 	(typeof(ptr))(__v & -BIT(n));					\
87 })
88 
89 #define ptr_pack_bits(ptr, bits, n) ({					\
90 	unsigned long __bits = (bits);					\
91 	GEM_BUG_ON(__bits & -BIT(n));					\
92 	((typeof(ptr))((unsigned long)(ptr) | __bits));			\
93 })
94 
95 #define page_mask_bits(ptr) ptr_mask_bits(ptr, PAGE_SHIFT)
96 #define page_unmask_bits(ptr) ptr_unmask_bits(ptr, PAGE_SHIFT)
97 #define page_pack_bits(ptr, bits) ptr_pack_bits(ptr, bits, PAGE_SHIFT)
98 #define page_unpack_bits(ptr, bits) ptr_unpack_bits(ptr, bits, PAGE_SHIFT)
99 
100 #define ptr_offset(ptr, member) offsetof(typeof(*(ptr)), member)
101 
102 #define fetch_and_zero(ptr) ({						\
103 	typeof(*ptr) __T = *(ptr);					\
104 	*(ptr) = (typeof(*ptr))0;					\
105 	__T;								\
106 })
107 
108 static inline u64 ptr_to_u64(const void *ptr)
109 {
110 	return (uintptr_t)ptr;
111 }
112 
113 #define u64_to_ptr(T, x) ({						\
114 	typecheck(u64, x);						\
115 	(T *)(uintptr_t)(x);						\
116 })
117 
118 #define __mask_next_bit(mask) ({					\
119 	int __idx = ffs(mask) - 1;					\
120 	mask &= ~BIT(__idx);						\
121 	__idx;								\
122 })
123 
124 #include <linux/list.h>
125 
126 static inline int list_is_first(const struct list_head *list,
127 				const struct list_head *head)
128 {
129 	return head->next == list;
130 }
131 
132 static inline void __list_del_many(struct list_head *head,
133 				   struct list_head *first)
134 {
135 	first->prev = head;
136 	WRITE_ONCE(head->next, first);
137 }
138 
139 /*
140  * Wait until the work is finally complete, even if it tries to postpone
141  * by requeueing itself. Note, that if the worker never cancels itself,
142  * we will spin forever.
143  */
144 static inline void drain_delayed_work(struct delayed_work *dw)
145 {
146 	do {
147 		while (flush_delayed_work(dw))
148 			;
149 	} while (delayed_work_pending(dw));
150 }
151 
152 static inline const char *yesno(bool v)
153 {
154 	return v ? "yes" : "no";
155 }
156 
157 static inline const char *onoff(bool v)
158 {
159 	return v ? "on" : "off";
160 }
161 
162 static inline const char *enableddisabled(bool v)
163 {
164 	return v ? "enabled" : "disabled";
165 }
166 
167 #endif /* !__I915_UTILS_H */
168