Merge pull request #322 from adaptant-labs/cpuid-arm

cpu: Add support for ARM/Aarch32 cpuid

README.md

@@ -250,6 +250,23 @@ capability might be supported but not enabled.
 | AVX       | Advanced Vector Extensions (AVX)
 | AVX2      | Advanced Vector Extensions 2 (AVX2)
 
+#### Arm CPUID Attribute (Partial List)
+
+| Attribute | Description                                                      |
+| --------- | ---------------------------------------------------------------- |
+| IDIVA     | Integer divide instructions available in ARM mode
+| IDIVT     | Integer divide instructions available in Thumb mode
+| THUMB     | Thumb instructions
+| FASTMUL   | Fast multiplication
+| VFP       | Vector floating point instruction extension (VFP)
+| VFPv3     | Vector floating point extension v3
+| VFPv4     | Vector floating point extension v4
+| VFPD32    | VFP with 32 D-registers
+| HALF      | Half-word loads and stores
+| EDSP      | DSP extensions
+| NEON      | NEON SIMD instructions
+| LPAE      | Large Physical Address Extensions
+
 #### Arm64 CPUID Attribute (Partial List)
 
 | Attribute | Description                                                      |
@@ -660,7 +677,7 @@ If you want to use the latest development version (master branch) you need to
 
 ### System requirements
 
-1. Linux (x86_64/Arm64)
+1. Linux (x86_64/Arm64/Arm)
 1. [kubectl][kubectl-setup] (properly set up and configured to work with your
    Kubernetes cluster)
 1. [Docker][docker-down] (only required to build and push docker images)

source/cpu/cpuid_arm.go

@@ -0,0 +1,104 @@
+/*
+Copyright 2020 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cpu
+
+/*
+#include <sys/auxv.h>
+#define HWCAP_CPUID	(1 << 11)
+
+unsigned long gethwcap() {
+	return getauxval(AT_HWCAP);
+}
+*/
+import "C"
+
+/* all special features for arm should be defined here */
+const (
+	/* extension instructions */
+	CPU_ARM_FEATURE_SWP = 1 << iota
+	CPU_ARM_FEATURE_HALF
+	CPU_ARM_FEATURE_THUMB
+	CPU_ARM_FEATURE_26BIT
+	CPU_ARM_FEATURE_FASTMUL
+	CPU_ARM_FEATURE_FPA
+	CPU_ARM_FEATURE_VFP
+	CPU_ARM_FEATURE_EDSP
+	CPU_ARM_FEATURE_JAVA
+	CPU_ARM_FEATURE_IWMMXT
+	CPU_ARM_FEATURE_CRUNCH
+	CPU_ARM_FEATURE_THUMBEE
+	CPU_ARM_FEATURE_NEON
+	CPU_ARM_FEATURE_VFPv3
+	CPU_ARM_FEATURE_VFPv3D16
+	CPU_ARM_FEATURE_TLS
+	CPU_ARM_FEATURE_VFPv4
+	CPU_ARM_FEATURE_IDIVA
+	CPU_ARM_FEATURE_IDIVT
+	CPU_ARM_FEATURE_IDIV
+	CPU_ARM_FEATURE_VFPD32
+	CPU_ARM_FEATURE_LPAE
+	CPU_ARM_FEATURE_EVTSTRM
+	CPU_ARM_FEATURE_AES
+	CPU_ARM_FEATURE_PMULL
+	CPU_ARM_FEATURE_SHA1
+	CPU_ARM_FEATURE_SHA2
+	CPU_ARM_FEATURE_CRC32
+)
+
+var flagNames_arm = map[uint64]string{
+	CPU_ARM_FEATURE_SWP:      "SWP",
+	CPU_ARM_FEATURE_HALF:     "HALF",
+	CPU_ARM_FEATURE_THUMB:    "THUMB",
+	CPU_ARM_FEATURE_26BIT:    "26BIT",
+	CPU_ARM_FEATURE_FASTMUL:  "FASTMUL",
+	CPU_ARM_FEATURE_FPA:      "FPA",
+	CPU_ARM_FEATURE_VFP:      "VFP",
+	CPU_ARM_FEATURE_EDSP:     "EDSP",
+	CPU_ARM_FEATURE_JAVA:     "JAVA",
+	CPU_ARM_FEATURE_IWMMXT:   "IWMMXT",
+	CPU_ARM_FEATURE_CRUNCH:   "CRUNCH",
+	CPU_ARM_FEATURE_THUMBEE:  "THUMBEE",
+	CPU_ARM_FEATURE_NEON:     "NEON",
+	CPU_ARM_FEATURE_VFPv3:    "VFPv3",
+	CPU_ARM_FEATURE_VFPv3D16: "VFPv3D16",
+	CPU_ARM_FEATURE_TLS:      "TLS",
+	CPU_ARM_FEATURE_VFPv4:    "VFPv4",
+	CPU_ARM_FEATURE_IDIVA:    "IDIVA",
+	CPU_ARM_FEATURE_IDIVT:    "IDIVT",
+	CPU_ARM_FEATURE_IDIV:     "IDIV",
+	CPU_ARM_FEATURE_VFPD32:   "VFPD32",
+	CPU_ARM_FEATURE_LPAE:     "LPAE",
+	CPU_ARM_FEATURE_EVTSTRM:  "EVTSTRM",
+	CPU_ARM_FEATURE_AES:      "AES",
+	CPU_ARM_FEATURE_PMULL:    "PMULL",
+	CPU_ARM_FEATURE_SHA1:     "SHA1",
+	CPU_ARM_FEATURE_SHA2:     "SHA2",
+	CPU_ARM_FEATURE_CRC32:    "CRC32",
+}
+
+func getCpuidFlags() []string {
+	r := make([]string, 0, 20)
+	hwcap := uint64(C.gethwcap())
+	for i := uint(0); i < 64; i++ {
+		key := uint64(1 << i)
+		val := flagNames_arm[key]
+		if hwcap&key != 0 {
+			r = append(r, val)
+		}
+	}
+	return r
+}