LibPSn00b officially v0.10b, added psxsio library, better DrawSync() and VSync(), better reference manual.

14 files changed, 799 insertions, 240 deletions

diff --git a/libpsn00b/psxgpu/dmacallback.s b/libpsn00b/psxgpu/dmacallback.s
new file mode 100644
index 0000000..b2f86cf
--- /dev/null
+++ b/libpsn00b/psxgpu/dmacallback.s
@@ -0,0 +1,191 @@
+.set noreorder
+
+.include "hwregs_a.h"
+
+.section .text
+
+.global DMACallback
+.type DMACallback, @function
+DMACallback:
+
+	# a0 - DMA channel
+	# a1 - Callback function
+	
+	addiu	$sp, -8
+	sw		$ra, 0($sp)
+
+	beqz	$a1, .Lremove_cb		# Remove callback if function is NULL
+	nop
+	
+	addiu	$sp, -8					# Install IRQ handler for DMA handler
+	sw		$a0, 0($sp)				# if not set installed yet
+	sw		$a1, 4($sp)
+	
+	jal		GetInterruptCallback
+	li		$a0, 3
+	
+	bnez	$v0, .Lskip_install
+	nop
+	
+	la		$a1, _dma_handler
+	jal		InterruptCallback
+	li		$a0, 3
+
+.Lskip_install:
+	
+	lw		$a0, 0($sp)
+	lw		$a1, 4($sp)
+	addiu	$sp, 8
+	
+	la		$v0, _dma_func_table
+	sll		$v1, $a0, 2
+	addu	$v0, $v1
+	lw		$v1, 0($v0)
+	sw		$a1, 0($v0)
+	sw		$v1, 4($sp)
+	
+	lui		$a2, IOBASE
+	
+	lw		$v0, DICR($a2)			# Enable DMA interrupt
+	lui		$v1, 0x1
+	sll		$v1, $a0
+	or		$v0, $v1
+	lui		$v1, 0x80
+	or		$v0, $v1
+	sw		$v0, DICR($a2)
+	
+	b		.Lskip_remove
+	nop
+	
+.Lremove_cb:
+
+	la		$v0, _dma_func_table	# Set callback address
+	sll		$v1, $a0, 2
+	addu	$v0, $v1
+	lw		$v1, 0($v0)
+	sw		$a1, 0($v0)
+	sw		$v1, 4($sp)
+	
+	lui		$a2, IOBASE				# Disable DMA interrupt
+	lw		$v0, DICR($a2)
+	lui		$v1, 0x1
+	sll		$v1, $a0
+	.set noat
+	addiu	$at, $0, -1
+	xor		$v1, $at
+	and		$v0, $v1
+	lui		$v1, 0x7f00
+	xor		$v1, $at
+	and		$v0, $v1
+	.set at
+	sw		$v0, DICR($a2)
+	
+	jal		_dma_has_cb				# Check if callbacks are present
+	nop
+	bnez	$v0, .Lskip_remove
+	nop
+	sw		$0 , DICR($a2)
+	
+	jal		GetInterruptCallback	# Check if callback is the DMA handler
+	li		$a0, 3
+	la		$v1, _dma_handler
+	bne		$v0, $v1, .Lskip_remove
+	nop
+	
+	li		$a0, 3
+	jal		InterruptCallback
+	move	$a1, $0
+	
+.Lskip_remove:
+	
+	lw		$ra, 0($sp)
+	lw		$v0, 4($sp)
+	jr		$ra
+	addiu	$sp, 8
+
+	
+.type _dma_has_cb, @function
+_dma_has_cb:
+
+	la		$v1, _dma_func_table
+	li		$t0, 6
+	
+.Lscan_loop:
+
+	lw		$v0, 0($v1)
+	addiu	$v1, 4
+	bnez	$v0, .Lhas_cb
+	nop
+	
+	bgtz	$t0, .Lscan_loop
+	addiu	$t0, -1
+	
+	jr		$ra
+	move	$v0, $0
+	
+.Lhas_cb:
+
+	jr		$ra
+	li		$v0, 1
+	
+	
+.type _dma_handler, @function
+_dma_handler:
+
+	addiu	$sp, -12
+	sw		$ra, 0($sp)
+	sw		$s0, 4($sp)
+	sw		$s1, 8($sp)
+	
+	move	$s0, $0
+	la		$s1, _dma_func_table
+	
+.Lhandler_loop:
+
+	lui		$a0, IOBASE
+	lw		$v0, DICR($a0)
+	li		$v1, 24
+	addu	$v1, $s0
+	srl		$v0, $v1
+	andi	$v0, 0x1
+	
+	lw		$v1, 0($s1)
+	
+	beqz	$v0, .Lno_irq
+	addiu	$s1, 4
+	
+	beqz	$v1, .Lno_irq
+	nop
+	
+	jalr	$v1
+	nop
+	
+.Lno_irq:
+	
+	blt		$s0, 6, .Lhandler_loop
+	addi	$s0, 1
+	
+	lui		$a0, IOBASE
+	lw		$v0, DICR($a0)
+	nop
+	sw		$v0, DICR($a0)
+	
+	lw		$ra, 0($sp)
+	lw		$s0, 4($sp)
+	lw		$s1, 8($sp)
+	
+	jr		$ra
+	addiu	$sp, -12
+	
+	
+.section .data
+
+_dma_func_table:
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	
\ No newline at end of file
diff --git a/libpsn00b/psxgpu/drawotag.s b/libpsn00b/psxgpu/drawotag.s
index 8a5ff0c..ba771fc 100644
--- a/libpsn00b/psxgpu/drawotag.s
+++ b/libpsn00b/psxgpu/drawotag.s
@@ -13,20 +13,20 @@ DrawOTag:
 
 	lui		$a3, 0x1f80			# I/O segment base
 
-.gpu_wait:						# Wait for GPU to be ready for commands & DMA
+	lui		$v0, 0x0400			# Set DMA direction to CPUtoGPU
+	ori		$v0, 0x2
+	sw		$v0, GP1($a3)
+	
+.Lgpu_wait:						# Wait for GPU to be ready for commands & DMA
 	jal		ReadGPUstat
 	nop
 	srl		$v0, 26
 	andi	$v0, 1
-	beqz	$v0, .gpu_wait
+	beqz	$v0, .Lgpu_wait
 	nop
 
