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Diffstat (limited to 'vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go')
-rw-r--r--vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go111
1 files changed, 0 insertions, 111 deletions
diff --git a/vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go b/vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go
deleted file mode 100644
index a968b80..0000000
--- a/vendor/golang.org/x/sys/cpu/cpu_linux_arm64.go
+++ /dev/null
@@ -1,111 +0,0 @@
1// Copyright 2018 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package cpu
6
7import (
8 "strings"
9 "syscall"
10)
11
12// HWCAP/HWCAP2 bits. These are exposed by Linux.
13const (
14 hwcap_FP = 1 << 0
15 hwcap_ASIMD = 1 << 1
16 hwcap_EVTSTRM = 1 << 2
17 hwcap_AES = 1 << 3
18 hwcap_PMULL = 1 << 4
19 hwcap_SHA1 = 1 << 5
20 hwcap_SHA2 = 1 << 6
21 hwcap_CRC32 = 1 << 7
22 hwcap_ATOMICS = 1 << 8
23 hwcap_FPHP = 1 << 9
24 hwcap_ASIMDHP = 1 << 10
25 hwcap_CPUID = 1 << 11
26 hwcap_ASIMDRDM = 1 << 12
27 hwcap_JSCVT = 1 << 13
28 hwcap_FCMA = 1 << 14
29 hwcap_LRCPC = 1 << 15
30 hwcap_DCPOP = 1 << 16
31 hwcap_SHA3 = 1 << 17
32 hwcap_SM3 = 1 << 18
33 hwcap_SM4 = 1 << 19
34 hwcap_ASIMDDP = 1 << 20
35 hwcap_SHA512 = 1 << 21
36 hwcap_SVE = 1 << 22
37 hwcap_ASIMDFHM = 1 << 23
38)
39
40// linuxKernelCanEmulateCPUID reports whether we're running
41// on Linux 4.11+. Ideally we'd like to ask the question about
42// whether the current kernel contains
43// https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=77c97b4ee21290f5f083173d957843b615abbff2
44// but the version number will have to do.
45func linuxKernelCanEmulateCPUID() bool {
46 var un syscall.Utsname
47 syscall.Uname(&un)
48 var sb strings.Builder
49 for _, b := range un.Release[:] {
50 if b == 0 {
51 break
52 }
53 sb.WriteByte(byte(b))
54 }
55 major, minor, _, ok := parseRelease(sb.String())
56 return ok && (major > 4 || major == 4 && minor >= 11)
57}
58
59func doinit() {
60 if err := readHWCAP(); err != nil {
61 // We failed to read /proc/self/auxv. This can happen if the binary has
62 // been given extra capabilities(7) with /bin/setcap.
63 //
64 // When this happens, we have two options. If the Linux kernel is new
65 // enough (4.11+), we can read the arm64 registers directly which'll
66 // trap into the kernel and then return back to userspace.
67 //
68 // But on older kernels, such as Linux 4.4.180 as used on many Synology
69 // devices, calling readARM64Registers (specifically getisar0) will
70 // cause a SIGILL and we'll die. So for older kernels, parse /proc/cpuinfo
71 // instead.
72 //
73 // See golang/go#57336.
74 if linuxKernelCanEmulateCPUID() {
75 readARM64Registers()
76 } else {
77 readLinuxProcCPUInfo()
78 }
79 return
80 }
81
82 // HWCAP feature bits
83 ARM64.HasFP = isSet(hwCap, hwcap_FP)
84 ARM64.HasASIMD = isSet(hwCap, hwcap_ASIMD)
85 ARM64.HasEVTSTRM = isSet(hwCap, hwcap_EVTSTRM)
86 ARM64.HasAES = isSet(hwCap, hwcap_AES)
87 ARM64.HasPMULL = isSet(hwCap, hwcap_PMULL)
88 ARM64.HasSHA1 = isSet(hwCap, hwcap_SHA1)
89 ARM64.HasSHA2 = isSet(hwCap, hwcap_SHA2)
90 ARM64.HasCRC32 = isSet(hwCap, hwcap_CRC32)
91 ARM64.HasATOMICS = isSet(hwCap, hwcap_ATOMICS)
92 ARM64.HasFPHP = isSet(hwCap, hwcap_FPHP)
93 ARM64.HasASIMDHP = isSet(hwCap, hwcap_ASIMDHP)
94 ARM64.HasCPUID = isSet(hwCap, hwcap_CPUID)
95 ARM64.HasASIMDRDM = isSet(hwCap, hwcap_ASIMDRDM)
96 ARM64.HasJSCVT = isSet(hwCap, hwcap_JSCVT)
97 ARM64.HasFCMA = isSet(hwCap, hwcap_FCMA)
98 ARM64.HasLRCPC = isSet(hwCap, hwcap_LRCPC)
99 ARM64.HasDCPOP = isSet(hwCap, hwcap_DCPOP)
100 ARM64.HasSHA3 = isSet(hwCap, hwcap_SHA3)
101 ARM64.HasSM3 = isSet(hwCap, hwcap_SM3)
102 ARM64.HasSM4 = isSet(hwCap, hwcap_SM4)
103 ARM64.HasASIMDDP = isSet(hwCap, hwcap_ASIMDDP)
104 ARM64.HasSHA512 = isSet(hwCap, hwcap_SHA512)
105 ARM64.HasSVE = isSet(hwCap, hwcap_SVE)
106 ARM64.HasASIMDFHM = isSet(hwCap, hwcap_ASIMDFHM)
107}
108
109func isSet(hwc uint, value uint) bool {
110 return hwc&value != 0
111}