arch_features.h

/*
 * 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_apa_api_present(void)
{
	uint64_t mask = (ID_AA64ISAR1_API_MASK << ID_AA64ISAR1_API_SHIFT) |
			(ID_AA64ISAR1_APA_MASK << ID_AA64ISAR1_APA_SHIFT);

	return (read_id_aa64isar1_el1() & 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;
}

static inline bool is_armv8_5_bti_present(void)
{
	return ((read_id_aa64pfr1_el1() >> ID_AA64PFR1_EL1_BT_SHIFT) &
		ID_AA64PFR1_EL1_BT_MASK) == BTI_IMPLEMENTED;
}

#endif /* ARCH_FEATURES_H */