sys7.1-doc-wip/OS/SCSIMgr/SCSIMgrHW.a
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;
; File: SCSIMgrHW.a
;
; Copyright: © 1989-1993 by Apple Computer, Inc. All rights reserved.
;
; Change History (most recent first):
;
; <SM10> 2/5/93 CSS Rollin from Horror: clear flag indicating drive is now spun down.
; <SM9> 11/3/92 SWC Changed SCSIEqu.a->SCSI.a.
; <SM8> 9/9/92 CSS Changed three bra.w's to bra.l's when modular makes
; caused the files to get to far apart.
; <SM7> 6/20/92 PN Roll in patchIIciROM.a. New and improved bus errorhandler
; <SM6> 6/2/92 kc Revert to <SM4>
; <SM5> 6/1/92 CS Roll more cyclone stuff in.
; <SM4> 5/17/92 kc Include PowerPrivEqu.a. The powerCntl equ was moved inside the
; pmCommandRec record.
; <SM3> 5/4/92 FM Undo last change and let Kurt deal with it :^)
; <SM2> 5/4/92 FM Roll in changes from PatchIICiRom.a file that were "lost" in the
; review process… Making the SCSIBusErrHandler a little more
; robust.
; <13> 12/27/91 RB Rolled in Terror changes. Cleaned up a bit.
; <12> 10/2/91 JSM Dont use any onXXMac conditionals at all, dont use forROM,
; isUniversal, or hasPwrControls since they are always true for
; this file, dont check for Cpu ≥ 020 since it always is.
; <11> 9/16/91 JSM Cleanup header.
; <10> 9/21/90 BG Removed <8>, <9>. 040s are behaving more reliably now.
; <9> 7/19/90 BG Found another place or two where EclipseNOPs were needed.
; <8> 6/22/90 CCH Added a NOP for flaky 68040's.
; <7> 5/16/90 MSH Added hasPowerControls to hcmac conditional.
; <6> 2/20/90 BG Added (simplistic) 040 bus error handling. Updated *Transfer* to
; decide which MaxBusErr value to use (000/020/030 vs. 040).
; <5> 1/18/90 JWK Needed for Zone5 - Fixes to old SCSI Mgr DMA routines for
; SCSIStat support and variable blind timeouts.
; <4> 1/14/90 JWK Needed for F19 - Added calls to LockMemory and UnlockMemory for
; VM support.
; <3> 1/11/90 CCH Added include of “HardwarePrivateEqu.a”.
; <2> 1/8/90 JK Needed for F19: Fixed CD-ROM bug in slow read routines - better
; loss of phase error checking.
; <1.7> 12/10/89 jwk NEEDED FOR F19 - Optimized DMA code
; <1.6> 11/2/89 MSH Rolled in updated sleeptask from hcmac reality sources.
; <1.5> 9/11/89 jwk NEEDED FOR F19 - Cleaned up DMA code, added support for SE and
; Plus
; <1.4> 7/17/89 jwk NEEDED FOR AURORA - Changed to use "padForOverPatch" conditional
; <1.3> 7/15/89 jwk NEEDED FOR AURORA - Code review changes, F19 routines
; <1.2> 6/29/89 jwk NEEDED FOR AURORA - Fixed Tape Drive and Slow Write timing bugs
; <1.1> 6/19/89 SWC Replaced bit constants for equated versions for OSS interrupt
; register tests.
; <1.0> 6/13/89 jwk Reorganizing SCSI sources to be Universal-ROM friendly
;
; Old comments are saved for historical purposes in the SCSIMgrOld.a file. <v1.3>
;
;-----------------------------------------------------------
BLANKS ON
STRING ASIS
PRINT OFF
IF (&TYPE('dbSymbols') = 'UNDEFINED') THEN
dbSymbols EQU 0 ; for debugging purposes <v1.5>
ENDIF
IF (&TYPE('phaseLogging') = 'UNDEFINED') THEN
phaseLogging EQU 0
ENDIF
LOAD 'StandardEqu.d'
INCLUDE 'HardwarePrivateEqu.a'
INCLUDE 'UniversalEqu.a' ; <13> rb
INCLUDE 'PowerPrivEqu.a'
INCLUDE 'SCSI.a'
INCLUDE 'SCSIPriv.a'
INCLUDE 'SCSIEqu96.a' ; <13> rb
PRINT ON
SCSIHW PROC EXPORT
EXPORT Arb, Sel, Delay22, SCSIIntHnd
EXPORT Transfer, SlowComp, FastComp
EXPORT SlowRead, SlowWrite, FastRead, FastWrite
EXPORT VFastReadOSS, VFastRead, VFastWriteOSS, VFastWrite
EXPORT PFastReadOSS, PFastRead, PFastWriteOSS, PFastWrite
EXPORT FastReadOSS, FastWriteOSS ;<v1.3>
EXPORT BusErrHandler ;<v1.5>
EXPORT ClearIRQ
EXPORT DisEnable
IMPORT ClearSCSIInt, EnableSCSIInts, DisableSCSIInts
WITH scsiPB,scsiPrivPB, scsiGlobalRecord, dcInstr, PmgrRec
EXPORT SleepTask, DoSpinDown
;-------------------------------------------------------------------
;
; DoSpinDown - Turn hard drive power off. <v1.1><v1.2>
;
; It is assumed that the drive power is on - the power is cut unconditionally.
;
with pmCommandRec
DoSpinDown
link a6,#-14 ; storage for Power Mgr param blk <v1.1>
@cutPower
lea.l -14(a6),a0 ; point to the parameter block <v1.1>
move.w #powerCntl,pmCommand(a0) ; power off the SCSI +5V and +12V <v1.1>
move.w #1,pmLength(a0) ; one byte of data in buffer <v1.1>
move.w #hdOff*256,-2(a6) ; hdOff command <v1.1>
pea.l -2(a6) ; address of send buffer <v1.1>
move.l (sp)+,pmSBuffer(a0) ; save the send buffer pointer <v1.1>
move.l zeroReg,pmRBuffer(a0) ; no data to be received <v1.1>
_PmgrOp ; send it off to the Power Mgr <v1.1>
tst.w d0 ; was there an error ? <v1.1>
bne.s @exit ; if there was, don't freeze the timer <v1.8>
@success
MOVE.L PmgrBase,A0 ; get pointer to pmgr locals <v2.1>
clr.l LastHd(A0) ; stop calling - disk is spun down <v1.8>
bclr.b #HDPowerOn,PmgrFlags(a0) ; clear flag indicating drive is now spun down <t11> djw <SM10> CSS
@exit
unlk a6 ; release local storage <v1.1>
rts ; <v1.1>
endwith
;-------------------------------------------------------------------
;
; SleepTask - Turn hard drive power off, if necessary <v1.2>
;
; If the Sleep timer goes off, or the user decides to go immediately to sleep, this task
; is called. If no SCSI I/O is in progress, the power is turned off to the drive. <v1.2>
;
SleepTask
MOVE.L A1,-(SP) ; save A1
cmpi.w #SleepDemand,d0 ; is it a sleep demand ? <v1.4>
beq.s @spin ; if so, do it <v1.4>
cmpi.w #SleepNow,d0 ; is it a sleep now ? <v1.4><v1.6>
beq.s @spin ; if so, do it <v1.4>
cmpi.w #SleepRequest,d0 ; is it a sleep request ? <v1.4>
bne.s @exit ; if not, ignore it <v1.4>
move.l SCSIGlobals,a1 ; point to SCSI Mgr globals <v1.4>
tst.l scsiQHead(a1) ; is the new SCSI Mgr busy ? <v1.2>
bne.s @err ; we're busy, so we won't sleep <v1.4><v1.3>
@spin
MOVE.L PmgrBase,A1 ; use pointer to spin down routine <v1.5>
MOVE.L HDvector(A1),A1
JSR (A1)
@exit
clr.l d0 ; <v1.3>
@err
move.l (sp)+,a1 ; restore a1 <v1.2><v1.3>
rts ; we're out of here <v1.4>
;
; ClearIRQ
;
; Function: Clears the SCSI IRQ bit and the VIA interrupt flag, if necessary.
;
ClearIRQ:
move.b sRESET(a3),d1 ; clear the IRQ interrupt bit
bra.l ClearSCSIInt ; <SM8> call InterruptHandlers.a to clear SCSI intr latch (if any) <v1.3>
;
; DisEnable
;
; Called by: SCSIDT, ArbSel, SCSIIntHnd, MsgIn
;
; Calls: _PrimeTime (on the Mac Plus)
;
; On entry: d0 - If zero, disable SCSI interrupts, else enable SCSI interrupts
;
; Function: Enable/disable the CPU's SCSI interrupt.
