blob: 85210aa00c72676922f9fbf5ef0ac62d5e45c480 [file] [log] [blame]
// Copyright 2017 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.
package cpu
// CacheLinePadSize is used to prevent false sharing of cache lines.
// We choose 128 because Apple Silicon, a.k.a. M1, has 128-byte cache line size.
// It doesn't cost much and is much more future-proof.
const CacheLinePadSize = 128
func doinit() {
options = []option{
{Name: "aes", Feature: &ARM64.HasAES},
{Name: "pmull", Feature: &ARM64.HasPMULL},
{Name: "sha1", Feature: &ARM64.HasSHA1},
{Name: "sha2", Feature: &ARM64.HasSHA2},
{Name: "sha512", Feature: &ARM64.HasSHA512},
{Name: "crc32", Feature: &ARM64.HasCRC32},
{Name: "atomics", Feature: &ARM64.HasATOMICS},
{Name: "cpuid", Feature: &ARM64.HasCPUID},
{Name: "isNeoverseN1", Feature: &ARM64.IsNeoverseN1},
{Name: "isNeoverseV1", Feature: &ARM64.IsNeoverseV1},
}
// arm64 uses different ways to detect CPU features at runtime depending on the operating system.
osInit()
}
func getisar0() uint64
func getMIDR() uint64
func extractBits(data uint64, start, end uint) uint {
return (uint)(data>>start) & ((1 << (end - start + 1)) - 1)
}
func parseARM64SystemRegisters(isar0 uint64) {
// ID_AA64ISAR0_EL1
switch extractBits(isar0, 4, 7) {
case 1:
ARM64.HasAES = true
case 2:
ARM64.HasAES = true
ARM64.HasPMULL = true
}
switch extractBits(isar0, 8, 11) {
case 1:
ARM64.HasSHA1 = true
}
switch extractBits(isar0, 12, 15) {
case 1:
ARM64.HasSHA2 = true
case 2:
ARM64.HasSHA2 = true
ARM64.HasSHA512 = true
}
switch extractBits(isar0, 16, 19) {
case 1:
ARM64.HasCRC32 = true
}
switch extractBits(isar0, 20, 23) {
case 2:
ARM64.HasATOMICS = true
}
}