processor.h

 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 */