;
DisEnable:
tst.l d0 ; disable or enable ?
beq.s @disable ; if zero, disable interrupts
@enable
bra.l EnableSCSIInts ; <SM8> use routine in InterruptHandlers.a <v1.3>
@disable
bra.l DisableSCSIInts ; <SM8> use routine in InterruptHandlers.a <v1.3>
;
; BusErrHandler -- Hardware-handshaking bus error handler
;
aeXFrameType EQU $07 ; Access Error Exception Stack Frame type value <6>
aeXFrameSize EQU 30*2 ; size (words) of 040 AE Exception Frame <6>
shortBEXFrameType EQU $0A ; Short bus cycle fault stack frame (020/030) <6>
BusErrHandler:
move.l d0,-(sp) ; save d0 <PN>
moveq.l #$ffffff9c,d0 ; mask = $ffffff9c <Start> <PN>
and.l 4+$10(sp),d0 ; clear variable bits of the fault address <PN>
cmp.l SCSIHsk,d0 ; was it a SCSI chip access ? <PN>
beq.s @start ; if so, start processing the bus error <PN>
movem.l d1/a4,-(sp) ; save what we will trash <PN>
move.l SCSIGlobals,a4 ; load our globals reference <PN>
move.l SCSI2Base,d1 ; is the external SCSI chip base address valid? <PN>
beq.s @NoSCSIBus2 ; -> no, cleanup and bail <PN>
cmp.l hhsk5380_2(a4),d0 ; was it an external SCSI chip access ? <PN>
beq.s @Is2ndSCSI ; if so, start processing the bus error <PN>
@NoSCSIBus2 ; <PN>
movem.l (sp)+,d1/a4 ; restore d1/a4 <PN>
move.l (sp)+,d0 ; restore d0
move.l OldBusErrVct(a6),-(sp) ; put old bus error handler addr on stack <end>
rts ; jump to old handler, assuming it'll RTE <PN>
@Is2ndSCSI ; <PN>
movem.l (sp)+,d1/a4 ; restore d1/a4 <PN>
@start
subq.w #1,BusErrCount(a6) ; retry until we get tired
beq.s CleanUp
move.w TimeDBRA,d0 ; DBRA's per millisecond <v1.3>
lsr.w #4,d0 ; 1ms/16 = approximately 62us (was 50us) <v1.3>
@ErrWait dbra d0,@ErrWait ; recovery time (was 50us) <C865/PB208> <v1.3>
move.l (sp)+,d0 ; restore d0 <v2.0>
rte ; haven't reached max, so restart
Cleanup
addq.l #4,sp ; throw away copy of d0 on stack <29>
move.w (sp),d0 ; get sr from stack
bfextu 6(sp){0:4},d1 ; get format code from stack
cmp.b #aeXFrameType,d1 ; check for 040 Access Error Exception Frame <6>
beq.s Drop040XFrame ; dispose of 040 AE except. frame <6>
cmp.b #shortBEXFrameType,d1 ; short 020/030 exception frame?
bne.s Drop46w ; no, so use larger frame
adda.w #16*2,sp ; dispose of the 16-word frame
bra.s DummyFrame ; and finish up
Drop040XFrame ; 040 Bus Error frame-cleaning done here <6>
add.w #aeXFrameSize,sp ; remove 040 Access Error Exception Frame <6>
bra.s DummyFrame ; and create dummy return frame <6>
Drop46w
add.w #46*2,sp ; size of exception frame
DummyFrame
;
; Fake a format code 0 exception frame (4 words) to finish cleaning up
;
move.w zeroReg,-(sp) ; format code 0
pea FinishErr ; PC value
move.w d0,-(sp) ; sr value
rte ; 'return' from the fake exception
FinishErr
moveq.l #scBusTOErr, d0 ; assume slow peripheral <13> rb
TestFor SCSI96_1Exists ; use macro to check if we have <13> rb
beq.s @noSCSI96 ; a SCSI96 chip. Bra. if not <13> rb
;In c96 DMA mode, if the phase changes while transfer count > 0
; during transfer info then c96 generates a bus service interrupt.
rts ; But return SCSI Bus TimeOut for now <13> rb
@noSCSI96
btst.b #bPM, (a1) ; phase change? <13> rb
bne.s @ErrorDone ; phase matches: slow peripheral <13> rb
moveq.l #scPhaseErr, d0 ; return phase change error <13> rb
@ErrorDone
rts
;
; Arb
;
; Called by: SCSIDT
;
; Calls: Delay22.
;
; On entry: a3 - ptr to SCSI read base address
; a4 - ptr to SCSI Mgr globals
;
; On exit: d0 - result code
;
; Function: Arbitrates for the SCSI bus.
;
Arb:
movem.l a0-a3/d1-d2,-(sp) ; save registers
move.w #scsiArbitrated,scsiResult(a5) ; we're arbitrating
moveq.l #noErr,d0 ; assume success
btst.b #sOSSExists,G_Reserved0+3(a4) ; see if we really have an OSS
beq.s @notGDUOSS ; if not, skip it
btst.b #sSCSIDMAExists,G_Reserved0+3(a4) ; see if we have a SCSI DMA chip
beq.s @notGDUOSS ; not the correct combination
move.l #$FFFFFFFF,sDTIME(a3) ; set timer to an outlandish value <v1.3><v1.5>
move.l G_Reserved2(a4),sDCTRL(a3) ; enable auto-arbitration <v1.2>
move.b #iARB,sMR+WrOffs(a3) ; attempt arbitration
move.w TimeDBRA,d2 ; DBRA's per millisecond <v1.3>
lsr.w #6,d2 ; 1ms/64 = 15us <v1.3>
@delay
dbra.w d2,@delay ; delay at least 15us <v1.3>
move.l sDCTRL(a3),d1 ; get an image of the DMA control register
btst.l #bWONARB,d1 ; did we win ?
beq.s @busyGDU ; we didn't win
move.b sRESET(a3),d1 ; clear the interrupt <v1.3>
move.l #iINTREN,sDCTRL(a3) ; enable chip interrupts <v1.3>
bra.s @exit ; we won <v1.3>
@busyGDU
move.l #iINTREN,sDCTRL(a3) ; turn off auto-arbitration <v1.3>
bra.s @busy ; continue <v1.3>
@notGDUOSS
move.b G_ID(a4),sODR+WrOffs(a3) ; put CPU's ID out on the bus
move.b #iARB,sMR+WrOffs(a3) ; attempt arbitration
btst.b #bAIP,sICR(a3) ; check for AIP (Arbitration In Progress) bit
beq.s @busy ; the bus is busy
@delay22:
movea.l jvDelay22(a4),a0 ; delay at least 2.2us
jsr (a0) ; go to the routine
@checkWin:
btst.b #bLA,sICR(a3) ; did we lose arbitration ?
bne.s @busy ; if we lost, get out
move.b G_ID(a4),d2 ; CPU's SCSI ID <v1.3>
move.b sCDR(a3),d1 ; check ID's on the bus
eor.b d2,d1 ; take out our ID <v1.3>
cmp.b d2,d1 ; is there a higher ID on the bus ?
bhi.s @busy ; if so, we lost, so get out
btst.b #bLA,sICR(a3) ; check again - did we lose arbitration ?
beq.s @exit ; we won - d0 is set correctly
@busy:
bset.b #waitingForIRQ,state1(a4) ; we're waiting for a Loss of BSY interrupt <v1.5>
move.b zeroReg,sMR+WrOffs(a3) ; turn off arbitration
move.b #iMBSY,sMR+WrOffs(a3) ; set up for "Loss of BSY" interrupt
moveq.l #scArbNBErr,d0 ; we didn't win
@exit:
movem.l (sp)+,a0-a3/d1-d2 ; restore registers (d0 is not restored)
tst.l d0 ; set condition codes
rts
;
; Sel
;
; Called by: SCSIDT
;
; Calls: Delay22.
;
; On entry: a3 - ptr to SCSI read base address
; a4 - ptr to SCSI Mgr globals
; a5 - ptr to SCSI request parameter block
;
; On exit: d0 - result code
;
; Function: Selects a device.
