27 lines
797 B
C
27 lines
797 B
C
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (C) 2020 Google, Inc
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*/
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#ifndef _ASM_RISCV_CLINT_H
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#define _ASM_RISCV_CLINT_H
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#include <linux/types.h>
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#include <asm/mmio.h>
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#ifdef CONFIG_RISCV_M_MODE
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/*
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* This lives in the CLINT driver, but is accessed directly by timex.h to avoid
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* any overhead when accessing the MMIO timer.
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*
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* The ISA defines mtime as a 64-bit memory-mapped register that increments at
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* a constant frequency, but it doesn't define some other constraints we depend
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* on (most notably ordering constraints, but also some simpler stuff like the
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* memory layout). Thus, this is called "clint_time_val" instead of something
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* like "riscv_mtime", to signify that these non-ISA assumptions must hold.
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*/
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extern u64 __iomem *clint_time_val;
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#endif
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#endif
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