1 /*
2 * Copyright (c) 2018 Travis Geiselbrecht
3 *
4 * Use of this source code is governed by a MIT-style
5 * license that can be found in the LICENSE file or at
6 * https://opensource.org/licenses/MIT
7 */
8 #include <lk/reg.h>
9 #include <lk/debug.h>
10 #include <lk/trace.h>
11 #include <lk/err.h>
12 #include <lk/trace.h>
13
14 #include <arch/riscv/feature.h>
15
16 #include <arch/riscv.h>
17 #include <arch/ops.h>
18
19 #include <platform.h>
20 #include <platform/timer.h>
21
22 #define LOCAL_TRACE 0
23
24 static platform_timer_callback timer_cb;
25 static void *timer_arg;
26
platform_set_oneshot_timer(platform_timer_callback callback,void * arg,lk_time_t interval)27 status_t platform_set_oneshot_timer (platform_timer_callback callback, void *arg, lk_time_t interval) {
28 LTRACEF("cb %p, arg %p, interval %u\n", callback, arg, interval);
29
30 // disable timer
31 riscv_csr_clear(RISCV_CSR_XIE, RISCV_CSR_XIE_TIE);
32
33 timer_cb = callback;
34 timer_arg = arg;
35
36 // enable the timer
37 riscv_csr_set(RISCV_CSR_XIE, RISCV_CSR_XIE_TIE);
38
39 // convert interval to ticks
40 uint64_t ticks = riscv_get_time() + ((interval * ARCH_RISCV_MTIME_RATE) / 1000u);
41 #if RISCV_M_MODE
42 clint_set_timer(ticks);
43 #elif RISCV_S_MODE
44 if (riscv_feature_test(RISCV_FEAT_SSTC)) {
45 #if __riscv_xlen == 64
46 riscv_csr_write(RISCV_CSR_STIMECMP, ticks);
47 #else
48 riscv_csr_write(RISCV_CSR_STIMECMPH, ticks >> 32);
49 riscv_csr_write(RISCV_CSR_STIMECMP, ticks);
50 #endif
51 } else {
52 sbi_set_timer(ticks);
53 }
54 #endif
55
56 return NO_ERROR;
57 }
58
59
current_time_hires(void)60 lk_bigtime_t current_time_hires(void) {
61 #if ARCH_RISCV_MTIME_RATE < 10000000
62 return current_time() * 1000llu; // hack to deal with slow clocks
63 #else
64 return riscv_get_time() / (ARCH_RISCV_MTIME_RATE / 1000000u);
65 #endif
66 }
67
current_time(void)68 lk_time_t current_time(void) {
69 return riscv_get_time() / (ARCH_RISCV_MTIME_RATE / 1000u);
70 }
71
platform_stop_timer(void)72 void platform_stop_timer(void) {
73 riscv_csr_clear(RISCV_CSR_XIE, RISCV_CSR_XIE_TIE);
74 }
75
riscv_timer_exception(void)76 enum handler_return riscv_timer_exception(void) {
77 LTRACEF("tick\n");
78
79 riscv_csr_clear(RISCV_CSR_XIE, RISCV_CSR_XIE_TIE);
80
81 enum handler_return ret = INT_NO_RESCHEDULE;
82 if (timer_cb) {
83 ret = timer_cb(timer_arg, current_time());
84 }
85
86 return ret;
87 }
88