/*

 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.

 * Copyright (c) 2015, 2019, Red Hat Inc. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "asm/macroAssembler.hpp"

#include "asm/macroAssembler.inline.hpp"

#include "memory/resourceArea.hpp"

#include "runtime/java.hpp"

#include "runtime/os.hpp"

#include "runtime/stubCodeGenerator.hpp"

#include "utilities/macros.hpp"

#include OS_HEADER_INLINE(os)

#include <sys/auxv.h>

#include <asm/hwcap.h>

#ifndef HWCAP_AES

#define HWCAP_AES   (1<<3)

#endif

#ifndef HWCAP_PMULL

#define HWCAP_PMULL (1<<4)

#endif

#ifndef HWCAP_SHA1

#define HWCAP_SHA1  (1<<5)

#endif

#ifndef HWCAP_SHA2

#define HWCAP_SHA2  (1<<6)

#endif

#ifndef HWCAP_CRC32

#define HWCAP_CRC32 (1<<7)

#endif

#ifndef HWCAP_ATOMICS

#define HWCAP_ATOMICS (1<<8)

#endif

int VM_Version::_cpu;

int VM_Version::_model;

int VM_Version::_model2;

int VM_Version::_variant;

int VM_Version::_revision;

int VM_Version::_stepping;

bool VM_Version::_dcpop;

VM_Version::PsrInfo VM_Version::_psr_info   = { 0, };

static BufferBlob* stub_blob;

static const int stub_size = 550;

extern "C" {

  typedef void (*getPsrInfo_stub_t)(void*);

}

static getPsrInfo_stub_t getPsrInfo_stub = NULL;

class VM_Version_StubGenerator: public StubCodeGenerator {

 public:

  VM_Version_StubGenerator(CodeBuffer *c) : StubCodeGenerator(c) {}

  address generate_getPsrInfo() {

    StubCodeMark mark(this, "VM_Version", "getPsrInfo_stub");

#   define __ _masm->

    address start = __ pc();

    // void getPsrInfo(VM_Version::PsrInfo* psr_info);

    address entry = __ pc();

    __ enter();

    __ get_dczid_el0(rscratch1);

    __ strw(rscratch1, Address(c_rarg0, in_bytes(VM_Version::dczid_el0_offset())));

    __ get_ctr_el0(rscratch1);

    __ strw(rscratch1, Address(c_rarg0, in_bytes(VM_Version::ctr_el0_offset())));

    __ leave();

    __ ret(lr);

#   undef __

    return start;

  }

};

void VM_Version::get_processor_features() {

  _supports_cx8 = true;

  _supports_atomic_getset4 = true;

  _supports_atomic_getadd4 = true;

  _supports_atomic_getset8 = true;

  _supports_atomic_getadd8 = true;

  getPsrInfo_stub(&_psr_info);

  int dcache_line = VM_Version::dcache_line_size();

  // Limit AllocatePrefetchDistance so that it does not exceed the

  // constraint in AllocatePrefetchDistanceConstraintFunc.

  if (FLAG_IS_DEFAULT(AllocatePrefetchDistance))

    FLAG_SET_DEFAULT(AllocatePrefetchDistance, MIN2(512, 3*dcache_line));

  if (FLAG_IS_DEFAULT(AllocatePrefetchStepSize))

    FLAG_SET_DEFAULT(AllocatePrefetchStepSize, dcache_line);

  if (FLAG_IS_DEFAULT(PrefetchScanIntervalInBytes))

    FLAG_SET_DEFAULT(PrefetchScanIntervalInBytes, 3*dcache_line);

  if (FLAG_IS_DEFAULT(PrefetchCopyIntervalInBytes))

    FLAG_SET_DEFAULT(PrefetchCopyIntervalInBytes, 3*dcache_line);

  if (FLAG_IS_DEFAULT(SoftwarePrefetchHintDistance))

    FLAG_SET_DEFAULT(SoftwarePrefetchHintDistance, 3*dcache_line);

  if (PrefetchCopyIntervalInBytes != -1 &&

       ((PrefetchCopyIntervalInBytes & 7) || (PrefetchCopyIntervalInBytes >= 32768))) {

    warning("PrefetchCopyIntervalInBytes must be -1, or a multiple of 8 and < 32768");

    PrefetchCopyIntervalInBytes &= ~7;

    if (PrefetchCopyIntervalInBytes >= 32768)

      PrefetchCopyIntervalInBytes = 32760;

  }

  if (AllocatePrefetchDistance !=-1 && (AllocatePrefetchDistance & 7)) {

    warning("AllocatePrefetchDistance must be multiple of 8");

    AllocatePrefetchDistance &= ~7;

  }

  if (AllocatePrefetchStepSize & 7) {

    warning("AllocatePrefetchStepSize must be multiple of 8");

