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1/* SPDX-License-Identifier: GPL-2.0-only */
2#ifndef __ASM_VDSO_PROCESSOR_H
3#define __ASM_VDSO_PROCESSOR_H
4
5#ifndef __ASSEMBLER__
6
7#include <asm/barrier.h>
8#include <asm/errata_list.h>
9#include <asm/insn-def.h>
10
11static inline void cpu_relax(void)
12{
13#ifdef __riscv_muldiv
14 int dummy;
15 /* In lieu of a halt instruction, induce a long-latency stall. */
16 __asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy));
17#endif
18
19 /*
20 * Reduce instruction retirement.
21 * This assumes the PC changes.
22 */
23 ALT_RISCV_PAUSE();
24 barrier();
25}
26
27#endif /* __ASSEMBLER__ */
28
29#endif /* __ASM_VDSO_PROCESSOR_H */