xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/i915/i915_fixed.h (revision 41ec02673d281bbb3d38e6c78504ce6e30c228c1)
1 /*	$NetBSD: i915_fixed.h,v 1.2 2021/12/18 23:45:28 riastradh Exp $	*/
2 
3 /* SPDX-License-Identifier: MIT */
4 /*
5  * Copyright © 2018 Intel Corporation
6  */
7 
8 #ifndef _I915_FIXED_H_
9 #define _I915_FIXED_H_
10 
11 #include <linux/bug.h>
12 #include <linux/kernel.h>
13 #include <linux/math64.h>
14 #include <linux/types.h>
15 
16 typedef struct {
17 	u32 val;
18 } uint_fixed_16_16_t;
19 
20 #define FP_16_16_MAX ((uint_fixed_16_16_t){ .val = UINT_MAX })
21 
is_fixed16_zero(uint_fixed_16_16_t val)22 static inline bool is_fixed16_zero(uint_fixed_16_16_t val)
23 {
24 	return val.val == 0;
25 }
26 
u32_to_fixed16(u32 val)27 static inline uint_fixed_16_16_t u32_to_fixed16(u32 val)
28 {
29 	uint_fixed_16_16_t fp = { .val = val << 16 };
30 
31 	WARN_ON(val > U16_MAX);
32 
33 	return fp;
34 }
35 
fixed16_to_u32_round_up(uint_fixed_16_16_t fp)36 static inline u32 fixed16_to_u32_round_up(uint_fixed_16_16_t fp)
37 {
38 	return DIV_ROUND_UP(fp.val, 1 << 16);
39 }
40 
fixed16_to_u32(uint_fixed_16_16_t fp)41 static inline u32 fixed16_to_u32(uint_fixed_16_16_t fp)
42 {
43 	return fp.val >> 16;
44 }
45 
min_fixed16(uint_fixed_16_16_t min1,uint_fixed_16_16_t min2)46 static inline uint_fixed_16_16_t min_fixed16(uint_fixed_16_16_t min1,
47 					     uint_fixed_16_16_t min2)
48 {
49 	uint_fixed_16_16_t min = { .val = min(min1.val, min2.val) };
50 
51 	return min;
52 }
53 
max_fixed16(uint_fixed_16_16_t max1,uint_fixed_16_16_t max2)54 static inline uint_fixed_16_16_t max_fixed16(uint_fixed_16_16_t max1,
55 					     uint_fixed_16_16_t max2)
56 {
57 	uint_fixed_16_16_t max = { .val = max(max1.val, max2.val) };
58 
59 	return max;
60 }
61 
clamp_u64_to_fixed16(u64 val)62 static inline uint_fixed_16_16_t clamp_u64_to_fixed16(u64 val)
63 {
64 	uint_fixed_16_16_t fp = { .val = (u32)val };
65 
66 	WARN_ON(val > U32_MAX);
67 
68 	return fp;
69 }
70 
div_round_up_fixed16(uint_fixed_16_16_t val,uint_fixed_16_16_t d)71 static inline u32 div_round_up_fixed16(uint_fixed_16_16_t val,
72 				       uint_fixed_16_16_t d)
73 {
74 	return DIV_ROUND_UP(val.val, d.val);
75 }
76 
mul_round_up_u32_fixed16(u32 val,uint_fixed_16_16_t mul)77 static inline u32 mul_round_up_u32_fixed16(u32 val, uint_fixed_16_16_t mul)
78 {
79 	u64 tmp;
80 
81 	tmp = mul_u32_u32(val, mul.val);
82 	tmp = DIV_ROUND_UP_ULL(tmp, 1 << 16);
83 	WARN_ON(tmp > U32_MAX);
84 
85 	return (u32)tmp;
86 }
87 
mul_fixed16(uint_fixed_16_16_t val,uint_fixed_16_16_t mul)88 static inline uint_fixed_16_16_t mul_fixed16(uint_fixed_16_16_t val,
89 					     uint_fixed_16_16_t mul)
90 {
91 	u64 tmp;
92 
93 	tmp = mul_u32_u32(val.val, mul.val);
94 	tmp = tmp >> 16;
95 
96 	return clamp_u64_to_fixed16(tmp);
97 }
98 
div_fixed16(u32 val,u32 d)99 static inline uint_fixed_16_16_t div_fixed16(u32 val, u32 d)
100 {
101 	u64 tmp;
102 
103 	tmp = (u64)val << 16;
104 	tmp = DIV_ROUND_UP_ULL(tmp, d);
105 
106 	return clamp_u64_to_fixed16(tmp);
107 }
108 
div_round_up_u32_fixed16(u32 val,uint_fixed_16_16_t d)109 static inline u32 div_round_up_u32_fixed16(u32 val, uint_fixed_16_16_t d)
110 {
111 	u64 tmp;
112 
113 	tmp = (u64)val << 16;
114 	tmp = DIV_ROUND_UP_ULL(tmp, d.val);
115 	WARN_ON(tmp > U32_MAX);
116 
117 	return (u32)tmp;
118 }
119 
mul_u32_fixed16(u32 val,uint_fixed_16_16_t mul)120 static inline uint_fixed_16_16_t mul_u32_fixed16(u32 val, uint_fixed_16_16_t mul)
121 {
122 	u64 tmp;
123 
124 	tmp = mul_u32_u32(val, mul.val);
125 
126 	return clamp_u64_to_fixed16(tmp);
127 }
128 
add_fixed16(uint_fixed_16_16_t add1,uint_fixed_16_16_t add2)129 static inline uint_fixed_16_16_t add_fixed16(uint_fixed_16_16_t add1,
130 					     uint_fixed_16_16_t add2)
131 {
132 	u64 tmp;
133 
134 	tmp = (u64)add1.val + add2.val;
135 
136 	return clamp_u64_to_fixed16(tmp);
137 }
138 
add_fixed16_u32(uint_fixed_16_16_t add1,u32 add2)139 static inline uint_fixed_16_16_t add_fixed16_u32(uint_fixed_16_16_t add1,
140 						 u32 add2)
141 {
142 	uint_fixed_16_16_t tmp_add2 = u32_to_fixed16(add2);
143 	u64 tmp;
144 
145 	tmp = (u64)add1.val + tmp_add2.val;
146 
147 	return clamp_u64_to_fixed16(tmp);
148 }
149 
150 #endif /* _I915_FIXED_H_ */
151