    AllocatePrefetchStepSize &= ~7;

  }

  if (SoftwarePrefetchHintDistance != -1 &&

       (SoftwarePrefetchHintDistance & 7)) {

    warning("SoftwarePrefetchHintDistance must be -1, or a multiple of 8");

    SoftwarePrefetchHintDistance &= ~7;

  }

  unsigned long auxv = getauxval(AT_HWCAP);

  char buf[512];

  _features = auxv;

  int cpu_lines = 0;

  if (FILE *f = fopen("/proc/cpuinfo", "r")) {

    // need a large buffer as the flags line may include lots of text

    char buf[1024], *p;

    while (fgets(buf, sizeof (buf), f) != NULL) {

      if ((p = strchr(buf, ':')) != NULL) {

        long v = strtol(p+1, NULL, 0);

        if (strncmp(buf, "CPU implementer", sizeof "CPU implementer" - 1) == 0) {

          _cpu = v;

          cpu_lines++;

        } else if (strncmp(buf, "CPU variant", sizeof "CPU variant" - 1) == 0) {

          _variant = v;

        } else if (strncmp(buf, "CPU part", sizeof "CPU part" - 1) == 0) {

          if (_model != v)  _model2 = _model;

          _model = v;

        } else if (strncmp(buf, "CPU revision", sizeof "CPU revision" - 1) == 0) {

          _revision = v;

        } else if (strncmp(buf, "flags", sizeof("flags") - 1) == 0) {

          if (strstr(p+1, "dcpop")) {

            _dcpop = true;

          }

        }

      }

    }

    fclose(f);

  }

  if (os::supports_map_sync()) {

    // if dcpop is available publish data cache line flush size via

    // generic field, otherwise let if default to zero thereby

    // disabling writeback

    if (_dcpop) {

      _data_cache_line_flush_size = dcache_line;

    }

  }

  // Enable vendor specific features

  // Ampere eMAG

  if (_cpu == CPU_AMCC && (_model == 0) && (_variant == 0x3)) {

    if (FLAG_IS_DEFAULT(AvoidUnalignedAccesses)) {

      FLAG_SET_DEFAULT(AvoidUnalignedAccesses, true);

    }

    if (FLAG_IS_DEFAULT(UseSIMDForMemoryOps)) {

      FLAG_SET_DEFAULT(UseSIMDForMemoryOps, true);

    }

    if (FLAG_IS_DEFAULT(UseSIMDForArrayEquals)) {

      FLAG_SET_DEFAULT(UseSIMDForArrayEquals, !(_revision == 1 || _revision == 2));

    }

  }

  // ThunderX

  if (_cpu == CPU_CAVIUM && (_model == 0xA1)) {

    if (_variant == 0) _features |= CPU_DMB_ATOMICS;

    if (FLAG_IS_DEFAULT(AvoidUnalignedAccesses)) {

      FLAG_SET_DEFAULT(AvoidUnalignedAccesses, true);

    }

    if (FLAG_IS_DEFAULT(UseSIMDForMemoryOps)) {

      FLAG_SET_DEFAULT(UseSIMDForMemoryOps, (_variant > 0));

    }

    if (FLAG_IS_DEFAULT(UseSIMDForArrayEquals)) {

      FLAG_SET_DEFAULT(UseSIMDForArrayEquals, false);

    }

  }

  // ThunderX2

  if ((_cpu == CPU_CAVIUM && (_model == 0xAF)) ||

      (_cpu == CPU_BROADCOM && (_model == 0x516))) {

    if (FLAG_IS_DEFAULT(AvoidUnalignedAccesses)) {

      FLAG_SET_DEFAULT(AvoidUnalignedAccesses, true);

    }

    if (FLAG_IS_DEFAULT(UseSIMDForMemoryOps)) {

      FLAG_SET_DEFAULT(UseSIMDForMemoryOps, true);

    }

  }

  // HiSilicon TSV110

  if (_cpu == CPU_HISILICON && _model == 0xd01) {

    if (FLAG_IS_DEFAULT(AvoidUnalignedAccesses)) {

      FLAG_SET_DEFAULT(AvoidUnalignedAccesses, true);

    }

    if (FLAG_IS_DEFAULT(UseSIMDForMemoryOps)) {

      FLAG_SET_DEFAULT(UseSIMDForMemoryOps, true);

    }

  }

  // Cortex A53

  if (_cpu == CPU_ARM && (_model == 0xd03 || _model2 == 0xd03)) {

    _features |= CPU_A53MAC;

    if (FLAG_IS_DEFAULT(UseSIMDForArrayEquals)) {

      FLAG_SET_DEFAULT(UseSIMDForArrayEquals, false);

