vendor.github.com.templexxx.cpu.cpu_s390x.go Maven / Gradle / Ivy
// 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
const CacheLineSize = 256
// bitIsSet reports whether the bit at index is set. The bit index
// is in big endian order, so bit index 0 is the leftmost bit.
func bitIsSet(bits []uint64, index uint) bool {
return bits[index/64]&((1<<63)>>(index%64)) != 0
}
// function is the function code for the named function.
type function uint8
const (
// KM{,A,C,CTR} function codes
aes128 function = 18 // AES-128
aes192 = 19 // AES-192
aes256 = 20 // AES-256
// K{I,L}MD function codes
sha1 = 1 // SHA-1
sha256 = 2 // SHA-256
sha512 = 3 // SHA-512
// KLMD function codes
ghash = 65 // GHASH
)
// queryResult contains the result of a Query function
// call. Bits are numbered in big endian order so the
// leftmost bit (the MSB) is at index 0.
type queryResult struct {
bits [2]uint64
}
// Has reports whether the given functions are present.
func (q *queryResult) Has(fns ...function) bool {
if len(fns) == 0 {
panic("no function codes provided")
}
for _, f := range fns {
if !bitIsSet(q.bits[:], uint(f)) {
return false
}
}
return true
}
// facility is a bit index for the named facility.
type facility uint8
const (
// mandatory facilities
zarch facility = 1 // z architecture mode is active
stflef = 7 // store-facility-list-extended
ldisp = 18 // long-displacement
eimm = 21 // extended-immediate
// miscellaneous facilities
dfp = 42 // decimal-floating-point
etf3eh = 30 // extended-translation 3 enhancement
// cryptography facilities
msa = 17 // message-security-assist
msa3 = 76 // message-security-assist extension 3
msa4 = 77 // message-security-assist extension 4
msa5 = 57 // message-security-assist extension 5
msa8 = 146 // message-security-assist extension 8
// Note: vx and highgprs are excluded because they require
// kernel support and so must be fetched from HWCAP.
)
// facilityList contains the result of an STFLE call.
// Bits are numbered in big endian order so the
// leftmost bit (the MSB) is at index 0.
type facilityList struct {
bits [4]uint64
}
// Has reports whether the given facilities are present.
func (s *facilityList) Has(fs ...facility) bool {
if len(fs) == 0 {
panic("no facility bits provided")
}
for _, f := range fs {
if !bitIsSet(s.bits[:], uint(f)) {
return false
}
}
return true
}
// The following feature detection functions are defined in cpu_s390x.s.
// They are likely to be expensive to call so the results should be cached.
func stfle() facilityList
func kmQuery() queryResult
func kmcQuery() queryResult
func kmctrQuery() queryResult
func kmaQuery() queryResult
func kimdQuery() queryResult
func klmdQuery() queryResult
func doinit() {
options = []option{
{"zarch", &S390X.HasZArch},
{"stfle", &S390X.HasSTFLE},
{"ldisp", &S390X.HasLDisp},
{"msa", &S390X.HasMSA},
{"eimm", &S390X.HasEImm},
{"dfp", &S390X.HasDFP},
{"etf3eh", &S390X.HasETF3Enhanced},
{"vx", &S390X.HasVX},
}
aes := []function{aes128, aes192, aes256}
facilities := stfle()
S390X.HasZArch = facilities.Has(zarch)
S390X.HasSTFLE = facilities.Has(stflef)
S390X.HasLDisp = facilities.Has(ldisp)
S390X.HasEImm = facilities.Has(eimm)
S390X.HasDFP = facilities.Has(dfp)
S390X.HasETF3Enhanced = facilities.Has(etf3eh)
S390X.HasMSA = facilities.Has(msa)
if S390X.HasMSA {
// cipher message
km, kmc := kmQuery(), kmcQuery()
S390X.HasAES = km.Has(aes...)
S390X.HasAESCBC = kmc.Has(aes...)
if facilities.Has(msa4) {
kmctr := kmctrQuery()
S390X.HasAESCTR = kmctr.Has(aes...)
}
if facilities.Has(msa8) {
kma := kmaQuery()
S390X.HasAESGCM = kma.Has(aes...)
}
// compute message digest
kimd := kimdQuery() // intermediate (no padding)
klmd := klmdQuery() // last (padding)
S390X.HasSHA1 = kimd.Has(sha1) && klmd.Has(sha1)
S390X.HasSHA256 = kimd.Has(sha256) && klmd.Has(sha256)
S390X.HasSHA512 = kimd.Has(sha512) && klmd.Has(sha512)
S390X.HasGHASH = kimd.Has(ghash) // KLMD-GHASH does not exist
}
}