-	lui		$v0, 0x0400			# Set DMA direction to CPUtoGPU
-	ori		$v0, 0x2
-	sw		$v0, GP1($a3)
-
 	sw		$a0, D2_MADR($a3)	# Set DMA base address to specified OT
-	sw		$0, D2_BCR($a3)
+	sw		$0 , D2_BCR($a3)
 
 	lui		$v0, 0x0100			# Begin OT transfer!
 	ori		$v0, 0x0401
diff --git a/libpsn00b/psxgpu/drawprim.s b/libpsn00b/psxgpu/drawprim.s
new file mode 100644
index 0000000..a216720
--- /dev/null
+++ b/libpsn00b/psxgpu/drawprim.s
@@ -0,0 +1,40 @@
+.set noreorder
+
+.include "hwregs_a.h"
+
+.text
+
+.global DrawPrim
+.type DrawPrim, @function
+DrawPrim:
+
+	addiu	$sp, -8
+	sw		$ra, 0($sp)
+	sw		$s0, 4($sp)
+	
+	move	$s0, $a0			# Wait for GPU to complete
+	jal		DrawSync
+	move	$a0, $0
+	
+	lui		$a3, IOBASE
+	lui		$v0, 0x0400			# Set transfer direction to off
+	sw		$v0, GP1($a3)
+	
+	move	$a0, $s0
+	lbu		$a1, 3($a0)			# Get length of primitive packet
+	addiu	$a0, 4
+	
+.Ltransfer_loop:
+	lw		$v0, 0($a0)
+	addiu	$a0, 4
+	sw		$v0, GP0($a3)
+	bgtz	$a1, .Ltransfer_loop
+	addiu	$a1, -1
+
+	jal		DrawSync
+	move	$a0, $0
+	
+	lw		$ra, 0($sp)
+	lw		$s0, 4($sp)
+	jr		$ra
+	addiu	$sp, 8
\ No newline at end of file
diff --git a/libpsn00b/psxgpu/drawsync.s b/libpsn00b/psxgpu/drawsync.s
index 149519d..66d37e2 100644
--- a/libpsn00b/psxgpu/drawsync.s
+++ b/libpsn00b/psxgpu/drawsync.s
@@ -8,19 +8,60 @@
 .global DrawSync
 .type DrawSync, @function
 DrawSync:
+
+	bnez	$a0, .Lgetwords
+	lui		$a0, IOBASE
+
 	addiu	$sp, -4
 	sw		$ra, 0($sp)
 
-.gpu_wait:						# Wait for GPU to be ready for commands and DMA
+	jal		ReadGPUstat			# Check if DMA enabled
+	nop
+	srl		$v0, 29
+	andi	$v0, 0x3
+	
+	beqz	$v0, .Lsimple_wait
+	nop
+	
+.Ldma_wait:
+	lw		$v0, D2_CHCR
+	nop
+	srl		$v0, 24
+	andi	$v0, 0x1
+	bnez	$v0, .Ldma_wait
+	nop
+
+.Lgpu_wait:
 	jal		ReadGPUstat
 	nop
-	srl		$v0, 0x1a
+	srl		$v0, 26
 	andi	$v0, 0x5
-	li		$v1, 5
-	bne		$v0, $v1, .gpu_wait
+	bne		$v0, 5, .Lgpu_wait
+	nop
+	
+	b		.Lexit
 	nop
+	
+.Lsimple_wait:					# Wait for GPU to be ready for next DMA
+	jal		ReadGPUstat
+	nop
+	srl		$v0, 28
+	andi	$v0, 0x1
+	beqz	$v0, .Lsimple_wait
+	nop
+
+.Lexit:
 