    }

  }

  // Cortex A73

  if (_cpu == CPU_ARM && (_model == 0xd09 || _model2 == 0xd09)) {

    if (FLAG_IS_DEFAULT(SoftwarePrefetchHintDistance)) {

      FLAG_SET_DEFAULT(SoftwarePrefetchHintDistance, -1);

    }

    // A73 is faster with short-and-easy-for-speculative-execution-loop

    if (FLAG_IS_DEFAULT(UseSimpleArrayEquals)) {

      FLAG_SET_DEFAULT(UseSimpleArrayEquals, true);

    }

  }

  if (_cpu == CPU_ARM && (_model == 0xd07 || _model2 == 0xd07)) _features |= CPU_STXR_PREFETCH;

  // If an olde style /proc/cpuinfo (cpu_lines == 1) then if _model is an A57 (0xd07)

  // we assume the worst and assume we could be on a big little system and have

  // undisclosed A53 cores which we could be swapped to at any stage

  if (_cpu == CPU_ARM && cpu_lines == 1 && _model == 0xd07) _features |= CPU_A53MAC;

  sprintf(buf, "0x%02x:0x%x:0x%03x:%d", _cpu, _variant, _model, _revision);

  if (_model2) sprintf(buf+strlen(buf), "(0x%03x)", _model2);

  if (auxv & HWCAP_ASIMD) strcat(buf, ", simd");

  if (auxv & HWCAP_CRC32) strcat(buf, ", crc");

  if (auxv & HWCAP_AES)   strcat(buf, ", aes");

  if (auxv & HWCAP_SHA1)  strcat(buf, ", sha1");

  if (auxv & HWCAP_SHA2)  strcat(buf, ", sha256");

  if (auxv & HWCAP_ATOMICS) strcat(buf, ", lse");

  _features_string = os::strdup(buf);

  if (FLAG_IS_DEFAULT(UseCRC32)) {

    UseCRC32 = (auxv & HWCAP_CRC32) != 0;

  }

  if (UseCRC32 && (auxv & HWCAP_CRC32) == 0) {

    warning("UseCRC32 specified, but not supported on this CPU");

    FLAG_SET_DEFAULT(UseCRC32, false);

  }

  if (FLAG_IS_DEFAULT(UseAdler32Intrinsics)) {

    FLAG_SET_DEFAULT(UseAdler32Intrinsics, true);

  }

  if (UseVectorizedMismatchIntrinsic) {

    warning("UseVectorizedMismatchIntrinsic specified, but not available on this CPU.");

    FLAG_SET_DEFAULT(UseVectorizedMismatchIntrinsic, false);

  }

  if (auxv & HWCAP_ATOMICS) {

    if (FLAG_IS_DEFAULT(UseLSE))

      FLAG_SET_DEFAULT(UseLSE, true);

  } else {

    if (UseLSE) {

      warning("UseLSE specified, but not supported on this CPU");

      FLAG_SET_DEFAULT(UseLSE, false);

    }

  }

  if (auxv & HWCAP_AES) {

    UseAES = UseAES || FLAG_IS_DEFAULT(UseAES);

    UseAESIntrinsics =

        UseAESIntrinsics || (UseAES && FLAG_IS_DEFAULT(UseAESIntrinsics));

    if (UseAESIntrinsics && !UseAES) {

      warning("UseAESIntrinsics enabled, but UseAES not, enabling");

      UseAES = true;

    }

  } else {

    if (UseAES) {

      warning("UseAES specified, but not supported on this CPU");

      FLAG_SET_DEFAULT(UseAES, false);

    }

    if (UseAESIntrinsics) {

      warning("UseAESIntrinsics specified, but not supported on this CPU");

      FLAG_SET_DEFAULT(UseAESIntrinsics, false);

    }

  }

  if (UseAESCTRIntrinsics) {

    warning("AES/CTR intrinsics are not available on this CPU");

    FLAG_SET_DEFAULT(UseAESCTRIntrinsics, false);

  }

  if (FLAG_IS_DEFAULT(UseCRC32Intrinsics)) {

    UseCRC32Intrinsics = true;

  }

  if (auxv & HWCAP_CRC32) {

    if (FLAG_IS_DEFAULT(UseCRC32CIntrinsics)) {

      FLAG_SET_DEFAULT(UseCRC32CIntrinsics, true);

    }

  } else if (UseCRC32CIntrinsics) {

    warning("CRC32C is not available on the CPU");

    FLAG_SET_DEFAULT(UseCRC32CIntrinsics, false);

  }

  if (FLAG_IS_DEFAULT(UseFMA)) {

    FLAG_SET_DEFAULT(UseFMA, true);

