arm-trusted-firmware/include/cm_macros.S

116 lines
3.8 KiB
ArmAsm

/*
* Copyright (c) 2013-2014, 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.
*/
/* ---------------------------------------------
* Zero out the callee saved register to prevent
* leakage of secure state into the normal world
* during the first ERET after a cold/warm boot.
* ---------------------------------------------
*/
.macro zero_callee_saved_regs
mov x19, xzr
mov x20, xzr
mov x21, xzr
mov x22, xzr
mov x23, xzr
mov x24, xzr
mov x25, xzr
mov x26, xzr
mov x27, xzr
mov x28, xzr
mov x29, xzr
.endm
.macro switch_to_exception_stack reg1 reg2
mov \reg1 , sp
ldr \reg2, [\reg1, #CTX_EL3STATE_OFFSET + CTX_EXCEPTION_SP]
mov sp, \reg2
.endm
/* -----------------------------------------------------
* Handle SMC exceptions seperately from other sync.
* exceptions.
* -----------------------------------------------------
*/
.macro handle_sync_exception
stp x30, xzr, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
mrs x30, esr_el3
ubfx x30, x30, #ESR_EC_SHIFT, #ESR_EC_LENGTH
cmp x30, #EC_AARCH32_SMC
b.eq smc_handler32
cmp x30, #EC_AARCH64_SMC
b.eq smc_handler64
/* -----------------------------------------------------
* The following code handles any synchronous exception
* that is not an SMC. SP_EL3 is pointing to a context
* structure where all the scratch registers are saved.
* An exception stack is also retrieved from the context
* Currently, a register dump is printed since BL31 does
* not expect any such exceptions.
* -----------------------------------------------------
*/
bl save_scratch_registers
switch_to_exception_stack x0 x1
/* Save the core_context pointer for handled faults */
stp x0, xzr, [sp, #-0x10]!
bl fault_handler
ldp x0, xzr, [sp], #0x10
mov sp, x0
bl restore_scratch_registers
ldp x30, xzr, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
eret
.endm
/* -----------------------------------------------------
* Use a platform defined mechanism to report an async.
* exception.
* -----------------------------------------------------
*/
.macro handle_async_exception type
stp x30, xzr, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
bl save_scratch_registers
switch_to_exception_stack x0 x1
/* Save the core_context pointer */
stp x0, xzr, [sp, #-0x10]!
mov x0, \type
bl plat_report_exception
ldp x0, xzr, [sp], #0x10
mov sp, x0
bl restore_scratch_registers
ldp x30, xzr, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
.endm