3 files changed, 30 insertions, 14 deletions
diff --git a/arch/x86_64/include/x86_64/boot/boot.hpp b/arch/x86_64/include/x86_64/boot/boot.hpp
index 3a3620d..6dcd2de 100644
--- a/arch/x86_64/include/x86_64/boot/boot.hpp
+++ b/arch/x86_64/include/x86_64/boot/boot.hpp
@@ -45,26 +45,22 @@
 /* clang-format on */
 #else
 
+#include "kapi/boot.hpp"  // IWYU pragma: export
+
 #include <multiboot2/information.hpp>
 
-#include <kstd/asm_ptr>
+#include <cstddef>
 
-namespace teachos::boot::x86_64
+namespace teachos::boot
 {
 
-  extern "C"
+  struct information
   {
-    /**
-     * @brief A pointer to the multiboot 2 information structure provided by the boot loader.
-     */
-    extern kstd::asm_ptr<multiboot2::information_view> multiboot_information_pointer;
-
-    /**
-     * @brief A pointer to the VGA text mode buffer.
-     */
-    extern kstd::asm_ptr<std::pair<char, std::byte>> vga_buffer_pointer;
-  }
-}  // namespace teachos::boot::x86_64
+    multiboot2::information_view const * mbi;
+    std::size_t vga_buffer_index;
+  };
+
+}  // namespace teachos::boot
 
 #endif
 
diff --git a/arch/x86_64/include/x86_64/boot/ld.hpp b/arch/x86_64/include/x86_64/boot/ld.hpp
index 104e6ee..9af3dc8 100644
--- a/arch/x86_64/include/x86_64/boot/ld.hpp
+++ b/arch/x86_64/include/x86_64/boot/ld.hpp
@@ -61,6 +61,15 @@ namespace teachos::boot::x86_64
      * To use this symbol for its intended purpose, the address of it shall be taken.
      */
     extern std::byte _end_virtual;
+
+    /**
+     * @brief The first byte of the kernel's virtual address space.
+     *
+     * @details
+     * This symbol is defined in the kernel linker script and marks beginning of the kernel virtual address space. To
+     * use this symbol for its intended purpose, the address of it shall be taken.
+     */
+    extern std::byte TEACHOS_VMA;
   }
 }  // namespace teachos::boot::x86_64
 
diff --git a/arch/x86_64/include/x86_64/vga/text.hpp b/arch/x86_64/include/x86_64/vga/text.hpp
index d8919bf..bb593e7 100644
--- a/arch/x86_64/include/x86_64/vga/text.hpp
+++ b/arch/x86_64/include/x86_64/vga/text.hpp
@@ -4,6 +4,7 @@
 #include "kapi/cio.hpp"
 
 #include <cstdint>
+#include <span>
 #include <string_view>
 
 namespace teachos::vga::x86_64::text
@@ -100,6 +101,8 @@ namespace teachos::vga::x86_64::text
 
   struct device final : teachos::cio::output_device
   {
+    device();
+
     /**
      * @brief Clear the VGA text mode buffer.
      *
@@ -134,6 +137,8 @@ namespace teachos::vga::x86_64::text
     }
 
   private:
+    using glyph = std::pair<char, std::byte>;
+
     /**
      * @brief Move the cursor to a new line, scrolling the buffer if necessary.
      */
@@ -150,6 +155,8 @@ namespace teachos::vga::x86_64::text
      */
     auto write(std::string_view code_points, attribute attribute) -> void;
 
+    auto write(char code_point, attribute attribute) -> void;
+
     /**
      * @brief Write a string of code points followed by a newline to the VGA text buffer.
      *
@@ -160,6 +167,10 @@ namespace teachos::vga::x86_64::text
      * @see vga::text::attribute
      */
     auto writeln(std::string_view code_points, attribute attribute) -> void;
+
+    std::span<glyph> static const buffer;
+
+    std::size_t m_position{};
   };
 
 }  // namespace teachos::vga::x86_64::text