drivers/gpu/drm/i915/i915_fixed.h

   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
  20 static inline bool is_fixed16_zero(uint_fixed_16_16_t val)
  21 {
  22         return val.val == 0;
  23 }
  24
  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
  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
  39 static inline u32 fixed16_to_u32(uint_fixed_16_16_t fp)
  40 {
  41         return fp.val >> 16;
  42 }
  43
  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
  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
  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
  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
  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
  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
  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
 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
 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
 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
 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_ */