 	lw		$ra, 0($sp)
 	addiu	$sp, 4
 	jr		$ra
 	nop
+	
+.Lgetwords:
+
+	lw		$v0, D2_BCR($a0)
+	nop
+
+	jr		$ra
+	srl		$v0, 16
+	
\ No newline at end of file
diff --git a/libpsn00b/psxgpu/drawsynccallback.s b/libpsn00b/psxgpu/drawsynccallback.s
new file mode 100644
index 0000000..c1e28fe
--- /dev/null
+++ b/libpsn00b/psxgpu/drawsynccallback.s
@@ -0,0 +1,103 @@
+.set noreorder
+
+.include "hwregs_a.h"
+
+.text
+
+.global DrawSyncCallback
+.type DrawSyncCallback, @function
+DrawSyncCallback:
+
+	addiu	$sp, -8
+	sw		$ra, 0($sp)
+	sw		$a0, 4($sp)
+	
+	jal		EnterCriticalSection
+	nop
+	
+	beqz	$a0, .Luninstall
+	nop
+	la		$a1, _drawsync_handler
+	jal		DMACallback
+	li		$a0, 2
+	b		.Lcontinue
+	nop
+	
+.Luninstall:
+
+	move	$a1, $0
+	jal		DMACallback
+	li		$a0, 2
+
+.Lcontinue:
+
+	lw		$a0, 4($sp)
+	la		$v1, _drawsync_func
+	lw		$v0, 0($v1)
+	sw		$a0, 0($v1)
+	sw		$v0, 4($sp)
+	
+.Lexit:
+
+	jal		ExitCriticalSection
+	nop
+	
+	lw		$ra, 0($sp)
+	lw		$v0, 4($sp)
+	jr		$ra
+	addiu	$sp, 8
+	
+	
+.type _drawsync_handler, @function
+_drawsync_handler:
+
+.Ldma_wait:
+
+	la		$v0, _drawsync_func
+	lw		$v0, 0($v0)
+	nop
+	beqz	$v0, .Lskip
+	nop
+
+	addiu	$sp, -4
+	sw		$ra, 0($sp)
+
+	lw		$v0, D2_CHCR($a0)
+	nop
+	srl		$v0, 24
+	andi	$v0, 0x1
+	
+	bnez	$v0, .Ldma_wait
+	nop
+
+.Lgpu_wait:
+	jal		ReadGPUstat
+	nop
+	srl		$v0, 28
+	andi	$v0, 0x1
+	beqz	$v0, .Lgpu_wait
+	nop
+	
+	la		$v1, _drawsync_func
+	lw		$v1, 0($v1)
+	
+	lui		$v0, 0x0400			# Set DMA direction to off
+	sw		$v0, GP1($a0)
+	
+	jalr	$v1
+	nop
+	
+	lw		$ra, 0($sp)
+	addiu	$sp, 4
+	
+.Lskip:
+
+	jr		$ra
+	nop
+	
+
+.data
+
+_drawsync_func:
+	.word 0
+	
\ No newline at end of file
diff --git a/libpsn00b/psxgpu/getinterruptcallback.s b/libpsn00b/psxgpu/getinterruptcallback.s
new file mode 100644
index 0000000..b465567
--- /dev/null
+++ b/libpsn00b/psxgpu/getinterruptcallback.s
@@ -0,0 +1,17 @@
+.set noreorder
+
+.section .text
+
+.global GetInterruptCallback
+.type GetInterruptCallback, @function
+GetInterruptCallback:
+	
+	# a0 - Interrupt number
+	
+	la		$a1, _irq_func_table
+	sll		$a0, 2
+	addu	$a1, $a0
+	
+	jr		$ra
+	lw		$v0, 0($a1)
+	
\ No newline at end of file
diff --git a/libpsn00b/psxgpu/interruptcallback.s b/libpsn00b/psxgpu/interruptcallback.s
new file mode 100644
index 0000000..8e912d8
--- /dev/null
+++ b/libpsn00b/psxgpu/interruptcallback.s
@@ -0,0 +1,48 @@
+.set noreorder
+
+.include "hwregs_a.h"
+
+.section .text
+
+.global InterruptCallback
+.type InterruptCallback, @function
+InterruptCallback:
+
+	# a0 - Interrupt number
+	# a1 - Callback function
+
+	lui		$a2, IOBASE
+	
+	beqz	$a1, .Ldisable_irq
+	nop
+
+	lw		$v0, IMASK($a2)				# Enable interrupt mask
+	li		$v1, 1
+	sll		$v1, $a0
+	or		$v0, $v1
+
+	b		.Lcont
+	sw		$v0, IMASK($a2)
+	
+.Ldisable_irq:
+
+.set noat
+	lw		$v0, IMASK($a2)				# Disable interrupt mask
+	li		$v1, 1
+	sll		$v1, $a0
+	addiu	$at, $0 , -1
+	xor		$v1, $at
+.set at
+	and		$v0, $v1
+	sw		$v0, IMASK($a2)
+	
+.Lcont:
+
+	la		$a2, _irq_func_table		# Get address to IRQ function table
+	
+	sll		$v1, $a0, 2					# Compute the slot
+	addu	$v1, $a2, $v1
+	lw		$v0, 0($v1)					# Get old handler address
+	
+	jr		$ra							# Return and set new IRQ handler
+	sw		$a1, 0($v1)
diff --git a/libpsn00b/psxgpu/loadimage.s b/libpsn00b/psxgpu/loadimage.s
index 2376b31..4a3b4e0 100644
--- a/libpsn00b/psxgpu/loadimage.s
+++ b/libpsn00b/psxgpu/loadimage.s
@@ -19,7 +19,7 @@ LoadImage:
 
 	lui		$s0, 0x1f80			# Set I/O segment base address
 
-.gpu_wait:						# Wait for GPU to be ready for commands and DMA
+.Lgpu_wait:						# Wait for GPU to be ready for commands and DMA
 	jal		ReadGPUstat
 	nop
 	srl		$v0, 0x1a
@@ -27,7 +27,7 @@ LoadImage:
 	li		$v1, 5
 	#srl		$v0, 28
 	#andi	$v0, 1
-	bne		$v0, $v1, .gpu_wait
+	bne		$v0, $v1, .Lgpu_wait
 	nop
 
 	lui		$v0, 0x400			# Set DMA direction to off
diff --git a/libpsn00b/psxgpu/putdispenv.s b/libpsn00b/psxgpu/putdispenv.s
index 0993e5c..4baa20e 100644
--- a/libpsn00b/psxgpu/putdispenv.s
+++ b/libpsn00b/psxgpu/putdispenv.s
@@ -32,53 +32,53 @@ PutDispEnv:
 
 	move	$a1, $0						# To use as mode value
 
-	bgt		$a2, 560, .mode_640
+	bgt		$a2, 560, .Lmode_640
 	nop
-	bgt		$a2, 400, .mode_512
+	bgt		$a2, 400, .Lmode_512
 	nop
-	bgt		$a2, 352, .mode_384
+	bgt		$a2, 352, .Lmode_384
 	nop
-	bgt		$a2, 280, .mode_320
+	bgt		$a2, 280, .Lmode_320
 	nop
 
