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