; mydriver.a

;

; Copyright (C) 2020 Paul C. Pratt, Jesus A. Alvarez

;

; You can redistribute this file and/or modify it under the terms

; of version 2 of the GNU General Public License as published by

; the Free Software Foundation. You should have received a copy

; of the license along with this file; see the file COPYING.

;

; This file is distributed in the hope that it will be useful,

; but WITHOUT ANY WARRANTY; without even the implied warranty of

; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

; license for more details.

; most of this is adapted from sample source code from Apple.

FakeSonyDriver MAIN EXPORT

BLANKS ON

STRING ASIS

kqLink EQU 0

kqType EQU 4

kioTrap EQU 6

kioCmdAddr EQU 8

kioCompletion EQU 12

kioResult EQU 16

kioNamePtr EQU 18

kioVRefNum EQU 22

kioRefNum EQU 24

kcsCode EQU 26

kcsParam EQU 28

kioBuffer EQU 32 ; Buffer to store data into

kioReqCount EQU 36 ; Requested Number of Bytes

kioActCount EQU 40 ; Actual Number of Bytes obtained

kioPosMode EQU 44 ; Positioning Mode

kioPosOffset EQU 46 ; Position Offset

killCode EQU 1 ; KillIO requested

noQueueBit EQU 9 ; trap word modifier

JIODone EQU $08FC

kCmndSonyPrime EQU $0001

kCmndSonyControl EQU $0002

kCmndSonyStatus EQU $0003

kCmndSonyClose EQU $0004

kCmndSonyOpenA EQU $0005

kCmndSonyOpenB EQU $0006

kCmndSonyOpenC EQU $0007

kCmndSonyMount EQU $0008

DHeader

DFlags DC.W $4F00 ; need lock, responds to all requests

DDelay DC.W 0 ; none

DEMask DC.W 0 ; DA event mask

DMenu DC.W 0 ; no menu

DC.W DOpen - DHeader ; offset to Open

DC.W DPrime - DHeader ; offset to Prime

DC.W DControl - DHeader ; offset to Control

DC.W DStatus - DHeader ; offset to Status

DC.W DClose - DHeader ; offset to Close

Name DC.B 5 ; length of name

DC.B '.Sony'

ALIGN 2 ; word alignment

DPrime

MOVEM.L A0-A1, -(SP) ; push ParmBlkPtr, DCtlPtr for C

SUBQ #2, A7 ; result code

MOVE.W #kCmndSonyPrime, -(A7)

BRA.B DPrimeStatusCommon

DControl

MOVEM.L A0-A1, -(SP) ; push ParmBlkPtr, DCtlPtr for C

SUBQ #2, A7 ; result code

MOVE.W #kCmndSonyControl, -(A7)

LEA TailData, A0

MOVE.L (A0)+, -(A7)

MOVEA.L (A0), A0

MOVE.L A7, (A0)

ADDA.W #6, A7

MOVE.W (A7)+, D0 ; save result code

MOVEM.L (SP)+, A0-A1 ; restore ParmBlkPtr, DCtlPtr

CMPI.W #killCode,kcsCode(A0) ; test for KillIO call (special case)

BNE.B IOReturn

RTS ; KillIO must always return via RTS

DStatus

MOVEM.L A0-A1, -(SP) ; push ParmBlkPtr, DCtlPtr for C

SUBQ #2, A7 ; result code

MOVE.W #kCmndSonyStatus, -(A7)

DPrimeStatusCommon

LEA TailData, A0

MOVE.L (A0)+, -(A7)

MOVEA.L (A0), A0

MOVE.L A7, (A0)

ADDA.W #6, A7

MOVE.W (A7)+, D0 ; save result code

MOVEM.L (SP)+, A0-A1 ; restore ParmBlkPtr, DCtlPtr

IOReturn

MOVE.W kioTrap(A0),D1

BTST #noQueueBit,D1 ; immediate calls are not queued, and must RTS

BEQ.B @Queued ; branch if queued

@NotQueued

TST.W D0 ; test asynchronous return result

BLE.B @ImmedRTS ; result must be <= 0

CLR.W D0 ; "in progress" result (> 0) not passed back

@ImmedRTS

MOVE.W D0,kioResult(A0) ; for immediate calls you must explicitly

; place the result in the ioResult field

RTS

@Queued

TST.W D0 ; test asynchronous return result

BLE.B @MyIODone ; I/O is complete if result <= 0

CLR.W D0 ; "in progress" result (> 0) not passed back

RTS

@MyIODone

MOVE.L JIODone,-(SP) ; push IODone jump vector onto stack

RTS

DClose

MOVEM.L A0-A1, -(SP) ; push ParmBlkPtr, DCtlPtr for C

SUBQ #2, A7 ; result code

MOVE.W #kCmndSonyClose, -(A7)

LEA TailData, A0

MOVE.L (A0)+, -(A7)

MOVEA.L (A0), A0

MOVE.L A7, (A0)

ADDA.W #6, A7

MOVE.W (A7)+, D0 ; save result code

MOVEM.L (SP)+, A0-A1 ; restore ParmBlkPtr, DCtlPtr

RTS

DUpdate

MOVEM.L D0-D2/A0-A1,-(SP)