;
Sel:
movem.l scsiRegs,-(sp) ; save registers
move.w #scsiSelection,scsiResult(a5) ; we're attempting to select
move.b #iSEL+iBSY,sICR+WrOffs(a3) ; assert SEL as well as BSY since we won
move.b zeroReg,sMR+WrOffs(a3) ; turn off arbitration
movea.l jvDelay22(a4),a0 ; delay at least 1.2us (800+400ns) <v1.3>
jsr (a0) ; go to the routine
@select: ; start selection
move.b zeroReg,sTCR+WrOffs(a3) ; clear *I/O bit to become initiator
moveq.l #1,d1 ; build the select mask...
move.b scsiReqID(a5),d2 ; Target ID
lsl.b d2,d1 ; shift the bit to the appropriate spot
or.b G_ID(a4),d1 ; merge CPU ID with Target ID
move.b d1,sODR+WrOffs(a3) ; set select mask (ready to be output onto bus)
move.b #iBSY+iSEL+iDB+iATN,sICR+WrOffs(a3) ; assert *SEL,*DB, and *ATN
move.b zeroReg,sSER+WrOffs(a3) ; disable reselection interrupts
move.l zeroReg,d0 ; disable all SCSI interrupts
move.l jvDisEnable(a4),a0 ; addr of intr enable/disable routine
jsr (a0) ; disable SCSI interrupts
move.b #iSEL+iDB+iATN,sICR+WrOffs(a3) ; *SEL, *DB, and *ATN - no *BSY
movea.l jvDelay22(a4),a0 ; bus settle delay (400ns)
jsr (a0) ; go to the routine
@timeout
move.w scsiSelTO(a5),d2 ; selection timeout in milliseconds
mulu.w TimeSCSIDB,d2 ; get number of DBRA's
move.l d2,d0 ; set up d0 as high word
swap d0
@wfbsy
btst.b #bBSY,sCSR(a3) ; test for *BSY
dbne.w d2,@wfbsy ; loop until *BSY or timeout
dbne.w d0,@wfbsy
bne.s @noerror ; *BSY is asserted
@nobsy
move.b #iSEL,sICR+WrOffs(a3) ; de-assert data bus
move.w TimeSCSIDB,d2 ; delay 200us
lsr.w #2,d2 ; 1ms/4 = 250us (greater than 200us)
@delay
dbra.w d2,@delay ; wait 250us
btst.b #bBSY,sCSR(a3) ; *BSY asserted ?
bne.s @noerror ; if asserted, we're done
@error
move.w #scsiSelectTOErr,d0 ; selection timed out <v1.3>
move.b zeroReg,sICR+WrOffs(a3) ; release the lines
bra.s @exit ; done
@noerror
movea.l jvDelay22(a4),a0 ; bus settle delay (400ns)
jsr (a0) ; go to the routine
move.b #iATN,sICR+WrOffs(a3) ; assert *ATN only
moveq.l #noErr,d0 ; indicate success
@exit:
movem.l (sp)+,scsiRegs ; restore registers (d0 is not restored)
tst.l d0 ; set condition codes
rts
;
; Delay22();
;
; Called by: Arb, Sel
;
; Calls: None.
;
; Function: Provides a delay of at least 2.2us, using three VIA accesses <v1.3>
; as a time constant. <v1.3>
;
Delay22:
movea.l VIA,a0 ; point to the VIA <v1.3>
tst.b vIFR(a0) ; access the VIA <v1.3>
tst.b vIFR(a0)
tst.b vIFR(a0)
rts
;
; SCSIIntHnd
;
; Called by: Macintosh Interrupt Dispatcher
;
; Calls: Command, Status, Data, MsgIn, MsgOut
;
; Function:
; This is the SCSI interrupt handler. (On the Mac Plus, a second timer is used to
; monitor the SCSI chip's interrupt line.)
;
SCSIIntHnd:
IF dbSymbols THEN
link a6,#0 ; no globals, no locals
nop
ENDIF
movem.l intrRegs,-(sp) ; save registers
movea.l SCSIGlobals,a4 ; get pointer to SCSI Manager globals <v1.7>
SCSIIntHndCommon
movea.l activeReq(a4),a5 ; point to the active request, if any <v1.3>
moveq.l #0,zeroReg ; clear out the zero register
move.l zeroReg,d0 ; disable all SCSI interrupts
move.l jvDisEnable(a4),a0 ; addr of intr enable/disable routine
jsr (a0) ; disable SCSI interrupts
move.l base5380(a4),a3 ; SCSI read base address
move.w sr,-(sp) ; save current status register contents
ori.w #HiIntMask,sr ; no interrupts during Reselection handshake
move.b sBSR(a3),d0 ; fetch Bus and Status Register
btst.l #bIREQ,d0 ; is the IRQ bit set ?
beq.w @Spurious ; if not, check for spurious interrupt
lsl.w #8,d0 ; put BSR in upper byte
move.b sCSR(a3),d0 ; put Current SCSI Bus Status in lower byte
move.w d0,d1 ; get a copy of BSR and CSR registers
andi.w #mReselect,d1 ; clear don't care bits
cmpi.w #iReselect,d1 ; is it a Reselection interrupt ?
bne.s @chkEOP ; if not, check for an End Of Process interrupt
@Reselect
;
; Since we're not a system with Parity implemented, we can't check for parity
; on Reselection. It's not worth the trouble to keep track of the ID's that implement
; Parity.
;
; btst.l #bDBP,d0 ; is /DBP asserted ?
; beq.w @Spurious ; if not, bad parity, don't respond
move.b sCDR(a3),d1 ; get ID of reselecting device
beq.w @Spurious ; no ID bits set
move.b G_ID(a4),d0 ; get our ID bit
eor.b d0,d1 ; remove our ID bit
beq.w @Spurious ; only our ID bit was set, invalid reselection
move.b zeroReg,sSER+WrOffs(a3) ; disable reselection interrupts
move.b sICR(a3),d0 ; assert *BSY
ori.b #iBSY,d0
move.b d0,sICR+WrOffs(a3)
moveq.l #scResel,d0 ; send a reselect message to dTask (ID mask in d1.b)
bra.s @ClearIRQ ; clear interrupt and leave
@chkEOP
move.w d0,d1 ; get a copy of BSR and CSR registers
andi.w #mEOP,d1 ; clear don't care bits
cmpi.w #iEOP,d1 ; is it an End Of Process interrupt ?
bne.s @PhaseMm ; if not, check for Phase Mismatch
@EOPIntr
move.b zeroReg,sMR(a3) ; clear EOP interrupt (and turn off pDMA)
move.b zeroReg,sICR(a3) ; deassert the data bus (for writes) <v1.3>
moveq.l #scEOP,d0 ; send an EOP message to dTask
bra.s @ClearIRQ ; clear interrupt and leave
@PhaseMm
move.w d0,d1 ; get a copy of BSR and CSR registers
andi.w #mPhaseMm,d1 ; clear don't care bits
cmpi.w #iPhaseMm,d1 ; is it a Phase Mismatch interrupt ?
bne.s @LossBsy ; if not, check for Loss of BSY <v1.3>
moveq.l #scPhaseMm,d0 ; send a Phase Mismatch message to dTask
bra.s @ClearIRQ ; clear interrupt and leave
@LossBsy
move.w d0,d1 ; get a copy of BSR and CSR registers
andi.w #mLossBsy,d1 ; clear don't care bits
cmpi.w #iLossBsy,d1 ; is it a Loss of BSY interrupt ?
bne.s @BusReset ; if not, check for SCSI Bus Reset
moveq.l #scLossBsy,d0 ; send a Loss of BSY message to dTask
bra.s @ClearIRQ ; clear interrupt and leave
@BusReset
move.w d0,d1 ; get a copy of BSR and CSR registers
andi.w #mBusReset,d1 ; clear don't care bits
cmpi.w #iBusReset,d1 ; is it a SCSI Bus Reset interrupt ?
bne.s @Parity ; if not, check for a Parity interrupt
; moveq.l #scBusReset,d0 ; send a Bus Reset message to dTask <v1.3>
bra.s @Spurious ; clear IRQ, leave as if nothing happened <v1.3>
@Parity
move.w d0,d1 ; get a copy of BSR and CSR registers
andi.w #mParity,d1 ; clear don't care bits
cmpi.w #iParity,d1 ; is it a Parity Error interrupt ?
