6 files changed, 127 insertions, 29 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index df8ece7..03138fa 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -11,6 +11,7 @@ OBJS = \
 	src/cpu/irq_stub.o \
 	src/cpu/pic.o \
 	src/devices/keyboard.o \
+	src/libk/list.o \
 	src/libk/math.o \
 	src/libk/stdio.o \
 	src/libk/string.o \
diff --git a/kernel/include/libk/list.h b/kernel/include/libk/list.h
new file mode 100644
index 0000000..f6a97f8
--- /dev/null
+++ b/kernel/include/libk/list.h
@@ -0,0 +1,14 @@
+#ifndef LIST_H
+#define LIST_H
+
+struct list_t {
+	struct list_t* next;
+	void* data;
+};
+typedef struct list_t list_t;
+
+void add_to_list_head(list_t** ptr, void* data);
+void add_to_list_tail(list_t** ptr, void* data);
+void free_list(list_t** ptr);
+
+#endif
diff --git a/kernel/include/multiboot2.h b/kernel/include/multiboot2.h
index e7935a6..6d4a86f 100644
--- a/kernel/include/multiboot2.h
+++ b/kernel/include/multiboot2.h
@@ -21,6 +21,23 @@ struct mb2_tag_fb {
 } __attribute__((packed, aligned(8)));
 typedef struct mb2_tag_fb mb2_tag_fb;
 
+struct mb2_tag_mmap {
+	uint32_t type;
+	uint32_t size;
+	uint32_t entry_size;
+	uint32_t entry_version;
+};
+typedef struct mb2_tag_mmap mb2_tag_mmap;
+
+struct mb2_tag_mmap_entry {
+	uint64_t base_addr;
+	uint64_t length;
+	uint32_t type;
+	uint32_t reserved;
+};
+typedef struct mb2_tag_mmap_entry mb2_tag_mmap_entry;
+
+
 // multiboot2 magic check
 #define MB2_MAGIC		0x36D76289
 
@@ -35,6 +52,9 @@ typedef struct mb2_tag_fb mb2_tag_fb;
 #define MB2_TAG_VBE		7
 #define MB2_TAG_FB		8
 
-void init_fb(mb2_tag_header* multiboot_bootinfo, uint32_t multiboot_magic);
+
+void read_mb2(mb2_tag_header* multiboot_bootinfo, uint32_t multiboot_magic);
+void init_fb(mb2_tag_fb* tag_fb);
+void init_mmap(mb2_tag_mmap* tag_mmap);
 
 #endif
diff --git a/kernel/src/boot/multiboot2.c b/kernel/src/boot/multiboot2.c
index 9c2998f..d0b0667 100644
--- a/kernel/src/boot/multiboot2.c
+++ b/kernel/src/boot/multiboot2.c
@@ -2,14 +2,59 @@
 #include <multiboot2.h>
 
 #include <graphics.h>
-#include <debug.h>
 #include <paging.h>
 
+#include <libk/stdio.h>
+#include <libk/string.h>
+#include <libk/list.h>
+#include <heap.h>
+
 #define KERNEL_VMA 0xc0000000
 
 /* https://www.gnu.org/software/grub/manual/multiboot2/html_node/Boot-information-format.html */
 
-void init_fb(mb2_tag_header* multiboot_bootinfo, uint32_t multiboot_magic)
+void init_fb(mb2_tag_fb* tag_fb)
+{
+	main_fb.addr = tag_fb->framebuffer_addr;
+	main_fb.width = tag_fb->framebuffer_width;
+	main_fb.height = tag_fb->framebuffer_height;
+	main_fb.pitch = tag_fb->framebuffer_pitch;
+	main_fb.bpp = tag_fb->framebuffer_bpp;
+
+	// identity map framebuffer address
+	map_addr(main_fb.addr, main_fb.addr, FLAG_PRESENT + FLAG_WRITABLE + FLAG_HUGE);
+	map_addr(main_fb.addr + PAGE_SIZE, main_fb.addr + PAGE_SIZE, FLAG_PRESENT + FLAG_WRITABLE + FLAG_HUGE);
+}
+
+void init_mmap(mb2_tag_mmap* tag_mmap)
+{
+	list_t* mmap = NULL;
+
+	// get data and store it into list
+	for (size_t i = sizeof(mb2_tag_mmap); i < tag_mmap->size; i += sizeof(mb2_tag_mmap_entry)) {
+		mb2_tag_mmap_entry* mmap_entry;
+		mmap_entry = (mb2_tag_mmap_entry*)kalloc(sizeof(mb2_tag_mmap_entry));
+		memcpy(mmap_entry, (char*)tag_mmap + i, sizeof(mb2_tag_mmap_entry));
+		add_to_list_head(&mmap, mmap_entry);
+	}
+
+	// print data from list
+	for (list_t* tmp = mmap; tmp != NULL; tmp = tmp->next) {
+		mb2_tag_mmap_entry* mmap_entry;
+		mmap_entry = tmp->data;
+		printf("base_addr: 0x%x, length: 0x%x, type: %d\n", mmap_entry->base_addr, mmap_entry->length, mmap_entry->type);
+	}
+
+	// free data
+	for (list_t* tmp = mmap; tmp != NULL; tmp = tmp->next) {
+		kfree(tmp->data);
+	}
+
+	// free list
+	free_list(&mmap);
+}
+
+void read_mb2(mb2_tag_header* multiboot_bootinfo, uint32_t multiboot_magic)
 {
 	if (multiboot_magic != MB2_MAGIC) {
 		// not loaded by multiboot2 bootloader
@@ -18,6 +63,7 @@ void init_fb(mb2_tag_header* multiboot_bootinfo, uint32_t multiboot_magic)
 
