1 /*
2  * Copyright (c) 2018-2023, 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(cpu_context_t * context)14 void mpam_enable(cpu_context_t *context)
15 {
16 	u_register_t mpam3_el3;
17 
18 	mpam3_el3 = read_ctx_reg(get_el3state_ctx(context), CTX_MPAM3_EL3);
19 
20 	/*
21 	 * Enable MPAM, and disable trapping to EL3 when lower ELs access their
22 	 * own MPAM registers
23 	 */
24 	mpam3_el3 = (mpam3_el3 | MPAM3_EL3_MPAMEN_BIT) &
25 				~(MPAM3_EL3_TRAPLOWER_BIT);
26 	write_ctx_reg(get_el3state_ctx(context), CTX_MPAM3_EL3, mpam3_el3);
27 }
28 
29 /*
30  * If EL2 is implemented but unused, disable trapping to EL2 when lower ELs
31  * access their own MPAM registers.
32  */
mpam_init_el2_unused(void)33 void mpam_init_el2_unused(void)
34 {
35 	write_mpam2_el2(0ULL);
36 
37 	if ((read_mpamidr_el1() & MPAMIDR_HAS_HCR_BIT) != 0U) {
38 		write_mpamhcr_el2(0ULL);
39 	}
40 
41 }
42