DSP: Comment the DSPSpy ucode a bit.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@2997 8ced0084-cf51-0410-be5f-012b33b47a6e

1 files changed, 65 insertions, 57 deletions

diff --git a/Source/DSPSpy/dsp_code.ds b/Source/DSPSpy/dsp_code.ds
index 8fbbe0cf2e..f47fae728c 100644
--- a/Source/DSPSpy/dsp_code.ds
+++ b/Source/DSPSpy/dsp_code.ds
@@ -1,4 +1,6 @@
+; This is the trojan program we send to the DSP from DSPSpy to figure it out.

 

+; A lot of constant definitions.

 DSCR:	equ 0xffc9	; DSP DMA Control Reg

 DSBL:	equ 0xffcb	; DSP DMA Block Length

 DSPA:	equ 0xffcd	; DSP DMA DMEM Address

@@ -65,6 +67,7 @@ REGS_BASE:	equ		0x0f80
 MEM_HI:			equ		0x0f7E

 MEM_LO:			equ		0x0f7F

 

+; CODE STARTS HERE.

 

 ; Interrupt vectors 8 vectors, 2 opcodes each

 

@@ -78,21 +81,22 @@ MEM_LO:			equ		0x0f7F
 	jmp		irq7

 	

 ; Main code at 0x10

-	CW		0x1302

-	CW		0x1303

-	CW		0x1204

-	CW		0x1305

-	CW		0x1306

+	sbset       #0x02

+	sbset       #0x03

+	sbclr       #0x04

+	sbset       #0x05

+	sbset       #0x06

 

 	s40

-	lri		$r12, #0x00ff

-	

+	lri		$CR, #0x00ff

+

+; Why do we have a main label here?	

 main:

 

-	cw		0x8900

-	cw		0x8100	

+	clr         $ACC1

+	clr         $ACC0

 

-; get address of memory dump and copy it

+; get address of memory dump and copy it to DRAM

 

 	call	wait_for_dsp_mbox

 	si		@DMBH, #0x8888

@@ -114,7 +118,7 @@ main:
 	call	do_dma

 

 

-; get address of registers and DMA them to memory

+; get address of registers and DMA them to ram

 

 	call	wait_for_dsp_mbox

 	si		@DMBH, #0x8888

@@ -135,7 +139,7 @@ main:
 	lr		$r1e, @MEM_LO

 	call	do_dma

 

-

+; Read in all the registers from RAM

 

 	lri		$r00, #REGS_BASE+1

 	lrri	$r01, @$r00

@@ -171,27 +175,29 @@ main:
 	lrri	$r1f, @$r00

 	lr		$r00, @REGS_BASE

 

+;  Right here we are at a specific predetermined state.

+;  Ideal environment to try instructions.

+

+;  We can call send_back at any time to send data back to the PowerPC.

+

 	nop

 	nop

 	nop

 	nop

 

+	cw 0x8600

 

+	call	send_back

 	

-	

-		cw 0x8600

+; We're done - currently we only test one opcode, in this case 0x8600.

+; It's possible to test many more in one go - just call send_back after each one.

 

-		call	send_back

-

-		JMP ende

+	jmp ende

 

+; Below here is tons of random leftover test code from whoever last experimented with this.

 

 ;	call dump_memory

-;	call	send_back

-	

-	

-; 0x041e

-;	

+;	call send_back

 

     cw 0x00de 

     cw 0x03f1 

@@ -405,7 +411,7 @@ g_0c65:
     call	send_back

     

 	

-

+; This is where we jump when we're done testing, see above. 

 ende:

 

 	nop

@@ -416,36 +422,42 @@ ende:
 	nop

 	nop

 	

-	

-	

+; We just fall into a loop, playing dead until someone resets the DSP.	

 dead_loop:

 	jmp		dead_loop

 

+; Utility function to do DMA.

+; r1c:r1e - external address.

+; r18     - address in DSP

 do_dma:

 	sr		@DSMAH, $r1c

 	sr		@DSMAL, $r1e

 	sr		@DSPA, $r18

 	sr		@DSCR, $r19

-	sr		@DSBL, $r1a

+	sr		@DSBL, $r1a  ; This kicks off the DMA.

