Interrupts + basic keyboard driver

1 files changed, 27 insertions, 0 deletions

diff --git a/src/kernel/tables/idt.c b/src/kernel/tables/idt.c
new file mode 100644
index 0000000..01a6776
--- /dev/null
+++ b/src/kernel/tables/idt.c
@@ -0,0 +1,27 @@
+#include "idt.h"
+#include "gdt.h"
+#include "isr.h"
+#include <stdint.h>
+
+__attribute__((aligned(0x10))) static Gate_Descriptor_t idt[256];
+extern GDTR_t idtr;
+extern void *isr_stub_table;
+
+void get_idtr() {
+    idtr.offset = (uintptr_t)&idt[0];
+    idtr.size = sizeof(Gate_Descriptor_t) * 256 - 1;
+    for (uint8_t vec = 0; vec < 32; vec++) {
+        make_gate(((void **)(isr_stub_table))[vec], 0x8E, vec);
+    }
+    make_gate(wrap_keyboard_handler, 0x8E, 0x21);
+}
+
+void make_gate(void *isr, uint8_t attrs, uint8_t vec) {
+    Gate_Descriptor_t *descriptor = &idt[vec];
+
+    descriptor->offset_low = (uint32_t)isr & 0xFFFF;
+    descriptor->attrs = (0b1000 << 4) | attrs;
+    descriptor->offset_high = (uint32_t)isr >> 16;
+    descriptor->segment_selector = 0x08;
+    descriptor->reserved = 0;
+}