1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Arm v8 Self-Hosted trace support.
4 *
5 * Copyright (C) 2021 ARM Ltd.
6 */
7
8#ifndef __CORESIGHT_SELF_HOSTED_TRACE_H
9#define __CORESIGHT_SELF_HOSTED_TRACE_H
10
11#include <asm/sysreg.h>
12
13static inline u64 read_trfcr(void)
14{
15	return read_sysreg_s(SYS_TRFCR_EL1);
16}
17
18static inline void write_trfcr(u64 val)
19{
20	write_sysreg_s(val, SYS_TRFCR_EL1);
21	isb();
22}
23
24static inline u64 cpu_prohibit_trace(void)
25{
26	u64 trfcr = read_trfcr();
27
28	/* Prohibit tracing at EL0 & the kernel EL */
29	write_trfcr(trfcr & ~(TRFCR_ELx_ExTRE | TRFCR_ELx_E0TRE));
30	/* Return the original value of the TRFCR */
31	return trfcr;
32}
33#endif /*  __CORESIGHT_SELF_HOSTED_TRACE_H */
34