github.com/nibnait/go-learn@v0.0.0-20220227013611-dfa47ea6d2da/src/pkg/mod/golang.org/x/sys@v0.0.0-20210630005230-0f9fa26af87c/cpu/cpu_linux_arm64.go (about)

     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  
     5  package cpu
     6  
     7  // HWCAP/HWCAP2 bits. These are exposed by Linux.
     8  const (
     9  	hwcap_FP       = 1 << 0
    10  	hwcap_ASIMD    = 1 << 1
    11  	hwcap_EVTSTRM  = 1 << 2
    12  	hwcap_AES      = 1 << 3
    13  	hwcap_PMULL    = 1 << 4
    14  	hwcap_SHA1     = 1 << 5
    15  	hwcap_SHA2     = 1 << 6
    16  	hwcap_CRC32    = 1 << 7
    17  	hwcap_ATOMICS  = 1 << 8
    18  	hwcap_FPHP     = 1 << 9
    19  	hwcap_ASIMDHP  = 1 << 10
    20  	hwcap_CPUID    = 1 << 11
    21  	hwcap_ASIMDRDM = 1 << 12
    22  	hwcap_JSCVT    = 1 << 13
    23  	hwcap_FCMA     = 1 << 14
    24  	hwcap_LRCPC    = 1 << 15
    25  	hwcap_DCPOP    = 1 << 16
    26  	hwcap_SHA3     = 1 << 17
    27  	hwcap_SM3      = 1 << 18
    28  	hwcap_SM4      = 1 << 19
    29  	hwcap_ASIMDDP  = 1 << 20
    30  	hwcap_SHA512   = 1 << 21
    31  	hwcap_SVE      = 1 << 22
    32  	hwcap_ASIMDFHM = 1 << 23
    33  )
    34  
    35  func doinit() {
    36  	if err := readHWCAP(); err != nil {
    37  		// failed to read /proc/self/auxv, try reading registers directly
    38  		readARM64Registers()
    39  		return
    40  	}
    41  
    42  	// HWCAP feature bits
    43  	ARM64.HasFP = isSet(hwCap, hwcap_FP)
    44  	ARM64.HasASIMD = isSet(hwCap, hwcap_ASIMD)
    45  	ARM64.HasEVTSTRM = isSet(hwCap, hwcap_EVTSTRM)
    46  	ARM64.HasAES = isSet(hwCap, hwcap_AES)
    47  	ARM64.HasPMULL = isSet(hwCap, hwcap_PMULL)
    48  	ARM64.HasSHA1 = isSet(hwCap, hwcap_SHA1)
    49  	ARM64.HasSHA2 = isSet(hwCap, hwcap_SHA2)
    50  	ARM64.HasCRC32 = isSet(hwCap, hwcap_CRC32)
    51  	ARM64.HasATOMICS = isSet(hwCap, hwcap_ATOMICS)
    52  	ARM64.HasFPHP = isSet(hwCap, hwcap_FPHP)
    53  	ARM64.HasASIMDHP = isSet(hwCap, hwcap_ASIMDHP)
    54  	ARM64.HasCPUID = isSet(hwCap, hwcap_CPUID)
    55  	ARM64.HasASIMDRDM = isSet(hwCap, hwcap_ASIMDRDM)
    56  	ARM64.HasJSCVT = isSet(hwCap, hwcap_JSCVT)
    57  	ARM64.HasFCMA = isSet(hwCap, hwcap_FCMA)
    58  	ARM64.HasLRCPC = isSet(hwCap, hwcap_LRCPC)
    59  	ARM64.HasDCPOP = isSet(hwCap, hwcap_DCPOP)
    60  	ARM64.HasSHA3 = isSet(hwCap, hwcap_SHA3)
    61  	ARM64.HasSM3 = isSet(hwCap, hwcap_SM3)
    62  	ARM64.HasSM4 = isSet(hwCap, hwcap_SM4)
    63  	ARM64.HasASIMDDP = isSet(hwCap, hwcap_ASIMDDP)
    64  	ARM64.HasSHA512 = isSet(hwCap, hwcap_SHA512)
    65  	ARM64.HasSVE = isSet(hwCap, hwcap_SVE)
    66  	ARM64.HasASIMDFHM = isSet(hwCap, hwcap_ASIMDFHM)
    67  }
    68  
    69  func isSet(hwc uint, value uint) bool {
    70  	return hwc&value != 0
    71  }