cleaned up codehandler to allow for better changes later

1 files changed, 368 insertions, 0 deletions

diff --git a/src/codehandler.s b/src/codehandler.s
new file mode 100644
index 0000000..bf9ce13
--- /dev/null
+++ b/src/codehandler.s
@@ -0,0 +1,368 @@
+.text

+

+#ifndef __MWERKS__

+.set r0,0;   .set r1,1;   .set r2,2;   .set r3,3;   .set r4,4

+.set r5,5;   .set r6,6;   .set r7,7;   .set r8,8;   .set r9,9

+.set r10,10; .set r11,11; .set r12,12; .set r13,13; .set r14,14

+.set r15,15; .set r16,16; .set r17,17; .set r18,18; .set r19,19

+.set r20,20; .set r21,21; .set r22,22; .set r23,23; .set r24,24

+.set r25,25; .set r26,26; .set r27,27; .set r28,28; .set r29,29

+.set r30,30; .set r31,31; .set f0,0;   .set f2,2;   .set f3,3

+#endif

+	 

+.extern frozen_value

+.extern regbuffer

+.extern bpbuffer

+.extern command_handler__Fv

+.extern get_frozenvalue__Fv

+.extern exisendbyte__FUc

+

+.extern OSReport

+

+.globl _start

+

+gameid:

+.long	0,0

+cheatdata:

+.long	frozenvalue

+.space 39*4

+

+_start:

+	stwu	r1,-168(r1)		# stores sp

+	stw		r0,8(r1)		# stores r0

+

+	mflr	r0

+	stw		r0,172(r1)		# stores lr

+

+	mfcr	r0

+	stw		r0,12(r1)		# stores cr

+

+	mfctr	r0

+	stw		r0,16(r1)		# stores ctr

+

+	mfxer	r0

+	stw		r0,20(r1)		# stores xer

+

+	stmw	r3,24(r1)		# saves r3-r31

+

+	mfmsr	r25

+	ori		r26,r25,0x2000	#enable floating point ?

+	andi.	r26,r26,0xF9FF

+	mtmsr	r26

+

+

+	stfd	f2,152(r1)		# stores f2

+	stfd	f3,160(r1)		# stores f3

+

+

+    lis		r20, 0xCC00

+    lhz		r28, 0x4010(r20)

+    ori		r21, r28, 0xFF

+    sth		r21, 0x4010(r20) # disable MP3 memory protection

+

+_setvalues:

+	li		r21,0

+	li		r22,0x19

+	li		r23,0xD0

+	lis		r24,0xCD00

+

+	lis		r18, frozenvalue@h

+	ori		r18, r18, frozenvalue@l	# read buffer just store in lowmem

+	lwz		r0,172(r1)				# loads lr

+	stw		r0,4(r18)				# stores lr

+    stw		r21, 0x643C(r24)		# exi speed up

+

+_check_frozen:

+	lis		r18, frozen_value@h

+	ori		r18, r18, frozen_value@l

+	lwz		r0, 0x0(r18)

+	cmpwi	r0, 2

+	bne		frozen

+#TESTING FOR EXECUTION

+	lis		r3, stringer@h

+	ori		r3, r3, stringer@l

+	bl		OSReport

+

+

+frozen:

+	bl		command_handler__Fv

+	cmpwi	r3, 0

+	beq		resumegame

+	b		finish

+

+#******************************************************************

+#                        subroutine: bphandler

+#    Data/Instruction address breakpoint handler, save context and return

+#******************************************************************

+.global bphandler

+bphandler:

