From fb1a1bc213abaf3eb82fad254927e8880f4ae01e Mon Sep 17 00:00:00 2001
From: 0x35c <unai64@orange.fr>
Date: Tue, 3 Dec 2024 10:41:39 +0100
Subject: [PATCH] wip: enable vbe

---
 Makefile        |  6 ++---
 config/grub.cfg |  9 ++++---
 src/boot.s      | 30 +++++++--------------
 src/kernel.c    | 70 -------------------------------------------------
 4 files changed, 19 insertions(+), 96 deletions(-)

diff --git a/Makefile b/Makefile
index cd9412f..7826d70 100644
--- a/Makefile
+++ b/Makefile
@@ -31,7 +31,7 @@ $(NAME): $(OBJ)
 	$(LD) $(LDFLAGS) -o build/$(NAME).bin $(OBJ) $(LIBS)
 
 run: $(NAME)
-	qemu-system-i386 -kernel build/$(NAME).bin
+	qemu-system-i386 -kernel build/$(NAME).bin -vga std
 
 iso: $(NAME)
 	mkdir -p isodir/boot/grub
@@ -41,10 +41,10 @@ iso: $(NAME)
 	rm -rf isodir
 
 run-iso: iso
-	qemu-system-i386 -cdrom build/$(NAME).iso
+	qemu-system-i386 -cdrom build/$(NAME).iso -vga std
 
 debug: iso
-	qemu-system-i386 -s -S build/$(NAME).iso
+	qemu-system-i386 -s -S build/$(NAME).iso -vga std
 
 clean:
 	make -C libbozo clean
diff --git a/config/grub.cfg b/config/grub.cfg
index c613661..92f0601 100644
--- a/config/grub.cfg
+++ b/config/grub.cfg
@@ -1,3 +1,6 @@
-menuentry "bozos" {
-	multiboot /boot/bozOS.bin
-}
\ No newline at end of file
+set gfxmode=1024x768x32
+set gfxpayload=keep
+menuentry "bozOS" {
+    multiboot /boot/bozOS.bin
+    boot
+}
diff --git a/src/boot.s b/src/boot.s
index 24b0979..9b79334 100644
--- a/src/boot.s
+++ b/src/boot.s
@@ -1,27 +1,17 @@
 # Declare constants for the multiboot header.
-.set ALIGN,    1<<0             # align loaded modules on page boundaries
-.set MEMINFO,  1<<1             # provide memory map
-.set MAGIC,    0xE85250D6       # 'magic number' lets bootloader find the header
-.set ARCHITECTURE, 0
+.set ALIGN,	1<<0             # align loaded modules on page boundaries
+.set MEMINFO,	1<<1             # provide memory map
+.set VIDEOMODE,	1<<2             # provide memory map
+.set FLAGS,	ALIGN | MEMINFO | VIDEOMODE  # this is the Multiboot 'flag' field
+.set MAGIC,	0x1BADB002       # 'magic number' lets bootloader find the header
+.set CHECKSUM,	-(MAGIC + FLAGS) # checksum of above, to prove we are multiboot
 
 # Declare a multiboot header that marks the program as a kernel.
 .section .multiboot.data, "aw"
-header_start:
-	# HEADER
-	.long MAGIC
-	.long ARCHITECTURE
-	.long header_end - header_start
-	.long 0x100000000 - (MAGIC + (header_end - header_start))
-
-	#TAGS:
-
-
-	# END TAG
-	.align 8
-	.int 0		# type
-	.int 0		# flag
-	.long 8		# size
-header_end:
+.align 4
+.long MAGIC
+.long FLAGS
+.long CHECKSUM
 
 # Allocate the initial stack.
 .section .bootstrap_stack, "aw", @nobits
diff --git a/src/kernel.c b/src/kernel.c
index 5800678..5ee48d3 100644
--- a/src/kernel.c
+++ b/src/kernel.c
@@ -26,50 +26,6 @@
 #error "This tutorial needs to be compiled with a ix86-elf compiler"
 #endif
 
-/* Par contre je me dois d'être honnête avec toi, j'ai passé un très bon moment
- * hier soir c'était vraiment posé et tout mais j'ai pas trop ressenti de
- * feeling qui me donnerait envie de continuer dans une relation "couple" sur le
- * long terme. Je sais pas trop comment le dire sans que ça te blesse, c'est pas
- * personnel ou quoi c'est cool quand on parle et tout mais juste je ne pense
- * pas pouvoir faire marcher une relation comme celle là :( */
-/* Voilà je voulais juste te le dire pour pas que tu te mettes quelque chose en
- * tête qui n'arrivera pas, je trouve ça plus correct */
-
-static void set_mem_size(multiboot_info_t *mbd, uint32_t magic)
-{
-	/* Make sure the magic number matches for memory mapping */
-	if (magic != MULTIBOOT_BOOTLOADER_MAGIC)
-		kpanic("invalid magic number!");
-
-	/* Check bit 6 to see if we have a valid memory map */
-	if (!(mbd->flags >> 6 & 0x1))
-		kpanic("invalid memory map given by GRUB bootloader");
-
-	/* Loop through the memory map and display the values */
-	for (uint32_t i = 0; i < mbd->mmap_length;
-	     i += sizeof(multiboot_memory_map_t)) {
-		multiboot_memory_map_t *mmmt =
-		    (multiboot_memory_map_t *)(mbd->mmap_addr + i);
-		/* if (mmmt->type == MULTIBOOT_MEMORY_AVAILABLE) */
-		/* mem_size += mmmt->len; */
-	}
-}
-
-extern uint32_t boot_page_table1;
-
-void get_kernel_page_used(void)
-{
-	uint32_t *boot_pt = &boot_page_table1;
-	size_t i = 0;
-	size_t used_pages = 0;
-	for (; i < 1024; i++) {
-		if ((boot_pt[i] != 0) && (boot_pt[i] != (i << 12))) {
-			used_pages++;
-		}
-	}
-	kprintf("page used: %d/%d\n", used_pages, PT_SIZE);
-}
-
 void kernel_main(multiboot_info_t *mbd, uint32_t magic)
 {
 	terminal_initialize();
@@ -81,31 +37,5 @@ void kernel_main(multiboot_info_t *mbd, uint32_t magic)
 	        "I see no way to confuse an array of 256 seg:off pairs with a "
 	        "complex 8*unknown quantity -byte descriptor table. -- Troy "
 	        "Martin 03:50, 22 March 2009 (UTC)\n");
-	// PRINT_PTR(alloc_frame());
-	if (false) {
-		void *start = alloc_pages(1);
-		int *ptr;
-		uint32_t i;
-		for (i = 1; (ptr = alloc_pages(PAGE_SIZE)); i++) {
-			memset(ptr, i % 256, PAGE_SIZE);
-			*ptr = i;
-			if (i == 4096 && 0)
-				break;
-		}
-		PRINT_UINT(i); // 32573
-		for (uint32_t j = 1; j < i - 1; j++) {
-			ptr = start + j * PAGE_SIZE;
-			for (uint32_t k = sizeof(*ptr);
-			     k < PAGE_SIZE - sizeof(*ptr); k++)
-				if (((uint8_t *)ptr)[k] != (j % 256))
-					kprintf("cringe %u != %u\n",
-					        ((uint8_t *)ptr)[k], j % 256);
-		}
-
-	} else {
-		while (vmalloc(10))
-			;
-	}
-	/* vmalloc(10); */
 	shell_init();
 }