set up bochs for debugging and started working on interrupts.

9 files changed, 88 insertions, 15 deletions

diff --git a/src/boot/boot.s b/src/boot/boot.s
index aba32ff..22d32f3 100644
--- a/src/boot/boot.s
+++ b/src/boot/boot.s
@@ -19,10 +19,17 @@ resb 16384
 stack_top:
 
 section .text
+
 global gdtr
 gdtr:
   dw 0
   dd 0
+
+global idtr
+idtr:
+  dw 0
+  dd 0
+
 global _start:function (_start.end - _start)
 _start:
   mov esp, stack_top
@@ -37,10 +44,17 @@ _start:
 
   call reloadSegments
 
+  extern get_idtr
+  call get_idtr
+  lidt [idtr]
+
   [bits 32]
   extern kernel_main
   call kernel_main
 
+  ; BOCHS
+  xchg bx, bx
+
 
 	cli
 .hang:	hlt
diff --git a/src/include/asm.h b/src/include/asm.h
new file mode 100644
index 0000000..97ea45a
--- /dev/null
+++ b/src/include/asm.h
@@ -0,0 +1,15 @@
+#pragma once
+#include <stdint.h>
+
+// IO
+static inline void outb(uint16_t port, uint8_t val) {
+    asm volatile("outb %0, %1" : : "a"(val), "Nd"(port) : "memory");
+}
+
+static inline uint8_t inb(uint16_t port) {
+    uint8_t ret;
+    asm volatile("inb %1, %0" : "=a"(ret) : "Nd"(port) : "memory");
+    return ret;
+}
+
+static inline void io_wait(void) { outb(0x80, 0); }
diff --git a/src/include/gdt.h b/src/include/gdt.h
index 06a0d96..8cc2542 100644
--- a/src/include/gdt.h
+++ b/src/include/gdt.h
@@ -16,11 +16,13 @@ typedef struct GDTR {
     uint32_t offset;
 } __attribute__((packed)) GDTR_t;
 
-typedef struct GDT {
-    Segment_Descriptor_t nulldesc;
-    Segment_Descriptor_t codedesc;
-    Segment_Descriptor_t datadesc;
-} __attribute__((packed)) GDT_t;
+// typedef struct GDT {
+//     Segment_Descriptor_t nulldesc;
+//     Segment_Descriptor_t codedesc;
+//     Segment_Descriptor_t datadesc;
+// } __attribute__((packed)) GDT_t;
+
+typedef Segment_Descriptor_t *GDT_t;
 
 uint16_t make_code(uint8_t priv, uint8_t dc, uint8_t rw);
 uint16_t make_data(uint8_t priv, uint8_t dc, uint8_t rw);
diff --git a/src/include/idt.h b/src/include/idt.h
new file mode 100644
index 0000000..b8413b8
--- /dev/null
+++ b/src/include/idt.h
@@ -0,0 +1,17 @@
+#pragma once
+#include <stdint.h>
+
+typedef struct Gate_Descriptor {
+    uint16_t offset_low;
+    uint16_t segment_selector;
+    uint8_t reserved;
+    uint8_t attrs;
+    uint16_t offset_high;
+} __attribute__((packed)) Gate_Descriptor_t;
+
+typedef Gate_Descriptor_t *IDT_t;
+
+Gate_Descriptor_t make_gate(uint32_t offset, uint8_t segment_selector,
+                            uint8_t attrs);
+
+void get_idtr();
diff --git a/src/kernel/gdt/gdt.c b/src/kernel/gdt.c
index 4886dc3..406b40c 100644
--- a/src/kernel/gdt/gdt.c
+++ b/src/kernel/gdt.c
@@ -1,19 +1,15 @@
 #include "gdt.h"
 #include <stdint.h>
 
-GDT_t *table = 0x0;
+GDT_t table = 0x0;
 extern GDTR_t gdtr;
 void get_gdtr() {
     uint32_t base = 0x0000;
 
-    *table = (GDT_t){
-        // NULL
-        make_descriptor(0, 0, 0),
-        // Code segment, read
-        make_descriptor(base, 0x8FFFF, make_code(0, 0, 1)),
-        // Data segment, read write
-        make_descriptor(base, 0x8FFFF, make_data(0, 0, 1)),
-    };
+    table[0] = make_descriptor(0, 0, 0);
+    table[1] = make_descriptor(base, 0x3FFFF, make_code(0, 0, 1));
+    table[2] = make_descriptor(base, 0x3FFFF, make_data(0, 0, 1));
+
     gdtr.size = sizeof(Segment_Descriptor_t) * 3 - 1;
     gdtr.offset = base;
 }
diff --git a/src/kernel/gdt/compile_flags.txt b/src/kernel/gdt/compile_flags.txt
deleted file mode 100644
index 2af49c7..0000000
--- a/src/kernel/gdt/compile_flags.txt
+++ /dev/null
@@ -1 +0,0 @@
--I../../include/
diff --git a/src/kernel/idt.c b/src/kernel/idt.c
new file mode 100644
index 0000000..f3fea4f
--- /dev/null
+++ b/src/kernel/idt.c
@@ -0,0 +1,28 @@
+#include "idt.h"
+#include "gdt.h"
+#include <stdint.h>
+
+IDT_t idt = (IDT_t)0x7fffe;
+extern GDTR_t idtr;
+
+void get_idtr() {
+    int base = 0x7fffe;
+    uint8_t code_seg = (0b1000 << 3) | 0b000;
+
+    // idtr.size = sizeof(Gate_Descriptor_t) * n - 1;
+    idtr.size = 0;
+    idtr.offset = base;
+}
+
+Gate_Descriptor_t make_gate(uint32_t offset, uint8_t segment_selector,
+                            uint8_t type) {
+    Gate_Descriptor_t ret = (Gate_Descriptor_t){
+        .offset_low = offset,
+        .reserved = 0,
+        .attrs = (0b1000 << 4) | type,
+        .offset_high = offset >> 16,
+        .segment_selector = segment_selector,
+    };
+
+    return ret;
+}
diff --git a/src/kernel/keyboard/pic.c b/src/kernel/keyboard/pic.c
new file mode 100644
index 0000000..0c81629
--- /dev/null
+++ b/src/kernel/keyboard/pic.c
@@ -0,0 +1 @@
+#include "asm.h"
diff --git a/src/utils/compile_flags.txt b/src/utils/compile_flags.txt
new file mode 100644
index 0000000..b02b210
--- /dev/null
+++ b/src/utils/compile_flags.txt
@@ -0,0 +1 @@
+-I../include