Files
linux/arch/riscv/include/asm/timex.h
T
Thomas Gleixner dfc256dac5 calibrate: Rework delay timer calibration
The header define in asm/timex,h and the naming of the function to read the
delay timer are confusing at best.

Convert it to a config switch selected by the archictures which provide the
functionality and rename the function to delay_read_timer(), which makes
the purpose clear. Move the declaration to linux/delay.h where it belongs.

Remove the resulting empty asm/timex.h files as well.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260410120317.978403520@kernel.org
2026-07-15 15:04:55 +02:00

84 lines
1.6 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 */
#endif /* _ASM_RISCV_TIMEX_H */