 	.set noat
 
-.mode_256:
+.Lmode_256:
 	li		$at, 10
 	mult	$at, $v1
 	li		$a2, 0x24e
 	sll		$v0, 2
 	add		$a2, $v0
-	b		.mode_end
+	b		.Lmode_end
 	li		$v1, 0xa00
-.mode_320:
+.Lmode_320:
 	li		$at, 8
 	mult	$at, $v1
 	li		$a2, 0x258
 	ori		$a1, 0x01
 	sll		$v0, 2
 	add		$a2, $v0
-	b		.mode_end
+	b		.Lmode_end
 	li		$v1, 0xa00
-.mode_384:
+.Lmode_384:
 	li		$at, 7
 	mult	$at, $v1
 	li		$a2, 0x21b
 	ori		$a1, 0x64
 	sll		$v0, 2
 	add		$a2, $v0
-	b		.mode_end
+	b		.Lmode_end
 	li		$v1, 0xa80
-.mode_512:
+.Lmode_512:
 	li		$at, 5
 	mult	$at, $v1
 	li		$a2, 0x267
 	ori		$a1, 0x02
 	sll		$v0, 2
 	add		$a2, $v0
-	b		.mode_end
+	b		.Lmode_end
 	li		$v1, 0xa00
-.mode_640:
+.Lmode_640:
 	li		$at, 4
 	mult	$at, $v1
 	li		$a2, 0x26c
@@ -86,15 +86,15 @@ PutDispEnv:
 	sll		$v0, 2
 	add		$a2, $v0
 	li		$v1, 0xa00
-.mode_end:
+.Lmode_end:
 
 	.set at
 
 	mflo	$v0
-	bnez	$v0, .no_default			# Check if screen with is non zero
+	bnez	$v0, .Lno_default			# Check if screen with is non zero
 	nop
 	move	$v0, $v1					# Use default if screen width is 0
-.no_default:
+.Lno_default:
 
 	addu	$v0, $a2					# Apply horizontal display coordinates
 	sll		$v0, 12
@@ -108,19 +108,19 @@ PutDispEnv:
 
 	lh		$v0, DISP_dh($a0)
 	li		$a2, 0x10
-	ble		$v0, 256, .mode_low
+	ble		$v0, 256, .Lmode_low
 	nop
 
-.mode_high:
+.Lmode_high:
 	ori		$a1, 0x04
-.mode_low:
+.Lmode_low:
 	lh		$v0, DISP_sy($a0)
 	lh		$v1, DISP_sh($a0)
 	add		$a2, $v0
-	bnez	$v1, .no_default_vert
+	bnez	$v1, .Lno_default_vert
 	nop
 	li		$v1, 0xf0
-.no_default_vert:
+.Lno_default_vert:
 	add		$v1, $a2
 	and		$a2, 0x3ff
 	sll		$v1, 10
@@ -134,28 +134,28 @@ PutDispEnv:
 	la		$v0, _gpu_standard
 	lbu		$v0, 0($v0)
 	nop
-	beqz	$v0, .config_ntsc
+	beqz	$v0, .Lconfig_ntsc
 	nop
-.config_pal:
+.Lconfig_pal:
 	ori		$a1, 0x08
-.config_ntsc:
+.Lconfig_ntsc:
 
 	lbu		$v0, DISP_inter($a0)
 	lbu		$v1, DISP_isrgb24($a0)
-	beqz	$v0, .no_inter
+	beqz	$v0, .Lno_inter
 	nop
 	or		$a1, 0x20
-.no_inter:
-	beqz	$v1, .no_rgb24
+.Lno_inter:
+	beqz	$v1, .Lno_rgb24
 	nop
 	or		$a1, 0x10
-.no_rgb24:
+.Lno_rgb24:
 	lbu		$v0, DISP_inter($a0)
 	nop
-	beqz	$v0, .no_reverse
+	beqz	$v0, .Lno_reverse
 	nop
 	or		$a1, 0x80
-.no_reverse:
+.Lno_reverse:
 
 	lui		$v0, 0x800					# Apply mode
 	or		$a1, $v0
diff --git a/libpsn00b/psxgpu/putdrawenv.s b/libpsn00b/psxgpu/putdrawenv.s
index 69af437..c0d5676 100644
--- a/libpsn00b/psxgpu/putdrawenv.s
+++ b/libpsn00b/psxgpu/putdrawenv.s
@@ -97,7 +97,7 @@ PutDrawEnv:
 
 	lbu		$v0, DRAW_isbg($a0)
 	nop
-	beqz	$v0, .no_fillVRAM
+	beqz	$v0, .Lno_fillVRAM
 	nop
 
 	lw		$v0, DRAW_isbg($a0)			# FillVRAM
@@ -110,7 +110,7 @@ PutDrawEnv:
 	sw		$v0, 24($a1)				# 6
 
 	srl		$v0, $v1, 16				# Workaround as rectangle primitives
-	blt		$v0, 511, .no_overflow		# don't accept a height of 512
+	blt		$v0, 511, .Lno_overflow		# don't accept a height of 512
 	nop
 
 	li		$v0, 511
@@ -118,19 +118,19 @@ PutDrawEnv:
 	andi	$v1, 0xffff
 	or		$v1, $v0
 
-.no_overflow:
+.Lno_overflow:
 	sw		$v1, 28($a1)				# 7
 	li		$v0, 0x07ffffff				# Packet header (length+terminator)
 	sw		$v0, 0($a1)
 