bne.s @Spurious ; if not, spurious interrupt <v1.5>
moveq.l #scParity,d0 ; send a Parity error message to dTask
; fall through to clear interrupt request and leave <v1.3>
@ClearIRQ
movea.l jvMessage(a4),a0 ; addr of messaging routine <v1.3>
jsr (a0) ; send the message to the deferred task <v1.3>
movea.l jvClearIRQ(a4),a0 ; addr of ClearIRQ routine
jsr (a0) ; clear the SCSI interrupt (and VIA, if necessary)
move.w (sp)+,sr ; restore the sr
IF phaseLogging THEN
nop ; good place to jump to phase-logging routine
ENDIF
bra.s @inthndRTS ; we're done
@Spurious
move.w (sp)+,sr ; restore the sr
btst.b #sSCSIDMAExists,G_Reserved0+3(a4) ; do we have a SCSI DMA chip ? <v1.3>
beq.s @DMAdone ; if not, skip <v1.3>
move.l sDCTRL(a3),d0 ; get a snapshot of DMA control register <v1.3>
btst.l #bTIMEP,d0 ; did the watchdog timer go off ? <v1.3>
beq.s @DMAdone ; if not, continue <v1.3>
if dbSymbols then
_Debugger
endif
move.w #scsiBusTOErr,d0 ; report that the watchdog timer expired
movea.l jvLogError(a4),a0 ; note the SCSI error in the PB
jsr (a0) ; send it
moveq.l #-1,d0 ; clear the timer interrupt <end>
move.l d0,sDTIME(a3) ; hit the watchdog timer to clear the intr <v1.3>
@DMAdone
movea.l jvClearIRQ(a4),a0 ; addr of ClearIRQ routine
jsr (a0) ; clear the VIA interrupt, if necessary
moveq.l #1,d0 ; flag to enable interrupts
movea.l jvDisEnable(a4),a0 ; addr of interrupt enable/disable routine
jsr (a0) ; turn interrupts back on
@inthndRTS
movem.l (sp)+,intrRegs ; restore registers
IF dbSymbols THEN
unlk a6
rts ; finished
dc.b 'INTHND ' ; MacsBug label
ELSE
rts
ENDIF
;
; Transfer -
;
; Called by: Data
;
; Calls: The primitive data transfer routines
;
; Registers: d0 <-- error, if any
; d1 <-- bytes transferred
; d2 --> number of bytes to transfer
; d3 --> bDMAR (6) <v1.3>
; d4 --> type of transfer to perform (offset into "dataTable")
;
; a2 --> ptr to data buffer
;
; Function: Sets up and dispatches to the simple data-transfer routines
;
; All primitive data transfer routines assume:
;
; d0 - <-- error (if any)
; d1 - <-- bytes transferred
; d2 - --> number of bytes to transfer
; d3 - scratch - saved
; d4 - --> type of transfer to perform
; d5 - scratch - saved
; d6 - scratch - saved
;
; a0 - scratch - saved
; a1 - saved - sBSR(a3)
; a2 - ptr to data buffer - saved
; a3 - SCSI read base address
; a4 - ptr to SCSI Mgr globals
; a5 - scratch - saved
;
Transfer:
link a6,#LocalSize ; allocate local storage
moveq #MaxBusErr,d0 ; upper limit for 680x0's <v1.3><v1.5><6>
cmp.b #cpu68040,CpuFlag ; check if we're on an 040 <6>
bne.s @storeValue ; NO ... leave BusErrCount alone <6>
moveq #Max040BusErrs,d0 ; YES ... use 040 MaxBusErr value <6>
@storeValue ; <6>
move.w d0,BusErrCount(a6) ; store upper limit for allowable bus errors <6>
moveq.l #noErr,d0 ; assume no error
move.l d2,d1 ; make a copy of the count - is it zero ?
beq.s @exit ; if so, get out
movem.l a1-a5/d2-d6,-(sp) ; save registers
lea.l sBSR(a3),a1 ; save later indexing
moveq.l #bDMAR,d3 ; bit DRQ test on sBSR(a3) (for speed)
move.l BusErrVct,OldBusErrVct(a6) ; keep old vector
move.l jvBusErr(a4),BusErrVct
lea.l dataTable(a4),a0 ; point to data transfer table in globals
movea.l 0(a0,d4.l),a0 ; get the routine address
jsr (a0) ; go to the appropriate routine
@done
move.l OldBusErrVct(a6),BusErrVct ; restore previous Bus Error vector
movem.l (sp)+,a1-a5/d2-d6 ; restore these guys
tst.w d0 ; set the condition codes
@exit
unlk a6 ; release local storage
rts
;
; All primitive data transfer routines use this convention:
;
; d0 - type of transfer to perform / error (if any)
; d1 - number of bytes to transfer / bytes transferred
; d2 - number of bytes to transfer
; d3 - bDMAR (6)
; d4 - scratch - saved
; d5 - scratch - saved
; d6 - scratch - saved
;
; a0 - special I/O address (pDMA or hhsk base, plus input/output register offset)
; a1 - sBSR(a3)
; a2 - ptr to data buffer
; a3 - SCSI read base address
; a4 - ptr to SCSI Mgr globals
; a5 - scratch - saved
;
;
; SlowRead
;
; Called by: Transfer
;
SlowRead:
@RdSetup
move.l pdma5380(a4),a0 ; use the global <C406/12Nov86>
adda.l #sIDR,a0 ; input data offset <C406/12Nov86>
subq.l #1,d2 ; decr. for DBRA <C478/10Dec86>
move.l d2,d5 ; make a copy of the byte count
swap d5 ; and get hiword in d5
@wait
btst.b d3,(a1) ; DRQ ? <v1.3>
bne.s @SnRd ; if so, start the transfer <v1.3>
btst.b #bREQ,sCSR(a3) ; look for REQ <v1.3>
beq.s @wait ; can't check phase until REQ is asserted <v1.3>
btst.b #bPM,(a1) ; we have REQ, do we have a phase match ? <v1.3>
beq.s @RdPhaseErr ; if not, bail out with an error <v1.3>
;
; This is the loop for polled reads. Byte count is in d2,d5
;
@SnRd
btst.b d3,(a1) ; DRQ? <C478/10Dec86>
beq.s @SnRdChk ; (9)
move.b (a0),(a2)+ ; read bytes into user space (13)
dbra d2,@SnRd ; decrement count
dbra d5,@SnRd ; high word of count
bra.s @RdDone ; we're done
@SnRdChk
bsr.w NewPhaseCheck ; check more carefully for phase match <1>
bne.s @SnRd ; continue if it is
@RdPhaseErr
moveq.l #scPhaseErr,d0 ; return error
bra.s @exit
@RdDone
btst.b #bACK,sBSR(a3) ; check for ACK <3.0>
beq.s @exit ; if no ACK, we're done <3.0>
@ACK
@wfnREQ
btst.b #bREQ,sCSR(a3) ; test for *REQ <3.0>
beq.s @exit ; if it's gone, we're done <3.0>
btst.b #bPM,(a1) ; still in same phase? <3.0> <v1.3>
bne.s @RdDone ; if so, go back and wait <3.0>
@exit
swap d5 ; calculate bytes left to transfer
move.w d2,d5 ; lower word of count
addq.l #1,d5 ; undo adjustment for dbra
sub.l d5,d1 ; number of bytes transferred
rts
;
; SlowWrite
;
; Called by: Transfer
;
SlowWrite:
@WrSetup
move.l pdma5380(a4),a0 ; point to special address space
adda.w wrOffset(a4),a0 ; add in write offset, if any
@ckphase
btst.b #bREQ,sCSR(a3) ; check for REQ
beq.s @ckphase ; if no REQ, wait for synchronization
@ready
move.b zeroReg,sTCR+WrOffs(a3) ; match data out<C846/PM116/19Mar87>
move.b #iDMA,sMR+wrOffs(a3) ; set DMA mode
move.b #iDB,sICR+wrOffs(a3) ; assert data bus
btst.b #sSCSIDMAExists,G_Reserved0+3(a4) ; see if we really have the DMA chip <2.8>
beq.s @DMAdone ; if not, skip it <2.8>
move.l #iHSKEN+iINTREN,sDCTRL(a3) ; turn on hhsk <C914> <v1.3>
@DMAdone
move.b zeroReg,sDMAtx+wrOffs(a3) ; start write DMA
@test
btst.b #bPM,(a1) ; we have REQ, are we in phase ? <v1.3>
bne.s @wrContinue ; if in phase, continue <v1.3>
@wrPhaseErr
moveq.l #scPhaseErr,d0 ; return a phase error
bra.s @WrDone ; get out
@wrContinue
move.l d2,d1 ; make a copy of the byte count
subq.l #1,d2 ; decr. for DBRA <C478/10Dec86>
move.l d2,d5 ; make a copy of the byte count
swap d5 ; and get hiword in d5
;
; This is the loop for polled writes. Byte count is in d2,d5
;
@SnWr
btst.b d3,(a1) ; DRQ? <C478/10Dec86>
beq.s @SnWrChk
move.b (a2)+,(a0) ; write bytes
dbra d2,@SnWr ; decrement count
dbra d5,@SnWr
bra.s @WrDone ; we're finished <v2.3>
@SnWrChk
btst.b #bPM,(a1) ; phase OK? <C478/10Dec86>
bne.s @SnWr ; continue if it is
moveq.l #scPhaseErr,d0 ; return a phase error
bra.s @DMAOff ; we're done for now
@WrDone ; NOTE: we shouldn't turn off DMA mode before the last byte was taken.
