1 /*
2  * Copyright (c) 2021, Arm Limited. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <stdbool.h>
8 
9 #include <arch.h>
10 #include <arch_helpers.h>
11 #include <lib/extensions/sys_reg_trace.h>
12 
sys_reg_trace_supported(void)13 static bool sys_reg_trace_supported(void)
14 {
15 	uint32_t features;
16 
17 	features = read_id_dfr0() >> ID_DFR0_COPTRC_SHIFT;
18 	return ((features & ID_DFR0_COPTRC_MASK) ==
19 		ID_DFR0_COPTRC_SUPPORTED);
20 }
21 
sys_reg_trace_enable(void)22 void sys_reg_trace_enable(void)
23 {
24 	uint32_t val;
25 
26 	if (sys_reg_trace_supported()) {
27 		/*
28 		 * NSACR.NSTRCDIS = b0
29 		 * enable NS system register access to implemented trace
30 		 * registers.
31 		 */
32 		val = read_nsacr();
33 		val &= ~NSTRCDIS_BIT;
34 		write_nsacr(val);
35 	}
36 }
37