From 398d889c7409570fa3b7b7305427be0408e2c475 Mon Sep 17 00:00:00 2001
From: Alex <enderice2@users.noreply.github.com>
Date: Thu, 13 Oct 2022 09:32:26 +0300
Subject: [PATCH] Multiboot2Initializator stub

---
 Architecture/i686/MultibootInit.cpp | 43 +++++++++++++++++++++++++++++
 Architecture/i686/boot.asm          |  2 ++
 Kernel.cpp                          |  5 ++--
 3 files changed, 48 insertions(+), 2 deletions(-)
 create mode 100644 Architecture/i686/MultibootInit.cpp

diff --git a/Architecture/i686/MultibootInit.cpp b/Architecture/i686/MultibootInit.cpp
new file mode 100644
index 0000000..4712b33
--- /dev/null
+++ b/Architecture/i686/MultibootInit.cpp
@@ -0,0 +1,43 @@
+#include <types.h>
+
+EXTERNC __attribute__((no_stack_protector, section(".multiboot.text"))) void Multiboot2Initializator()
+{
+    for (int i = 0; i < 2000; i++)
+    {
+        ((unsigned int *)0xb8000)[i * 2] = ' ';
+        ((unsigned int *)0xb8000)[i * 2 + 1] = 0;
+    }
+    ((uint8_t *)0xb8000)[2 * (80) * (25) - 2] = 'W';
+    ((uint8_t *)0xb8000)[2 * (80) * (25) - 1] = 6;
+    unsigned char *SMBIOSAddress = (unsigned char *)0xF0000;
+    while ((unsigned int)(unsigned long)SMBIOSAddress < 0x100000)
+    {
+        if (SMBIOSAddress[0] == '_' &&
+            SMBIOSAddress[1] == 'S' &&
+            SMBIOSAddress[2] == 'M' &&
+            SMBIOSAddress[3] == '_')
+        {
+            unsigned char Checksum = 0;
+            int Length = SMBIOSAddress[5];
+            for (int i = 0; i < Length; i++)
+                Checksum += SMBIOSAddress[i];
+
+            if (Checksum == 0)
+                break;
+        }
+        SMBIOSAddress += 16;
+    }
+
+    if ((unsigned int)(unsigned long)SMBIOSAddress == 0x100000)
+    {
+        // No SMBIOS found
+        ((uint8_t *)0xb8000)[2 * (80) * (25) - 4] = 'S';
+        ((uint8_t *)0xb8000)[2 * (80) * (25) - 3] = 4;
+        while (1)
+            asmv("hlt");
+    }
+
+    ((uint8_t *)0xb8000)[2 * (80) * (25) - 10] = 'Y';
+    ((uint8_t *)0xb8000)[2 * (80) * (25) - 9] = 2;
+    return;
+}
diff --git a/Architecture/i686/boot.asm b/Architecture/i686/boot.asm
index 277066d..78c1d33 100644
--- a/Architecture/i686/boot.asm
+++ b/Architecture/i686/boot.asm
@@ -26,6 +26,7 @@ BOOT_PAGE_TBL1: resb 4096
 
 section .multiboot2.text
 extern x32Entry
+extern Multiboot2Initializator
 extern _kernel_start
 extern _kernel_end
 global _start
@@ -58,6 +59,7 @@ _start:
     add edi, 4
     loop .PagingLoop
 .LoopEnd:
+    call Multiboot2Initializator
     push ebx
     mov dword [BOOT_PAGE_DIR0 - KERNEL_VIRTUAL_BASE + (000 * 4)], (BOOT_PAGE_TBL0 - KERNEL_VIRTUAL_BASE + 3)
     mov dword [BOOT_PAGE_DIR0 - KERNEL_VIRTUAL_BASE + (001 * 4)], (BOOT_PAGE_TBL1 - KERNEL_VIRTUAL_BASE + 3)
diff --git a/Kernel.cpp b/Kernel.cpp
index 7b2883e..ca38fd8 100644
--- a/Kernel.cpp
+++ b/Kernel.cpp
@@ -8,6 +8,7 @@
 #include <time.hpp>
 #include <debug.h>
 #include <smp.hpp>
+#include <io.h>
 
 NEWLOCK(KernelLock);
 
@@ -42,9 +43,9 @@ EXTERNC void KPrint(const char *format, ...)
 
 EXTERNC void Entry(BootInfo *Info)
 {
-    BootClock = ReadClock();
-    trace("Hello, World!");
     InitializeMemoryManagement(Info);
+    trace("Hello, World!");
+    BootClock = ReadClock();
     bInfo = (BootInfo *)KernelAllocator.RequestPages(TO_PAGES(sizeof(BootInfo)));
     memcpy(bInfo, Info, sizeof(BootInfo));
     debug("BootInfo structure is at %p", bInfo);