From b1abb2f5a2e5bf92100b06d5049a2c33f0caf4f6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nicolas=20Hord=C3=A9?= <nicolas@palon.fr>
Date: Sat, 1 Sep 2018 22:58:05 +0200
Subject: [PATCH] feat: gestion chargement d'une nouvelle GDT - non fonctionnel

---
 lib/gdt.c        | 36 +++++++++++++++++++++++++++++++++++-
 lib/interrupts.c | 10 +++++++---
 system/system.c  |  9 ++++++++-
 3 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/lib/gdt.c b/lib/gdt.c
index 620dec3..2b35d2d 100755
--- a/lib/gdt.c
+++ b/lib/gdt.c
@@ -2,13 +2,47 @@
 #include "asm.h"
 #include "types.h"
 
+#define SIZEGDT		0x4	/* nombre de descripteurs */
+
+#define BASEGDT		0x00000800	/* addr de la GDT */
+
+ /* registre gdt */
+static struct gdtr gdtreg;
+
+/* table de GDT */
+static gdtdes gdt[SIZEGDT];
+
 /*******************************************************************************/
 
 /* Initialise la GDT */
 
 void initgdt()
 {
-	
+	makegdtdes(0x0, 0x00000, 0x00, 0x00, &gdt[0]);
+	makegdtdes(0x0, 0xFFFFF, 0x9B, 0x0D, &gdt[1]);	/* code */
+	makegdtdes(0x0, 0xFFFFF, 0x93, 0x0D, &gdt[2]);	/* data */
+	makegdtdes(0x0, 0x00000, 0x97, 0x0D, &gdt[3]);   /* pile */
+	/* initialise le registre gdt */
+	gdtreg.limite = SIZEGDT * 8;
+	gdtreg.base = BASEGDT;
+	/* recopie de la GDT a son adresse */
+	memcpy(&gdt, (u8 *) gdtreg.base, gdtreg.limite, 1);
+	/* chargement du registre GDT */
+	lgdt(&gdtreg);
+	/* initialisation des segments */
+	asm("   movw $0x10, %ax	\n \
+            movw %ax, %ds	\n \
+            movw %ax, %es	\n \
+            movw %ax, %fs	\n \
+            movw %ax, %gs   \n \
+            movl 0x0C(%esp), %eax \n \
+            movw $0x18, %ax \n \
+            movw %ax, %ss \n \
+            movl $0x20000, %esp \n \
+            pushl %eax \n \
+            ljmp $0x08, $raz	\n \
+            raz:		\n \
+            ret\n");
 }
 
 /*******************************************************************************/
diff --git a/lib/interrupts.c b/lib/interrupts.c
index b567c15..d98435c 100755
--- a/lib/interrupts.c
+++ b/lib/interrupts.c
@@ -4,6 +4,10 @@
 #include "memory.h"
 #include "video.h"
 
+#define SIZEIDT		256	/* nombre de descripteurs */
+
+#define BASEIDT		0x00000000	/* addr de la IDT */
+
  /* registre idt */
 static struct idtr idtreg;
 
@@ -535,12 +539,12 @@ void initidt(void)
 	putidt((u32) irq13, 0x20, INTGATE, 101);
 	putidt((u32) irq14, 0x20, INTGATE, 102);
 	putidt((u32) irq15, 0x20, INTGATE, 103);
-	for (i = 104; i <= 255; i++) {
+	for (i = 104; i < SIZEIDT; i++) {
 		putidt((u32) interruption, 0x20, TRAPGATE, i);
 	}
 	/* initialise le registre idt */
-	idtreg.limite = 256 * 8;
-	idtreg.base = 0x0000000;
+	idtreg.limite = SIZEIDT * 8;
+	idtreg.base = BASEIDT;
 	/* recopie de la IDT a son adresse */
 	memcpy(&idt, (u8 *) idtreg.base, idtreg.limite, 1);
 	/* chargement du registre IDTR */
diff --git a/system/system.c b/system/system.c
index bd145dc..b7eb961 100755
--- a/system/system.c
+++ b/system/system.c
@@ -46,7 +46,14 @@ int main(void)
 	print("\033[2J\000");
 	printf(ansilogo);
 
-	print("\033[37m\033[0m -Initilisation des interruptions\000");
+	print("\033[37m\033[0m -Chargement noyaux\000");
+    ok();
+
+	print("\033[37m\033[0m -Initilisation de la memoire (GDT)\000");
+    initgdt();
+	ok();
+
+	print("\033[37m\033[0m -Initilisation des interruptions (IDT/PIC)\000");
 	initidt();
 	initpic();
 	sti();