• Antonio Nino Diaz's avatar
    Add support for pointer authentication · b86048c4
    Antonio Nino Diaz authored
    
    The previous commit added the infrastructure to load and save
    ARMv8.3-PAuth registers during Non-secure <-> Secure world switches, but
    didn't actually enable pointer authentication in the firmware.
    
    This patch adds the functionality needed for platforms to provide
    authentication keys for the firmware, and a new option (ENABLE_PAUTH) to
    enable pointer authentication in the firmware itself. This option is
    disabled by default, and it requires CTX_INCLUDE_PAUTH_REGS to be
    enabled.
    
    Change-Id: I35127ec271e1198d43209044de39fa712ef202a5
    Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
    b86048c4
arch_features.h 1.21 KB
/*
 * Copyright (c) 2019, Arm Limited. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#ifndef ARCH_FEATURES_H
#define ARCH_FEATURES_H

#include <stdbool.h>

#include <arch_helpers.h>

static inline bool is_armv7_gentimer_present(void)
{
	/* The Generic Timer is always present in an ARMv8-A implementation */
	return true;
}

static inline bool is_armv8_2_ttcnp_present(void)
{
	return ((read_id_aa64mmfr2_el1() >> ID_AA64MMFR2_EL1_CNP_SHIFT) &
		ID_AA64MMFR2_EL1_CNP_MASK) != 0U;
}

static inline bool is_armv8_3_pauth_present(void)
{
	uint64_t mask = (ID_AA64ISAR1_GPI_MASK << ID_AA64ISAR1_GPI_SHIFT) |
			(ID_AA64ISAR1_GPA_MASK << ID_AA64ISAR1_GPA_SHIFT) |
			(ID_AA64ISAR1_API_MASK << ID_AA64ISAR1_API_SHIFT) |
			(ID_AA64ISAR1_APA_MASK << ID_AA64ISAR1_APA_SHIFT);

	/* If any of the fields is not zero, PAuth is present */
	return (read_id_aa64isar1_el1() & mask) != 0U;
}

static inline bool is_armv8_3_pauth_api_present(void)
{
	return ((read_id_aa64isar1_el1() >> ID_AA64ISAR1_API_SHIFT) &
		ID_AA64ISAR1_API_MASK) != 0U;
}

static inline bool is_armv8_4_ttst_present(void)
{
	return ((read_id_aa64mmfr2_el1() >> ID_AA64MMFR2_EL1_ST_SHIFT) &
		ID_AA64MMFR2_EL1_ST_MASK) == 1U;
}

#endif /* ARCH_FEATURES_H */