ptos/amd64: cpu: Add interrupt descriptor table

Signed-off-by: Chloe M. <chloe@mensia.org>
2026-07-11 03:08:00 +00:00
parent cf393eab7b
commit 027074d548
2 changed files with 94 additions and 0 deletions
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description: AMD64 interrupt gate management
+ * Author:      Chloe M.
+ */
+
+#include <machine/idt.h>
+#include <machine/gdt.h>
+#include <ptdef.h>
+
+static IDT_GATE Idt[256];
+ALIGN(8) IDTR Idtr = {
+    .Limit = sizeof(Idt) - 1,
+    .Offset = (UPTR)&Idt[0]
+};
+
+VOID
+MdIdtSetGate(UCHAR Vector, UPTR Offset, UCHAR Type, UCHAR Ist)
+{
+    IDT_GATE *Gate;
+
+    Gate = &Idt[Vector];
+    Gate->OffsetLow16 = Offset & 0xFFFF;
+    Gate->OffsetMid16 = (Offset >> 16) & 0xFFFF;
+    Gate->OffsetHigh32 = (Offset >> 32) & 0xFFFFFFFF;
+    Gate->Reserved = 0;
+    Gate->Zero = 0;
+    Gate->Zero1 = 0;
+    Gate->Type = Type;
+    Gate->Dpl = (Type == IDT_USER_GATE) ? 3 : 0;
+    Gate->Present = 1;
+    Gate->Ist = Ist;
+    Gate->SegmentSel = GDT_KCODE;
+}
+
+VOID
+MdIdtLoad(VOID)
+{
+    ASMV(
+        "lidt %0"
+        :
+        : "m" (Idtr)
+        : "memory"
+    );
+}