-.no_fillVRAM:
+.Lno_fillVRAM:
 
-.gpu_wait:								# Wait for GPU to become ready for commands and DMA
+.Lgpu_wait:								# Wait for GPU to become ready for commands and DMA
 	jal		ReadGPUstat
 	nop
 	srl		$v0, 26
 	andi	$v0, 1
-	beqz	$v0, .gpu_wait
+	beqz	$v0, .Lgpu_wait
 	nop
 
 	jal		DrawOTag
diff --git a/libpsn00b/psxgpu/readme.txt b/libpsn00b/psxgpu/readme.txt
index 0d44e72..8fe439b 100644
--- a/libpsn00b/psxgpu/readme.txt
+++ b/libpsn00b/psxgpu/readme.txt
@@ -23,39 +23,7 @@ Library header(s):
 
 Todo list:
 
-	* VSync() and DrawSync() functions lack alternate operating modes such as
-	  getting number of vsyncs elapsed and waiting until a specified number of
-	  vsyncs have passed.
-
-	* (old) VSync interrupt handler should be hooked using BIOS function
-	  SetCustomExitFromException() like the official GPU library instead of
-	  hooking an event handler, but said hook never seems to work. Perhaps
-	  something in the kernel area needs to be patched/set or some event/IRQ
-	  handler needs to be removed as such handlers can skip the custom
-	  exception exit entirely.
-	  
-	  It also appears that all interrupt handling in the official libraries
-	  are done through the GPU library. This would also explain why the
-	  official documentation tells you to always call ResetGraph() at the
-	  very beginning of your programs.
-
 	* ClearOTag() function (non reverse version of ClearOTagR()) yet to be
-	  implemented.
+	  implemented (but should be trivial).
 	  
 	* StoreImage() equivalent yet to be implemented.
-
-
-Changelog:
-
-	05-23-2019 by Lameguy64:
-	
-	* Got custom exit handler set using SetCustomExitFromException() (BIOS
-	  function B(19h)) working. Currently used to acknowledge VSync IRQ but
-	  actual VSync handling is still done with events and needs to be
-	  transferred to the custom exit handler. At least it lets BIOS
-	  controller functions to work now. See doc/dev notes.txt for details
-	  on how this handler behaves.
-	
-	* Made stack usage a lot less wasteful in ResetGraph() (you only need
-	  to allocate N words on stack based on N arguments of the function
-	  being called.
diff --git a/libpsn00b/psxgpu/resetgraph.s b/libpsn00b/psxgpu/resetgraph.s
index 189b1ad..ff0b353 100644
--- a/libpsn00b/psxgpu/resetgraph.s
+++ b/libpsn00b/psxgpu/resetgraph.s
@@ -1,5 +1,4 @@
 .set noreorder
-.set noat
 
 .include "hwregs_a.h"
 
@@ -16,21 +15,7 @@ ResetGraph:
 	la		$v0, _hooks_installed		# Skip installing hooks if this function
 	lbu		$v0, 0($v0)					# has already been called before once
 	nop
-	bnez	$v0, .skip_hook_init
-	nop
-
-	# Temporary, may help improve compatibility?
-	#jal		SetDefaultExitFromException
-	#nop
-
-	jal		ChangeClearPAD				# Remove pad handler left by the BIOS
-	move	$a0, $0
-
-	li		$a0, 1
-	jal		ChangeClearRCnt				# Remove RCnt handler
-	move	$a1, $0
-
-	jal		_96_remove					# Remove CD handling left by the BIOS
+	bnez	$v0, .Lskip_hook_init
 	nop
 
 	lui		$a3, 0x1f80					# Base address for I/O
@@ -40,48 +25,51 @@ ResetGraph:
 	sw		$v0, DPCR($a3)
 	sw		$0 , DICR($a3)				# Clear DICR (not needed)
 
-	li		$v0, 0x9					# Enable IRQ0 (vblank)
-	sw		$v0, IMASK($a3)
-
-	# Set an event handler
-
-	li		$a0, 0xf2000003				# RCntCNT3 (vsync class)
-	li		$a1, 0x2
-	li		$a2, 0x1000
-	la		$a3, _vsync_func			# VSync event handler
-
-	jal		OpenEvent					# Open a VSync event handler
-										# (PSXSDK style vsync handler)
-	addiu	$sp, -16
-	addiu	$sp, 16
-
-	la		$v1, _vsync_event_desc		# Save event descriptor
-	sw		$v0, 0($v1)
-
-	move	$a0, $v0
-	jal		EnableEvent					# Enable the opened event
-	addiu	$sp, -4
-	addiu	$sp, 4
-
+	sw		$0 , IMASK($a3)				# Clear IRQ settings
+	
 	la		$v0, _hooks_installed		# Set installed flag
 	li		$v1, 0x1
 	sb		$v1, 0($v0)
 
-	la		$v0, _vsync_counter			# Clear VSync counter
+	la		$v0, _vsync_cb_func			# Clear VSync callback function
 	sw		$0 , 0($v0)
 