MOVE.L 20(A7),D0 ; data = what was on top of stack before 5 registers pushed

SUBQ #4, A7 ; room for eventMsg

MOVE.L D0,-(A7) ; data

SUBQ #2, A7 ; room for result code

MOVE.W #kCmndSonyMount, -(A7)

LEA TailData, A0

MOVE.L (A0)+, -(A7)

MOVEA.L (A0), A0

MOVE.L A7, (A0)

ADDA.W #6, A7

MOVE.W (A7)+, D1 ; result code

ADDQ #4, A7 ; skip over data

MOVE.L (A7)+, D0 ; eventMsg

TST.W D1 ; result code

BNE.S @1

MOVEA.W #$0007,A0

DC.W $A02F ; _PostEvent

@1

MOVEM.L (SP)+,D0-D2/A0-A1

ADDA.W #4,A7 ; remove arguments from stack

RTE

MyAddDrive64k

; This is only needed for the 64k ROM.

DrvQHdr EQU 776

RomBase EQU $00400000

Move.L D0,6(A0)

Lea.L (DrvQHdr),A1

Jmp (RomBase + 2848)

VBLTaskFreq EQU $0E19

; about once a minute, often enough that

; a problem with VBLTaskProc noticable.

VBLTaskProc

MOVE.W VBLTaskFreq, $000A(A0)

; fall through to return

NullTaskProc

RTS

DOpen

MOVEM.L D3-D7/A3-A4,-(A7)

MOVEM.L A0-A1, -(SP) ; push ParmBlkPtr, DCtlPtr for C

SUBQ #6, A7 ; room for result code, L

MOVE.W #kCmndSonyOpenA, -(A7)

LEA TailData, A0

MOVE.L (A0)+, -(A7)

MOVEA.L (A0), A0

MOVE.L A7, (A0)

ADDA.W #6, A7

MOVE.W (A7)+, D0 ; result code

MOVE.L (A7)+, D7 ; L

CMPI.W #$FFCF,D0

BNE.S @1

; driver already open, change to no error and leave

CLR.W D0

BRA @2

@1

TST.W D0

BNE @2

MOVE.L D7,D0

DC.W $A71E ; _NewPtr ,Sys,Clear

MOVEA.L A0,A4

MOVE.L A4,D0

BEQ @6

SUBA #16, A7 ; room for various results

MOVE.L A4, -(A7)

MOVE.L D7, -(A7)

SUBQ #2, A7 ; room for result code

MOVE.W #kCmndSonyOpenB, -(A7)

LEA TailData, A0

MOVE.L (A0)+, -(A7)

MOVEA.L (A0), A0

MOVE.L A7, (A0)

ADDA.W #6, A7

MOVE.W (A7)+, D0 ; result code

ADDA.W #8, A7

MOVE.L (A7)+, D7 ; dvl

MOVEQ #$00, D3

MOVE.W (A7)+, D3 ; step

MOVE.W (A7)+, D4 ; n

MOVE.W (A7)+, D6 ; i

MOVE.W (A7)+, D5 ; driver

MOVEA.L (A7)+, A3 ; NullTask

TST.W D0

BNE.S @2

; Patch from Jesus A. Alvarez:

; The program Winter Games by Epyx manipulates

; the VBL queue directly, and will break if the

; queue was empty. Add a VBL task to prevent this

; (like the real disk driver does).

; MOVE.L #14, D0

; DC.W $A71E ; _NewPtr ,Sys,Clear

LEA 48(A4), A0

LEA VBLTaskProc,A1

MOVE.W #1,$0004(A0) ; task type

MOVE.L A1,$0006(A0) ; task procedure

MOVE.W VBLTaskFreq,$000A(A0)

DC.W $A033 ; _VInstall

MOVE.L A3,D0

BEQ.S @3

; There is apparently a bug in the time manager

; in System 6.0.8, which will cause a crash

; if there are no installed time

; tasks. So create a time task, since

; real disk driver does.

LEA NullTaskProc,A0 ; id: 102

MOVE.L A0,$0006(A3)

MOVEA.L A3,A0

DC.W $A058 ; _InsTime

BRA.S @4

@3

LEA MyAddDrive64k,A0 ; id: 106

MOVE.W #$A04E,D0

DC.W $A047 ; _SetTrapAddress

BRA.S @4

@5

MOVEA.L D7,A0

MOVE.W D6,D0 ; drive number in high word

SWAP D0

MOVE.W D5,D0 ; driver in low word

DC.W $A04E ; _AddDrive

ADD.L D3,D7

ADDQ.W #$1,D6

@4

DBF D4, @5

PEA DUpdate

SUBQ #2, A7 ; room for result code

MOVE.W #kCmndSonyOpenC, -(A7)

LEA TailData, A0

MOVE.L (A0)+, -(A7)

MOVEA.L (A0), A0

MOVE.L A7, (A0)

ADDA.W #6, A7

MOVE.W (A7)+, D0 ; result code

ADDA.W #4, A7

@2

; result code should be in D0 when reach here

MOVEM.L (A7)+, A0-A1 ; restore ParmBlkPtr, DCtlPtr

MOVEM.L (A7)+, D3-D7/A3-A4

RTS ; open is always immediate, must return via RTS

@6

; _NewPtr failed

MOVE.W #-1, D0

BRA.S @2

TailData

ENDMAIN

END