LXR linux/arch/riscv/include/asm/clint.h

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * Copyright (C) 2020 Google, Inc
   4 */
   5
   6#ifndef _ASM_RISCV_CLINT_H
   7#define _ASM_RISCV_CLINT_H
   8
   9#include <linux/types.h>
  10#include <asm/mmio.h>
  11
  12#ifdef CONFIG_RISCV_M_MODE
  13/*
  14 * This lives in the CLINT driver, but is accessed directly by timex.h to avoid
  15 * any overhead when accessing the MMIO timer.
  16 *
  17 * The ISA defines mtime as a 64-bit memory-mapped register that increments at
  18 * a constant frequency, but it doesn't define some other constraints we depend
  19 * on (most notably ordering constraints, but also some simpler stuff like the
  20 * memory layout).  Thus, this is called "clint_time_val" instead of something
  21 * like "riscv_mtime", to signify that these non-ISA assumptions must hold.
  22 */
  23extern u64 __iomem *clint_time_val;
  24#endif
  25
  26#endif
  27