xref: /rk3399_ARM-atf/lib/extensions/trf/aarch64/trf.c (revision 8fcd3d9600bb2cb6809c6fc68f945ce3ad89633d)
1*8fcd3d96SManish V Badarkhe /*
2*8fcd3d96SManish V Badarkhe  * Copyright (c) 2021, Arm Limited. All rights reserved.
3*8fcd3d96SManish V Badarkhe  *
4*8fcd3d96SManish V Badarkhe  * SPDX-License-Identifier: BSD-3-Clause
5*8fcd3d96SManish V Badarkhe  */
6*8fcd3d96SManish V Badarkhe 
7*8fcd3d96SManish V Badarkhe #include <stdbool.h>
8*8fcd3d96SManish V Badarkhe 
9*8fcd3d96SManish V Badarkhe #include <arch.h>
10*8fcd3d96SManish V Badarkhe #include <arch_helpers.h>
11*8fcd3d96SManish V Badarkhe #include <lib/extensions/trf.h>
12*8fcd3d96SManish V Badarkhe 
13*8fcd3d96SManish V Badarkhe static bool trf_supported(void)
14*8fcd3d96SManish V Badarkhe {
15*8fcd3d96SManish V Badarkhe 	uint64_t features;
16*8fcd3d96SManish V Badarkhe 
17*8fcd3d96SManish V Badarkhe 	features = read_id_aa64dfr0_el1() >> ID_AA64DFR0_TRACEFILT_SHIFT;
18*8fcd3d96SManish V Badarkhe 	return ((features & ID_AA64DFR0_TRACEFILT_MASK) ==
19*8fcd3d96SManish V Badarkhe 		ID_AA64DFR0_TRACEFILT_SUPPORTED);
20*8fcd3d96SManish V Badarkhe }
21*8fcd3d96SManish V Badarkhe 
22*8fcd3d96SManish V Badarkhe void trf_enable(void)
23*8fcd3d96SManish V Badarkhe {
24*8fcd3d96SManish V Badarkhe 	uint64_t val;
25*8fcd3d96SManish V Badarkhe 
26*8fcd3d96SManish V Badarkhe 	if (trf_supported()) {
27*8fcd3d96SManish V Badarkhe 		/*
28*8fcd3d96SManish V Badarkhe 		 * MDCR_EL3.TTRF = b0
29*8fcd3d96SManish V Badarkhe 		 * Allow access of trace filter control registers from NS-EL2
30*8fcd3d96SManish V Badarkhe 		 * and NS-EL1 when NS-EL2 is implemented but not used
31*8fcd3d96SManish V Badarkhe 		 */
32*8fcd3d96SManish V Badarkhe 		val = read_mdcr_el3();
33*8fcd3d96SManish V Badarkhe 		val &= ~MDCR_TTRF_BIT;
34*8fcd3d96SManish V Badarkhe 		write_mdcr_el3(val);
35*8fcd3d96SManish V Badarkhe 	}
36*8fcd3d96SManish V Badarkhe }
37