+	mtsprg	0, r3

+	lis		r3, regbuffer@h

+	ori		r3, r3, regbuffer@l

+	stmw	r4, 0x2C(r3)				# Store r4 - r31

+

+	stw		r0, 0x1C(r3)				# Store r0

+	stw		r1, 0x20(r3)				# Store r1

+	stw		r2, 0x24(r3)				# Store r2

+	mr		r4, r3

+	mfsprg	r3, 0

+	stw		r3, 0x28(r4)				# Store r3

+

+	mfsrr1	r3

+	rlwinm	r3, r3,0,22,20				# clear trace

+	stw		r3, 0x18(r4)				# Store SRR1

+	rlwinm	r3, r3,0,24,15

+	ori		r3, r3,0x2000

+#	rlwinm	r3, r3,0,17,15				# clear hw interrupt

+	mtsrr1	r3							# restore srr1 with hw interrupt & trace cleared

+

+	mfsrr0	r3

+	stw		r3, 0x14(r4)				# Store SRR0

+

+	mflr	r3

+	stw		r3, 0x9C(r4)				# Store LR

+

+	mfcr	r3

+	stw		r3, 0x0(r4)					# Store CR

+

+	mfxer	r3

+	stw		r3, 0x4(r4)					# Store XER

+

+	mfctr	r3

+	stw		r3, 0x8(r4)					# Store CTR

+

+	mfdsisr	r3

+	stw		r3, 0xC(r4)					# Store DSISR

+       

+	mfdar	r3

+	stw		r3, 0x10(r4)				# Store DAR

+

+	lis		r3, break@h

+	ori		r3, r3, break@l

+	mtsrr0	r3

+	rfi

+

+break:

+	li		r3, 0

+	mtspr	1010, r3					# Clear IABR

+	mtspr	1013, r3					# Clear DABR

+

+#BACKUP FPR

+	lis		r4, regbuffer@h

+	ori		r4, r4, regbuffer@l

+	stfs	f0, 0xA0(r4)

+	stfs	f1, 0xA4(r4)

+	stfs	f2, 0xA8(r4)

+	stfs	f3, 0xAC(r4)

+	stfs	f4, 0xB0(r4)

+	stfs	f5, 0xB4(r4)

+	stfs	f6, 0xB8(r4)

+	stfs	f7, 0xBC(r4)

+	stfs	f8, 0xC0(r4)

+	stfs	f9, 0xC4(r4)

+	stfs	f10, 0xC8(r4)

+	stfs	f11, 0xCC(r4)

+	stfs	f12, 0xD0(r4)

+	stfs	f13, 0xD4(r4)

+	stfs	f14, 0xD8(r4)

+	stfs	f15, 0xDC(r4)

+	stfs	f16, 0xE0(r4)

+	stfs	f17, 0xE4(r4)

+	stfs	f18, 0xE8(r4)

+	stfs	f19, 0xEC(r4)

+	stfs	f20, 0xF0(r4)

+	stfs	f21, 0xF4(r4)

+	stfs	f22, 0xF8(r4)

+	stfs	f23, 0xFC(r4)

+	stfs	f24, 0x100(r4)

+	stfs	f25, 0x104(r4)

+	stfs	f26, 0x108(r4)

+	stfs	f27, 0x10C(r4)

+	stfs	f28, 0x110(r4)

+	stfs	f29, 0x114(r4)

+	stfs	f30, 0x118(r4)

+	stfs	f31, 0x11C(r4)

+

+#TESTING FOR EXECUTION

+#	lis		r3, stringer@h

+#	ori		r3, r3, stringer@l

+#	bl		OSReport

+

+# r4=regbuffer, r=bpbuffer

+# r16=instBp, r17=dataBp, r19=lastBp

+

+#HANDLE MORE STUFF

+	lis		r5, bpbuffer@h

+	ori		r5, r5, bpbuffer@l

+

+	lwz		r16, 0x0(r5)			# inst bp

+	lwz		r17, 0x4(r5)			# data bp

+	lwz		r19, 0xC(r5)			# last break address

+

+	cmpwi	r19, 0

+	beq		_redobp					# last break was 0. redo bp

+

+	cmpwi	r19, 2

+	bne		addr_1

+	lwz		r9, 0x14(r4)			# SRR0

+	addi	r9, r19, 3

+	stw		r9, 0x0(r5)				# inst bp

+	stw		r9, 0xC(r5)				# last broken on address

+	b		_executebp

+

+addr_1:

+	cmpw	r16, r19

+	beq		_step

+

+	cmpw	r17, r19

+	beq		_step

+

+	add		r9, r16, r17

+	stw		r9, 0xC(r5)		# counter for alignment

+

+

+_alignementcheck:

+	lwz		r16, 0x8(r5)	# bp alignment check

+	cmpwi	r16, 0

+	beq		_executebp		# no alignement = normal break

+

+	lwz		r3, 0x10(r4)	# DAR

+	cmpw	r16, r3			# we check if address = aligned address

+	bne		_step			# if no, we need to set a bp on the next instruction

+

+	li		r16, 0

+	stw		r16, 0x8(r5)	# if we are on the good address we clear the aligned bp check

