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| //
| // Copyright (c) 2016 - 2020, ARM Limited. All rights reserved.
| //
| // SPDX-License-Identifier: BSD-2-Clause-Patent
| //
| //
|
|
| INCLUDE AsmMacroExport.inc
|
| RVCT_ASM_EXPORT ArmCallSvc
| // r0 will be popped just after the SVC call
| push {r0, r4-r8}
|
| // Load the SVC arguments values into the appropriate registers
| ldm r0, {r0-r7}
|
| svc #0
| // Prevent speculative execution beyond svc instruction
| dsb nsh
| isb
|
| // Load the ARM_SVC_ARGS structure address from the stack into r8
| ldr r8, [sp]
|
| // Load the SVC returned values into the appropriate registers
| // A SVC call can return up to 4 values - we do not need to store back r4-r7.
| stm r8, {r0-r3}
|
| mov r0, r8
|
| // Restore the registers r4-r8
| pop {r1, r4-r8}
| bx lr
|
| END
|
|