  }

  if (auxv & (HWCAP_SHA1 | HWCAP_SHA2)) {

    if (FLAG_IS_DEFAULT(UseSHA)) {

      FLAG_SET_DEFAULT(UseSHA, true);

    }

  } else if (UseSHA) {

    warning("SHA instructions are not available on this CPU");

    FLAG_SET_DEFAULT(UseSHA, false);

  }

  if (UseSHA && (auxv & HWCAP_SHA1)) {

    if (FLAG_IS_DEFAULT(UseSHA1Intrinsics)) {

      FLAG_SET_DEFAULT(UseSHA1Intrinsics, true);

    }

  } else if (UseSHA1Intrinsics) {

    warning("Intrinsics for SHA-1 crypto hash functions not available on this CPU.");

    FLAG_SET_DEFAULT(UseSHA1Intrinsics, false);

  }

  if (UseSHA && (auxv & HWCAP_SHA2)) {

    if (FLAG_IS_DEFAULT(UseSHA256Intrinsics)) {

      FLAG_SET_DEFAULT(UseSHA256Intrinsics, true);

    }

  } else if (UseSHA256Intrinsics) {

    warning("Intrinsics for SHA-224 and SHA-256 crypto hash functions not available on this CPU.");

    FLAG_SET_DEFAULT(UseSHA256Intrinsics, false);

  }

  if (UseSHA512Intrinsics) {

    warning("Intrinsics for SHA-384 and SHA-512 crypto hash functions not available on this CPU.");

    FLAG_SET_DEFAULT(UseSHA512Intrinsics, false);

  }

  if (!(UseSHA1Intrinsics || UseSHA256Intrinsics || UseSHA512Intrinsics)) {

    FLAG_SET_DEFAULT(UseSHA, false);

  }

  if (auxv & HWCAP_PMULL) {

    if (FLAG_IS_DEFAULT(UseGHASHIntrinsics)) {

      FLAG_SET_DEFAULT(UseGHASHIntrinsics, true);

    }

  } else if (UseGHASHIntrinsics) {

    warning("GHASH intrinsics are not available on this CPU");

    FLAG_SET_DEFAULT(UseGHASHIntrinsics, false);

  }

  if (is_zva_enabled()) {

    if (FLAG_IS_DEFAULT(UseBlockZeroing)) {

      FLAG_SET_DEFAULT(UseBlockZeroing, true);

    }

    if (FLAG_IS_DEFAULT(BlockZeroingLowLimit)) {

      FLAG_SET_DEFAULT(BlockZeroingLowLimit, 4 * VM_Version::zva_length());

    }

  } else if (UseBlockZeroing) {

    warning("DC ZVA is not available on this CPU");

    FLAG_SET_DEFAULT(UseBlockZeroing, false);

  }

  // This machine allows unaligned memory accesses

  if (FLAG_IS_DEFAULT(UseUnalignedAccesses)) {

    FLAG_SET_DEFAULT(UseUnalignedAccesses, true);

  }

  if (FLAG_IS_DEFAULT(UseBarriersForVolatile)) {

    UseBarriersForVolatile = (_features & CPU_DMB_ATOMICS) != 0;

  }

  if (FLAG_IS_DEFAULT(UsePopCountInstruction)) {

    UsePopCountInstruction = true;

  }

#ifdef COMPILER2

  if (FLAG_IS_DEFAULT(UseMultiplyToLenIntrinsic)) {

    UseMultiplyToLenIntrinsic = true;

  }

  if (FLAG_IS_DEFAULT(UseSquareToLenIntrinsic)) {

    UseSquareToLenIntrinsic = true;

  }

  if (FLAG_IS_DEFAULT(UseMulAddIntrinsic)) {

    UseMulAddIntrinsic = true;

  }

  if (FLAG_IS_DEFAULT(UseMontgomeryMultiplyIntrinsic)) {

    UseMontgomeryMultiplyIntrinsic = true;

  }

  if (FLAG_IS_DEFAULT(UseMontgomerySquareIntrinsic)) {

    UseMontgomerySquareIntrinsic = true;

  }

  if (FLAG_IS_DEFAULT(OptoScheduling)) {

    OptoScheduling = true;

  }

#endif

}

void VM_Version::initialize() {

  ResourceMark rm;

  stub_blob = BufferBlob::create("getPsrInfo_stub", stub_size);

  if (stub_blob == NULL) {

    vm_exit_during_initialization("Unable to allocate getPsrInfo_stub");

  }

  CodeBuffer c(stub_blob);

  VM_Version_StubGenerator g(&c);

  getPsrInfo_stub = CAST_TO_FN_PTR(getPsrInfo_stub_t,

                                   g.generate_getPsrInfo());

  get_processor_features();

  UNSUPPORTED_OPTION(CriticalJNINatives);

}