xref: /arm-trusted-firmware/lib/extensions/mpam/mpam.c (revision 91f16700b400a8c0651d24a598fc48ee2997a0d7)
1*91f16700Schasinglulu /*
2*91f16700Schasinglulu  * Copyright (c) 2018-2023, Arm Limited and Contributors. All rights reserved.
3*91f16700Schasinglulu  *
4*91f16700Schasinglulu  * SPDX-License-Identifier: BSD-3-Clause
5*91f16700Schasinglulu  */
6*91f16700Schasinglulu 
7*91f16700Schasinglulu #include <stdbool.h>
8*91f16700Schasinglulu 
9*91f16700Schasinglulu #include <arch.h>
10*91f16700Schasinglulu #include <arch_features.h>
11*91f16700Schasinglulu #include <arch_helpers.h>
12*91f16700Schasinglulu #include <lib/extensions/mpam.h>
13*91f16700Schasinglulu 
14*91f16700Schasinglulu void mpam_enable(cpu_context_t *context)
15*91f16700Schasinglulu {
16*91f16700Schasinglulu 	u_register_t mpam3_el3;
17*91f16700Schasinglulu 
18*91f16700Schasinglulu 	mpam3_el3 = read_ctx_reg(get_el3state_ctx(context), CTX_MPAM3_EL3);
19*91f16700Schasinglulu 
20*91f16700Schasinglulu 	/*
21*91f16700Schasinglulu 	 * Enable MPAM, and disable trapping to EL3 when lower ELs access their
22*91f16700Schasinglulu 	 * own MPAM registers
23*91f16700Schasinglulu 	 */
24*91f16700Schasinglulu 	mpam3_el3 = (mpam3_el3 | MPAM3_EL3_MPAMEN_BIT) &
25*91f16700Schasinglulu 				~(MPAM3_EL3_TRAPLOWER_BIT);
26*91f16700Schasinglulu 	write_ctx_reg(get_el3state_ctx(context), CTX_MPAM3_EL3, mpam3_el3);
27*91f16700Schasinglulu }
28*91f16700Schasinglulu 
29*91f16700Schasinglulu /*
30*91f16700Schasinglulu  * If EL2 is implemented but unused, disable trapping to EL2 when lower ELs
31*91f16700Schasinglulu  * access their own MPAM registers.
32*91f16700Schasinglulu  */
33*91f16700Schasinglulu void mpam_init_el2_unused(void)
34*91f16700Schasinglulu {
35*91f16700Schasinglulu 	write_mpam2_el2(0ULL);
36*91f16700Schasinglulu 
37*91f16700Schasinglulu 	if ((read_mpamidr_el1() & MPAMIDR_HAS_HCR_BIT) != 0U) {
38*91f16700Schasinglulu 		write_mpamhcr_el2(0ULL);
39*91f16700Schasinglulu 	}
40*91f16700Schasinglulu 
41*91f16700Schasinglulu }
42