S390X Support (#274)

* support for s390x

* added z15 T01, T02 model checking

* removed z15 checking

* removed empty strings

* added s390x unit tests

* added reference url for hwcaps

* moved documentation to S390XFeatures struct, updated copyright date, removed unused include statement

* changed num_processors to int

* removed newlines from test inputs

* scripts: Add bootlin s390x support

* cmake(ci): Add s390x support

* ci: Add s390x workflow

Co-authored-by: Marcos <marcos.araque.fiallos@ibm.com>
Co-authored-by: Corentin Le Molgat <corentinl@google.com>

3 files changed, 140 insertions, 0 deletions

diff --git a/include/cpu_features_macros.h b/include/cpu_features_macros.h
index 09f8297..b759220 100644
--- a/include/cpu_features_macros.h
+++ b/include/cpu_features_macros.h
@@ -63,6 +63,10 @@
 #define CPU_FEATURES_ARCH_PPC
 #endif
 
+#if defined(__s390x__)
+#define CPU_FEATURES_ARCH_S390X
+#endif
+
 #if defined(__riscv)
 #define CPU_FEATURES_ARCH_RISCV
 #endif
diff --git a/include/cpuinfo_s390x.h b/include/cpuinfo_s390x.h
new file mode 100644
index 0000000..48864de
--- /dev/null
+++ b/include/cpuinfo_s390x.h
@@ -0,0 +1,108 @@
+// Copyright 2022 IBM
+//
+// 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.
+
+#ifndef CPU_FEATURES_INCLUDE_CPUINFO_S390X_H_
+#define CPU_FEATURES_INCLUDE_CPUINFO_S390X_H_
+
+#include "cpu_features_cache_info.h"
+#include "cpu_features_macros.h"
+
+CPU_FEATURES_START_CPP_NAMESPACE
+
+typedef struct {
+  int esan3: 1;     // instructions named N3, "backported" to esa-mode
+  int zarch: 1;     // z/Architecture mode active
+  int stfle: 1;     // store-facility-list-extended
+  int msa: 1;       // message-security assist
+  int ldisp: 1;     // long-displacement
+  int eimm: 1;      // extended-immediate
+  int dfp: 1;       // decimal floating point & perform floating point operation
+  int edat: 1;      // huge page support
+  int etf3eh: 1;    // extended-translation facility 3 enhancement
+  int highgprs: 1;  // 64-bit register support for 31-bit processes
+  int te: 1;        // transactional execution
+  int vx: 1;        // vector extension facility
+  int vxd: 1;       // vector-packed-decimal facility
+  int vxe: 1;       // vector-enhancement facility 1
+  int gs: 1;        // guarded-storage facility
+  int vxe2: 1;      // vector-enhancements facility 2
+  int vxp: 1;       // vector-packed-decimal-enhancement facility
+  int sort: 1;      // enhanced-sort facility
+  int dflt: 1;      // deflate-conversion facility
+  int vxp2: 1;      // vector-packed-decimal-enhancement facility 2
+  int nnpa: 1;      // neural network processing assist facility
+  int pcimio: 1;    // PCI mio facility
+  int sie: 1;       // virtualization support
+
+  // Make sure to update S390XFeaturesEnum below if you add a field here.
+} S390XFeatures;
+
+typedef struct {
+  S390XFeatures features;
+} S390XInfo;
+
+S390XInfo GetS390XInfo(void);
+
+typedef struct {
+  char platform[64];       // 0 terminated string
+} S390XPlatformTypeStrings;
+
+typedef struct {
+  int num_processors;      // -1 if N/A
+  S390XPlatformTypeStrings type;
+} S390XPlatformStrings;
+
+S390XPlatformStrings GetS390XPlatformStrings(void);
+
+////////////////////////////////////////////////////////////////////////////////
+// Introspection functions
+
+typedef enum {
+  S390_ESAN3,
+  S390_ZARCH,
+  S390_STFLE,
+  S390_MSA,
+  S390_LDISP,
+  S390_EIMM,
+  S390_DFP,
+  S390_EDAT,
+  S390_ETF3EH,
+  S390_HIGHGPRS,
+  S390_TE,
+  S390_VX,
+  S390_VXD,
+  S390_VXE,
+  S390_GS,
+  S390_VXE2,
+  S390_VXP,
+  S390_SORT,
+  S390_DFLT,
+  S390_VXP2,
+  S390_NNPA,
+  S390_PCIMIO,
+  S390_SIE,
+  S390X_LAST_,
+} S390XFeaturesEnum;
+
+int GetS390XFeaturesEnumValue(const S390XFeatures* features, S390XFeaturesEnum value);
+
+const char* GetS390XFeaturesEnumName(S390XFeaturesEnum);
+
+CPU_FEATURES_END_CPP_NAMESPACE
+
+#if !defined(CPU_FEATURES_ARCH_S390X)
+#error "Including cpuinfo_s390x.h from a non-s390x target."
+#endif
+
+#endif  // CPU_FEATURES_INCLUDE_CPUINFO_S390X_H_
diff --git a/include/internal/hwcaps.h b/include/internal/hwcaps.h
index f916b81..5030582 100644
--- a/include/internal/hwcaps.h
+++ b/include/internal/hwcaps.h
@@ -176,6 +176,34 @@ CPU_FEATURES_START_CPP_NAMESPACE
 #define PPC_FEATURE2_HTM_NO_SUSPEND 0x00080000
 #endif
 
+// https://elixir.bootlin.com/linux/v6.0-rc6/source/arch/s390/include/asm/elf.h
+#define HWCAP_S390_ESAN3        1
+#define HWCAP_S390_ZARCH        2
+#define HWCAP_S390_STFLE        4
+#define HWCAP_S390_MSA          8
+#define HWCAP_S390_LDISP        16
+#define HWCAP_S390_EIMM         32
+#define HWCAP_S390_DFP          64
+#define HWCAP_S390_HPAGE        128
+#define HWCAP_S390_ETF3EH       256
+#define HWCAP_S390_HIGH_GPRS    512
+#define HWCAP_S390_TE           1024
+#define HWCAP_S390_VX           2048
+#define HWCAP_S390_VXRS         HWCAP_S390_VX
+#define HWCAP_S390_VXD          4096
+#define HWCAP_S390_VXRS_BCD     HWCAP_S390_VXD
+#define HWCAP_S390_VXE          8192
+#define HWCAP_S390_VXRS_EXT     HWCAP_S390_VXE
+#define HWCAP_S390_GS           16384
+#define HWCAP_S390_VXRS_EXT2    32768
+#define HWCAP_S390_VXRS_PDE     65536
+#define HWCAP_S390_SORT         131072
+#define HWCAP_S390_DFLT         262144
+#define HWCAP_S390_VXRS_PDE2    524288
+#define HWCAP_S390_NNPA         1048576
+#define HWCAP_S390_PCI_MIO      2097152
+#define HWCAP_S390_SIE          4194304
+
 // https://elixir.bootlin.com/linux/latest/source/arch/riscv/include/uapi/asm/hwcap.h
 #define RISCV_HWCAP_A (1UL << ('A' - 'A'))
 #define RISCV_HWCAP_C (1UL << ('C' - 'A'))