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/*
* 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
* 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 <bl1.h>
#include <context.h>
/* -----------------------------------------------------------------------------
* Very simple stackless exception handlers used by BL1.
* -----------------------------------------------------------------------------
*/
.globl bl1_exceptions
vector_base bl1_exceptions
/* -----------------------------------------------------
* Current EL with SP0 : 0x0 - 0x200
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionSP0
mov x0, #SYNC_EXCEPTION_SP_EL0
bl plat_report_exception
b SynchronousExceptionSP0
check_vector_size SynchronousExceptionSP0
vector_entry IrqSP0
mov x0, #IRQ_SP_EL0
bl plat_report_exception
b IrqSP0
check_vector_size IrqSP0
vector_entry FiqSP0
mov x0, #FIQ_SP_EL0
bl plat_report_exception
b FiqSP0
check_vector_size FiqSP0
vector_entry SErrorSP0
mov x0, #SERROR_SP_EL0
bl plat_report_exception
b SErrorSP0
check_vector_size SErrorSP0
/* -----------------------------------------------------
* Current EL with SPx: 0x200 - 0x400
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionSPx
mov x0, #SYNC_EXCEPTION_SP_ELX
bl plat_report_exception
b SynchronousExceptionSPx
check_vector_size SynchronousExceptionSPx
vector_entry IrqSPx
mov x0, #IRQ_SP_ELX
bl plat_report_exception
b IrqSPx
check_vector_size IrqSPx
vector_entry FiqSPx
mov x0, #FIQ_SP_ELX
bl plat_report_exception
b FiqSPx
check_vector_size FiqSPx
vector_entry SErrorSPx
mov x0, #SERROR_SP_ELX
bl plat_report_exception
b SErrorSPx
check_vector_size SErrorSPx
/* -----------------------------------------------------
* Lower EL using AArch64 : 0x400 - 0x600
* -----------------------------------------------------
*/
vector_entry 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
vector_entry IrqA64
mov x0, #IRQ_AARCH64
bl plat_report_exception
b IrqA64
check_vector_size IrqA64
vector_entry FiqA64
mov x0, #FIQ_AARCH64
bl plat_report_exception
b FiqA64
check_vector_size FiqA64
vector_entry SErrorA64
mov x0, #SERROR_AARCH64
bl plat_report_exception
b SErrorA64
check_vector_size SErrorA64
/* -----------------------------------------------------
* Lower EL using AArch32 : 0x600 - 0x800
* -----------------------------------------------------
*/
vector_entry SynchronousExceptionA32
mov x0, #SYNC_EXCEPTION_AARCH32
bl plat_report_exception
b SynchronousExceptionA32
check_vector_size SynchronousExceptionA32
vector_entry IrqA32
mov x0, #IRQ_AARCH32
bl plat_report_exception
b IrqA32
check_vector_size IrqA32
vector_entry FiqA32
mov x0, #FIQ_AARCH32
bl plat_report_exception
b FiqA32
check_vector_size FiqA32
vector_entry SErrorA32
mov x0, #SERROR_AARCH32
bl plat_report_exception
b SErrorA32
check_vector_size SErrorA32
func smc_handler64
/* ----------------------------------------------
* Detect if this is a RUN_IMAGE or other SMC.
* ----------------------------------------------
*/
mov x30, #BL1_SMC_RUN_IMAGE
cmp x30, x0
b.ne smc_handler
/* ------------------------------------------------
* Make sure only Secure world reaches here.
* ------------------------------------------------
*/
mrs x30, scr_el3
tst x30, #SCR_NS_BIT
b.ne unexpected_sync_exception
/* ----------------------------------------------
* Handling RUN_IMAGE SMC. First 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
/* ---------------------------------------------------------------------
* Pass EL3 control to BL31.
* Here it expects X1 with the address of a entry_point_info_t
* structure describing the BL31 entrypoint.
* ---------------------------------------------------------------------
*/
mov x20, x1
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
/* -----------------------------------------------------
* Save Secure/Normal world context and jump to
* BL1 SMC handler.
* -----------------------------------------------------
*/
smc_handler:
/* -----------------------------------------------------
* Save the GP registers x0-x29.
* TODO: Revisit to store only SMCC specified registers.
* -----------------------------------------------------
*/
bl save_gp_registers
/* -----------------------------------------------------
* Populate the parameters for the SMC handler. We
* already have x0-x4 in place. x5 will point to a
* cookie (not used now). x6 will point to the context
* structure (SP_EL3) and x7 will contain flags we need
* to pass to the handler.
* -----------------------------------------------------
*/
mov x5, xzr
mov x6, sp
/* -----------------------------------------------------
* Restore the saved C runtime stack value which will
* become the new SP_EL0 i.e. EL3 runtime stack. It was
* saved in the 'cpu_context' structure prior to the last
* ERET from EL3.
* -----------------------------------------------------
*/
ldr x12, [x6, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP]
/* ---------------------------------------------
* Switch back to SP_EL0 for the C runtime stack.
* ---------------------------------------------
*/
msr spsel, #0
mov sp, x12
/* -----------------------------------------------------
* Save the SPSR_EL3, ELR_EL3, & SCR_EL3 in case there
* is a world switch during SMC handling.
* -----------------------------------------------------
*/
mrs x16, spsr_el3
mrs x17, elr_el3
mrs x18, scr_el3
stp x16, x17, [x6, #CTX_EL3STATE_OFFSET + CTX_SPSR_EL3]
str x18, [x6, #CTX_EL3STATE_OFFSET + CTX_SCR_EL3]
/* Copy SCR_EL3.NS bit to the flag to indicate caller's security */
bfi x7, x18, #0, #1
/* -----------------------------------------------------
* Go to BL1 SMC handler.
* -----------------------------------------------------
*/
bl bl1_smc_handler
/* -----------------------------------------------------
* Do the transition to next BL image.
* -----------------------------------------------------
*/
b el3_exit