-	la		$v0, _vsync_callback_func	# Clear callback function
-	sw		$0 , 0($v0)
-
-	la		$a0, _custom_exit
+	la		$a1, _vsync_irq_callback	# Install VSync interrupt callback
+	jal		InterruptCallback
+	li		$a0, 0
+	
+	la		$a0, _custom_exit			# Set custom exit handler
 	jal		SetCustomExitFromException
 	addiu	$sp, -4
 	addiu	$sp, 4
 	
+	move	$a0, $0
+	jal		ChangeClearPAD				# Disable VSync IRQ auto ack
+	addiu	$sp, -4
+	addiu	$sp, 4
+
+	li		$a0, 3
+	move	$a1, $0
+	jal		ChangeClearRCnt				# Remove RCnt timer IRQ auto ack
+	addiu	$sp, -8
+	addiu	$sp, 8
+
+	jal		_96_remove					# Remove CD handling left by the BIOS
+	nop
+	
+	la		$a0, resetgraph_msg
+	move	$a1, $0
+	move	$a2, $0
+	la		$a1, _irq_func_table
+	la		$a2, _custom_exit
+	jal		printf
+	addiu	$sp, -16
+	addiu	$sp, 16
+	
 	jal		ExitCriticalSection			# Re-enable interrupts
 	nop
-
-.skip_hook_init:
+	
+.Lskip_hook_init:
 	
 	lui		$a3, 0x1f80
 
@@ -89,42 +77,40 @@ ResetGraph:
 	lui		$v1, 0x0010
 	and		$v0, $v1
 	la		$v1, _gpu_standard
-	beqz	$v0, .not_pal
+	beqz	$v0, .Lnot_pal
 	sw		$0 , 0($v1)
 	li		$v0, 1
 	sw		$v0, 0($v1)
-.not_pal:
+.Lnot_pal:
 
-	lw		$a0, 4($sp)				# Get argument value
+	lw		$a0, 4($sp)					# Get argument value
 
 	lui		$a3, 0x1f80					# Set base I/O again (likely destroyed
 										# by previous calls)
 
 	li		$v0, 0x1d00					# Configure timer 1 as Hblank counter
 	sw		$v0, T1_MODE($a3)			# Set timer 1 value
-
-	li		$at, 1
-	beq		$a0, $at, .gpu_init_1
+	
+	beq		$a0, 1, .Lgpu_init_1
 	nop
-	li		$at, 3
-	beq		$a0, $at, .gpu_init_3
+	beq		$a0, 3, .Lgpu_init_3
 	nop
 
 	sw		$0 , GP1($a3)				# Reset the GPU
 
-	b		.init_done
+	b		.Linit_done
 	nop
 
-.gpu_init_1:
+.Lgpu_init_1:
 
 	sw		$0 , D2_CHCR($a3)			# Stop any DMA
 
-.gpu_init_3:
+.Lgpu_init_3:
 
 	li		$v0, 0x1					# Reset the command buffer
 	sw		$v0, GP1($a3)
 
-.init_done:
+.Linit_done:
 
 	lw		$ra, 0($sp)
 	lw		$a0, 4($sp)					# Return
@@ -132,147 +118,312 @@ ResetGraph:
 	addiu	$sp, 8
 
 
-.global _vsync_func						# VSync event handler, executed on
-.type _vsync_func, @function			# every VBlank
-_vsync_func:
-
-	la		$gp, _gp
-
-	lui		$at, 0x1f80					# Check if there's a VSync IRQ
-	lw		$v0, IMASK($at)
+.global VSync							# VSync function
+.type VSync, @function
+VSync:
+	
+	addiu	$sp, -12
+	sw		$ra, 0($sp)
+	sw		$s0, 4($sp)
+	
+	lui		$a3, IOBASE					# Get GPU status (for interlace sync)
+	lw		$s0, GP1($a3)
+	
+.Lhwait_loop:							# Get Hblank time
+	lw		$v0, T1_CNT($a3)
+	nop
+	lw		$v1, T1_CNT($a3)
 	nop
-	andi	$v0, $v0, 0x1
-	beqz	$v0, .exit
+	bne		$v0, $v1, .Lhwait_loop
 	nop
+	
+	la		$a3, _vsync_lasthblank		# Calculate Hblank time since last
+	lw		$v1, 0($a3)
+	nop
+	subu	$v0, $v1
+	andi	$v0, 0xffff
+	
+	beq		$a0, 1, .Lhblank_exit		# Return Hblank time only, no VSync
+	sw		$v0, 8($sp)					# Stored as return value
+	
+	bgez	$a0, .Lvsync				# Vsync if argument is 0 and up
+	nop
+	
+	la		$v0, _vsync_rcnt			# Return VSync count only
+	lw		$v0, 0($v0)
+	nop
+	b		.Lvsync_exit
+	sw		$v0, 8($sp)
+	
+.Lvsync:
 
-	lw		$v1, ISTAT($at)
+	bnez	$a0, .Lnot_zero
 	nop
-	andi	$v0, $v1, 0x1
-	beqz	$v0, .exit
+	li		$a0, 1
+	
+.Lnot_zero:
+	
+	la		$v0, _vsync_rcnt			# Call vsync sub function (with timeout)
+	lw		$v0, 0($v0)
+	addiu	$a1, $a0, 1
+	jal		_vsync_sub
+	addu	$a0, $v0, $a0
+	
+	lui		$v0, 0x40
+	and		$v0, $s0, $v0
+	beqz	$v0, .Lhblank_exit
+	nop
+	
+	lui		$a3, IOBASE					# Interlace wait logic
+	
+	lw		$v0, GP1($a3)
+	nop
+	xor		$v0, $s0, $v0
+	bltz	$v0, .Lhblank_exit
+	lui		$a0, 0x8000
+	
+.Linterlace_wait:
+	lw		$v0, GP1($a3)
+	nop
+	xor		$v0, $s0, $v0
+	and		$v0, $a0
+	beqz	$v0, .Linterlace_wait
 	nop
 	
