From 2838108c6ec2072258f10c75597318eb00c75a9c Mon Sep 17 00:00:00 2001
From: Tyler McGurrin <mcgurrintyler@gmail.com>
Date: Thu, 5 Jun 2025 20:41:38 -0400
Subject: [PATCH] Memory Paging Stuff

---
 src/kernel/arch/i686/util.h   |  8 ++++----
 src/kernel/core/memory/page.c | 31 ++++++++++++++++++++++++++++++-
 src/kernel/core/memory/page.h |  4 +++-
 src/kernel/dri/cmos.c         |  6 ++++++
 src/kernel/dri/cmos.h         |  1 +
 src/kernel/main.c             | 18 ++++++------------
 src/libs/version.h            |  2 +-
 7 files changed, 51 insertions(+), 19 deletions(-)

diff --git a/src/kernel/arch/i686/util.h b/src/kernel/arch/i686/util.h
index 80bd628..1d33184 100644
--- a/src/kernel/arch/i686/util.h
+++ b/src/kernel/arch/i686/util.h
@@ -8,7 +8,7 @@
 #include <stdint.h>
 
 void __attribute__((cdecl)) Reboot();
-void __attribute__((cdecl)) Read_CR0();
-void __attribute__((cdecl)) Write_CR0(uint8_t value);
-void __attribute__((cdecl)) Read_CR3();
-void __attribute__((cdecl)) Write_CR3(uint8_t value);
+unsigned long __attribute__((cdecl)) Read_CR0();
+void __attribute__((cdecl)) Write_CR0(unsigned long value);
+unsigned long* __attribute__((cdecl)) Read_CR3();
+void __attribute__((cdecl)) Write_CR3(unsigned long* value);
diff --git a/src/kernel/core/memory/page.c b/src/kernel/core/memory/page.c
index 0fe01a0..7474d7c 100644
--- a/src/kernel/core/memory/page.c
+++ b/src/kernel/core/memory/page.c
@@ -5,5 +5,34 @@
 \*----------------*/
 #include "page.h"
 
+#include <stdio.h>
+#include <stdint.h>
+#include <dri/serial.h>
+#include <arch/i686/util.h>
+
+extern uint16_t DEBUG_COM_PORT;
+
 unsigned long* Page_Directory = (unsigned long*) 0x9c000;
-unsigned long* Page_Table = (unsigned long*) 0x9d000
+unsigned long* Page_Table = (unsigned long*) 0x9d000;
+
+void Memory_Page_Init()
+{
+    unsigned long address = 0;
+    unsigned int i;
+
+    Serial_Printf(DEBUG_COM_PORT, "MEMORY:> Mapping First 4MB of Memory.\n");
+    for(i=0; i<1024; i++) {
+    Page_Table[i] = address | 3;
+    address = address + 4096; // 4096 = 4kb
+    }
+    Serial_Printf(DEBUG_COM_PORT, "MEMORY:> Inititalizing Page Directory and Table.\n");
+
+    // fill the first entry of the page directory
+    // Page_Directory[0] = Page_Table; 
+    Page_Directory[0] = Page_Directory[0] | 3; // attribute set to: supervisor level, read/write
+    for(i=1; i<1024; i++) {
+    Page_Directory[i] = 0 | 2; // attribute set to: supervisor level, read/write
+    }
+    Write_CR3(Page_Directory);
+    Write_CR0(Read_CR0() | 0x80000000); // set the paging bit in CR0 to 1
+}
\ No newline at end of file
diff --git a/src/kernel/core/memory/page.h b/src/kernel/core/memory/page.h
index afc031f..736dabe 100644
--- a/src/kernel/core/memory/page.h
+++ b/src/kernel/core/memory/page.h
@@ -3,4 +3,6 @@
 |Copyright (C) 2024|
 |Tyler McGurrin    |
 \*----------------*/
-#pragma once
\ No newline at end of file
+#pragma once
+
+void Memory_Page_Init();
\ No newline at end of file
diff --git a/src/kernel/dri/cmos.c b/src/kernel/dri/cmos.c
index aa434b8..e237ea5 100644
--- a/src/kernel/dri/cmos.c
+++ b/src/kernel/dri/cmos.c
@@ -73,4 +73,10 @@ int Slave_FDD_Detect()
         i++;
     }
     return FDDType;
+}
+
+int uptime;
+void CPU_Timer()
+{
+    uptime++;
 }
\ No newline at end of file
diff --git a/src/kernel/dri/cmos.h b/src/kernel/dri/cmos.h
index 2d7e89b..99ecc0c 100644
--- a/src/kernel/dri/cmos.h
+++ b/src/kernel/dri/cmos.h
@@ -8,6 +8,7 @@
 #include <stdint.h>
 
 void CMOS_RTC_Handler();
+void CPU_Timer();
 int Master_FDD_Detect();
 int Slave_FDD_Detect();
 uint8_t Read_CMOS(uint8_t Register);
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 336d8f9..7a9ba36 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -16,27 +16,17 @@
 #include <dri/disk/floppy.h>
 #include <dri/disk/ata.h>
 #include <core/hal/hal.h>
+#include <core/memory/page.h>
 #include <util/param.h>
 #include <util/util.h>
 #include "../libs/version.h"
 #include "../libs/boot/bootparams.h"
 
-#define PS2_KEYBOARD_PORT 0x60
-
 extern uint8_t __bss_start;
 extern uint8_t __end;
 
 uint16_t DEBUG_COM_PORT = COM1_PORT;
 
-int uptime;
-void timer(Registers* regs)
-{
-    uptime++;
-    // printf("%d", uptime);
-    // movecursorpos(8,14);
-}
-
-
 void __attribute__((section(".entry"))) start(BootParams* bootParams) {
 
     // print logo
@@ -53,7 +43,7 @@ void __attribute__((section(".entry"))) start(BootParams* bootParams) {
 
     // Register IRQs
     printf("Registering IRQs...");
-    IRQ_RegisterHandler(0, timer);
+    IRQ_RegisterHandler(0, CPU_Timer);
     IRQ_RegisterHandler(1, Keyboard_Handler);
     IRQ_RegisterHandler(4, COM1_Serial_Handler);
     IRQ_RegisterHandler(6, Floppy_Handler);
@@ -67,6 +57,10 @@ void __attribute__((section(".entry"))) start(BootParams* bootParams) {
     // Floppy_Init(); // This should always be last; its slow as fuck
     printf("Done!\n");
 
+    // unsure why this is not working, will look into it later...
+    printf("Initializing Memory Paging...");
+    // Memory_Page_Init();
+    printf("Done!\n");
 
 
 
diff --git a/src/libs/version.h b/src/libs/version.h
index 4db63ec..89c7b44 100644
--- a/src/libs/version.h
+++ b/src/libs/version.h
@@ -6,5 +6,5 @@
 #pragma once
 
 #define LOGO "    _   _____    _   __________________\n   / | / /   |  / | / /  _/_  __/ ____/\n  /  |/ / /| | /  |/ // /  / / / __/   \n / /|  / ___ |/ /|  // /  / / / /___   \n/_/ |_/_/  |_/_/ |_/___/ /_/ /_____/   \n"
-#define VERSION "RD-00035"
+#define VERSION "RD-00036"
 #define BOOTLOGO "    _   ______  ____  ____ ______\n   / | / / __ )/ __ \\/ __ /_  __/\n  /  |/ / __  / / / / / / // /   \n / /|  / /_/ / /_/ / /_/ // /    \n/_/ |_/_____/\\____/\\____//_/     \n"