1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
/*
* arch/xtensa/kernel/mcount.S
*
* Xtensa specific mcount support
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2013 Tensilica Inc.
*/
#include <linux/linkage.h>
#include <asm/asmmacro.h>
#include <asm/ftrace.h>
/*
* Entry condition:
*
* a2: a0 of the caller in windowed ABI
* a10: a0 of the caller in call0 ABI
*
* In call0 ABI the function _mcount is called with the special ABI:
* its argument is in a10 and all the usual argument registers (a2 - a7)
* must be preserved in addition to callee-saved a12 - a15.
*/
ENTRY(_mcount)
#if defined(__XTENSA_WINDOWED_ABI__)
abi_entry_default
movi a4, ftrace_trace_function
l32i a4, a4, 0
movi a3, ftrace_stub
bne a3, a4, 1f
abi_ret_default
1: xor a7, a2, a1
movi a3, 0x3fffffff
and a7, a7, a3
xor a7, a7, a1
xor a6, a0, a1
and a6, a6, a3
xor a6, a6, a1
addi a6, a6, -MCOUNT_INSN_SIZE
callx4 a4
abi_ret_default
#elif defined(__XTENSA_CALL0_ABI__)
abi_entry_default
movi a9, ftrace_trace_function
l32i a9, a9, 0
movi a11, ftrace_stub
bne a9, a11, 1f
abi_ret_default
1: abi_entry(28)
s32i a0, sp, 0
s32i a2, sp, 4
s32i a3, sp, 8
s32i a4, sp, 12
s32i a5, sp, 16
s32i a6, sp, 20
s32i a7, sp, 24
addi a2, a10, -MCOUNT_INSN_SIZE
callx0 a9
l32i a0, sp, 0
l32i a2, sp, 4
l32i a3, sp, 8
l32i a4, sp, 12
l32i a5, sp, 16
l32i a6, sp, 20
l32i a7, sp, 24
abi_ret(28)
#else
#error Unsupported Xtensa ABI
#endif
ENDPROC(_mcount)
EXPORT_SYMBOL(_mcount)
ENTRY(ftrace_stub)
abi_entry_default
abi_ret_default
ENDPROC(ftrace_stub)
|
