• Antonio Nino Diaz's avatar
    BL2_AT_EL3: Enable pointer authentication support · dcbfa11b
    Antonio Nino Diaz authored
    
    The size increase after enabling options related to ARMv8.3-PAuth is:
    
    +----------------------------+-------+-------+-------+--------+
    |                            |  text |  bss  |  data | rodata |
    +----------------------------+-------+-------+-------+--------+
    | CTX_INCLUDE_PAUTH_REGS = 1 |   +44 |   +0  |   +0  |   +0   |
    |                            |  0.2% |       |       |        |
    +----------------------------+-------+-------+-------+--------+
    | ENABLE_PAUTH = 1           |  +712 |   +0  |  +16  |   +0   |
    |                            |  3.1% |       |  0.9% |        |
    +----------------------------+-------+-------+-------+--------+
    
    The results are valid for the following build configuration:
    
        make PLAT=fvp SPD=tspd DEBUG=1 \
        BL2_AT_EL3=1                   \
        CTX_INCLUDE_PAUTH_REGS=1       \
        ENABLE_PAUTH=1
    
    Change-Id: I1c0616e7dea30962a92b4fd113428bc30a018320
    Signed-off-by: default avatarAntonio Nino Diaz <antonio.ninodiaz@arm.com>
    dcbfa11b
bl2_el3_entrypoint.S 2.81 KB
/*
 * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <arch.h>
#include <asm_macros.S>
#include <common/bl_common.h>
#include <el3_common_macros.S>

	.globl	bl2_entrypoint
	.globl	bl2_vector_table
	.globl	bl2_el3_run_image
	.globl	bl2_run_next_image

func bl2_entrypoint
	/* Save arguments x0-x3 from previous Boot loader */
	mov	x20, x0
	mov	x21, x1
	mov	x22, x2
	mov	x23, x3

	el3_entrypoint_common                                   \
		_init_sctlr=1                                   \
		_warm_boot_mailbox=!PROGRAMMABLE_RESET_ADDRESS  \
		_secondary_cold_boot=!COLD_BOOT_SINGLE_CPU      \
		_init_memory=1                                  \
		_init_c_runtime=1                               \
		_exception_vectors=bl2_el3_exceptions

	/* ---------------------------------------------
	 * Restore parameters of boot rom
	 * ---------------------------------------------
	 */
	mov	x0, x20
	mov	x1, x21
	mov	x2, x22
	mov	x3, x23

	/* ---------------------------------------------
	 * Perform BL2 setup
	 * ---------------------------------------------
	 */
	bl	bl2_el3_setup

	/* ---------------------------------------------
	 * Enable pointer authentication
	 * ---------------------------------------------
	 */
#if ENABLE_PAUTH
	mrs	x0, sctlr_el3
	orr	x0, x0, #SCTLR_EnIA_BIT
	msr	sctlr_el3, x0
	isb
#endif /* ENABLE_PAUTH */

	/* ---------------------------------------------
	 * Jump to main function.
	 * ---------------------------------------------
	 */
	bl	bl2_main

	/* ---------------------------------------------
	 * Should never reach this point.
	 * ---------------------------------------------
	 */
	no_ret	plat_panic_handler
endfunc bl2_entrypoint

func bl2_run_next_image
	mov	x20,x0
	/* ---------------------------------------------
	 * MMU needs to be disabled because both BL2 and BL31 execute
	 * in EL3, and therefore share the same address space.
	 * BL31 will initialize the address space according to its
	 * own requirement.
	 * ---------------------------------------------
	 */
	bl	disable_mmu_icache_el3
	tlbi	alle3
	bl	bl2_el3_plat_prepare_exit

	/* ---------------------------------------------
	 * Disable pointer authentication before jumping to BL31 or that will
	 * cause an authentication failure during the early platform init.
	 * ---------------------------------------------
	 */
#if ENABLE_PAUTH
	mrs	x0, sctlr_el3
	bic	x0, x0, #SCTLR_EnIA_BIT
	msr	sctlr_el3, x0
	isb
#endif /* ENABLE_PAUTH */

	ldp	x0, x1, [x20, #ENTRY_POINT_INFO_PC_OFFSET]
	msr	elr_el3, x0
	msr	spsr_el3, x1

	ldp	x6, x7, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x30)]
	ldp	x4, x5, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x20)]
	ldp	x2, x3, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x10)]
	ldp	x0, x1, [x20, #(ENTRY_POINT_INFO_ARGS_OFFSET + 0x0)]
	eret
endfunc bl2_run_next_image