From d88f9cef04fd47ca1fc246731354a704ab48c6be Mon Sep 17 00:00:00 2001
From: Ryan Dwyer <ryandwyer1@gmail.com>
Date: Sat, 30 Jan 2021 10:33:14 +1000
Subject: [PATCH] Decompile __osAiDeviceBusy

---
 Makefile                    |  1 +
 ld/libfiles.inc             |  2 +-
 src/include/lib/lib_51ec0.h |  8 --------
 src/lib/lib_51ec0.c         | 19 -------------------
 src/lib/ultra/io/ai.c       | 12 ++++++++++++
 5 files changed, 14 insertions(+), 28 deletions(-)
 delete mode 100644 src/include/lib/lib_51ec0.h
 delete mode 100644 src/lib/lib_51ec0.c
 create mode 100644 src/lib/ultra/io/ai.c

diff --git a/Makefile b/Makefile
index b0d611fc7..b9d26d2a5 100644
--- a/Makefile
+++ b/Makefile
@@ -68,6 +68,7 @@ $(B_DIR)/lib/ultra/gu/ortho.o: LOOPUNROLL :=
 $(B_DIR)/lib/ultra/libc/ll.o: MIPSISET := -mips3 -o32
 $(B_DIR)/lib/ultra/libc/llcvt.o: MIPSISET := -mips3 -o32
 
+$(B_DIR)/lib/ultra/io/ai.o: OPT_LVL := -O1
 $(B_DIR)/lib/ultra/io/aisetnextbuf.o: OPT_LVL := -O1
 $(B_DIR)/lib/ultra/io/dpctr.o: OPT_LVL := -O1
 $(B_DIR)/lib/ultra/io/pigetcmdq.o: OPT_LVL := -O1
diff --git a/ld/libfiles.inc b/ld/libfiles.inc
index 08e572f05..51a5f6df8 100644
--- a/ld/libfiles.inc
+++ b/ld/libfiles.inc
@@ -187,7 +187,7 @@
 	build/ROMID/lib/ultra/io/si.o (section); \
 	build/ROMID/lib/ultra/os/probetlb.o (section); \
 	build/ROMID/lib/lib_51d50.o (section); \
-	build/ROMID/lib/lib_51ec0.o (section); \
+	build/ROMID/lib/ultra/io/ai.o (section); \
 	build/ROMID/lib/ultra/os/jammesg.o (section); \
 	build/ROMID/lib/ultra/io/pigetcmdq.o (section); \
 	build/ROMID/lib/ultra/io/pirawread.o (section); \
diff --git a/src/include/lib/lib_51ec0.h b/src/include/lib/lib_51ec0.h
deleted file mode 100644
index 6d8739a5e..000000000
--- a/src/include/lib/lib_51ec0.h
+++ /dev/null
@@ -1,8 +0,0 @@
-#ifndef _IN_LIB_LIB_51EC0_H
-#define _IN_LIB_LIB_51EC0_H
-#include <ultra64.h>
-#include "types.h"
-
-u32 __osAiDeviceBusy(void);
-
-#endif
diff --git a/src/lib/lib_51ec0.c b/src/lib/lib_51ec0.c
deleted file mode 100644
index 12d3a8256..000000000
--- a/src/lib/lib_51ec0.c
+++ /dev/null
@@ -1,19 +0,0 @@
-#include <ultra64.h>
-
-GLOBAL_ASM(
-glabel __osAiDeviceBusy
-/*    51ec0:	3c0ea450 */ 	lui	$t6,0xa450
-/*    51ec4:	8dc4000c */ 	lw	$a0,0xc($t6)
-/*    51ec8:	3c018000 */ 	lui	$at,0x8000
-/*    51ecc:	27bdfff8 */ 	addiu	$sp,$sp,-8
-/*    51ed0:	00817824 */ 	and	$t7,$a0,$at
-/*    51ed4:	11e00003 */ 	beqz	$t7,.L00051ee4
-/*    51ed8:	00000000 */ 	nop
-/*    51edc:	10000002 */ 	b	.L00051ee8
-/*    51ee0:	24020001 */ 	addiu	$v0,$zero,0x1
-.L00051ee4:
-/*    51ee4:	00001025 */ 	or	$v0,$zero,$zero
-.L00051ee8:
-/*    51ee8:	03e00008 */ 	jr	$ra
-/*    51eec:	27bd0008 */ 	addiu	$sp,$sp,0x8
-);
diff --git a/src/lib/ultra/io/ai.c b/src/lib/ultra/io/ai.c
new file mode 100644
index 000000000..1f85ea9b4
--- /dev/null
+++ b/src/lib/ultra/io/ai.c
@@ -0,0 +1,12 @@
+#include <ultra64.h>
+
+s32 __osAiDeviceBusy(void)
+{
+	register s32 status = IO_READ(AI_STATUS_REG);
+
+	if (status & AI_STATUS_FIFO_FULL) {
+		return 1;
+	}
+
+	return 0;
+}