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