diff --git a/src/lib/ultra/io/pirawdma.c b/src/lib/ultra/io/pirawdma.c
index 970a55d68..53a28b404 100644
--- a/src/lib/ultra/io/pirawdma.c
+++ b/src/lib/ultra/io/pirawdma.c
@@ -1,63 +1,24 @@
 #include <libultra_internal.h>
 
-GLOBAL_ASM(
-glabel osPiRawStartDma
-/*    49b50:	27bdffe8 */ 	addiu	$sp,$sp,-24
-/*    49b54:	3c03a460 */ 	lui	$v1,0xa460
-/*    49b58:	34630010 */ 	ori	$v1,$v1,0x10
-/*    49b5c:	afbf0014 */ 	sw	$ra,0x14($sp)
-/*    49b60:	afa40018 */ 	sw	$a0,0x18($sp)
-/*    49b64:	afa5001c */ 	sw	$a1,0x1c($sp)
-/*    49b68:	8c620000 */ 	lw	$v0,0x0($v1)
-/*    49b6c:	00c02025 */ 	or	$a0,$a2,$zero
-/*    49b70:	304e0003 */ 	andi	$t6,$v0,0x3
-/*    49b74:	11c00005 */ 	beqz	$t6,.L00049b8c
-/*    49b78:	00000000 */ 	nop
-/*    49b7c:	8c620000 */ 	lw	$v0,0x0($v1)
-.L00049b80:
-/*    49b80:	304f0003 */ 	andi	$t7,$v0,0x3
-/*    49b84:	55e0fffe */ 	bnezl	$t7,.L00049b80
-/*    49b88:	8c620000 */ 	lw	$v0,0x0($v1)
-.L00049b8c:
-/*    49b8c:	0c012d20 */ 	jal	osVirtualToPhysical
-/*    49b90:	afa70024 */ 	sw	$a3,0x24($sp)
-/*    49b94:	8fa30018 */ 	lw	$v1,0x18($sp)
-/*    49b98:	8fa70024 */ 	lw	$a3,0x24($sp)
-/*    49b9c:	3c18a460 */ 	lui	$t8,0xa460
-/*    49ba0:	af020000 */ 	sw	$v0,0x0($t8)
-/*    49ba4:	3c198000 */ 	lui	$t9,0x8000
-/*    49ba8:	8f390308 */ 	lw	$t9,0x308($t9)
-/*    49bac:	8fa8001c */ 	lw	$t0,0x1c($sp)
-/*    49bb0:	3c011fff */ 	lui	$at,0x1fff
-/*    49bb4:	3421ffff */ 	ori	$at,$at,0xffff
-/*    49bb8:	03284825 */ 	or	$t1,$t9,$t0
-/*    49bbc:	01215024 */ 	and	$t2,$t1,$at
-/*    49bc0:	3c0ba460 */ 	lui	$t3,0xa460
-/*    49bc4:	10600006 */ 	beqz	$v1,.L00049be0
-/*    49bc8:	ad6a0004 */ 	sw	$t2,0x4($t3)
-/*    49bcc:	24010001 */ 	addiu	$at,$zero,0x1
-/*    49bd0:	10610007 */ 	beq	$v1,$at,.L00049bf0
-/*    49bd4:	24eeffff */ 	addiu	$t6,$a3,-1
-/*    49bd8:	1000000b */ 	b	.L00049c08
-/*    49bdc:	2402ffff */ 	addiu	$v0,$zero,-1
-.L00049be0:
-/*    49be0:	24ecffff */ 	addiu	$t4,$a3,-1
-/*    49be4:	3c0da460 */ 	lui	$t5,0xa460
-/*    49be8:	10000006 */ 	b	.L00049c04
-/*    49bec:	adac000c */ 	sw	$t4,0xc($t5)
-.L00049bf0:
-/*    49bf0:	3c0fa460 */ 	lui	$t7,0xa460
-/*    49bf4:	10000003 */ 	b	.L00049c04
-/*    49bf8:	adee0008 */ 	sw	$t6,0x8($t7)
-/*    49bfc:	10000002 */ 	b	.L00049c08
-/*    49c00:	2402ffff */ 	addiu	$v0,$zero,-1
-.L00049c04:
-/*    49c04:	00001025 */ 	or	$v0,$zero,$zero
-.L00049c08:
-/*    49c08:	8fbf0014 */ 	lw	$ra,0x14($sp)
-/*    49c0c:	27bd0018 */ 	addiu	$sp,$sp,0x18
-/*    49c10:	03e00008 */ 	jr	$ra
-/*    49c14:	00000000 */ 	nop
-/*    49c18:	00000000 */ 	nop
-/*    49c1c:	00000000 */ 	nop
-);
+s32 osPiRawStartDma(s32 direction, u32 devAddr, void *dramAddr, u32 size)
+{
+	register u32 stat;
+
+	WAIT_ON_IOBUSY(stat);
+
+	IO_WRITE(PI_DRAM_ADDR_REG, osVirtualToPhysical(dramAddr));
+	IO_WRITE(PI_CART_ADDR_REG, K1_TO_PHYS((u32)osRomBase | devAddr));
+
+	switch (direction) {
+	case OS_READ:
+		IO_WRITE(PI_WR_LEN_REG, size - 1);
+		break;
+	case OS_WRITE:
+		IO_WRITE(PI_RD_LEN_REG, size - 1);
+		break;
+	default:
+		return -1;
+	}
+
+	return 0;
+}