 	// we will store framebuffer information here
 	static mb2_tag_fb* tag_fb;
+	static mb2_tag_mmap* tag_mmap;
 
 	// skip first 8 bytes (total_size + reserved)
 	mb2_tag_header* tag_header = (mb2_tag_header*)((char*)multiboot_bootinfo + 8 + KERNEL_VMA);
@@ -28,6 +74,9 @@ void init_fb(mb2_tag_header* multiboot_bootinfo, uint32_t multiboot_magic)
 			case MB2_TAG_FB:
 				tag_fb = (mb2_tag_fb*)tag_header;
 				break;
+			case MB2_TAG_MMAP:
+				tag_mmap = (mb2_tag_mmap*)tag_header;
+				break;
 			default:
 				break;
 		}
@@ -36,13 +85,6 @@ void init_fb(mb2_tag_header* multiboot_bootinfo, uint32_t multiboot_magic)
 		tag_header += tag_header->size / 8 + ((tag_header->size % 8) > 0);
 	}
 
-	main_fb.addr = tag_fb->framebuffer_addr;
-	main_fb.width = tag_fb->framebuffer_width;
-	main_fb.height = tag_fb->framebuffer_height;
-	main_fb.pitch = tag_fb->framebuffer_pitch;
-	main_fb.bpp = tag_fb->framebuffer_bpp;
-
-	// identity map framebuffer address
-	map_addr(main_fb.addr, main_fb.addr, FLAG_PRESENT + FLAG_WRITABLE + FLAG_HUGE);
-	map_addr(main_fb.addr + PAGE_SIZE, main_fb.addr + PAGE_SIZE, FLAG_PRESENT + FLAG_WRITABLE + FLAG_HUGE);
+	init_fb(tag_fb);
+	init_mmap(tag_mmap);
 }
diff --git a/kernel/src/libk/list.c b/kernel/src/libk/list.c
new file mode 100644
index 0000000..5f75845
--- /dev/null
+++ b/kernel/src/libk/list.c
@@ -0,0 +1,37 @@
+#include <libk/list.h>
+#include <heap.h>
+
+void add_to_list_head(list_t** ptr, void* data)
+{
+	list_t* node = (list_t*)kalloc(sizeof(list_t));
+	node->data = data;
+
+	node->next = *ptr;
+	*ptr = node;
+}
+
+void add_to_list_tail(list_t** ptr, void* data)
+{
+	list_t* node = (list_t*)kalloc(sizeof(list_t));
+	node->data = data;
+
+	if (*ptr == NULL) {
+		*ptr = node;
+	} else {
+		list_t* tmp = *ptr;
+		while (tmp->next != NULL)
+			tmp = tmp->next;
+		tmp->next = node;
+	}
+}
+
+void free_list(list_t** ptr)
+{
+	if (*ptr == NULL)
+		return;
+
+	for (list_t* tmp = (*ptr)->next; tmp != NULL; tmp = tmp->next) {
+		kfree(*ptr);
+		*ptr = tmp;
+	}
+}
diff --git a/kernel/src/main.c b/kernel/src/main.c
index 95951bd..a3303e4 100644
--- a/kernel/src/main.c
+++ b/kernel/src/main.c
@@ -16,23 +16,7 @@ int kernel_main(mb2_tag_header* multiboot_bootinfo, uint32_t multiboot_magic)
 	init_paging();
 	init_idt();
 	init_heap();
-	init_fb(multiboot_bootinfo, multiboot_magic);
-
-	size_t n = 15;
-	uint16_t* a = (uint16_t*)kalloc(sizeof(uint16_t) * (uint32_t)n);
-	for (size_t i = 0; i < n; i++) {
-		a[i] = (uint16_t)i + 250;
-	}
-
-	uint8_t* b = (uint8_t*)kalloc(sizeof(uint16_t) * (uint32_t)n);
-	memcpy(b, a, sizeof(uint16_t) * n);
-
-	for (size_t i = 0; i < 2 * n; i++) {
-		printf("b[%d] = %d\n", i, b[i]);
-	}
-
-	__asm__ volatile ("movq $4, 0x1000000;");
-
+	read_mb2(multiboot_bootinfo, multiboot_magic);
 
 	for(;;) {
 		__asm__ volatile ("hlt;");