github.com/mdaxf/iac@v0.0.0-20240519030858-58a061660378/vendor_skip/golang.org/x/sys/cpu/cpu_openbsd_arm64.go (about) 1 // Copyright 2022 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 import ( 8 "syscall" 9 "unsafe" 10 ) 11 12 // Minimal copy of functionality from x/sys/unix so the cpu package can call 13 // sysctl without depending on x/sys/unix. 14 15 const ( 16 // From OpenBSD's sys/sysctl.h. 17 _CTL_MACHDEP = 7 18 19 // From OpenBSD's machine/cpu.h. 20 _CPU_ID_AA64ISAR0 = 2 21 _CPU_ID_AA64ISAR1 = 3 22 ) 23 24 // Implemented in the runtime package (runtime/sys_openbsd3.go) 25 func syscall_syscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err syscall.Errno) 26 27 //go:linkname syscall_syscall6 syscall.syscall6 28 29 func sysctl(mib []uint32, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error) { 30 _, _, errno := syscall_syscall6(libc_sysctl_trampoline_addr, uintptr(unsafe.Pointer(&mib[0])), uintptr(len(mib)), uintptr(unsafe.Pointer(old)), uintptr(unsafe.Pointer(oldlen)), uintptr(unsafe.Pointer(new)), uintptr(newlen)) 31 if errno != 0 { 32 return errno 33 } 34 return nil 35 } 36 37 var libc_sysctl_trampoline_addr uintptr 38 39 //go:cgo_import_dynamic libc_sysctl sysctl "libc.so" 40 41 func sysctlUint64(mib []uint32) (uint64, bool) { 42 var out uint64 43 nout := unsafe.Sizeof(out) 44 if err := sysctl(mib, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0); err != nil { 45 return 0, false 46 } 47 return out, true 48 } 49 50 func doinit() { 51 setMinimalFeatures() 52 53 // Get ID_AA64ISAR0 and ID_AA64ISAR1 from sysctl. 54 isar0, ok := sysctlUint64([]uint32{_CTL_MACHDEP, _CPU_ID_AA64ISAR0}) 55 if !ok { 56 return 57 } 58 isar1, ok := sysctlUint64([]uint32{_CTL_MACHDEP, _CPU_ID_AA64ISAR1}) 59 if !ok { 60 return 61 } 62 parseARM64SystemRegisters(isar0, isar1, 0) 63 64 Initialized = true 65 }