text: /*
   * Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
   *
   * SPDX-License-Identifier: BSD-2-Clause
   */
  
  #pragma once
  
  #include <AK/Function.h>
  #include <AK/String.h>
  #include <AK/Types.h>
  #include <AK/Vector.h>
  #include <Kernel/Debug.h>
  
  namespace Kernel {
  
  #define PCI_VENDOR_ID 0x00            // word
  #define PCI_DEVICE_ID 0x02            // word
  #define PCI_COMMAND 0x04              // word
  #define PCI_STATUS 0x06               // word
  #define PCI_REVISION_ID 0x08          // byte
  #define PCI_PROG_IF 0x09              // byte
  #define PCI_SUBCLASS 0x0a             // byte
  #define PCI_CLASS 0x0b                // byte
  #define PCI_CACHE_LINE_SIZE 0x0c      // byte
  #define PCI_LATENCY_TIMER 0x0d        // byte
  #define PCI_HEADER_TYPE 0x0e          // byte
  #define PCI_BIST 0x0f                 // byte
  #define PCI_BAR0 0x10                 // u32
  #define PCI_BAR1 0x14                 // u32
  #define PCI_BAR2 0x18                 // u32
  #define PCI_BAR3 0x1C                 // u32
  #define PCI_BAR4 0x20                 // u32
  #define PCI_BAR5 0x24                 // u32
  #define PCI_SUBSYSTEM_ID 0x2C         // u16
  #define PCI_SUBSYSTEM_VENDOR_ID 0x2E  // u16
  #define PCI_CAPABILITIES_POINTER 0x34 // u8
  #define PCI_INTERRUPT_LINE 0x3C       // byte
  #define PCI_SECONDARY_BUS 0x19        // byte
  #define PCI_HEADER_TYPE_DEVICE 0
  #define PCI_HEADER_TYPE_BRIDGE 1
  #define PCI_TYPE_BRIDGE 0x0604
  #define PCI_ADDRESS_PORT 0xCF8
  #define PCI_VALUE_PORT 0xCFC
  #define PCI_NONE 0xFFFF
  #define PCI_MAX_DEVICES_PER_BUS 32
  #define PCI_MAX_BUSES 256
  #define PCI_MAX_FUNCTIONS_PER_DEVICE 8
  
  #define PCI_CAPABILITY_NULL 0x0
  #define PCI_CAPABILITY_MSI 0x5
  #define PCI_CAPABILITY_VENDOR_SPECIFIC 0x9
  #define PCI_CAPABILITY_MSIX 0x11
  
  namespace PCI {
  struct ID {
      u16 vendor_id { 0 };
      u16 device_id { 0 };
  
      bool is_null() const { return !vendor_id && !device_id; }
  
      bool operator==(const ID& other) const
      {
          return vendor_id == other.vendor_id && device_id == other.device_id;
      }
      bool operator!=(const ID& other) const
      {
          return vendor_id != other.vendor_id || device_id != other.device_id;
      }
  };
  
  struct Address {
  public:
      Address() = default;
      Address(u16 seg)
          : m_seg(seg)
          , m_bus(0)
          , m_device(0)
          , m_function(0)
      {
      }
      Address(u16 seg, u8 bus, u8 device, u8 function)
          : m_seg(seg)
          , m_bus(bus)
          , m_device(device)
          , m_function(function)
      {
      }
  
      Address(const Address& address)
          : m_seg(address.seg())
          , m_bus(address.bus())
          , m_device(address.device())
          , m_function(address.function())
      {
      }
  
      bool is_null() const { return !m_bus && !m_device && !m_function; }
      operator bool() const { return !is_null(); }
  
      // Disable default implementations that would use surprising integer promotion.
      bool operator==(const Address&) const = delete;
      bool operator<=(const Address&) const = delete;
      bool operator>=(const Address&) const = delete;
      bool operator<(const Address&) const = delete;
      bool operator>(const Address&) const = delete;
  
      u16 seg() const { return m_seg; }
      u8 bus() const { return m_bus; }
      u8 device() const { return m_device; }
      u8 function() const { return m_function; }
  
      u32 io_address_for_field(u8 field) const
      {
          return 0x80000000u | (m_bus << 16u) | (m_device << 11u) | (m_function << 8u) | (field & 0xfc);
      }
  
  protected:
      u32 m_seg { 0 };
      u8 m_bus { 0 };
      u8 m_device { 0 };
      u8 m_function { 0 };
  };
  
