1 /*
2  * Copyright (c) 2018-2022, ARM Limited and Contributors. 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_features.h>
11 #include <arch_helpers.h>
12 #include <lib/extensions/mpam.h>
13 
mpam_enable(bool el2_unused)14 void mpam_enable(bool el2_unused)
15 {
16 	/* Check if MPAM is implemented */
17 	if (get_mpam_version() == 0U) {
18 		return;
19 	}
20 
21 	/*
22 	 * Enable MPAM, and disable trapping to EL3 when lower ELs access their
23 	 * own MPAM registers.
24 	 */
25 	write_mpam3_el3(MPAM3_EL3_MPAMEN_BIT);
26 
27 	/*
28 	 * If EL2 is implemented but unused, disable trapping to EL2 when lower
29 	 * ELs access their own MPAM registers.
30 	 */
31 	if (el2_unused) {
32 		write_mpam2_el2(0ULL);
33 
34 		if ((read_mpamidr_el1() & MPAMIDR_HAS_HCR_BIT) != 0U) {
35 			write_mpamhcr_el2(0ULL);
36 		}
37 	}
38 }
39