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/*
* Copyright (c) 2019, Arm Limited. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <arch.h>
#include <asm_macros.S>
#include <lib/el3_runtime/cpu_data.h>
.global pauth_init_enable_el1
.global pauth_disable_el1
.global pauth_init_enable_el3
.global pauth_disable_el3
.globl pauth_load_bl31_apiakey
/* -------------------------------------------------------------
* Program APIAKey_EL1 and enable pointer authentication in EL1
* -------------------------------------------------------------
*/
func pauth_init_enable_el1
stp x29, x30, [sp, #-16]!
/* Initialize platform key */
bl plat_init_apkey
/* Program instruction key A used by the Trusted Firmware */
msr APIAKeyLo_EL1, x0
msr APIAKeyHi_EL1, x1
/* Enable pointer authentication */
mrs x0, sctlr_el1
orr x0, x0, #SCTLR_EnIA_BIT
#if ENABLE_BTI
/* Enable PAC branch type compatibility */
bic x0, x0, #(SCTLR_BT0_BIT | SCTLR_BT1_BIT)
#endif
msr sctlr_el1, x0
isb
ldp x29, x30, [sp], #16
ret
endfunc pauth_init_enable_el1
/* -------------------------------------------------------------
* Disable pointer authentication in EL3
* -------------------------------------------------------------
*/
func pauth_disable_el1
mrs x0, sctlr_el1
bic x0, x0, #SCTLR_EnIA_BIT
msr sctlr_el1, x0
isb
ret
endfunc pauth_disable_el1
/* -------------------------------------------------------------
* Program APIAKey_EL1 and enable pointer authentication in EL3
* -------------------------------------------------------------
*/
func pauth_init_enable_el3
stp x29, x30, [sp, #-16]!
/* Initialize platform key */
bl plat_init_apkey
/* Program instruction key A used by the Trusted Firmware */
msr APIAKeyLo_EL1, x0
msr APIAKeyHi_EL1, x1
/* Enable pointer authentication */
mrs x0, sctlr_el3
orr x0, x0, #SCTLR_EnIA_BIT
#if ENABLE_BTI
/* Enable PAC branch type compatibility */
bic x0, x0, #SCTLR_BT_BIT
#endif
msr sctlr_el3, x0
isb
ldp x29, x30, [sp], #16
ret
endfunc pauth_init_enable_el3
/* -------------------------------------------------------------
* Disable pointer authentication in EL3
* -------------------------------------------------------------
*/
func pauth_disable_el3
mrs x0, sctlr_el3
bic x0, x0, #SCTLR_EnIA_BIT
msr sctlr_el3, x0
isb
ret
endfunc pauth_disable_el3
/* -------------------------------------------------------------
* The following function strictly follows the AArch64 PCS
* to use x9-x17 (temporary caller-saved registers) to load
* the APIAKey_EL1 used by the firmware.
* -------------------------------------------------------------
*/
func pauth_load_bl31_apiakey
/* tpidr_el3 contains the address of cpu_data structure */
mrs x9, tpidr_el3
/* Load apiakey from cpu_data */
ldp x10, x11, [x9, #CPU_DATA_APIAKEY_OFFSET]
/* Program instruction key A */
msr APIAKeyLo_EL1, x10
msr APIAKeyHi_EL1, x11
isb
ret
endfunc pauth_load_bl31_apiakey