1 /*
2 * Copyright (c) 2021 NXP
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #define DT_DRV_COMPAT nxp_os_timer
8
9 #include <drivers/timer/system_timer.h>
10 #include <sys_clock.h>
11 #include <spinlock.h>
12 #include "fsl_ostimer.h"
13 #include "fsl_power.h"
14
15 #define CYC_PER_TICK ((uint32_t)((uint64_t)sys_clock_hw_cycles_per_sec() \
16 / (uint64_t)CONFIG_SYS_CLOCK_TICKS_PER_SEC))
17 #define MAX_CYC INT_MAX
18 #define MAX_TICKS ((MAX_CYC - CYC_PER_TICK) / CYC_PER_TICK)
19 #define MIN_DELAY 1000
20
21 #define TICKLESS IS_ENABLED(CONFIG_TICKLESS_KERNEL)
22
23 static struct k_spinlock lock;
24 static uint64_t last_count;
25 static OSTIMER_Type *base;
26
mcux_lpc_ostick_isr(void * arg)27 void mcux_lpc_ostick_isr(void *arg)
28 {
29 ARG_UNUSED(arg);
30
31 k_spinlock_key_t key = k_spin_lock(&lock);
32 uint64_t now = OSTIMER_GetCurrentTimerValue(base);
33 uint32_t dticks = (uint32_t)((now - last_count) / CYC_PER_TICK);
34
35 /* Clear interrupt flag by writing 1. */
36 base->OSEVENT_CTRL &= ~OSTIMER_OSEVENT_CTRL_OSTIMER_INTENA_MASK;
37
38 last_count += dticks * CYC_PER_TICK;
39
40 if (!TICKLESS) {
41 uint64_t next = last_count + CYC_PER_TICK;
42
43 if ((int64_t)(next - now) < MIN_DELAY) {
44 next += CYC_PER_TICK;
45 }
46 OSTIMER_SetMatchValue(base, next, NULL);
47 }
48
49 k_spin_unlock(&lock, key);
50 sys_clock_announce(IS_ENABLED(CONFIG_TICKLESS_KERNEL) ? dticks : 1);
51 }
52
sys_clock_driver_init(const struct device * device)53 int sys_clock_driver_init(const struct device *device)
54 {
55 ARG_UNUSED(device);
56
57 /* Configure event timer's ISR */
58 IRQ_CONNECT(DT_INST_IRQN(0), DT_INST_IRQ(0, priority),
59 mcux_lpc_ostick_isr, NULL, 0);
60
61 base = (OSTIMER_Type *)DT_INST_REG_ADDR(0);
62
63 EnableDeepSleepIRQ(DT_INST_IRQN(0));
64
65 /* Initialize the OS timer, setting clock configuration. */
66 OSTIMER_Init(base);
67
68 last_count = OSTIMER_GetCurrentTimerValue(base);
69 OSTIMER_SetMatchValue(base, last_count + CYC_PER_TICK, NULL);
70
71 /* Enable event timer interrupt */
72 irq_enable(DT_INST_IRQN(0));
73
74 return 0;
75 }
76
sys_clock_set_timeout(int32_t ticks,bool idle)77 void sys_clock_set_timeout(int32_t ticks, bool idle)
78 {
79 ARG_UNUSED(idle);
80
81 if (!IS_ENABLED(CONFIG_TICKLESS_KERNEL)) {
82 /* Only for tickless kernel system */
83 return;
84 }
85
86 ticks = ticks == K_TICKS_FOREVER ? MAX_TICKS : ticks;
87 ticks = CLAMP(ticks - 1, 0, (int32_t)MAX_TICKS);
88
89 k_spinlock_key_t key = k_spin_lock(&lock);
90 uint64_t now = OSTIMER_GetCurrentTimerValue(base);
91 uint32_t adj, cyc = ticks * CYC_PER_TICK;
92
93 /* Round up to next tick boundary. */
94 adj = (uint32_t)(now - last_count) + (CYC_PER_TICK - 1);
95 if (cyc <= MAX_CYC - adj) {
96 cyc += adj;
97 } else {
98 cyc = MAX_CYC;
99 }
100 cyc = (cyc / CYC_PER_TICK) * CYC_PER_TICK;
101
102 if ((int32_t)(cyc + last_count - now) < MIN_DELAY) {
103 cyc += CYC_PER_TICK;
104 }
105
106 OSTIMER_SetMatchValue(base, cyc + last_count, NULL);
107
108 k_spin_unlock(&lock, key);
109 }
110
sys_clock_elapsed(void)111 uint32_t sys_clock_elapsed(void)
112 {
113 if (!IS_ENABLED(CONFIG_TICKLESS_KERNEL)) {
114 /* Always return 0 for tickful kernel system */
115 return 0;
116 }
117
118 k_spinlock_key_t key = k_spin_lock(&lock);
119 uint32_t ret = ((uint32_t)OSTIMER_GetCurrentTimerValue(base) -
120 (uint32_t)last_count) / CYC_PER_TICK;
121
122 k_spin_unlock(&lock, key);
123 return ret;
124 }
125
sys_clock_cycle_get_32(void)126 uint32_t sys_clock_cycle_get_32(void)
127 {
128 return (uint32_t)OSTIMER_GetCurrentTimerValue(base);
129 }
130