+

+; Waits for said DMA to complete by watching a bit in DSCR.

 wait_dma:

 	LRS		$ACL1, @DSCR

 	andcf	$acl1, #0x0004

 	JLZ		wait_dma

 	RET

 

-

+; This waits for a mail to arrive in the DSP in-mailbox.

 wait_for_dsp_mbox:

 	lrs		$ACL1, @DMBH

 	andcf	$acl1, #0x8000

 	jlz		wait_for_dsp_mbox

 	ret

 

+; This waits for the CPU to grab a mail that we just sent from the DSP.

 wait_for_cpu_mbox:

 	lrs		$ACL1, @cmbh

 	andcf	$acl1, #0x8000

 	jlnz	wait_for_cpu_mbox

 	ret

-	

+

+; IRQ handlers. Not entirely sure what good they do currently.

 irq0:

 	lri		$acl0, #0x0000

 	jmp		irq

@@ -455,7 +467,6 @@ irq1:
 irq2:

 	lri		$acl0, #0x0002

 	jmp		irq

-	

 irq3:

 	lri		$acl0, #0x0003

 	jmp		irq

@@ -463,14 +474,14 @@ irq4:
 	lri		$acl0, #0x0004

 	jmp		irq

 irq5:

-;	jmp finale

+; No idea what this code is doing.

 	s40

 	mrr		$r0d, $r1c

 	mrr		$r0d, $r1e

 	clr		$acc0

 	mrr		$r1e, $r0d

 	mrr		$r1c, $r0d

-	nop

+	nop     ; Or why there's a nop sled here.

 	nop

 	nop

 	nop

@@ -486,7 +497,7 @@ irq6:
 irq7:

 	lri		$acl0, #0x0007

 	jmp		irq

-		

+

 irq:

 	lrs		$ACL1, @DMBH

 	andcf	$acl1, #0x8000

@@ -497,11 +508,9 @@ irq:
 	si		@DIRQ, #0x0001

 	halt

 	

-	

-	

-	

+; DMA:s the current state of the registers back to the PowerPC. To do this,

+; it must write the contents of all regs to DRAM.

 send_back:

-

 	; store registers to reg table

 	sr		@REGS_BASE,  $r00

 	lri		$r00, #(REGS_BASE + 1)

@@ -536,8 +545,8 @@ send_back:
 	srri	@$r00, $r1d

 	srri	@$r00, $r1e

 	srri	@$r00, $r1f

-	

 

+; Regs are stored. Prepare DMA.

 	lri		$r18, #0x0000

 	lri		$r19, #1		;(DSP_CR_IMEM | DSP_CR_TO_CPU)

 	lri		$r1a, #0x200

@@ -545,7 +554,8 @@ send_back:
 	lr		$r1e, @MEM_LO

 

 	lri		$r01, #8+8

-	

+

+; Now, why are we looping here?

 	bloop	$r01, dma_copy

 	call	do_dma

 	addi	$r1e, #0x200

@@ -553,21 +563,22 @@ send_back:
 	addi	$r1f, #0x100

 	mrr		$r18, $r1f

 	nop

+

 dma_copy:

 	nop

-	

+

+; Wait for the CPU to send us a mail.	

 	call	wait_for_dsp_mbox

 	si		@DMBH, #0x8888

 	si		@DMBL, #0xfeeb

 	si		@DIRQ, #0x0001

 	

-; wait for answer before we execute the next op	

+; wait for the CPU to recieve our response before we execute the next op	

 	call	wait_for_cpu_mbox

 	lrs		$ACL0, @CMBL

 	andi	$acl1, #0x7fff

 

-	

-	

+; Restore all regs again so we're ready to execute another op.

 	lri		$r00, #REGS_BASE+1

 	lrri	$r01, @$r00

 	lrri	$r02, @$r00

@@ -602,19 +613,18 @@ dma_copy:
 	lrri	$r1f, @$r00

 	lr		$r00, @REGS_BASE

 	

-	ret	

+	ret   ; from send_back

 	

+; I wish I knew what this 16 means.

 send_back_16:

-			

-	cw		0x8e00

+	set40

 	call	send_back	

-	cw		0x8f00

-	

+	set16

 	ret

-	

-	

-dump_memory:

 

+; This one's odd. Doesn't look like it should work since it uses acl0 but 

+; increments acm0... (acc0)	

+dump_memory:

 	lri		$r02, #0x0000

 	lri		$acl0, #0x1000

 	

@@ -622,18 +632,16 @@ dump_memory:
 	bloop	$r01, _fill_loop2			

 	

 	mrr $r03, $acl0

-	cw 0x80f0

+	nx'ld   : $AX0.H, $AX1.H, @$AR0

 	

 	mrr $r1f, $r00

 	mrr $r00, $r02

-	srri	@$r00, $r1b

+	srri @$r00, $r1b

 	mrr $r02, $r00

 	mrr $r00, $r1f

 	

-	addis	$acc0, #0x1

-	

+	addis $acc0, #0x1

+

 _fill_loop2:

 	nop

-	

-

-ret 

+	ret   ; from dump_memory