/
litex_timer.c
101 lines (78 loc) · 2.68 KB
/
litex_timer.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
/*
* Copyright (c) 2018 - 2019 Antmicro <www.antmicro.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT litex_timer0
#include <zephyr/kernel.h>
#include <zephyr/arch/cpu.h>
#include <zephyr/init.h>
#include <zephyr/irq.h>
#include <zephyr/spinlock.h>
#include <zephyr/drivers/timer/system_timer.h>
#include <soc.h>
#define TIMER_LOAD_ADDR DT_INST_REG_ADDR_BY_NAME(0, load)
#define TIMER_RELOAD_ADDR DT_INST_REG_ADDR_BY_NAME(0, reload)
#define TIMER_EN_ADDR DT_INST_REG_ADDR_BY_NAME(0, en)
#define TIMER_UPDATE_VALUE_ADDR DT_INST_REG_ADDR_BY_NAME(0, update_value)
#define TIMER_VALUE_ADDR DT_INST_REG_ADDR_BY_NAME(0, value)
#define TIMER_EV_STATUS_ADDR DT_INST_REG_ADDR_BY_NAME(0, ev_status)
#define TIMER_EV_PENDING_ADDR DT_INST_REG_ADDR_BY_NAME(0, ev_pending)
#define TIMER_EV_ENABLE_ADDR DT_INST_REG_ADDR_BY_NAME(0, ev_enable)
#define TIMER_UPTIME_LATCH_ADDR DT_INST_REG_ADDR_BY_NAME(0, uptime_latch)
#define TIMER_UPTIME_CYCLES_ADDR DT_INST_REG_ADDR_BY_NAME(0, uptime_cycles)
#define TIMER_EV 0x1
#define TIMER_IRQ DT_INST_IRQN(0)
#define TIMER_DISABLE 0x0
#define TIMER_ENABLE 0x1
#define TIMER_UPTIME_LATCH 0x1
#if defined(CONFIG_TEST)
const int32_t z_sys_timer_irq_for_test = TIMER_IRQ;
#endif
static void litex_timer_irq_handler(const void *device)
{
unsigned int key = irq_lock();
litex_write8(TIMER_EV, TIMER_EV_PENDING_ADDR);
sys_clock_announce(1);
irq_unlock(key);
}
uint32_t sys_clock_cycle_get_32(void)
{
static struct k_spinlock lock;
uint32_t uptime_cycles;
k_spinlock_key_t key = k_spin_lock(&lock);
litex_write8(TIMER_UPTIME_LATCH, TIMER_UPTIME_LATCH_ADDR);
uptime_cycles = (uint32_t)litex_read64(TIMER_UPTIME_CYCLES_ADDR);
k_spin_unlock(&lock, key);
return uptime_cycles;
}
uint64_t sys_clock_cycle_get_64(void)
{
static struct k_spinlock lock;
uint64_t uptime_cycles;
k_spinlock_key_t key = k_spin_lock(&lock);
litex_write8(TIMER_UPTIME_LATCH, TIMER_UPTIME_LATCH_ADDR);
uptime_cycles = litex_read64(TIMER_UPTIME_CYCLES_ADDR);
k_spin_unlock(&lock, key);
return uptime_cycles;
}
/* tickless kernel is not supported */
uint32_t sys_clock_elapsed(void)
{
return 0;
}
static int sys_clock_driver_init(void)
{
IRQ_CONNECT(TIMER_IRQ, DT_INST_IRQ(0, priority),
litex_timer_irq_handler, NULL, 0);
irq_enable(TIMER_IRQ);
litex_write8(TIMER_DISABLE, TIMER_EN_ADDR);
litex_write32(k_ticks_to_cyc_floor32(1), TIMER_RELOAD_ADDR);
litex_write32(k_ticks_to_cyc_floor32(1), TIMER_LOAD_ADDR);
litex_write8(TIMER_ENABLE, TIMER_EN_ADDR);
litex_write8(litex_read8(TIMER_EV_PENDING_ADDR), TIMER_EV_PENDING_ADDR);
litex_write8(TIMER_EV, TIMER_EV_ENABLE_ADDR);
return 0;
}
SYS_INIT(sys_clock_driver_init, PRE_KERNEL_2,
CONFIG_SYSTEM_CLOCK_INIT_PRIORITY);