/* * Copyright (c) 2021-2023, Arm Limited. All rights reserved. * * SPDX-License-Identifier: BSD-3-Clause */ #include #include #include #include void trf_init_el3(void) { u_register_t val; /* * MDCR_EL3.STE = b0 * Trace prohibited in Secure state unless overridden by the * IMPLEMENTATION DEFINED authentication interface. * * MDCR_EL3.TTRF = b0 * Allow access of trace filter control registers from NS-EL2 * and NS-EL1 when NS-EL2 is implemented but not used */ val = read_mdcr_el3(); val &= ~(MDCR_STE_BIT | MDCR_TTRF_BIT); write_mdcr_el3(val); } void trf_init_el2_unused(void) { /* * MDCR_EL2.TTRF: Set to zero so that access to Trace * Filter Control register TRFCR_EL1 at EL1 is not * trapped to EL2. This bit is RES0 in versions of * the architecture earlier than ARMv8.4. * */ write_mdcr_el2(read_mdcr_el2() & ~MDCR_EL2_TTRF); }