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
87
88
89
90
91
92
93
94
95
96
97
98
99
|
/*
* SPDX-License-Identifier: GPL-2.0-or-later
* Host specific cpu identification for x86.
*/
#include "qemu/osdep.h"
#include "host/cpuinfo.h"
#ifdef CONFIG_CPUID_H
# include "qemu/cpuid.h"
#endif
unsigned cpuinfo;
/* Called both as constructor and (possibly) via other constructors. */
unsigned __attribute__((constructor)) cpuinfo_init(void)
{
unsigned info = cpuinfo;
if (info) {
return info;
}
#ifdef CONFIG_CPUID_H
unsigned max, a, b, c, d, b7 = 0, c7 = 0;
max = __get_cpuid_max(0, 0);
if (max >= 7) {
__cpuid_count(7, 0, a, b7, c7, d);
info |= (b7 & bit_BMI ? CPUINFO_BMI1 : 0);
info |= (b7 & bit_BMI2 ? CPUINFO_BMI2 : 0);
}
if (max >= 1) {
__cpuid(1, a, b, c, d);
info |= (c & bit_MOVBE ? CPUINFO_MOVBE : 0);
info |= (c & bit_PCLMUL ? CPUINFO_PCLMUL : 0);
/* NOTE: our AES support requires SSSE3 (PSHUFB) as well. */
info |= (c & bit_AES) ? CPUINFO_AES : 0;
/* For AVX features, we must check available and usable. */
if ((c & bit_AVX) && (c & bit_OSXSAVE)) {
unsigned bv = xgetbv_low(0);
if ((bv & 6) == 6) {
info |= CPUINFO_AVX1;
info |= (b7 & bit_AVX2 ? CPUINFO_AVX2 : 0);
if ((bv & 0xe0) == 0xe0) {
info |= (b7 & bit_AVX512F ? CPUINFO_AVX512F : 0);
info |= (b7 & bit_AVX512VL ? CPUINFO_AVX512VL : 0);
info |= (b7 & bit_AVX512BW ? CPUINFO_AVX512BW : 0);
info |= (b7 & bit_AVX512DQ ? CPUINFO_AVX512DQ : 0);
info |= (c7 & bit_AVX512VBMI2 ? CPUINFO_AVX512VBMI2 : 0);
}
/*
* The Intel SDM has added:
* Processors that enumerate support for Intel® AVX
* (by setting the feature flag CPUID.01H:ECX.AVX[bit 28])
* guarantee that the 16-byte memory operations performed
* by the following instructions will always be carried
* out atomically:
* - MOVAPD, MOVAPS, and MOVDQA.
* - VMOVAPD, VMOVAPS, and VMOVDQA when encoded with VEX.128.
* - VMOVAPD, VMOVAPS, VMOVDQA32, and VMOVDQA64 when encoded
* with EVEX.128 and k0 (masking disabled).
* Note that these instructions require the linear addresses
* of their memory operands to be 16-byte aligned.
*
* AMD has provided an even stronger guarantee that processors
* with AVX provide 16-byte atomicity for all cacheable,
* naturally aligned single loads and stores, e.g. MOVDQU.
*
* See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104688
*/
__cpuid(0, a, b, c, d);
if (c == signature_INTEL_ecx) {
info |= CPUINFO_ATOMIC_VMOVDQA;
} else if (c == signature_AMD_ecx) {
info |= CPUINFO_ATOMIC_VMOVDQA | CPUINFO_ATOMIC_VMOVDQU;
}
}
}
}
max = __get_cpuid_max(0x8000000, 0);
if (max >= 1) {
__cpuid(0x80000001, a, b, c, d);
info |= (c & bit_LZCNT ? CPUINFO_LZCNT : 0);
}
#endif
info |= CPUINFO_ALWAYS;
cpuinfo = info;
return info;
}
|
