1//
2//  Copyright (c) 2012-2014, ARM Limited. All rights reserved.
3//  Copyright (c) 2014, Linaro Limited. All rights reserved.
4//
5//  This program and the accompanying materials
6//  are licensed and made available under the terms and conditions of the BSD License
7//  which accompanies this distribution.  The full text of the license may be found at
8//  http://opensource.org/licenses/bsd-license.php
9//
10//  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11//  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
12//
13//
14
15.text
16.align 3
17
18GCC_ASM_EXPORT(ArmCallHvc)
19
20ASM_PFX(ArmCallHvc):
21  // Push x0 on the stack - The stack must always be quad-word aligned
22  str   x0, [sp, #-16]!
23
24  // Load the HVC arguments values into the appropriate registers
25  ldp   x6, x7, [x0, #48]
26  ldp   x4, x5, [x0, #32]
27  ldp   x2, x3, [x0, #16]
28  ldp   x0, x1, [x0, #0]
29
30  hvc   #0
31
32  // Pop the ARM_HVC_ARGS structure address from the stack into x9
33  ldr   x9, [sp], #16
34
35  // Store the HVC returned values into the ARM_HVC_ARGS structure.
36  // A HVC call can return up to 4 values
37  stp   x2, x3, [x9, #16]
38  stp   x0, x1, [x9, #0]
39
40  mov   x0, x9
41
42  ret
43