1 /*
2 * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #ifndef _HARDWARE_DIVIDER_H
8 #define _HARDWARE_DIVIDER_H
9
10 #include "pico/types.h"
11
12 typedef uint64_t divmod_result_t;
13
__sign_of(int32_t v)14 static inline int __sign_of(int32_t v) {
15 return v > 0 ? 1 : (v < 0 ? -1 : 0);
16 }
17
18 // divides unsigned values a by b... (a/b) returned in low 32 bits, (a%b) in high 32 bits... results undefined for b==0
hw_divider_divmod_u32(uint32_t a,uint32_t b)19 static inline uint64_t hw_divider_divmod_u32(uint32_t a, uint32_t b) {
20 if (!b) return (((uint64_t)a)<<32u) | (uint32_t)(-1); // todo check this
21 return (((uint64_t)(a%b))<<32u) | (a/b);
22 }
23
24 // divides signed values a by b... (a/b) returned in low 32 bits, (a%b) in high 32 bits... results undefined for b==0
hw_divider_divmod_s32(int32_t a,int32_t b)25 static inline uint64_t hw_divider_divmod_s32(int32_t a, int32_t b) {
26 if (!b) return (((uint64_t)a)<<32u) | (uint32_t)(-__sign_of(a));
27 return (((uint64_t)(a%b))<<32u) | (uint32_t)(a/b);
28 }
29
30 extern __thread divmod_result_t hw_divider_result_threadlocal;
31
hw_divider_divmod_s32_start(int32_t a,int32_t b)32 static inline void hw_divider_divmod_s32_start(int32_t a, int32_t b) {
33 hw_divider_result_threadlocal = hw_divider_divmod_s32(a, b);
34 }
35
hw_divider_divmod_u32_start(uint32_t a,uint32_t b)36 static inline void hw_divider_divmod_u32_start(uint32_t a, uint32_t b) {
37 hw_divider_result_threadlocal = hw_divider_divmod_u32(a, b);
38 }
39
hw_divider_result_wait()40 static inline divmod_result_t hw_divider_result_wait() {
41 return hw_divider_result_threadlocal;
42 }
43
hw_divider_result_nowait()44 static inline uint64_t hw_divider_result_nowait() {
45 return hw_divider_result_threadlocal;
46 }
47
to_quotient_u32(unsigned long long int r)48 inline static uint32_t to_quotient_u32(unsigned long long int r) {
49 return (uint32_t) r;
50 }
51
to_quotient_s32(unsigned long long int r)52 inline static int32_t to_quotient_s32(unsigned long long int r) {
53 return (int32_t)(uint32_t)r;
54 }
55
to_remainder_u32(unsigned long long int r)56 inline static uint32_t to_remainder_u32(unsigned long long int r) {
57 return (uint32_t)(r >> 32u);
58 }
59
to_remainder_s32(unsigned long long int r)60 inline static int32_t to_remainder_s32(unsigned long long int r) {
61 return (int32_t)(r >> 32u);
62 }
63
hw_divider_u32_quotient_wait()64 static inline uint32_t hw_divider_u32_quotient_wait() {
65 return to_quotient_u32(hw_divider_result_wait());
66 }
67
hw_divider_u32_remainder_wait()68 static inline uint32_t hw_divider_u32_remainder_wait() {
69 return to_remainder_u32(hw_divider_result_wait());
70 }
71
hw_divider_s32_quotient_wait()72 static inline int32_t hw_divider_s32_quotient_wait() {
73 return to_quotient_s32(hw_divider_result_wait());
74 }
75
hw_divider_s32_remainder_wait()76 static inline int32_t hw_divider_s32_remainder_wait() {
77 return to_remainder_s32(hw_divider_result_wait());
78 }
79
hw_divider_u32_quotient(uint32_t a,uint32_t b)80 static inline uint32_t hw_divider_u32_quotient(uint32_t a, uint32_t b) {
81 return b ? (a / b) : (uint32_t)(-1);
82 }
83
hw_divider_u32_remainder(uint32_t a,uint32_t b)84 static inline uint32_t hw_divider_u32_remainder(uint32_t a, uint32_t b) {
85 return b ? (a % b) : a;
86 }
87
hw_divider_s32_quotient(int32_t a,int32_t b)88 static inline int32_t hw_divider_s32_quotient(int32_t a, int32_t b) {
89 return b ? (a / b) : -__sign_of(a);
90 }
91
hw_divider_s32_remainder(int32_t a,int32_t b)92 static inline int32_t hw_divider_s32_remainder(int32_t a, int32_t b) {
93 return b ? (a % b) : a;
94 }
95
hw_divider_u32_quotient_inlined(uint32_t a,uint32_t b)96 static inline uint32_t hw_divider_u32_quotient_inlined(uint32_t a, uint32_t b) {
97 return hw_divider_u32_quotient(a,b);
98 }
99
hw_divider_u32_remainder_inlined(uint32_t a,uint32_t b)100 static inline uint32_t hw_divider_u32_remainder_inlined(uint32_t a, uint32_t b) {
101 return hw_divider_u32_remainder(a,b);
102 }
103
hw_divider_s32_quotient_inlined(int32_t a,int32_t b)104 static inline int32_t hw_divider_s32_quotient_inlined(int32_t a, int32_t b) {
105 return hw_divider_s32_quotient(a,b);
106 }
107
hw_divider_s32_remainder_inlined(int32_t a,int32_t b)108 static inline int32_t hw_divider_s32_remainder_inlined(int32_t a, int32_t b) {
109 return hw_divider_s32_remainder(a,b);
110 }
111
112 typedef uint64_t hw_divider_state_t;
113
hw_divider_save_state(hw_divider_state_t * dest)114 static inline void hw_divider_save_state(hw_divider_state_t *dest) {
115 *dest = hw_divider_result_threadlocal;
116 }
117
hw_divider_restore_state(hw_divider_state_t * src)118 static inline void hw_divider_restore_state(hw_divider_state_t *src) {
119 hw_divider_result_threadlocal = *src;
120 }
121
122 #endif // _HARDWARE_DIVIDER_H
123
