xref: /arm-trusted-firmware/lib/extensions/brbe/brbe.c (revision 91f16700b400a8c0651d24a598fc48ee2997a0d7)
1*91f16700Schasinglulu /*
2*91f16700Schasinglulu  * Copyright (c) 2022-2023, Arm Limited. All rights reserved.
3*91f16700Schasinglulu  *
4*91f16700Schasinglulu  * SPDX-License-Identifier: BSD-3-Clause
5*91f16700Schasinglulu  */
6*91f16700Schasinglulu 
7*91f16700Schasinglulu #include <arch.h>
8*91f16700Schasinglulu #include <arch_features.h>
9*91f16700Schasinglulu #include <arch_helpers.h>
10*91f16700Schasinglulu #include <lib/extensions/brbe.h>
11*91f16700Schasinglulu 
12*91f16700Schasinglulu void brbe_init_el3(void)
13*91f16700Schasinglulu {
14*91f16700Schasinglulu 	uint64_t val;
15*91f16700Schasinglulu 
16*91f16700Schasinglulu 	/*
17*91f16700Schasinglulu 	 * MDCR_EL3.SBRBE = 0b01
18*91f16700Schasinglulu 	 *
19*91f16700Schasinglulu 	 * Allows BRBE usage in non-secure world and prohibited in
20*91f16700Schasinglulu 	 * secure world.
21*91f16700Schasinglulu 	 */
22*91f16700Schasinglulu 	val = read_mdcr_el3();
23*91f16700Schasinglulu 	val &= ~(MDCR_SBRBE_MASK << MDCR_SBRBE_SHIFT);
24*91f16700Schasinglulu 	val |= (0x1UL << MDCR_SBRBE_SHIFT);
25*91f16700Schasinglulu 	write_mdcr_el3(val);
26*91f16700Schasinglulu }
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