4 files changed, 65 insertions, 7 deletions

diff --git a/src/kernel/boot.asm b/src/kernel/boot.asm
index c0b3735..7c7f5d9 100644
--- a/src/kernel/boot.asm
+++ b/src/kernel/boot.asm
@@ -1,5 +1,6 @@
 [bits 32]
 global start
+global vbe_init_structure
 start:
     mov esp, _sys_stack ; Points stack to stack area
     jmp stublet
@@ -44,6 +45,10 @@ stublet:
 
 %include "src/kernel/interact.asm"
 
+vbe_init_structure:
+	.signature db "VBE2"
+	.table_data: resb 512-4
+
 ; Store the stack
 SECTION .bss
     resb 8192 ; Reserve 8KiB
diff --git a/src/kernel/graphics/vesa.c b/src/kernel/graphics/vesa.c
index af2502b..cab6c70 100644
--- a/src/kernel/graphics/vesa.c
+++ b/src/kernel/graphics/vesa.c
@@ -1,4 +1,12 @@
 #include "vesa.h"
+#include "graphics.h"
+#include "../sound/sound.h"
+#include "../lib/lib.h"
+#include "../acpi/acpi.h"
+
+void switch_to_vga() {
+    terminal_initialize();
+}
 
 vbe_mode_info *vbe_set_mode(unsigned short mode) {
     regs16_t regs;
@@ -13,7 +21,7 @@ vbe_mode_info *vbe_set_mode(unsigned short mode) {
         regs.es = 0xA000;
         int32(0x10, &regs);
         if (regs.ax != 0x004F) {
-            // Add VGA redirect
+            switch_to_vga();
         }
 
         vbe_mode_info *vbe_info = (vbe_mode_info *) 0xA0000;
@@ -24,8 +32,10 @@ vbe_mode_info *vbe_set_mode(unsigned short mode) {
         vbe_pitch = vbe_info->pitch;
 
         char *fb = (char *) vbe_info->framebuffer;
-        for (int i = 0; i < 640 * 480 * 3; i++) {
+        for (int i = 0; i < vbe_width * vbe_height * vbe_bpp; i++) {
             fb[i] = 100;
+            fb[i + 1] = 100;
+            fb[i + 2] = 100;
         }
         regs.ax = 0x0000;
         int32(0x16, &regs);
@@ -34,9 +44,32 @@ vbe_mode_info *vbe_set_mode(unsigned short mode) {
 
         return vbe_info;
     } else {
-        // Add VGA redirect
+        switch_to_vga();
     }
 
     vbe_mode_info vbe_info;
     return &vbe_info;
 }
+
+void set_optimal_resolution() {
+    extern vbe_info *vbe_init_structure;
+    regs16_t regs;
+    regs.ax = 0x4F01;
+    regs.cx = vbe_init_structure;
+    regs.di = 0x0000;
+    regs.es = 0xA000;
+    int32(0x10, &regs);
+
+    if (regs.ax != 0x004F) {
+        switch_to_vga();
+    }
+
+    vbe_info *vbe_modes = (vbe_info *) 0xA0000;
+    if (strcmp(vbe_modes->signature, "VESA") == 0) {
+        loop:
+        asm volatile ("hlt");
+        goto loop;
+    } else {
+        acpi_poweroff();
+    }
+}
\ No newline at end of file
diff --git a/src/kernel/graphics/vesa.h b/src/kernel/graphics/vesa.h
index fb9ff54..dd67123 100644
--- a/src/kernel/graphics/vesa.h
+++ b/src/kernel/graphics/vesa.h
@@ -4,6 +4,21 @@
 #include <stdint.h>
 
 typedef struct __attribute__ ((packed)) {
+    char signature[4];    // must be "VESA" to indicate valid VBE support
+    uint32_t version;            // VBE version; high byte is major version, low byte is minor version
+    uint32_t oem;            // segment:offset pointer to OEM
+    uint32_t capabilities;        // bitfield that describes card capabilities
+    uint32_t video_modes;        // segment:offset pointer to list of supported video modes
+    uint32_t video_memory;        // amount of video memory in 64KB blocks
+    uint32_t software_rev;        // software revision
+    uint32_t vendor;            // segment:offset to card vendor string
+    uint32_t product_name;        // segment:offset to card model name
+    uint32_t product_rev;        // segment:offset pointer to product revision
+    char reserved[222];        // reserved for future expansion
+    char oem_data[256];        // OEM BIOSes store their strings in this area
+} vbe_info;
+
+typedef struct __attribute__ ((packed)) {
     uint16_t attributes;        // deprecated, only bit 7 should be of interest to you, and it indicates the mode supports a linear frame buffer.
     uint8_t window_a;            // deprecated
     uint8_t window_b;            // deprecated
@@ -43,6 +58,8 @@ typedef struct __attribute__ ((packed)) {
 
 vbe_mode_info *vbe_set_mode(unsigned short mode);
 
+void set_optimal_resolution();
+
 typedef struct __attribute__ ((packed)) {
     unsigned short di, si, bp, sp, bx, dx, cx, ax;
     unsigned short gs, fs, es, ds, eflags;
diff --git a/src/kernel/kernel.c b/src/kernel/kernel.c
index d0356f4..26eee7c 100644
--- a/src/kernel/kernel.c
+++ b/src/kernel/kernel.c
@@ -1,3 +1,4 @@
+#include "graphics/vesa.h"
 #include "graphics/graphics.h"
 #include "gdt/gdt.h"
 #include "interrupts/interrupts.h"
@@ -10,14 +11,16 @@ void kernel_main(void) {
     idt_install();
     isrs_install();
     irq_install();
+    timer_install();
 
-    vbe_set_mode(0x11B); // 1280x1024
+    // vbe_set_mode(0x11B); // 1280x1024
 
-    // terminal_initialize();
-    // terminal_write_string("Melvix loaded successfully!\n");
+    terminal_initialize();
+    terminal_write_string("Melvix loaded successfully!\n");
 
-    timer_install();
+    set_optimal_resolution();
     keyboard_install();
     // mouse_install();
+
     // __asm__  ("div %0" :: "r"(0)); // Exception testing x/0
 }
\ No newline at end of file