From 6fca8abef7e6d7be1a9e6d93dd0f2b7fbc5b28e5 Mon Sep 17 00:00:00 2001 From: Pasha Date: Tue, 20 Feb 2024 18:55:36 +0000 Subject: initial risc-v example --- riscv/include/asm/clint.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) create mode 100644 riscv/include/asm/clint.h (limited to 'riscv/include/asm/clint.h') diff --git a/riscv/include/asm/clint.h b/riscv/include/asm/clint.h new file mode 100644 index 0000000..0789fd3 --- /dev/null +++ b/riscv/include/asm/clint.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2020 Google, Inc + */ + +#ifndef _ASM_RISCV_CLINT_H +#define _ASM_RISCV_CLINT_H + +#include +#include + +#ifdef CONFIG_RISCV_M_MODE +/* + * This lives in the CLINT driver, but is accessed directly by timex.h to avoid + * any overhead when accessing the MMIO timer. + * + * The ISA defines mtime as a 64-bit memory-mapped register that increments at + * a constant frequency, but it doesn't define some other constraints we depend + * on (most notably ordering constraints, but also some simpler stuff like the + * memory layout). Thus, this is called "clint_time_val" instead of something + * like "riscv_mtime", to signify that these non-ISA assumptions must hold. + */ +extern u64 __iomem *clint_time_val; +#endif + +#endif -- cgit v1.2.1