diff --git a/src/lib/ultra/os/unmaptlball.c b/src/lib/ultra/os/unmaptlball.c
deleted file mode 100644
index e1a4fa4c1..000000000
--- a/src/lib/ultra/os/unmaptlball.c
+++ /dev/null
@@ -1,24 +0,0 @@
-#include <libultra_internal.h>
-#include "data.h"
-
-GLOBAL_ASM(
-glabel osUnmapTLBAll
-/*    52080:	40085000 */ 	mfc0	$t0,$10
-/*    52084:	2409001e */ 	li	$t1,0x1e
-/*    52088:	3c0a8000 */ 	lui	$t2,0x8000
-/*    5208c:	408a5000 */ 	mtc0	$t2,$10
-/*    52090:	40801000 */ 	mtc0	$zero,$2
-/*    52094:	40801800 */ 	mtc0	$zero,$3
-.PF00052098:
-/*    52098:	40890000 */ 	mtc0	$t1,$0
-/*    5209c:	00000000 */ 	nop
-/*    520a0:	42000002 */ 	tlbwi
-/*    520a4:	00000000 */ 	nop
-/*    520a8:	00000000 */ 	nop
-/*    520ac:	2129ffff */ 	addi	$t1,$t1,-1
-/*    520b0:	0521fff9 */ 	bgez	$t1,.PF00052098
-/*    520b4:	00000000 */ 	nop
-/*    520b8:	40885000 */ 	mtc0	$t0,$10
-/*    520bc:	03e00008 */ 	jr	$ra
-/*    520c0:	00000000 */ 	nop
-);
diff --git a/src/lib/ultra/os/unmaptlball.s b/src/lib/ultra/os/unmaptlball.s
new file mode 100644
index 000000000..f1d99fea6
--- /dev/null
+++ b/src/lib/ultra/os/unmaptlball.s
@@ -0,0 +1,25 @@
+#include "macros.inc"
+.set noat
+.set noreorder
+
+.section .text
+
+glabel osUnmapTLBAll
+	mfc0  $t0, $10
+	li    $t1, 0x1e
+	lui   $t2, 0x8000
+	mtc0  $t2, $10
+	mtc0  $zero, $2
+	mtc0  $zero, $3
+.PF00052098:
+	mtc0  $t1, $0
+ 	nop
+ 	tlbwi
+ 	nop
+ 	nop
+	addi  $t1, $t1, -1
+	bgez  $t1, .PF00052098
+ 	nop
+	mtc0  $t0, $10
+	jr    $ra
+ 	nop