xref: /rk3399_ARM-atf/lib/extensions/trf/aarch64/trf.c (revision 99506face112410ae37cf617b6efa809b4eee0ee)
18fcd3d96SManish V Badarkhe /*
260d330dcSBoyan Karatotev  * Copyright (c) 2021-2023, Arm Limited. All rights reserved.
38fcd3d96SManish V Badarkhe  *
48fcd3d96SManish V Badarkhe  * SPDX-License-Identifier: BSD-3-Clause
58fcd3d96SManish V Badarkhe  */
68fcd3d96SManish V Badarkhe 
78fcd3d96SManish V Badarkhe #include <arch.h>
8fc8d2d39SAndre Przywara #include <arch_features.h>
98fcd3d96SManish V Badarkhe #include <arch_helpers.h>
108fcd3d96SManish V Badarkhe #include <lib/extensions/trf.h>
118fcd3d96SManish V Badarkhe 
1260d330dcSBoyan Karatotev void trf_init_el3(void)
138fcd3d96SManish V Badarkhe {
1460d330dcSBoyan Karatotev 	u_register_t val;
158fcd3d96SManish V Badarkhe 
168fcd3d96SManish V Badarkhe 	/*
17*99506facSBoyan Karatotev 	 * MDCR_EL3.STE = b0
18*99506facSBoyan Karatotev 	 * Trace prohibited in Secure state unless overridden by the
19*99506facSBoyan Karatotev 	 * IMPLEMENTATION DEFINED authentication interface.
20*99506facSBoyan Karatotev 	 *
218fcd3d96SManish V Badarkhe 	 * MDCR_EL3.TTRF = b0
228fcd3d96SManish V Badarkhe 	 * Allow access of trace filter control registers from NS-EL2
238fcd3d96SManish V Badarkhe 	 * and NS-EL1 when NS-EL2 is implemented but not used
248fcd3d96SManish V Badarkhe 	 */
258fcd3d96SManish V Badarkhe 	val = read_mdcr_el3();
26*99506facSBoyan Karatotev 	val &= ~(MDCR_STE_BIT | MDCR_TTRF_BIT);
278fcd3d96SManish V Badarkhe 	write_mdcr_el3(val);
288fcd3d96SManish V Badarkhe }
2960d330dcSBoyan Karatotev 
3060d330dcSBoyan Karatotev void trf_init_el2_unused(void)
3160d330dcSBoyan Karatotev {
3260d330dcSBoyan Karatotev 	/*
3360d330dcSBoyan Karatotev 	 * MDCR_EL2.TTRF: Set to zero so that access to Trace
3460d330dcSBoyan Karatotev 	 *  Filter Control register TRFCR_EL1 at EL1 is not
3560d330dcSBoyan Karatotev 	 *  trapped to EL2. This bit is RES0 in versions of
3660d330dcSBoyan Karatotev 	 *  the architecture earlier than ARMv8.4.
3760d330dcSBoyan Karatotev 	 *
3860d330dcSBoyan Karatotev 	 */
3960d330dcSBoyan Karatotev 	write_mdcr_el2(read_mdcr_el2() & ~MDCR_EL2_TTRF);
4060d330dcSBoyan Karatotev }
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