bl1/aarch64/bl1_exceptions.S

/*
 * Copyright (c) 2013-2015, ARM Limited and Contributors. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of ARM nor the names of its contributors may be used
 * to endorse or promote products derived from this software without specific
 * prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <arch.h>
#include <asm_macros.S>
#include <bl_common.h>
#include <context.h>

	.globl	bl1_exceptions

	.section	.vectors, "ax"; .align 11

	/* -----------------------------------------------------
	 * Very simple stackless exception handlers used by BL1.
	 * -----------------------------------------------------
	 */
	.align	7
bl1_exceptions:
	/* -----------------------------------------------------
	 * Current EL with SP0 : 0x0 - 0x200
	 * -----------------------------------------------------
	 */
SynchronousExceptionSP0:
	mov	x0, #SYNC_EXCEPTION_SP_EL0
	bl	plat_report_exception
	b	SynchronousExceptionSP0
	check_vector_size SynchronousExceptionSP0

	.align	7
IrqSP0:
	mov	x0, #IRQ_SP_EL0
	bl	plat_report_exception
	b	IrqSP0
	check_vector_size IrqSP0

	.align	7
FiqSP0:
	mov	x0, #FIQ_SP_EL0
	bl	plat_report_exception
	b	FiqSP0
	check_vector_size FiqSP0

	.align	7
SErrorSP0:
	mov	x0, #SERROR_SP_EL0
	bl	plat_report_exception
	b	SErrorSP0
	check_vector_size SErrorSP0

	/* -----------------------------------------------------
	 * Current EL with SPx: 0x200 - 0x400
	 * -----------------------------------------------------
	 */
	.align	7
SynchronousExceptionSPx:
	mov	x0, #SYNC_EXCEPTION_SP_ELX
	bl	plat_report_exception
	b	SynchronousExceptionSPx
	check_vector_size SynchronousExceptionSPx

	.align	7
IrqSPx:
	mov	x0, #IRQ_SP_ELX
	bl	plat_report_exception
	b	IrqSPx
	check_vector_size IrqSPx

	.align	7
FiqSPx:
	mov	x0, #FIQ_SP_ELX
	bl	plat_report_exception
	b	FiqSPx
	check_vector_size FiqSPx

	.align	7
SErrorSPx:
	mov	x0, #SERROR_SP_ELX
	bl	plat_report_exception
	b	SErrorSPx
	check_vector_size SErrorSPx

	/* -----------------------------------------------------
	 * Lower EL using AArch64 : 0x400 - 0x600
	 * -----------------------------------------------------
	 */
	.align	7
SynchronousExceptionA64:
	/* Enable the SError interrupt */
	msr	daifclr, #DAIF_ABT_BIT

	str	x30, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]

	/* Expect only SMC exceptions */
	mrs	x30, esr_el3
	ubfx	x30, x30, #ESR_EC_SHIFT, #ESR_EC_LENGTH
	cmp	x30, #EC_AARCH64_SMC
	b.ne	unexpected_sync_exception

	b	smc_handler64
	check_vector_size SynchronousExceptionA64

	.align	7
IrqA64:
	mov	x0, #IRQ_AARCH64
	bl	plat_report_exception
	b	IrqA64
	check_vector_size IrqA64

	.align	7
FiqA64:
	mov	x0, #FIQ_AARCH64
	bl	plat_report_exception
	b	FiqA64
	check_vector_size FiqA64

	.align	7
SErrorA64:
	mov	x0, #SERROR_AARCH64
	bl	plat_report_exception
	b   	SErrorA64
	check_vector_size SErrorA64

	/* -----------------------------------------------------
	 * Lower EL using AArch32 : 0x600 - 0x800
	 * -----------------------------------------------------
	 */
	.align	7
SynchronousExceptionA32:
	mov	x0, #SYNC_EXCEPTION_AARCH32
	bl	plat_report_exception
	b	SynchronousExceptionA32
	check_vector_size SynchronousExceptionA32

	.align	7
IrqA32:
	mov	x0, #IRQ_AARCH32
	bl	plat_report_exception
	b	IrqA32
	check_vector_size IrqA32

	.align	7
FiqA32:
	mov	x0, #FIQ_AARCH32
	bl	plat_report_exception
	b	FiqA32
	check_vector_size FiqA32

	.align	7
SErrorA32:
	mov	x0, #SERROR_AARCH32
	bl	plat_report_exception
	b	SErrorA32
	check_vector_size SErrorA32


func smc_handler64
	/* ----------------------------------------------
	 * Switch back to SP_EL0 for the C runtime stack.
	 * ----------------------------------------------
	 */
	ldr	x30, [sp, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP]
	msr	spsel, #0
	mov	sp, x30

	/* ---------------------------------------------------------------------
	 * Only a single SMC exception from BL2 to ask BL1 to pass EL3 control
	 * to BL31 is expected here. It expects:
	 *   - X0 with RUN_IMAGE SMC function ID;
	 *   - X1 with the address of a entry_point_info_t structure describing
	 *     the BL31 entrypoint.
	 * ---------------------------------------------------------------------
	 */
	mov	x19, x0
	mov	x20, x1

	mov	x0, #RUN_IMAGE
	cmp	x19, x0
	b.ne	unexpected_sync_exception

	mov	x0, x20
	bl	bl1_print_bl31_ep_info

	ldp	x0, x1, [x20, #ENTRY_POINT_INFO_PC_OFFSET]
	msr	elr_el3, x0
	msr	spsr_el3, x1
	ubfx	x0, x1, #MODE_EL_SHIFT, #2
	cmp	x0, #MODE_EL3
	b.ne	unexpected_sync_exception

	bl	disable_mmu_icache_el3
	tlbi	alle3

#if SPIN_ON_BL1_EXIT
	bl	print_debug_loop_message
debug_loop:
	b	debug_loop
#endif

	mov	x0, x20
	bl	bl1_plat_prepare_exit

	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 smc_handler64

unexpected_sync_exception:
	mov	x0, #SYNC_EXCEPTION_AARCH64
	bl	plat_report_exception
	wfi
	b	unexpected_sync_exception