xref: /rk3399_ARM-atf/lib/extensions/trf/aarch64/trf.c (revision 4c7fa977b7aa300fdeaee7157c241163709c860e)
18fcd3d96SManish V Badarkhe /*
2*c1b0a97bSBoyan Karatotev  * Copyright (c) 2021-2025, 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 
trf_enable(cpu_context_t * ctx)12123002f9SJayanth Dodderi Chidanand void trf_enable(cpu_context_t *ctx)
138fcd3d96SManish V Badarkhe {
14123002f9SJayanth Dodderi Chidanand 	el3_state_t *state = get_el3state_ctx(ctx);
15123002f9SJayanth Dodderi Chidanand 	u_register_t mdcr_el3_val = read_ctx_reg(state, CTX_MDCR_EL3);
168fcd3d96SManish V Badarkhe 
178fcd3d96SManish V Badarkhe 	/*
1899506facSBoyan Karatotev 	 * MDCR_EL3.STE = b0
1999506facSBoyan Karatotev 	 * Trace prohibited in Secure state unless overridden by the
2099506facSBoyan Karatotev 	 * IMPLEMENTATION DEFINED authentication interface.
2199506facSBoyan Karatotev 	 *
228fcd3d96SManish V Badarkhe 	 * MDCR_EL3.TTRF = b0
238fcd3d96SManish V Badarkhe 	 * Allow access of trace filter control registers from NS-EL2
248fcd3d96SManish V Badarkhe 	 * and NS-EL1 when NS-EL2 is implemented but not used
25*c1b0a97bSBoyan Karatotev 	 *
26*c1b0a97bSBoyan Karatotev 	 * MDCR_EL3.RLTE = b0
27*c1b0a97bSBoyan Karatotev 	 * Trace prohibited in Realm state, unless overridden by the
28*c1b0a97bSBoyan Karatotev 	 * IMPLEMENTATION DEFINED authentication interface.
298fcd3d96SManish V Badarkhe 	 */
30*c1b0a97bSBoyan Karatotev 	mdcr_el3_val &= ~(MDCR_STE_BIT | MDCR_TTRF_BIT | MDCR_RLTE_BIT);
31123002f9SJayanth Dodderi Chidanand 	write_ctx_reg(state, CTX_MDCR_EL3, mdcr_el3_val);
328fcd3d96SManish V Badarkhe }
3360d330dcSBoyan Karatotev 
trf_init_el2_unused(void)3460d330dcSBoyan Karatotev void trf_init_el2_unused(void)
3560d330dcSBoyan Karatotev {
3660d330dcSBoyan Karatotev 	/*
3760d330dcSBoyan Karatotev 	 * MDCR_EL2.TTRF: Set to zero so that access to Trace
3860d330dcSBoyan Karatotev 	 *  Filter Control register TRFCR_EL1 at EL1 is not
3960d330dcSBoyan Karatotev 	 *  trapped to EL2. This bit is RES0 in versions of
4060d330dcSBoyan Karatotev 	 *  the architecture earlier than ARMv8.4.
4160d330dcSBoyan Karatotev 	 *
4260d330dcSBoyan Karatotev 	 */
4360d330dcSBoyan Karatotev 	write_mdcr_el2(read_mdcr_el2() & ~MDCR_EL2_TTRF);
4460d330dcSBoyan Karatotev }
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