Kernel/Net: Move Realtek network adapters code to a separate directory

Kernel/Net/Realtek/RTL8139NetworkAdapter.h

@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/OwnPtr.h>
+#include <Kernel/Arch/x86/IO.h>
+#include <Kernel/Bus/PCI/Access.h>
+#include <Kernel/Bus/PCI/Device.h>
+#include <Kernel/Interrupts/IRQHandler.h>
+#include <Kernel/Net/NetworkAdapter.h>
+#include <Kernel/Random.h>
+
+namespace Kernel {
+
+#define RTL8139_TX_BUFFER_COUNT 4
+
+class RTL8139NetworkAdapter final : public NetworkAdapter
+    , public PCI::Device
+    , public IRQHandler {
+public:
+    static RefPtr<RTL8139NetworkAdapter> try_to_initialize(PCI::DeviceIdentifier const&);
+
+    virtual ~RTL8139NetworkAdapter() override;
+
+    virtual void send_raw(ReadonlyBytes) override;
+    virtual bool link_up() override { return m_link_up; }
+    virtual i32 link_speed() override;
+    virtual bool link_full_duplex() override;
+
+    virtual StringView purpose() const override { return class_name(); }
+
+private:
+    RTL8139NetworkAdapter(PCI::Address, u8 irq, NonnullOwnPtr<KString>);
+    virtual bool handle_irq(const RegisterState&) override;
+    virtual StringView class_name() const override { return "RTL8139NetworkAdapter"sv; }
+
+    void reset();
+    void read_mac_address();
+
+    void receive();
+
+    void out8(u16 address, u8 data);
+    void out16(u16 address, u16 data);
+    void out32(u16 address, u32 data);
+    u8 in8(u16 address);
+    u16 in16(u16 address);
+    u32 in32(u16 address);
+
+    IOAddress m_io_base;
+    u8 m_interrupt_line { 0 };
+    OwnPtr<Memory::Region> m_rx_buffer;
+    u16 m_rx_buffer_offset { 0 };
+    Vector<OwnPtr<Memory::Region>> m_tx_buffers;
+    u8 m_tx_next_buffer { 0 };
+    OwnPtr<Memory::Region> m_packet_buffer;
+    bool m_link_up { false };
+    EntropySource m_entropy_source;
+};
+}