1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * RISC-V Arch Timer(sstc) specific interface
4 *
5 * Copyright (c) 2024 Intel Corporation
6 */
7
8 #ifndef SELFTEST_KVM_ARCH_TIMER_H
9 #define SELFTEST_KVM_ARCH_TIMER_H
10
11 #include <asm/csr.h>
12 #include <asm/vdso/processor.h>
13
14 static unsigned long timer_freq;
15
16 #define msec_to_cycles(msec) \
17 ((timer_freq) * (uint64_t)(msec) / 1000)
18
19 #define usec_to_cycles(usec) \
20 ((timer_freq) * (uint64_t)(usec) / 1000000)
21
22 #define cycles_to_usec(cycles) \
23 ((uint64_t)(cycles) * 1000000 / (timer_freq))
24
25 static inline uint64_t timer_get_cycles(void)
26 {
27 return csr_read(CSR_TIME);
28 }
29
30 static inline void timer_set_cmp(uint64_t cval)
31 {
32 csr_write(CSR_STIMECMP, cval);
33 }
34
35 static inline uint64_t timer_get_cmp(void)
36 {
37 return csr_read(CSR_STIMECMP);
38 }
39
40 static inline void timer_irq_enable(void)
41 {
42 csr_set(CSR_SIE, IE_TIE);
43 }
44
45 static inline void timer_irq_disable(void)
46 {
47 csr_clear(CSR_SIE, IE_TIE);
48 }
49
50 static inline void timer_set_next_cmp_ms(uint32_t msec)
51 {
52 uint64_t now_ct = timer_get_cycles();
53 uint64_t next_ct = now_ct + msec_to_cycles(msec);
54
55 timer_set_cmp(next_ct);
56 }
57
58 static inline void __delay(uint64_t cycles)
59 {
60 uint64_t start = timer_get_cycles();
61
62 while ((timer_get_cycles() - start) < cycles)
63 cpu_relax();
64 }
65
66 static inline void udelay(unsigned long usec)
67 {
68 __delay(usec_to_cycles(usec));
69 }
70
71 #endif /* SELFTEST_KVM_ARCH_TIMER_H */
72
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.