; If the NCR chip asserts DRQ, then the peripheral got the byte.
; If the peripheral changes the bus phase, then it must have also got it.
; This section check is from <C138/29Sep86>. Modified <C780>.
btst.b #sSCSIDMAExists,G_Reserved0+3(a4) ; do we have a SCSI DMA chip ?
beq.s @noDMA ; if not, skip
@wrWait1
btst.b d3,sBSR(a3) ; check for DRQ
bne.s @DMAOff ; if DRQ, peripheral got the byte
btst.b #bPM,sBSR(a3) ; are we still in phase ?
bne.s @wrWait1 ; if so keep waiting
@noDMA
@wrWait2
btst.b d3,sBSR(a3) ; check for DRQ
bne.s @DMAOff ; if DRQ, peripheral got the byte
btst.b #bPM,sBSR(a3) ; are we still in phase ?
bne.s @wrWait2 ; if so, keep waiting
@DMAOff
move.b zeroReg,sICR+WrOffs(a3) ; disable data bus
move.b zeroReg,sMR+WrOffs(a3) ; clear DMA mode
btst.b #sSCSIDMAExists,G_Reserved0+3(a4) ; see if we really have the DMA chip <2.8>
beq.s @DMAdone2 ; if not, skip it <2.8>
move.l #iINTREN,sDCTRL(a3) ; turn off hhsk <C914> <v1.3>
@DMAdone2
swap d5 ; calculate number of bytes left to transfer
move.w d2,d5 ; low-order word of count
addq.l #1,d5 ; adjust for DBRA
sub.l d5,d1 ; number of bytes transferred
rts ; we're done
;
; VFastWriteOSS -- Virtual address interface to the SCSI DMA circuitry <v1.3>
;
; Called by: Transfer
;
; Function: This routine calls a service routine to get the physical translation
; for the virtual address/count pair passed in a2/d2. If the virtual
; data transfer cannot be performed in one DMA operation (crosses a page
; or memory bank boundary,) the virtual transfer will be completed later
; by a virtual transfer of the remaining bytes.
;
VFastWriteOSS: ;
movea.l scsiPrivate(a5),a0 ; get ptr to private storage record <v1.3>
lea.l scsiVAddr(a0),a0 ; point to record for GetPhysical routine <start>
move.l a2,d0 ; get the virtual address <v1.5>
jsr ([JStripAddress]) ; clean up that address <v1.5>
move.l d0,(a0) ; set the virtual address field <v1.5>
@translate
move.l d2,4(a0) ; set the virtual count field
moveq.l #1,d0 ; number of physical addr/count pairs
move.l d0,a1 ; set up for GetPhysical call
moveq.l #5,d0 ; GetPhysical selector
_MemoryDispatch ; perform the translation (a0 undisturbed)
bne.s @error ; if error, bail out (what to do ???)
@callPhysical
move.l 8(a0),a2 ; set up the physical address
move.l 12(a0),d2 ; set up the physical count
move.l d2,d1 ; number of bytes to transfer
movea.l jvPFW(a4),a0 ; address of fast physical write routine
jmp (a0) ; move the data
@error
if dbSymbols then
_Debugger
endif
@exit
rts ; we're done
;
; PFastWriteOSS -- Physical address interface to the SCSI DMA circuitry
;
; Called by: Transfer
;
PFastWriteOSS:
moveq.l #noErr,d0 ; noErr, yet
move.b zeroReg,sTCR+WrOffs(a3) ; match data out<C846/PM116/19Mar87>
move.b #iDMA,sMR+WrOffs(a3) ; set DMA mode <C478/10Dec86>
move.b #iDB,sICR+WrOffs(a3) ; assert data bus <C478/10Dec86>
move.l #iHSKEN,sDCTRL(a3) ; turn on hhsk <C914>
move.b zeroReg,sDMAtx+WrOffs(a3) ; start write DMA <C478/10Dec86>
@start ; blind write
move.l #$FFFFFFFF,sDTIME(a3) ; incredible Timer value <v1.5>
move.l #iTIMEEN+iINTREN+iDMAEN,sDCTRL(a3) ; enable true DMA
move.l a2,sDADDR(a3) ; set up DMA addr
move.l d2,sDCNT(a3) ; set up byte count
move.b #iIEOP+iDMA,sMR(a3) ; pDMA,EOP intr enabled
move.b #iDB,sICR(a3) ; assert the data bus
move.b zeroReg,sDMAtx(a3) ; start DMA write
bset.b #waitingForIRQ,state1(a4) ; we're DMAing, so bail and wait for intr <v1.5>
@exit
rts
PFastWrite: ; unimplemented on all other machines
rts
;
; VFastWrite -- Same as FastWrite for the old SCSI Manager
;
; Called by: Transfer
;
VFastWrite: ; all other machines
;
; FastWrite
;
; Called by: Transfer
;
FastWrite:
;patch roll in from PatchIIciROM.a <SMx><SES>
;_________________________________________________________________________________________
; FastWriteFix - patch to FastWrite
;
; This code replaces the low level data transfer routine for fast writes in the SCSI
; manager. It is rewritten to assume psuedo-dma is always on, and to do the device
; synchronization (looking for *REQ and DRQ), after loading a data byte into the
; output register of the 5380. We don't have to worry about zero-byte transfers. They
; are filtered out in the calling routine (Transfer).
;
; Entry: d2 = number of bytes to transfer
; a1 = addr of sBSR(a3) - by convention, and used by bus error handler
; a2 = ptr to data buffer to transfer
; a3 = base addr of NCR 53C80
; a4 = ptr to SCSI globals
;
; Exit: d1 = number of bytes actually transfered. This value is only good if
; the transfer was good with no errors. It is inaccurate when an
; error aborts the transfer.
;This code is intended for use with 5380 ONLY, so check to make sure we <SMx><SES>
;need to do it. Note that we're assuming that SCSIExists implies a 5380. <SMx><SES>
TestFor SCSIExists ; <SMx><SES>
beq @Done ; don't do it if we're not using a 5380 <SMx><SES>
move.l hhsk5380(a4),a0 ; point to addr for hardware handshaking
adda.w wrOffset(a4),a0 ; add in write offset
move.l d2,d1 ; save to return number of bytes transfered
; Pre-load the NCR 53C80's output register with a byte of data. If we are in
; the middle of a multi-block write, *ACK is currently asserted. Writing a byte
; to the output register will release *ACK, completing the handshaking, allowing
; the target to assert *REQ. Is there a chance We do not need to check for DRQ at this point (to see
; if the chip is ready for the next byte), because all data out routines always
; wait to make sure the last byte got out.
sub.l #1,d2 ; dec number of bytes to xfer
move.b (a2)+,(a0) ; write data byte to output register
; With *ACK released, determine if the target is in sync. We cannot look for
; *REQ to be asserted, because the target may have already accepted the data byte
; and released *REQ at this point. We can sync on DRQ which will signal when
; the NCR 53C80 is ready to accept a data byte, meaning a *REQ from the target
; must have already occurred and our data byte was taken.
@syncWait
btst.b #bDMAR,(a1) ; check bus & status reg for DRQ
bne.s @doWrite ; DRQ present - sync-ed up so proceed
btst.b #bREQ,sCSR(a3) ; no DRQ - is *REQ present ?
beq.s @syncWait ; no *REQ yet - wait for sync
btst.b #bPM,(a1) ; with *REQ, check phase lines
bne.s @syncWait ; still in data out phase - wait
moveq.l #0,d1 ; out of phase - did not xfer any bytes
moveq.l #scPhaseErr,d0 ; return error
bra.s @Done ; exit
; Perform the write to the SCSI chip. First align the bytes to longs, then
; align them to 32 byte chunks. Transfer the bulk of the data in 32 byte
; blocks.
