1 /*
2  * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include "hardware/timer.h"
8 #if defined(__unix__) || defined(__APPLE__)
9 #include <unistd.h>
10 #include <sys/time.h>
11 #include <time.h>
12 
13 #endif
14 
15 // in our case not a busy wait
PICO_WEAK_FUNCTION_DEF(busy_wait_us_32)16 PICO_WEAK_FUNCTION_DEF(busy_wait_us_32)
17 void PICO_WEAK_FUNCTION_IMPL_NAME(busy_wait_us_32)(uint32_t delay_us) {
18 #if defined(__unix__) || defined(__APPLE__)
19     usleep(delay_us);
20 #else
21     assert(false);
22 #endif
23 }
24 
PICO_WEAK_FUNCTION_DEF(busy_wait_us)25 PICO_WEAK_FUNCTION_DEF(busy_wait_us)
26 void PICO_WEAK_FUNCTION_IMPL_NAME(busy_wait_us)(uint64_t delay_us) {
27     absolute_time_t t;
28     update_us_since_boot(&t, time_us_64() + delay_us);
29     busy_wait_until(t);
30 }
31 
PICO_WEAK_FUNCTION_DEF(busy_wait_ms)32 PICO_WEAK_FUNCTION_DEF(busy_wait_ms)
33 void PICO_WEAK_FUNCTION_IMPL_NAME(busy_wait_ms)(uint32_t delay_ms) {
34 #if defined(__unix__) || defined(__APPLE__)
35     usleep(delay_ms * 1000);
36 #else
37     assert(false);
38 #endif
39 }
40 
41 // this may or may not wrap
PICO_WEAK_FUNCTION_DEF(time_us_64)42 PICO_WEAK_FUNCTION_DEF(time_us_64)
43 uint64_t PICO_WEAK_FUNCTION_IMPL_NAME(time_us_64)() {
44 #if defined(__unix__) || defined(__APPLE__)
45 //    struct timeval tv;
46 //    gettimeofday(&tv, NULL);
47 //    return tv.tv_sec * (uint64_t) 1000000 + tv.tv_usec;
48     struct timespec ts;
49     clock_gettime(CLOCK_MONOTONIC, &ts);
50     return ts.tv_sec * (uint64_t) 1000000 + ts.tv_nsec / 1000;
51 #else
52     panic_unsupported();
53 #endif
54 }
55 
PICO_WEAK_FUNCTION_DEF(timer_us_32)56 PICO_WEAK_FUNCTION_DEF(timer_us_32)
57 uint32_t PICO_WEAK_FUNCTION_IMPL_NAME(timer_us_32)() {
58     return (uint32_t) time_us_64();
59 }
60 
PICO_WEAK_FUNCTION_DEF(time_reached)61 PICO_WEAK_FUNCTION_DEF(time_reached)
62 bool PICO_WEAK_FUNCTION_IMPL_NAME(time_reached)(absolute_time_t t) {
63     uint64_t target = to_us_since_boot(t);
64     return time_us_64() >= target;
65 }
66 
PICO_WEAK_FUNCTION_DEF(busy_wait_until)67 PICO_WEAK_FUNCTION_DEF(busy_wait_until)
68 void PICO_WEAK_FUNCTION_IMPL_NAME(busy_wait_until)(absolute_time_t target) {
69 #if defined(__unix__)
70     struct timespec tspec;
71     tspec.tv_sec = to_us_since_boot(target) / 1000000;
72     tspec.tv_nsec = (to_us_since_boot(target) % 1000000) * 1000;
73     clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &tspec, NULL);
74 #else
75     const int chunk = 1u<<30u;
76     uint64_t target_us = to_us_since_boot(target);
77     uint64_t time_us = time_us_64();
78     while ((int64_t)(target_us - time_us) >= chunk) {
79         busy_wait_us_32(chunk);
80         time_us = time_us_64();
81     }
82     if (target_us > time_us) {
83         busy_wait_us_32(target_us - time_us);
84     }
85 #endif
86 }
87 
88 static uint8_t claimed_alarms;
89 
hardware_alarm_claim(uint alarm_num)90 void hardware_alarm_claim(uint alarm_num) {
91     assert(!(claimed_alarms & (1u << alarm_num)));
92     claimed_alarms |= 1u <<alarm_num;
93 }
94 
hardware_alarm_unclaim(uint alarm_num)95 void hardware_alarm_unclaim(uint alarm_num) {
96     assert(claimed_alarms & (1u << alarm_num));
97     claimed_alarms &= ~(1u <<alarm_num);
98 }
99 
hardware_alarm_claim_unused(bool required)100 int hardware_alarm_claim_unused(bool required) {
101     int alarm_id = claimed_alarms ? __builtin_clz(~claimed_alarms) : 1;
102     if (alarm_id >= NUM_ALARMS) return -1;
103     claimed_alarms |= 1u << alarm_id;
104     return alarm_id;
105 }
106 
PICO_WEAK_FUNCTION_DEF(hardware_alarm_set_callback)107 PICO_WEAK_FUNCTION_DEF(hardware_alarm_set_callback)
108 void PICO_WEAK_FUNCTION_IMPL_NAME(hardware_alarm_set_callback)(uint alarm_num, hardware_alarm_callback_t callback) {
109     panic_unsupported();
110 }
111 
PICO_WEAK_FUNCTION_DEF(hardware_alarm_set_target)112 PICO_WEAK_FUNCTION_DEF(hardware_alarm_set_target)
113 bool PICO_WEAK_FUNCTION_IMPL_NAME(hardware_alarm_set_target)(uint alarm_num, absolute_time_t target) {
114     panic_unsupported();
115 }
116 
PICO_WEAK_FUNCTION_DEF(hardware_alarm_cancel)117 PICO_WEAK_FUNCTION_DEF(hardware_alarm_cancel)
118 void PICO_WEAK_FUNCTION_IMPL_NAME(hardware_alarm_cancel)(uint alarm_num) {
119     panic_unsupported();
120 }
121 
PICO_WEAK_FUNCTION_DEF(hardware_alarm_force_irq)122 PICO_WEAK_FUNCTION_DEF(hardware_alarm_force_irq)
123 void PICO_WEAK_FUNCTION_IMPL_NAME(hardware_alarm_force_irq)(uint alarm_num) {
124     panic_unsupported();
125 }
126