-	#xori	$v1, $v1, 0x1				# Acknowledge the IRQ
-	#sw		$v1, ISTAT($at)				# Commented out as it breaks BIOS pads
+.Lhblank_exit:							# Set current Hblank as last value
 
-	la		$v1, _vsync_counter			# Increment VSync counter
-	lw		$v0, 0($v1)
+	la		$a2, _vsync_lasthblank
+	
+.Lhwait2_loop:
+	lw		$v0, T1_CNT($a3)
+	nop
+	lw		$v1, T1_CNT($a3)
+	sw		$v0, 0($a2)
+	bne		$v0, $v1, .Lhwait2_loop
 	nop
-	addiu	$v0, 1
-	sw		$v0, 0($v1)
 
-	la		$v0, _vsync_callback_func	# Check if a callback function is set
+.Lvsync_exit:
+
+	lw		$ra, 0($sp)
+	lw		$s0, 4($sp)
+	lw		$v0, 8($sp)
+	jr		$ra
+	addiu	$sp, 12
+
+	
+.type _vsync_sub, @function	
+_vsync_sub:
+
+	# a0 - VSync destination count
+	# a1 - Timeout ratio (number of vsyncs to wait relative to vsync count)
+
+	addiu	$sp, -4
+	sw		$ra, 0($sp)
+
+	sll		$a1, 15						# Timeout counter
+	
+	la		$v0, _vsync_rcnt
 	lw		$v0, 0($v0)
 	nop
-	beqz	$v0, .exit
+	bge		$v0, $a0, .Lvsync_sub_exit
 	nop
+	
+.Lvsync_wait:
 
-	addiu	$sp, -0x20					# Save return address
-	sw		$ra, 28($sp)
-
-	jalr	$v0							# Execute user function
+	addiu	$a1, -1
+	
+	la		$v1, 0xffffffff
+	bne		$a1, $v1, .Lnot_timeout
 	nop
 
-	lw		$ra, 28($sp)				# Restore previous return address
-	addiu	$sp, 0x20
+	la		$a0, vsynctimeout_msg
+	jal		puts
+	addiu	$sp, -8
+	
+	jal		ChangeClearPAD
+	move	$a0, $0
+	
+	li		$a0, 3
+	jal		ChangeClearRCnt
+	move	$a1, $0
+	
+	addiu	$sp, 8
+	b		.Lvsync_sub_exit
+	li		$v0, -1
+	
+.Lnot_timeout:
 
-.exit:
-	jr      $ra
+	la		$v0, _vsync_rcnt
+	lw		$v0, 0($v0)
+	nop
+	blt		$v0, $a0, .Lvsync_wait
 	nop
+	
+.Lvsync_sub_exit:
+
+	lw		$ra, 0($sp)
+	addiu	$sp, 4
+	jr		$ra
+	move	$v0, $0
 
 
-.global _vsync_func_2
-.type _vsync_func_2, @function
-_vsync_func_2:
 	
-	lui		$at, 0x1f80					# Check if there's a VSync IRQ
-	lw		$v0, IMASK($at)
-	nop
-	andi	$v0, $v0, 0x1
-	beqz	$v0, .exit_2
+.type _vsync_irq_callback, @function
+_vsync_irq_callback:
+	
+	lui		$a0, IOBASE
+	
+	la		$v1, _vsync_rcnt			# Increment VSync root counter
+	lw		$v0, 0($v1)
 	nop
+	addiu	$v0, 1
+	sw		$v0, 0($v1)
 
-	lw		$v1, ISTAT($at)
+	la		$v0, _vsync_cb_func			# Check if a callback function is set
+	lw		$v0, 0($v0)
 	nop
-	andi	$v0, $v1, 0x1
-	beqz	$v0, .exit_2
+	beqz	$v0, .Lno_callback
 	nop
 	
-	xori	$v1, $v1, 0x1				# Acknowledge the IRQ
-	sw		$v1, ISTAT($at)
-
-.exit_2:
+	addiu	$sp, -4						# Save return address
+	sw		$ra, 0($sp)
+	jalr	$v0							# Execute user callback function
+	nop
+	lw		$ra, 0($sp)					# Restore previous return address
+	addiu	$sp, 4
 	
-	j		ReturnFromException
+	lui		$a0, IOBASE
+	
+.Lno_callback:
+
+	jr		$ra
 	nop
+	
 
+# Global ISR handler of PSn00bSDK
 
-.global VSync							# VSync function
-.type VSync, @function
-VSync:
-	addiu	$sp, -4
-	sw		$ra, 0($sp)
+.set at
+
+.type _global_isr, @function
+_global_isr:
+
+	lui		$a0, IOBASE					# Get IRQ status
+	
+.Lisr_loop:
 
