Disable serial debug output by default.

EFI doesn't have a boot keys mechanism so we just disable the
routine that enables it entirely. Also disable it in early kernel
output before the settings file has been read.

data/settings/kernel/drivers/kernel

@@ -28,7 +28,7 @@ load_symbols true
 #emergency_keys false
 	# Disables emergency keys (ie. Alt-SysReq+*), enabled by default.
 
-#serial_debug_output false
+serial_debug_output false
 	# Disables serial debug output, which is enabled by default
 
 #serial_debug_port 1

src/system/boot/platform/bios_ia32/start.cpp

@@ -184,7 +184,7 @@ _start(void)
 	args.arguments = NULL;
 
 	serial_init();
-	serial_enable();
+	//serial_enable();
 	interrupts_init();
 	console_init();
 	cpu_init();
@@ -195,8 +195,8 @@ _start(void)
 	// reading the keyboard doesn't seem to work in graphics mode
 	// (maybe a bochs problem)
 	sBootOptions = check_for_boot_keys();
-//	if (sBootOptions & BOOT_OPTION_DEBUG_OUTPUT)
+	if (sBootOptions & BOOT_OPTION_DEBUG_OUTPUT)
-//		serial_enable();
+		serial_enable();
 
 	apm_init();
 	acpi_init();

src/system/boot/platform/efi/serial.cpp

@@ -97,9 +97,11 @@ serial_disable(void)
 extern "C" void
 serial_enable(void)
 {
+#if 0
 	sSerialEnabled = true;
 	if ((gUART != NULL) && !gUARTSkipInit)
 		gUART->InitPort(kSerialBaudRate);
+#endif
 }
 
 

src/system/kernel/main.cpp

@@ -133,7 +133,7 @@ _start(kernel_args *bootKernelArgs, int currentCPU)
 
 		// setup debug output
 		debug_init(&sKernelArgs);
-		set_dprintf_enabled(true);
+		set_dprintf_enabled(false);
 		dprintf("Welcome to kernel debugger output!\n");
 		dprintf("Haiku revision: %s, debug level: %d\n", get_haiku_revision(),
 			KDEBUG_LEVEL);