  struct ChangeableAddress : public Address {
      ChangeableAddress()
          : Address(0)
      {
      }
      explicit ChangeableAddress(u16 seg)
          : Address(seg)
      {
      }
      ChangeableAddress(u16 seg, u8 bus, u8 device, u8 function)
          : Address(seg, bus, device, function)
      {
      }
      void set_seg(u16 seg) { m_seg = seg; }
      void set_bus(u8 bus) { m_bus = bus; }
      void set_device(u8 device) { m_device = device; }
      void set_function(u8 function) { m_function = function; }
      bool operator==(const Address& address)
      {
          if (m_seg == address.seg() && m_bus == address.bus() && m_device == address.device() && m_function == address.function())
              return true;
          else
              return false;
      }
      const ChangeableAddress& operator=(const Address& address)
      {
          set_seg(address.seg());
          set_bus(address.bus());
          set_device(address.device());
          set_function(address.function());
          return *this;
      }
  };
  
  class Capability {
  public:
      Capability(const Address& address, u8 id, u8 ptr)
          : m_address(address)
          , m_id(id)
          , m_ptr(ptr)
      {
      }
  
      u8 id() const { return m_id; }
  
      u8 read8(u32) const;
      u16 read16(u32) const;
      u32 read32(u32) const;
      void write8(u32, u8);
      void write16(u32, u16);
      void write32(u32, u32);
  
  private:
      Address m_address;
      const u8 m_id;
      const u8 m_ptr;
  };
  
  class PhysicalID {
  public:
      PhysicalID(Address address, ID id, Vector<Capability> capabilities)
          : m_address(address)
          , m_id(id)
          , m_capabilities(capabilities)
      {
          if constexpr (PCI_DEBUG) {
              for (auto capability : capabilities)
                  dbgln("{} has capability {}", address, capability.id());
          }
      }
  
      Vector<Capability> capabilities() const { return m_capabilities; }
      const ID& id() const { return m_id; }
      const Address& address() const { return m_address; }
  
  private:
      Address m_address;
      ID m_id;
      Vector<Capability> m_capabilities;
  };
  
  ID get_id(PCI::Address);
  bool is_io_space_enabled(Address);
  void enumerate(Function<void(Address, ID)> callback);
  void enable_interrupt_line(Address);
  void disable_interrupt_line(Address);
  u8 get_interrupt_line(Address);
  void raw_access(Address, u32, size_t, u32);
  u32 get_BAR0(Address);
  u32 get_BAR1(Address);
  u32 get_BAR2(Address);
  u32 get_BAR3(Address);
  u32 get_BAR4(Address);
  u32 get_BAR5(Address);
  u32 get_BAR(Address address, u8 bar);
  u8 get_revision_id(Address);
  u8 get_programming_interface(Address);
  u8 get_subclass(Address);
  u8 get_class(Address);
  u16 get_subsystem_id(Address);
  u16 get_subsystem_vendor_id(Address);
  size_t get_BAR_space_size(Address, u8);
  Optional<u8> get_capabilities_pointer(Address);
  Vector<Capability> get_capabilities(Address);
  void enable_bus_mastering(Address);
  void disable_bus_mastering(Address);
  void enable_io_space(Address);
  void disable_io_space(Address);
  void enable_memory_space(Address);
  void disable_memory_space(Address);
  PhysicalID get_physical_id(Address address);
  
  class Access;
  class MMIOAccess;
  class WindowedMMIOAccess;
  class IOAccess;
  class MMIOSegment;
  class DeviceController;
  class Device;
  
  }
  
  }
  
  template<>
  struct AK::Formatter<Kernel::PCI::Address> : Formatter<FormatString> {
      void format(FormatBuilder& builder, Kernel::PCI::Address value)
      {
          return Formatter<FormatString>::format(
              builder,
              "PCI [{:04x}:{:02x}:{:02x}:{:02x}]", value.seg(), value.bus(), value.device(), value.function());
      }
  };
  
  template<>
  struct AK::Formatter<Kernel::PCI::ID> : Formatter<FormatString> {
      void format(FormatBuilder& builder, Kernel::PCI::ID value)
      {
          return Formatter<FormatString>::format(
              builder,
              "PCI::ID [{:04x}:{:04x}]", value.vendor_id, value.device_id);
      }
  };
  