-	la		$a1, _vsync_counter
-	lw		$v0, 0($a1)
+	lui		$a0, IOBASE					# Get IRQ status
+	lw		$v0, IMASK($a0)
 	nop
-.loop:
-	lw		$v1, 0($a1)
+	
+	srl		$v0, $s1					# Check IRQ mask bit if set
+	andi	$v0, 0x1
+	
+	beqz	$v0, .Lno_irq				# Don't execute callback if IRQ not enabled
 	nop
-	beq		$v0, $v1, .loop
+	
+	lw		$v0, ISTAT($a0)
 	nop
-
-	la		$v0, _gpu_current_field		# Get last field value
-	lbu		$v1, 0($v0)
-.wait_field:							# Wait for field bit to change
-	jal		ReadGPUstat
+	srl		$v0, $s1					# Check IRQ status bit if set
+	andi	$v0, 0x1
+	beqz	$v0, .Lno_irq				# Don't execute callback if no IRQ
 	nop
-	srl		$v0, 31
-	beq		$v0, $v1, .wait_field
+	
+	lw		$v1, 0($s0)					# Load IRQ callback function
+	nop
+	
+	lw		$v0, ISTAT($a0)				# Acknowledge the IRQ (by writing a 0 bit)
+	li		$a1, 1
+	sll		$a1, $s1
+	addiu	$a2, $0 , -1
+	xor		$a1, $a2
+	sw		$a1, ISTAT($a0)
+	
+	beqz	$v1, .Lno_irq				# Don't execute if callback is not set
 	nop
 
-	la		$v1, _gpu_current_field		# Store new field value
-	sb		$v0, 0($v1)
-
-	lw		$ra, 0($sp)
-	addiu	$sp, 4
-	jr		$ra
+	jalr	$v1							# Call interrupt handler
 	nop
+	
+.Lno_irq:
+
+	addiu	$s0, 4
+	
+	blt		$s1, 11, .Lisr_loop
+	addiu	$s1, 1
 
+	j		ReturnFromException
+	nop
+	
 
 .section .data
 
-.global library_credits
-.type library_credits, @object
-library_credits:
-	.string "psxgpu programs by Lameguy64"
+# VSync root counter
+.type _vsync_rcnt, @object
+_vsync_rcnt:
+	.word 0
+
+.type _vsync_lasthblank, @object
+_vsync_lasthblank:
+	.word 0
+	
+.comm	_vsync_cb_func, 4, 4
+
+.comm	_gpu_standard, 4, 4
+.comm	_gpu_current_field, 4, 4
+.comm	_hooks_installed, 4, 4
 
 
+# Global ISR callback table
+
+.global _irq_func_table
+.type _irq_func_table, @object
+_irq_func_table:
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+	.word	0
+
+# Global ISR hook structure
 .type _custom_exit, @object
 _custom_exit:
-	.word _vsync_func_2		# pc
-	.word _vsync_stack		# sp
-	.word 0					# fp
-	.word 0					# s0
-	.word 0					# s1
-	.word 0					# s2
-	.word 0					# s3
-	.word 0					# s4
-	.word 0					# s5
-	.word 0					# s6
-	.word 0					# s7
-	.word _gp				# gp
-
-	.fill 60
-_vsync_stack:
+	.word _global_isr			# pc
+	.word _custom_exit_stack	# sp
+	.word 0						# fp
+	.word _irq_func_table		# s0
+	.word 0						# s1
+	.word 0						# s2
+	.word 0						# s3
+	.word 0						# s4
+	.word 0						# s5
+	.word 0						# s6
+	.word 0						# s7
+	.word _gp					# gp
+	
+# Global ISR stack
+	.fill 124
+_custom_exit_stack:
 	.fill 4
 	
-.type _vsync_counter, @object
-_vsync_counter:
-	.word 0
-
-.comm	_vsync_callback_func, 4, 4
-.comm	_vsync_event_desc, 4, 4
+	
+.type vsynctimeout_msg, @object
+vsynctimeout_msg:
+	.asciiz "VSync: timeout\n"
 
-.comm	_gpu_standard, 4, 4
-.comm	_gpu_current_field, 4, 4
-.comm	_hooks_installed, 4, 4
+.type resetgraph_msg, @object
+resetgraph_msg:
+	.asciiz "ResetGraph:itb=%08x,ehk=%08x\n"
+	
+.global psxgpu_credits
+.type psxgpu_credits, @object
+psxgpu_credits:
+	.ascii "psxgpu programs by Lameguy64\n"
+	.asciiz "2019 PSn00bSDK Project / Meido-Tek Productions\n"
+	
\ No newline at end of file
diff --git a/libpsn00b/psxgpu/setvideomode.s b/libpsn00b/psxgpu/setvideomode.s
index 718a4dd..4395f0a 100644
--- a/libpsn00b/psxgpu/setvideomode.s
+++ b/libpsn00b/psxgpu/setvideomode.s
@@ -30,13 +30,13 @@ SetVideoMode:
 	andi	$a1, 0xf7				# Mask off PAL bit
 
 	la		$v0, _gpu_standard
-	beqz	$a0, .set_done
+	beqz	$a0, .Lset_done
 	sw		$0 , 0($v0)
 	li		$v1, 1
 	sw		$v1, 0($v0)
-	b		.set_done
+	b		.Lset_done
 	or		$a1, 0x8
-.set_done:
+.Lset_done:
 
 	lui		$v0, 0x800				# Apply new mode
 	or		$a1, $v0
diff --git a/libpsn00b/psxgpu/vsynccallback.s b/libpsn00b/psxgpu/vsynccallback.s
index 1f96bbc..4be29c8 100644
--- a/libpsn00b/psxgpu/vsynccallback.s
+++ b/libpsn00b/psxgpu/vsynccallback.s
@@ -12,7 +12,7 @@ VSyncCallback:
 	sw		$a0, 4($sp)
 
 	lw		$a0, 4($sp)
-	la		$v0, _vsync_callback_func
+	la		$v0, _vsync_cb_func
 	sw		$a0, 0($v0)
 
 	jal		ExitCriticalSection