| // Copyright 2022 The Go Authors. All rights reserved. | |
| // Use of this source code is governed by a BSD-style | |
| // license that can be found in the LICENSE file. | |
| //go:build arm64 | |
| package cpu | |
| const ( | |
| // From OpenBSD's sys/sysctl.h. | |
| _CTL_MACHDEP = 7 | |
| // From OpenBSD's machine/cpu.h. | |
| _CPU_ID_AA64ISAR0 = 2 | |
| _CPU_ID_AA64ISAR1 = 3 | |
| _CPU_ID_AA64PFR0 = 8 | |
| ) | |
| //go:noescape | |
| func sysctlUint64(mib []uint32) (uint64, bool) | |
| func osInit() { | |
| // Get ID_AA64ISAR0 from sysctl. | |
| isar0, ok := sysctlUint64([]uint32{_CTL_MACHDEP, _CPU_ID_AA64ISAR0}) | |
| if !ok { | |
| return | |
| } | |
| // Get ID_AA64PFR0 from sysctl. | |
| pfr0, ok := sysctlUint64([]uint32{_CTL_MACHDEP, _CPU_ID_AA64PFR0}) | |
| if !ok { | |
| return | |
| } | |
| parseARM64SystemRegisters(isar0, pfr0) | |
| } | |