xref: /aosp_15_r20/trusty/kernel/lib/syscall/arch/arm64/syscall.S (revision 344aa361028b423587d4ef3fa52a23d194628137)
1*344aa361SAndroid Build Coastguard Worker/*
2*344aa361SAndroid Build Coastguard Worker * Copyright (c) 2014, Google, Inc. All rights reserved
3*344aa361SAndroid Build Coastguard Worker *
4*344aa361SAndroid Build Coastguard Worker * Permission is hereby granted, free of charge, to any person obtaining
5*344aa361SAndroid Build Coastguard Worker * a copy of this software and associated documentation files
6*344aa361SAndroid Build Coastguard Worker * (the "Software"), to deal in the Software without restriction,
7*344aa361SAndroid Build Coastguard Worker * including without limitation the rights to use, copy, modify, merge,
8*344aa361SAndroid Build Coastguard Worker * publish, distribute, sublicense, and/or sell copies of the Software,
9*344aa361SAndroid Build Coastguard Worker * and to permit persons to whom the Software is furnished to do so,
10*344aa361SAndroid Build Coastguard Worker * subject to the following conditions:
11*344aa361SAndroid Build Coastguard Worker *
12*344aa361SAndroid Build Coastguard Worker * The above copyright notice and this permission notice shall be
13*344aa361SAndroid Build Coastguard Worker * included in all copies or substantial portions of the Software.
14*344aa361SAndroid Build Coastguard Worker *
15*344aa361SAndroid Build Coastguard Worker * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16*344aa361SAndroid Build Coastguard Worker * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17*344aa361SAndroid Build Coastguard Worker * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18*344aa361SAndroid Build Coastguard Worker * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
19*344aa361SAndroid Build Coastguard Worker * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
20*344aa361SAndroid Build Coastguard Worker * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
21*344aa361SAndroid Build Coastguard Worker * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22*344aa361SAndroid Build Coastguard Worker */
23*344aa361SAndroid Build Coastguard Worker
24*344aa361SAndroid Build Coastguard Worker#include <arch/asm_macros.h>
25*344aa361SAndroid Build Coastguard Worker#include <asm.h>
26*344aa361SAndroid Build Coastguard Worker
27*344aa361SAndroid Build Coastguard Worker#define DAIF_MASK_IAF 0x7
28*344aa361SAndroid Build Coastguard Worker
29*344aa361SAndroid Build Coastguard Worker/* ARM syscall ABI
30*344aa361SAndroid Build Coastguard Worker * ===============
31*344aa361SAndroid Build Coastguard Worker * Only syscalls with 4 args (max) are currently supported
32*344aa361SAndroid Build Coastguard Worker * r0-r3/x0-x3 = args
33*344aa361SAndroid Build Coastguard Worker * r0-r1/x0    = return value (r0 only if 32-bit retval)
34*344aa361SAndroid Build Coastguard Worker * r12/x12     = syscall number, expected to be trashed.
35*344aa361SAndroid Build Coastguard Worker * syscalls run with interrupts enabled
36*344aa361SAndroid Build Coastguard Worker */
37*344aa361SAndroid Build Coastguard WorkerFUNCTION (arm64_syscall)
38*344aa361SAndroid Build Coastguard Worker	push	x0, x30
39*344aa361SAndroid Build Coastguard Worker	ldr	w12, [x0, #(12 << 3)]
40*344aa361SAndroid Build Coastguard Worker
41*344aa361SAndroid Build Coastguard Worker	msr	daifclr, #DAIF_MASK_IAF
42*344aa361SAndroid Build Coastguard Worker
43*344aa361SAndroid Build Coastguard Worker	adrl	x14, nr_syscalls
44*344aa361SAndroid Build Coastguard Worker	ldr	x14, [x14]
45*344aa361SAndroid Build Coastguard Worker	cmp	x12, x14
46*344aa361SAndroid Build Coastguard Worker	b.hs	.Lundefined
47*344aa361SAndroid Build Coastguard Worker	adrl	x14, syscall_table
48*344aa361SAndroid Build Coastguard Worker	ldr	x14, [x14, x12, lsl#3]
49*344aa361SAndroid Build Coastguard Worker	cbnz	x14, .Ldefined
50*344aa361SAndroid Build Coastguard Worker.Lundefined:
51*344aa361SAndroid Build Coastguard Worker	adrl	x14, sys_undefined
52*344aa361SAndroid Build Coastguard Worker.Ldefined:
53*344aa361SAndroid Build Coastguard Worker	ldp	x2, x3, [x0, #16]
54*344aa361SAndroid Build Coastguard Worker	ldp	x0, x1, [x0]
55*344aa361SAndroid Build Coastguard Worker	blr	x14
56*344aa361SAndroid Build Coastguard Worker
57*344aa361SAndroid Build Coastguard Worker	msr	daifset, #DAIF_MASK_IAF
58*344aa361SAndroid Build Coastguard Worker
59*344aa361SAndroid Build Coastguard Worker	pop	x1, x30
60*344aa361SAndroid Build Coastguard Worker
61*344aa361SAndroid Build Coastguard Worker	str	x0, [x1, 0]
62*344aa361SAndroid Build Coastguard Worker
63*344aa361SAndroid Build Coastguard Worker	ret
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