/*

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

 * Copyright (c) 2014, 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.

 *

 */

#ifndef CPU_AARCH64_VM_VERSION_AARCH64_HPP

#define CPU_AARCH64_VM_VERSION_AARCH64_HPP

#include "runtime/globals_extension.hpp"

#include "runtime/vm_version.hpp"

#include "utilities/sizes.hpp"

class VM_Version : public Abstract_VM_Version {

  friend class JVMCIVMStructs;

protected:

  static int _cpu;

  static int _model;

  static int _model2;

  static int _variant;

  static int _revision;

  static int _stepping;

  static bool _dcpop;

  struct PsrInfo {

    uint32_t dczid_el0;

    uint32_t ctr_el0;

  };

  static PsrInfo _psr_info;

  static void get_processor_features();

public:

  // Initialization

  static void initialize();

  // Asserts

  static void assert_is_initialized() {

  }

  static bool expensive_load(int ld_size, int scale) {

    if (cpu_family() == CPU_ARM) {

      // Half-word load with index shift by 1 (aka scale is 2) has

      // extra cycle latency, e.g. ldrsh w0, [x1,w2,sxtw #1].

      if (ld_size == 2 && scale == 2) {

        return true;

      }

    }

    return false;

  }

  // The CPU implementer codes can be found in

  // ARM Architecture Reference Manual ARMv8, for ARMv8-A architecture profile

  // https://developer.arm.com/docs/ddi0487/latest

  enum Family {

    CPU_AMPERE    = 0xC0,

    CPU_ARM       = 'A',

    CPU_BROADCOM  = 'B',

    CPU_CAVIUM    = 'C',

    CPU_DEC       = 'D',

    CPU_HISILICON = 'H',

    CPU_INFINEON  = 'I',

    CPU_MOTOROLA  = 'M',

    CPU_NVIDIA    = 'N',

    CPU_AMCC      = 'P',

    CPU_QUALCOM   = 'Q',

    CPU_MARVELL   = 'V',

    CPU_INTEL     = 'i',

  };

  enum Feature_Flag {

    CPU_FP           = (1<<0),

    CPU_ASIMD        = (1<<1),

    CPU_EVTSTRM      = (1<<2),

    CPU_AES          = (1<<3),

    CPU_PMULL        = (1<<4),

    CPU_SHA1         = (1<<5),

    CPU_SHA2         = (1<<6),

    CPU_CRC32        = (1<<7),

    CPU_LSE          = (1<<8),

    CPU_STXR_PREFETCH= (1 << 29),

    CPU_A53MAC       = (1 << 30),

    CPU_DMB_ATOMICS  = (1 << 31),

  };

  static int cpu_family()                     { return _cpu; }

  static int cpu_model()                      { return _model; }

  static int cpu_model2()                     { return _model2; }

  static int cpu_variant()                    { return _variant; }

  static int cpu_revision()                   { return _revision; }

  static bool supports_dcpop()                { return _dcpop; }

  static ByteSize dczid_el0_offset() { return byte_offset_of(PsrInfo, dczid_el0); }

  static ByteSize ctr_el0_offset()   { return byte_offset_of(PsrInfo, ctr_el0); }

  static bool is_zva_enabled() {

    // Check the DZP bit (bit 4) of dczid_el0 is zero

    // and block size (bit 0~3) is not zero.

    return ((_psr_info.dczid_el0 & 0x10) == 0 &&

            (_psr_info.dczid_el0 & 0xf) != 0);

  }

  static int zva_length() {

    assert(is_zva_enabled(), "ZVA not available");

    return 4 << (_psr_info.dczid_el0 & 0xf);

  }

  static int icache_line_size() {

    return (1 << (_psr_info.ctr_el0 & 0x0f)) * 4;

  }

  static int dcache_line_size() {

    return (1 << ((_psr_info.ctr_el0 >> 16) & 0x0f)) * 4;

  }

  static bool supports_fast_class_init_checks() { return true; }

};

#endif // CPU_AARCH64_VM_VERSION_AARCH64_HPP