; Reg d2.l = number of bytes to move
@doWrite
cmpi.l #3,d2 ; check for very short copy
bls.s @veryShort ; skip alignment if very short
move.l a2,d0 ; get addr of data buffer
andi.l #$00000003,d0 ; check for long word alignment
beq.s @Aligned ; if no alignment needed
subq.l #4,d0 ; bias by 4 to get correct index
jmp @Aligned(d0.w*2) ; do the alignment
move.b (a2)+,(a0) ; move a byte
move.b (a2)+,(a0) ; move a byte
move.b (a2)+,(a0) ; move a byte
@Aligned
add.l d0,d2 ; adjust the byte count (d0 = neg)
move.l d2,d4 ; save tail byte count
lsr.w #2,d2 ; adjust to number of longs to move
moveq.l #7,d0 ; mask for starting index
and.l d2,d0 ; number of long words to move first
neg.w d0 ; negate to index backwards
lsr.l #3,d2 ; number of 32 byte blocks to move
move.l d2,d3 ; get number of 32*64K byte blks to move
swap d3 ; count in low word
jmp @CopyStart(d0.w*2) ; jump into the loop
@CopyLoop move.l (a2)+,(a0) ; move a 32 byte block of data....
move.l (a2)+,(a0) ; ... 4 bytes at a time
move.l (a2)+,(a0)
move.l (a2)+,(a0)
move.l (a2)+,(a0)
move.l (a2)+,(a0)
move.l (a2)+,(a0)
move.l (a2)+,(a0)
@CopyStart dbra d2,@CopyLoop ; loop in chunks of 32 bytes
dbra d3,@CopyLoop ; loop in chunks of 32*64K bytes
andi.l #$00000003,d4 ; check for tail alignment
move.l d4,d2 ; d2 = number of bytes remaining
@veryShort
neg.w d2 ; negate to index backwards
jmp @Remaining(d2.w*2) ; write remaining bytes
move.b (a2)+,(a0) ; move a byte
move.b (a2)+,(a0) ; move a byte
move.b (a2)+,(a0) ; move a byte
@Remaining
; Before exiting this routine, make sure that the peripheral has actually accepted
; the data byte. Wait for a DRQ (meaning the SCSI chip is ready for another byte)
; before exiting.
@DoneWait
moveq.l #0,d0 ; set good return
btst.b #bDMAR,(a1) ; check for DRQ (a1 = sBSR(a3))
bne.s @Done ; if DRQ, peripheral got the byte
btst.b #bREQ,sCSR(a3) ; no DRQ - is *REQ present ?
beq.s @DoneWait ; no *REQ yet - wait for it
btst.b #bPM,(a1) ; are we still in phase ?
bne.s @DoneWait ; if so, keep waiting
@Done
rts ; we're done
;end FastWrite patch roll in from PatchIIciROM.a <SMx><SES>
;
; FastWriteOSS -- Old SCSI Mgr virtual address interface to the SCSI DMA circuitry
;
; Called by: Transfer
;
; NOTE:
; Because the SCSI Bus Error handler counts on the a6 linkage that is in
; effect when this routine is called, the local storage needed by this routine
; to perform a DMA operation is simply allocated by moving the stack pointer.
;
; After allocating the local storage, the stack appears as follows:
;
; SP ---> virtAddress \ The stack pointer points to the
; virtCount \ parameter block for the GetPhysical call.
; physAddress / (All values are long words.)
; physCount /
; - reserved - Extra long word
; cleanAddress Pushed after StripAddress
; returnAddr <--- SP on entry
; ...
;
FastWriteOSS:
move.l a2,d0 ; make the buffer address 32-bit clean
jsr ([JStripAddress]) ; clean up that address
move.l d0,-(sp) ; save the 32-bit clean address <4>
lea.l -AddLocalSize(sp),sp ; allocate additional storage <v1.7start>
move.l d0,vAddr(sp) ; set the virtual address field <4>
move.l d2,vCount(sp) ; set the virtual count field <4>
movea.l d0,a0 ; virtual address <4>
movea.l d2,a1 ; virtual count <4>
moveq.l #2,d0 ; LockMemory selector <4>
_MemoryDispatch ; lock the buffer (a0 undisturbed) <4>
bne.w @badAddrError ; if error, then bail out <4>
movea.l sp,a0 ; a0 -> logical/physical param block
movea.w #1,a1 ; number of physical addr/count pairs
moveq.l #5,d0 ; GetPhysical selector
_MemoryDispatch ; perform the translation (a0 undisturbed)
bne.w @badAddrError ; if error, then bail out <v1.7>
@ckphase
btst.b #bREQ,sCSR(a3) ; check for REQ
beq.s @ckphase ; if no REQ, wait (synchronization)
@ready
move.b zeroReg,sTCR+WrOffs(a3) ; match data out<C846/PM116/19Mar87>
move.b #iDMA,sMR+WrOffs(a3) ; set DMA mode <C478/10Dec86>
move.b #iDB,sICR+WrOffs(a3) ; assert data bus <C478/10Dec86>
moveq.l #iHSKEN,d5 ; <v1.7>
move.l d5,sDCTRL(a3) ; turn on hhsk <C914> <start>
move.b zeroReg,sDMAtx+WrOffs(a3) ; start write DMA <C478/10Dec86>
@wait
btst.b d3,sBSR(a3) ; is DRQ asserted ?
bne.s @start ; if so, ACK must be true (pDMA)
btst.b #bREQ,sCSR(a3) ; check for REQ for phase check
beq.s @wait ; no REQ yet
btst.b #bPM,sBSR(a3) ; are we still in phase ? <end>
bne.s @wait ; keep waiting <v1.7>
@wrPhaseErr
moveq.l #scPhaseErr,d0 ; return a phase error
bra.w @WrDone ; get out
@start ; at this point, d0 = noErr <v1.7start>
bset.b #doingDMA,state1(a4) ; we're DMAing, so don't bother the chip <5>
move.l G_Reserved1(a4),sDTIME(a3) ; set Timer value <5>
moveq.l #iTIMEEN+iINTREN+iDMAEN,d5 ;
move.l d5,sDCTRL(a3) ; enable true DMA
move.l pAddr(a0),sDADDR(a3) ; set up DMA addr
move.l pCount(a0),sDCNT(a3) ; set up byte count
move.b #iIEOP+iDMA,sMR(a3) ; pDMA,EOP intr enabled
move.b #iDB,sICR(a3) ; assert the data bus
move.b zeroReg,sDMAtx(a3) ; start DMA write
;
; The pCount field is used to flag the need to move more data.
; If pCount is zero, it reflects that no more data needs to be moved.
; If pCount is nonzero, a translation will be performed, leaving pCount nonzero.
;
move.l vCount(a0),pCount(a0) ; any bytes left to transfer ?
beq.s @noPreflight ; if not, nothing to translate
movea.w #1,a1 ; number of physical addr/count pairs
moveq.l #5,d0 ; GetPhysical selector
_MemoryDispatch ; perform the translation (a0 undisturbed)
bne.w @badAddrError ; if error, then bail out
@noPreflight
movea.l OSS,a1 ; point to base of OSS chip
@waitForIntr
btst.b #OSSIntSCSI-8,OSSIntStat(a1) ; check for a SCSI interrupt
beq.s @waitForIntr ; wait for a SCSI interrupt
move.l sDCTRL(a3),d5 ; check for success
andi.w #iDMABERR+iTIMEP,d5 ; DMA bus error or watchdog timeout ?
bne.s @badAddrError ; if so, handle it
tst.l sDCNT(a3) ; did we transfer all the data ?
bne.s @badAddrError ; if not, report an error
move.b zeroReg,sMR(a3) ; clear EOP interrupt (and turn off pDMA)
tst.b sRESET(a3) ; clear SCSI interrupt
@chkDone
tst.l pCount(a0) ; were any bytes left to transfer ? <end>
bne.s @start ; continue until all bytes transferred <v1.7>
move.l d2,d1 ; return number of bytes transferred
@WrDone ; NOTE: we shouldn't turn off DMA mode before the last byte was taken.
; If the NCR chip asserts DRQ, then the peripheral got the byte.
; If the peripheral changes the bus phase, then it must have also got it.
; This section check is from <C138/29Sep86>. Modified <C780>.
btst.b #bACK,sBSR(a3) ; check for ACK <3.0>
beq.s @DMAOff ; if no ACK, we're done <3.0>
@ACK
@wfnREQ
btst.b #bREQ,sCSR(a3) ; test for *REQ <3.0>
beq.s @DMAOff ; if it's gone, we're done <3.0>
btst.b #bPM,sBSR(a3) ; still in same phase? <3.0> <v1.7>
bne.s @WrDone ; if so, go back and wait <3.0>
@DMAOff
move.b zeroReg,sMR+WrOffs(a3) ; clear DMA mode
move.b zeroReg,sICR+WrOffs(a3) ; disable data bus
moveq.l #iINTREN,d5 ; <v1.7>
move.l d5,sDCTRL(a3) ; turn off hhsk <C914> <v1.3> <start>
bclr.b #doingDMA,state1(a4) ; we're finished DMAing <5>
lea.l AddLocalSize(sp),sp ; deallocate additional storage on the stack
movea.l (sp)+,a0 ; set virtual address <4>
movea.l d2,a1 ; set virtual count <4>
move.w d0,-(sp) ; save result from SCSI I/O <4>
moveq.l #3,d0 ; UnlockMemory selector <4>
_MemoryDispatch ; unlock the buffer (a0 undisturbed) <4>
move.w (sp)+,d0 ; restore original result <4>
rts
@badAddrError
moveq.l #scBusTOErr,d0 ; return a SCSI bus timeout error <end>
bra.s @DMAOff ; <v1.7>
rts ; we're done
;
; VFastReadOSS -- Virtual address interface to the DMA circuitry <v1.3>
;
; Called by: Transfer
;
; Function: This routine calls a service routine to get the physical translation
; for the virtual addr/count pair that is passed in a2/d2. If the virtual
; data transfer cannot be performed in one DMA operation (crosses a page or
; memory bank boundary,) the virtual transfer will be completed later by
; a virtual transfer of the remaining bytes.
