| // | |
| // Copyright (c) 2012 - 2020, ARM Limited. All rights reserved. | |
| // | |
| // SPDX-License-Identifier: BSD-2-Clause-Patent | |
| // | |
| // | |
| #include <AsmMacroIoLibV8.h> | |
| .text | |
| .align 3 | |
| ASM_FUNC(ArmCallSvc) | |
| // Push frame pointer and return address on the stack | |
| stp x29, x30, [sp, #-32]! | |
| mov x29, sp | |
| // Push x0 on the stack - The stack must always be quad-word aligned | |
| str x0, [sp, #16] | |
| // Load the SVC arguments values into the appropriate registers | |
| ldp x6, x7, [x0, #48] | |
| ldp x4, x5, [x0, #32] | |
| ldp x2, x3, [x0, #16] | |
| ldp x0, x1, [x0, #0] | |
| svc #0 | |
| // Prevent speculative execution beyond svc instruction | |
| dsb nsh | |
| isb | |
| // Pop the ARM_SVC_ARGS structure address from the stack into x9 | |
| ldr x9, [sp, #16] | |
| // Store the SVC returned values into the ARM_SVC_ARGS structure. | |
| // A SVC call can return up to 8 values | |
| stp x0, x1, [x9, #0] | |
| stp x2, x3, [x9, #16] | |
| stp x4, x5, [x9, #32] | |
| stp x6, x7, [x9, #48] | |
| mov x0, x9 | |
| ldp x29, x30, [sp], #32 | |
| ret |