arm-trusted-firmware/common/aarch64/early_exceptions.S
Jeenu Viswambharan a806dad58c Define and use no_ret macro where no return is expected
There are many instances in ARM Trusted Firmware where control is
transferred to functions from which return isn't expected. Such jumps
are made using 'bl' instruction to provide the callee with the location
from which it was jumped to. Additionally, debuggers infer the caller by
examining where 'lr' register points to. If a 'bl' of the nature
described above falls at the end of an assembly function, 'lr' will be
left pointing to a location outside of the function range. This misleads
the debugger back trace.

This patch defines a 'no_ret' macro to be used when jumping to functions
from which return isn't expected. The macro ensures to use 'bl'
instruction for the jump, and also, for debug builds, places a 'nop'
instruction immediately thereafter (unless instructed otherwise) so as
to leave 'lr' pointing within the function range.

Change-Id: Ib34c69fc09197cfd57bc06e147cc8252910e01b0
Co-authored-by: Douglas Raillard <douglas.raillard@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
2016-12-05 14:55:35 +00:00

153 lines
4.7 KiB
ArmAsm

/*
* Copyright (c) 2013-2016, 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
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*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* 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 <asm_macros.S>
#include <bl_common.h>
/* -----------------------------------------------------------------------------
* Very simple stackless exception handlers used by BL2 and BL31 stages.
* BL31 uses them before stacks are setup. BL2 uses them throughout.
* -----------------------------------------------------------------------------
*/
.globl early_exceptions
vector_base early_exceptions
/* -----------------------------------------------------
* Current EL with SP0 : 0x0 - 0x200
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionSP0
mov x0, #SYNC_EXCEPTION_SP_EL0
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size SynchronousExceptionSP0
vector_entry IrqSP0
mov x0, #IRQ_SP_EL0
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size IrqSP0
vector_entry FiqSP0
mov x0, #FIQ_SP_EL0
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size FiqSP0
vector_entry SErrorSP0
mov x0, #SERROR_SP_EL0
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size SErrorSP0
/* -----------------------------------------------------
* Current EL with SPx: 0x200 - 0x400
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionSPx
mov x0, #SYNC_EXCEPTION_SP_ELX
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size SynchronousExceptionSPx
vector_entry IrqSPx
mov x0, #IRQ_SP_ELX
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size IrqSPx
vector_entry FiqSPx
mov x0, #FIQ_SP_ELX
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size FiqSPx
vector_entry SErrorSPx
mov x0, #SERROR_SP_ELX
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size SErrorSPx
/* -----------------------------------------------------
* Lower EL using AArch64 : 0x400 - 0x600
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionA64
mov x0, #SYNC_EXCEPTION_AARCH64
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size SynchronousExceptionA64
vector_entry IrqA64
mov x0, #IRQ_AARCH64
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size IrqA64
vector_entry FiqA64
mov x0, #FIQ_AARCH64
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size FiqA64
vector_entry SErrorA64
mov x0, #SERROR_AARCH64
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size SErrorA64
/* -----------------------------------------------------
* Lower EL using AArch32 : 0x600 - 0x800
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionA32
mov x0, #SYNC_EXCEPTION_AARCH32
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size SynchronousExceptionA32
vector_entry IrqA32
mov x0, #IRQ_AARCH32
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size IrqA32
vector_entry FiqA32
mov x0, #FIQ_AARCH32
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size FiqA32
vector_entry SErrorA32
mov x0, #SERROR_AARCH32
bl plat_report_exception
no_ret plat_panic_handler
check_vector_size SErrorA32