;
VFastReadOSS:
movea.l scsiPrivate(a5),a0 ; get ptr to private storage record <v1.3>
lea.l scsiVAddr(a0),a0 ; point to record for GetPhysical routine <start>
move.l a2,d0 ; get the virtual address <v1.5>
jsr ([JStripAddress]) ; clean up that address <v1.5>
move.l d0,(a0) ; set the virtual address field <v1.5>
@translate
move.l d2,4(a0) ; set the virtual count field
moveq.l #1,d0 ; number of physical address/count pairs
move.l d0,a1 ; set up for GetPhysical call
moveq.l #5,d0 ; GetPhysical selector
_MemoryDispatch ; perform the translation (a0 undisturbed)
bne.s @error ; if error, then bail out (what to do ???)
@callPhysical
move.l 8(a0),a2 ; set up the physical address
move.l 12(a0),d2 ; set up the physical count
move.l d2,d1 ; number of bytes to transfer
movea.l jvPFR(a4),a0 ; address of fast physical data transfer routine
jmp (a0) ; move the data
@error
if dbSymbols then
_Debugger
endif
@exit
rts
;
; PFastRead -- Physical address interface to the DMA circuitry
;
; Called by: Transfer
;
PFastReadOSS:
moveq.l #noErr,d0 ; noErr, yet
@start
move.l #$FFFFFFFF,sDTIME(a3) ; incredible Timer value <v1.5>
move.l #iTIMEEN+iINTREN+iDMAEN,sDCTRL(a3) ; enable true DMA
move.l a2,sDADDR(a3) ; set up DMA addr
move.l d2,sDCNT(a3) ; set up byte count
move.b #iIEOP+iDMA,sMR(a3) ; pDMA,EOP intr enabled
move.b zeroReg,sIDMArx(a3) ; start DMA read
bset.b #waitingForIRQ,state1(a4) ; we're DMAing, so bail and wait for intr <v1.5>
@exit
rts
;
; PFastRead -- Physical address interface to the DMA circuitry
;
; Called by: Transfer
;
PFastRead: ; all other machines
rts ; unimplemented
;
; VFastRead -- For all other machines, same as old SCSI Mgr FastRead routine
;
; Called by: Transfer
;
VFastRead:
;
; FastRead
;
; Called by: Transfer
;
FastRead:
@RdSetup
move.l hhsk5380(a4),a0 ; use the global <C406/12Nov86>
adda.l #sIDR,a0 ; input data offset <C406/12Nov86>
@wait
btst.b d3,(a1) ; DRQ? <C478/10Dec86>
bne.s @start ; have DRQ, so let's go
btst.b #bREQ,sCSR(a3) ; test for REQ in case of phase error
beq.s @wait ; no REQ, so wait
@ckphase
btst.b #bPM,(a1) ; phase OK? <C478/10Dec86>
bne.s @start ; continue if in phase
@RdPhaseErr
moveq.l #scPhaseErr,d0 ; return error
bra.w @exit
@start
move.l d2,d1 ; copy of transfer count
moveq.l #3,d4 ; mask for long alignment
cmp.l d4,d2 ; enough bytes to align?
bhi.s @over3 ; more than three bytes
moveq.l #-1,d5 ; fudge to calculate normally
moveq.l #-1,d6 ; more fudging
bra.s @BlRdRmdr ; do them one at a time
@over3
move.l a2,d5 ; get destination address
neg.l d5 ; negate to get odd byte count
and.l d4,d5 ; mask off to get 0-3 count
sub.l d5,d2 ; d2 = count after alignment
bra.s @1 ; in case it's already aligned
@0
move.b (a0),(a2)+ ; do the leading unaligned bytes
@1
dbra d5,@0 ; loop until long-word aligned
move.l d2,d5 ; copy of the count
lsr.l #5,d5 ; divide by 32 <A356/06Nov86>
bne.s @over32 ; more than 32 bytes left
moveq.l #-1,d5 ; fudge to calculate normally
moveq.l #-1,d6 ; more fudging
bra.s @BlRdRmdr ; get the remaining bytes
@over32
subq.l #1,d5 ; adjust for dbra
move.l d5,d6 ; high order word of count
swap d6 ; number of 32-byte moves
moveq.l #$1F,d4 ; 32-1 <A356/06Nov86>
and.l d4,d2 ; remainder count after 32-byte moves
@BlRd32 ; <A356/06Nov86>
move.l (a0),(a2)+ ; do 8 aligned longs (32 bytes)
move.l (a0),(a2)+
move.l (a0),(a2)+
move.l (a0),(a2)+
move.l (a0),(a2)+
move.l (a0),(a2)+
move.l (a0),(a2)+
move.l (a0),(a2)+
dbra d5,@BlRd32 ; low word of # of 32-byte moves
dbra d6,@BlRd32 ; high order word
bra.s @BlRdRmdr
@BlRdSingle
move.b (a0),(a2)+
@BlRdRmdr
dbra d2,@BlRdSingle
swap d6 ; calculate bytes left to transfer
move.w d5,d6 ; get low order word
addq.l #1,d6 ; groups of 32
lsl.l #5,d6 ; multiply by 32
ext.l d2 ; make d2 a long
addq.l #1,d2 ; single bytes left
add.l d2,d6 ; add to total
sub.l d6,d1 ; result
@RdDone
btst.b #bACK,sBSR(a3) ; check for ACK <3.0>
beq.s @exit ; if no ACK, we're done <3.0>
@ACK
@wfnREQ
btst.b #bREQ,sCSR(a3) ; test for *REQ <3.0>
beq.s @exit ; if it's gone, we're done <3.0>
btst.b #bPM,(a1) ; still in same phase? <3.0> <v1.3>
bne.s @RdDone ; if so, go back and wait <3.0>
@exit
rts
;
; FastReadOSS -- Old SCSI Mgr virtual address interface to the DMA circuitry
;
; Called by: Transfer
;
; NOTE:
; Because the SCSI Bus Error handler counts on the a6 linkage that is in
; effect when this routine is called, the local storage needed by this routine
; to perform a DMA operation is simply allocated by moving the stack pointer.
;
; After allocating the local storage, the stack appears as follows:
;
; SP ---> virtAddress \ The stack pointer points to the
; virtCount \ parameter block for the GetPhysical call.
; physAddress / (All values are long words.)
; physCount /
; - reserved - Extra long word
; cleanAddress Pushed after StripAddress
; returnAddr <--- SP on entry
; ...
;
FastReadOSS:
move.l a2,d0 ; make the address 32-bit clean
jsr ([JStripAddress]) ; clean up that address
move.l d0,-(sp) ; save the 32-bit clean virtual address <4>
lea.l -AddLocalSize(sp),sp ; allocate additional storage <v1.7start>
move.l d0,vAddr(sp) ; set the virtual address <4>
move.l d2,vCount(sp) ; set the virtual count <4>
movea.l d0,a0 ; virtual address <4>
movea.l d2,a1 ; virtual count <4>
moveq.l #2,d0 ; LockMemory selector <4>
_MemoryDispatch ; lock the buffer (a0 undisturbed) <4>
bne.w @badAddrError ; if error, then bail out <4>
movea.l sp,a0 ; a0 -> logical/physical param block <4>
movea.w #1,a1 ; number of physical address/count pairs
moveq.l #5,d0 ; GetPhysical selector
_MemoryDispatch ; perform the translation (a0 undisturbed)
bne.w @badAddrError ; if error, then bail out
@wait
btst.b d3,sBSR(a3) ; DRQ? <C478/10Dec86>
bne.s @start ; have DRQ, so let's go
btst.b #bREQ,sCSR(a3) ; test for REQ in case of phase error
beq.s @wait ; no REQ, so wait <end>
btst.b #bPM,sBSR(a3) ; phase OK? <C478/10Dec86> <v1.7>
bne.s @start ; continue if in phase
@RdPhaseErr
moveq.l #scPhaseErr,d0 ; return error
bra.w @exit
@start ; at this point, d0 = noErr <v1.7start>
bset.b #doingDMA,state1(a4) ; we're DMAing, so don't bother the chip <5>
move.l G_Reserved1(a4),sDTIME(a3) ; set Timer value <5>
moveq.l #iTIMEEN+iINTREN+iDMAEN,d5 ;
move.l d5,sDCTRL(a3) ; enable true DMA
move.l pAddr(a0),sDADDR(a3) ; set up DMA addr
move.l pCount(a0),sDCNT(a3) ; set up byte count
move.b #iIEOP+iDMA,sMR(a3) ; pDMA,EOP intr enabled
move.b zeroReg,sIDMArx(a3) ; start DMA read
;
; The pCount field is used to flag the need to move more data.