+	b		_executebp		# and we break

+

+_step:

+	li		r17, 0

+	stw		r17, 0xC(r5)	# we set last broken on address to 0

+	lwz		r9, 0x18(r4)

+	ori		r9, r9, 0x400

+	stw		r9, 0x18(r4)	# SRR1 |= 0x400

+	b		_skipbp			# and we don't break right now

+

+_redobp:

+	mtspr	1010, r16		# we set back the instbp with the original value

+	mtspr	1013, r17		# we set back the databp with the original value

+	li		r9, 1

+	stw		r9, 0xC(r5)		# we set last broken on address to 1

+	b		_skipbp			# and we don't break

+

+_executebp:

+#	lis		r1, temp_stack@h

+#	ori		r1, r1, temp_stack@l	# setup temp stack

+	lis		r4, frozen_value@h

+	ori		r4, r4, frozen_value@l

+	li		r5, 2

+	stw		r5, 0x0(r4)		# Freeze once returned to let user know there is a breakpoint hit

+

+	li		r3, 0x11

+	bl		exisendbyte__FUc		# tell the PC a bp has happened (send 0x11)

+

+	bl		_start			# bl mainloop, so you can set up a new breakpoint.

+

+_skipbp:

+	mfmsr	r1

+	rlwinm	r1,r1,0,31,29

+	rlwinm	r1,r1,0,17,15

+	mtmsr	r1				# we disable the interrupt so nothing interfers with the restore

+

+	lis		r1, regbuffer@h

+	ori		r1, r1, regbuffer@l

+

+	lwz		r3,0x0(r1)

+	mtcr	r3				# restores CR

+	lwz		r3,0x14(r1)

+	mtsrr0	r3				# restores SRR0

+	lwz		r3,0x18(r1)

+	mtsrr1	r3				# restores SRR1

+	lwz		r3,0x9C(r1)

+	mtlr	r3				# restores LR

+

+	lmw		r2,0x24(r1)		# restores r2-r31

+

+	lwz		r0,0x1C(r1)		# restores r0

+	lwz		r1,0x20(r1)		# restores r1

+

+	rfi						# back to the game

+

+

+#******************************************************************

+#                Finish

+#		Check if the gecko has been paused. if no return to game

+#******************************************************************

+

+finish:

+	bl get_frozenvalue__Fv

+	cmpwi	r3, 0			# check to see if we have frozen the game

+	bne	frozen				# loop around if we have

+							# (changed to return for the bp)

+

+resumegame:

+

+    sth		r28,0x4010(r20) # restore memory protection value

+

+	lfd		f2,152(r1)		# loads f2

+	lfd		f3,160(r1)		# loads f3

+

+	mtmsr	r25

+

+	lwz		r0,172(r1)

+	mtlr	r0				# restores lr

+

+	lwz		r0,12(r1)

+	mtcr	r0				# restores cr

+

+	lwz		r0,16(r1)

+	mtctr	r0				# restores ctr

+

+	lwz		r0,20(r1)

+	mtxer	r0				# restores xer

+

+	lmw		r3,24(r1)		# restores r3-r31

+

+	lwz		r0,8(r1)		# loads r0

+

+	addi	r1,r1,168

+

+	isync

+

+	blr				# return back to game

+

+#******************************************************************

+#                        Write branch

+#    r3 - source (our mastercode location)

+#    r4 - destination (lowmem area 0x80001800 address which will branch to

+#******************************************************************

+.global writebranch

+writebranch:

+	subf	r6, r3, r4		# subtract r3 from r4 and place in r17

+	lis	r5, 0x4800		# 0x48000000

+	rlwimi	r5,r6,0,6,29

+	stw	r5, 0(r3)		# result in r3

+	

+	dcbf    r0, r3		# data cache block flush

+	sync

+	icbi    r0, r3

+	isync

+

+	blr				# return

+

+#==================================================================

+       

+frozenvalue:	#frozen value, then LR

+.long	0,0

+command:

+.byte 0,0,0,0

+

+.align 4

+.long 0

+stringer:

+.ascii	"I found a codez 1\n"

+stringer2:

+.ascii	"I found a codez 2\n"

+stringer3:

+.ascii	"I found a codez 3\n"

+.end

+