Kernel: Stop bootloader from setting video mode with Multiboot

Meta: Update INSTALL.md and grub configs for new boot_mode option

5 files changed, 18 insertions, 10 deletions

diff --git a/INSTALL.md b/INSTALL.md
index 0998786377..07345f3e2a 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -47,4 +47,4 @@ $ cu -s 57600 -l /dev/ttyUSB0
 
 ## Troubleshooting boot issues without a serial port
 
-Serenity is a graphical OS and thus boots directly to the desktop. If your computer doesn't have a serial port and it fails to boot, you can force Serenity to boot into text mode by editing **Kernel/Arch/i386/Boot/boot.S** and removing **| MULTIBOOT_VIDEO_MODE** from the end of the **multiboot_flags** line before (re)running **make** and **make install**.
+Serenity is a graphical OS and thus boots directly to the desktop. If your computer doesn't have a serial port and it fails to boot, you can force Serenity to boot into text mode by selecting the **SerenityOS (text mode)** option in GRUB.
diff --git a/Kernel/Arch/i386/Boot/boot.S b/Kernel/Arch/i386/Boot/boot.S
index 601a50a7ac..f52db9d726 100644
--- a/Kernel/Arch/i386/Boot/boot.S
+++ b/Kernel/Arch/i386/Boot/boot.S
@@ -1,8 +1,7 @@
 .set MULTIBOOT_MAGIC,         0x1badb002
 .set MULTIBOOT_PAGE_ALIGN,    0x1
 .set MULTIBOOT_MEMORY_INFO,   0x2
-.set MULTIBOOT_VIDEO_MODE,    0x4
-.set multiboot_flags,         MULTIBOOT_PAGE_ALIGN | MULTIBOOT_MEMORY_INFO | MULTIBOOT_VIDEO_MODE
+.set multiboot_flags,         MULTIBOOT_PAGE_ALIGN | MULTIBOOT_MEMORY_INFO
 .set multiboot_checksum,      -(MULTIBOOT_MAGIC + multiboot_flags)
 
 .section .multiboot
@@ -20,12 +19,6 @@
 .long 0x00000000    /* bss_end_addr */
 .long 0x00000000    /* entry_addr */
 
-/* for MULTIBOOT_VIDEO_MODE */
-.long 0x00000000    /* mode_type */
-.long 1280          /* width */
-.long 1024          /* height */
-.long 32            /* depth */
-
 .section .stack, "aw", @nobits
 stack_bottom:
 .skip 32768
diff --git a/Meta/grub-ebr.cfg b/Meta/grub-ebr.cfg
index 2b351ce72f..f865bb9162 100644
--- a/Meta/grub-ebr.cfg
+++ b/Meta/grub-ebr.cfg
@@ -5,6 +5,11 @@ menuentry 'SerenityOS (normal)' {
   multiboot /boot/Kernel root=/dev/hda5
 }
 
+menuentry 'SerenityOS (text mode)' {
+  root=hd0,5
+  multiboot /boot/Kernel boot_mode=text root=/dev/hda5
+}
+
 menuentry 'SerenityOS (No ACPI)' {
   root=hd0,5
   multiboot /boot/Kernel root=/dev/hda5 acpi=off
diff --git a/Meta/grub-gpt.cfg b/Meta/grub-gpt.cfg
index 9de1494daa..13addb2ab8 100644
--- a/Meta/grub-gpt.cfg
+++ b/Meta/grub-gpt.cfg
@@ -5,6 +5,11 @@ menuentry 'SerenityOS (normal)' {
   multiboot /boot/Kernel root=/dev/hda2
 }
 
+menuentry 'SerenityOS (text mode)' {
+  root=hd0,2
+  multiboot /boot/Kernel boot_mode=text root=/dev/hda2
+}
+
 menuentry 'SerenityOS (No ACPI)' {
   root=hd0,2
   multiboot /boot/Kernel root=/dev/hda2 acpi=off
diff --git a/Meta/grub-mbr.cfg b/Meta/grub-mbr.cfg
index bbb37ffc66..f5cbf252bc 100644
--- a/Meta/grub-mbr.cfg
+++ b/Meta/grub-mbr.cfg
@@ -5,12 +5,17 @@ menuentry 'SerenityOS (normal)' {
   multiboot /boot/Kernel root=/dev/hda1
 }
 
+menuentry 'SerenityOS (text mode)' {
+  root=hd0,1
+  multiboot /boot/Kernel boot_mode=text root=/dev/hda1
+}
+
 menuentry 'SerenityOS (No ACPI)' {
   root=hd0,1
   multiboot /boot/Kernel root=/dev/hda1 acpi=off
 }
 
 menuentry 'SerenityOS (with serial debug)' {
-	root=hd0,1
+  root=hd0,1
   multiboot /boot/Kernel serial_debug root=/dev/hda1
 }