; If pCount is zero, it reflects that no more data needs to be moved.
; If pCount is nonzero, a translation will be performed, leaving pCount nonzero.
;
move.l vCount(a0),pCount(a0) ; any bytes left to transfer ?
beq.s @noPreflight ; if not, nothing to translate
movea.w #1,a1 ; number of physical address/count pairs
moveq.l #5,d0 ; GetPhysical selector
_MemoryDispatch ; perform the translation (a0 undisturbed)
bne.w @badAddrError ; if error, then bail out
@noPreflight
movea.l OSS,a1 ; point to base of OSS chip
@waitForIntr
btst.b #OSSIntSCSI-8,OSSIntStat(a1) ; check for a SCSI interrupt
beq.s @waitForIntr ; wait for a SCSI interrupt
move.l sDCTRL(a3),d5 ; check for success
andi.w #iDMABERR+iTIMEP,d5 ; DMA bus error or watchdog timeout ?
bne.s @badAddrError ; if so, handle it
tst.l sDCNT(a3) ; did we transfer all the data ?
bne.s @badAddrError ; if not, report an error
move.b zeroReg,sMR(a3) ; clear the EOP interrupt, turn off pDMA
tst.b sRESET(a3) ; clear SCSI interrupt
move.b #iDMA,sMR(a3) ; turn on pDMA
move.b zeroReg,sIDMArx(a3) ; kick the pDMA mode
@chkDone
tst.l pCount(a0) ; any bytes left to transfer ? <end>
bne.s @start ; keep going until all bytes transferred
move.l d2,d1 ; return number of bytes transferred <v1.7>
@RdDone
btst.b #bACK,sBSR(a3) ; check for ACK <3.0>
beq.s @exit ; if no ACK, we're done <3.0>
@ACK
@wfnREQ
btst.b #bREQ,sCSR(a3) ; test for *REQ <3.0>
beq.s @exit ; if it's gone, we're done <3.0>
btst.b #bPM,sBSR(a3) ; still in same phase? <3.0> <v1.3><v1.7>
bne.s @RdDone ; if so, go back and wait <3.0>
@exit
bclr.b #doingDMA,state1(a4) ; we're finished DMAing <5>
lea.l AddLocalSize(sp),sp ; deallocate additional storage <v1.7>
movea.l (sp)+,a0 ; set virtual address <4>
movea.l d2,a1 ; set buffer length <4>
move.w d0,-(sp) ; save result from SCSI I/O <4>
moveq.l #3,d0 ; UnlockMemory selector <4>
_MemoryDispatch ; unlock the buffer (a0 undisturbed) <4>
move.w (sp)+,d0 ; restore original result <4>
rts
@badAddrError
moveq.l #scBusTOErr,d0 ; report a "bus timeout error" <v1.7>
bra.s @exit ; <end>
rts
;
; SlowComp <v1.3>
; <start>
; Called by: Transfer
;
SlowComp:
@CompSetup
move.l pdma5380(a4),a0 ; use the global <C406/12Nov86>
adda.l #sIDR,a0 ; input data offset <C406/12Nov86>
subq.l #1,d2 ; decr. for DBRA <C478/10Dec86>
move.l d2,d5 ; make a copy of the byte count
swap d5 ; and get hiword in d5
@wait
btst.b #bDMAR,(a1) ; DRQ ?
bne.s @SnComp ; if so, start the transfer
btst.b #bREQ,sCSR(a3) ; look for REQ
beq.s @wait ; can't check phase until REQ is asserted
btst.b #bPM,(a1) ; we have REQ, do we have a phase match ?
beq.s @CompPhaseErr ; if not, bail out with an error
@SnComp ; Slow compare loop. Byte count in d2,d5
btst.b #bDMAR,(a1) ; DRQ? <C478/10Dec86>
beq.s @SnCompChk ; no, so check phase <A244/27Oct86>
move.b (a0),d3 ; get data byte <29Oct85>
cmp.b (a2)+,d3 ; same? <29Oct85>
beq.s @SnComp1 ; if so, continue
moveq.l #scCompareErr,d0 ; record compare error <29Oct85>
@SnComp1
dbra d2,@SnComp ; repeat
dbra d5,@SnComp ; repeat
bra.s @RdDone ; let's get out of here
@SnCompChk
bsr.w NewPhaseCheck ; check more carefully for phase match <1>
bne.s @SnComp ; continue if it is
@CompPhaseErr
moveq.l #scPhaseErr,d0 ; return error
bra.s @exit ; let's get out here
@RdDone
btst.b #bACK,sBSR(a3) ; check for ACK <3.0>
beq.s @exit ; if no ACK, we're done <3.0>
@ACK
@wfnREQ
btst.b #bREQ,sCSR(a3) ; test for *REQ <3.0>
beq.s @exit ; if it's gone, we're done <3.0>
btst.b #bPM,(a1) ; still in same phase? <3.0>
bne.s @RdDone ; if so, go back and wait <3.0>
@exit
swap d5 ; calculate bytes left to transfer
move.w d2,d5 ; lower word of count
addq.l #1,d5 ; undo adjustment for DBRA
sub.l d5,d1 ; number of bytes transferred
moveq.l #bDMAR,d3 ; restore d3
rts
;
; FastComp
;
; Called by: Transfer
;
FastComp:
@CompSetup
movea.l hhsk5380(a4),a0 ; use the global
adda.l #sIDR,a0 ; input data register offset
subq.l #1,d2 ; decr. for DBRA <C478/10Dec86>
move.l d2,d5 ; make a copy of the byte count
swap d5 ; and get hiword in d5
@wait
btst.b #bDMAR,(a1) ; DRQ ?
bne.s @BlCmp ; have DRQ, so let's go
btst.b #bREQ,sCSR(a3) ; test for REQ in case of phase error
beq.s @wait ; no REQ, so wait
@ckPhase
btst.b #bPM,(a1) ; phase OK ?
bne.s @BlCmp ; continue if in phase
@RdPhaseErr
moveq.l #scPhaseErr,d0 ; return error
bra.s @exit ; let's get out here
@BlCmp
move.b (a0),d3 ; blind compare <29Oct85> -- no optimization
cmp.b (a2)+,d3
beq.s @BlCmp1
moveq.l #scCompareErr,d0 ; record compare error
@BlCmp1
dbra d2,@BlCmp
dbra d5,@BlCmp
@RdDone
btst.b #bACK,sBSR(a3) ; check for ACK <3.0>
beq.s @exit ; if no ACK, we're done <3.0>
@ACK
@wfnREQ
btst.b #bREQ,sCSR(a3) ; test for *REQ <3.0>
beq.s @exit ; if it's gone, we're done <3.0>
btst.b #bPM,(a1) ; still in same phase? <3.0>
bne.s @RdDone ; if so, go back and wait <3.0>
@exit
swap d5 ; calculate bytes left to transfer
move.w d2,d5 ; lower word of count
addq.l #1,d5 ; undo adjustment for DBRA
sub.l d5,d1 ; number of bytes transferred <end>
moveq.l #bDMAR,d3 ; restore d3 <v1.3>
rts
;
; This "improved" phase checking routine will fix the CD-ROM problem on Zone5. <1>
; On the SCSI DMA chip it's possible to have a DRQ without a phase match, and if an <start>
; interrupt occurs between checks of the BSR register, it appears that a disasterous
; phase change has occurred.
; To fix this problem, a snapshot is taken of the BSR register. If either DRQ or PM
; are set, then it is okay to continue. If both are cleared, a phase error has occurred.
; If DRQ or PM are set, the Zero flag is cleared.
; If neither are set, the Zero flag is set.
;
; Destroys d6
;
NewPhaseCheck:
moveq.l #iDMAR+iPM,d6 ; if DRQ or PM is set, all is well
and.b sBSR(a3),d6 ; get a snapshot of the register <end>
rts ; if either is set, then Z=0 <1>
ENDWITH
END