kernel/arch/riscv/include/asm/timex.h
2024-07-22 17:22:30 +08:00

94 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 Regents of the University of California
*/
#ifndef _ASM_RISCV_TIMEX_H
#define _ASM_RISCV_TIMEX_H
#include <asm/csr.h>
typedef unsigned long cycles_t;
#ifdef CONFIG_RISCV_M_MODE
#include <asm/clint.h>
#ifdef CONFIG_64BIT
static inline cycles_t get_cycles(void)
{
return readq_relaxed(clint_time_val);
}
#else /* !CONFIG_64BIT */
static inline u32 get_cycles(void)
{
return readl_relaxed(((u32 *)clint_time_val));
}
#define get_cycles get_cycles
static inline u32 get_cycles_hi(void)
{
return readl_relaxed(((u32 *)clint_time_val) + 1);
}
#define get_cycles_hi get_cycles_hi
#endif /* CONFIG_64BIT */
/*
* Much like MIPS, we may not have a viable counter to use at an early point
* in the boot process. Unfortunately we don't have a fallback, so instead
* we just return 0.
*/
static inline unsigned long random_get_entropy(void)
{
if (unlikely(clint_time_val == NULL))
return random_get_entropy_fallback();
return get_cycles();
}
#define random_get_entropy() random_get_entropy()
#else /* CONFIG_RISCV_M_MODE */
static inline cycles_t get_cycles(void)
{
return csr_read(CSR_TIME);
}
#define get_cycles get_cycles
static inline u32 get_cycles_hi(void)
{
return csr_read(CSR_TIMEH);
}
#define get_cycles_hi get_cycles_hi
#endif /* !CONFIG_RISCV_M_MODE */
#ifdef CONFIG_64BIT
static inline u64 get_cycles64(void)
{
return get_cycles();
}
#else /* CONFIG_64BIT */
static inline u64 get_cycles64(void)
{
u32 hi, lo;
do {
hi = get_cycles_hi();
lo = get_cycles();
} while (hi != get_cycles_hi());
return ((u64)hi << 32) | lo;
}
#endif /* CONFIG_64BIT */
#define ARCH_HAS_READ_CURRENT_TIMER
static inline int read_current_timer(unsigned long *timer_val)
{
*timer_val = get_cycles();
return 0;
}
extern void time_init(void);
#endif /* _ASM_RISCV_TIMEX_H */