1 files changed, 54 insertions, 0 deletions
diff --git a/kernel/boot/gdt/gdt.cc b/kernel/boot/gdt/gdt.cc
new file mode 100644
index 0000000..e86638a
--- /dev/null
+++ b/kernel/boot/gdt/gdt.cc
@@ -0,0 +1,54 @@
+/*
+ * bubbl
+ * Copyright (C) 2024-2025  Raghuram Subramani <raghus2247@gmail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <boot/gdt.h>
+#include <kernel/io.h>
+#include <stdint.h>
+
+namespace GDT
+{
+
+entry_t entries[] = {
+  /* NULL Descriptor */
+  GDT_ENTRY(0, 0, 0, 0),
+
+  /* Kernel Mode Code Segment */
+  GDT_ENTRY(0, 0xfffff, KERNEL_CODE_SEGMENT_ACCESS_FLAGS, FLAGS),
+
+  /* Kernel Mode Data Segment */
+  GDT_ENTRY(0, 0xfffff, KERNEL_DATA_SEGMENT_ACCESS_FLAGS, FLAGS),
+
+  /* User Mode Code Segment */
+  // GDT_ENTRY(0, 0xfffff, USER_CODE_SEGMENT_ACCESS_FLAGS, FLAGS),
+
+  /* User Mode Data Segment */
+  // GDT_ENTRY(0, 0xfffff, USER_DATA_SEGMENT_ACCESS_FLAGS, FLAGS)
+
+  /* TODO: TSS? */
+  /* TODO: LDT? */
+};
+
+descriptor_t descriptor = { sizeof(entries) - 1, entries };
+
+void
+load(void)
+{
+  _GDT_flush(&descriptor);
+}
+
+}