linux/arch/riscv/include/asm/timex.h
Palmer Dabbelt 6d60b6ee0c RISC-V: Device, timer, IRQs, and the SBI
This patch contains code that interfaces with devices that are mandated
by the RISC-V supervisor specification and that don't have explicit
drivers anywhere else in the tree.  This includes the staticly defined
interrupts, the CSR-mapped timer, and virtualized SBI devices.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2017-09-26 15:26:47 -07:00

60 lines
1.3 KiB
C

/*
* Copyright (C) 2012 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _ASM_RISCV_TIMEX_H
#define _ASM_RISCV_TIMEX_H
#include <asm/param.h>
typedef unsigned long cycles_t;
static inline cycles_t get_cycles(void)
{
cycles_t n;
__asm__ __volatile__ (
"rdtime %0"
: "=r" (n));
return n;
}
#ifdef CONFIG_64BIT
static inline uint64_t get_cycles64(void)
{
return get_cycles();
}
#else
static inline uint64_t get_cycles64(void)
{
u32 lo, hi, tmp;
__asm__ __volatile__ (
"1:\n"
"rdtimeh %0\n"
"rdtime %1\n"
"rdtimeh %2\n"
"bne %0, %2, 1b"
: "=&r" (hi), "=&r" (lo), "=&r" (tmp));
return ((u64)hi << 32) | lo;
}
#endif
#define ARCH_HAS_READ_CURRENT_TIMER
static inline int read_current_timer(unsigned long *timer_val)
{
*timer_val = get_cycles();
return 0;
}
#endif /* _ASM_RISCV_TIMEX_H */