Files
sys/cpu/cpu_loong64.go
Guoqi Chen b8f7da6c5a cpu: add support for detecting cpu features on loong64
Except for lasx, all other features have been implemented
in the Go mainline.

Change-Id: I61a09396ed23d17991b641a1265e952585cb5636
Reviewed-on: https://go-review.googlesource.com/c/sys/+/655355
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: sophie zhao <zhaoxiaolin@loongson.cn>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
Reviewed-by: Meidan Li <limeidan@loongson.cn>
2025-03-11 18:36:47 -07:00

51 lines
1.4 KiB
Go

// 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 loong64
package cpu
const cacheLineSize = 64
// Bit fields for CPUCFG registers, Related reference documents:
// https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#_cpucfg
const (
// CPUCFG1 bits
cpucfg1_CRC32 = 1 << 25
// CPUCFG2 bits
cpucfg2_LAM_BH = 1 << 27
cpucfg2_LAMCAS = 1 << 28
)
func initOptions() {
options = []option{
{Name: "lsx", Feature: &Loong64.HasLSX},
{Name: "lasx", Feature: &Loong64.HasLASX},
{Name: "crc32", Feature: &Loong64.HasCRC32},
{Name: "lam_bh", Feature: &Loong64.HasLAM_BH},
{Name: "lamcas", Feature: &Loong64.HasLAMCAS},
}
// The CPUCFG data on Loong64 only reflects the hardware capabilities,
// not the kernel support status, so features such as LSX and LASX that
// require kernel support cannot be obtained from the CPUCFG data.
//
// These features only require hardware capability support and do not
// require kernel specific support, so they can be obtained directly
// through CPUCFG
cfg1 := get_cpucfg(1)
cfg2 := get_cpucfg(2)
Loong64.HasCRC32 = cfgIsSet(cfg1, cpucfg1_CRC32)
Loong64.HasLAMCAS = cfgIsSet(cfg2, cpucfg2_LAMCAS)
Loong64.HasLAM_BH = cfgIsSet(cfg2, cpucfg2_LAM_BH)
}
func get_cpucfg(reg uint32) uint32
func cfgIsSet(cfg uint32, val uint32) bool {
return cfg&val != 0
}