At $Ids to all files. Have the sequencer use DMA to tranfer its SCB

(SCSI control block) instead of having the host PIO it down.  Also
reimplement WDTR and SDTR optimization to remove code in the sequencer
and place the responsibility of knowing when to initiate SDTR or WDTR
on the kernel driver.  This vastly shortens the sequencer program yet
yeilds the same performance.

2 files changed, 128 insertions, 109 deletions

diff --git a/sys/gnu/misc/aic7xxx/aic7xxx.c b/sys/gnu/misc/aic7xxx/aic7xxx.c
index 417a352..8077ac8 100644
--- a/sys/gnu/misc/aic7xxx/aic7xxx.c
+++ b/sys/gnu/misc/aic7xxx/aic7xxx.c
@@ -25,6 +25,8 @@
  *
  *  A <label> is an <undef-sym> ending in a colon.  Spaces, tabs, and commas
  *  are token separators.
+ *	
+ *	$Id$
  */
 
 /* #define _POSIX_SOURCE	1 */
diff --git a/sys/gnu/misc/aic7xxx/aic7xxx.seq b/sys/gnu/misc/aic7xxx/aic7xxx.seq
index d1ed1e1..b02c778 100644
--- a/sys/gnu/misc/aic7xxx/aic7xxx.seq
+++ b/sys/gnu/misc/aic7xxx/aic7xxx.seq
@@ -1,6 +1,6 @@
 # @(#)aic7xxx.seq 1.32 94/11/29 jda
 #
-# Adaptec 274x/284x/294x device driver for Linux.
+# Adaptec 274x/284x/294x device driver for Linux and FreeBSD.
 # Copyright (c) 1994 The University of Calgary Department of Computer Science.
 # 
 # This program is free software; you can redistribute it and/or modify
@@ -16,8 +16,14 @@
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+#
+
+# FreeBSD, Twin, Wide, 2 command per target support, and other optimizations
+# provided by Justin T. Gibbs (gibbs@FreeBSD.org)
+#
+#	$Id$
 
-VERSION AIC7XXX_SEQ_VERSION 1.32
+VERSION AIC7XXX_SEQ_VERSION 1.5
 
 SCBMASK		= 0x1f
 
@@ -70,14 +76,30 @@ SCSICONF_B	= 0x5b
 #  The two reserved bytes at SCBARRAY+1[23] are expected to be set to
 #  zero, and the reserved bit in SCBARRAY+0 is used as an internal flag
 #  to indicate whether or not to reload scatter-gather parameters after
-#  a disconnect.
+#  a disconnect.  We also use bits 6 & 7 to indicate whether or not to
+#  initiate SDTR or WDTR repectively when starting this command.
 #
 SCBARRAY+0	= 0xa0
+
+DISCONNECTED	= 0x04
+NEEDDMA		= 0x08
+SG_LOAD		= 0x10
+NEEDSDTR	= 0x40
+NEEDWDTR	= 0x80
+
 SCBARRAY+1	= 0xa1
 SCBARRAY+2	= 0xa2
 SCBARRAY+3	= 0xa3
+SCBARRAY+4	= 0xa4
+SCBARRAY+5	= 0xa5
+SCBARRAY+6	= 0xa6
 SCBARRAY+7	= 0xa7
+SCBARRAY+8	= 0xa8
+SCBARRAY+9	= 0xa9
+SCBARRAY+10	= 0xaa
 SCBARRAY+11	= 0xab
+SCBARRAY+12	= 0xac
+SCBARRAY+13	= 0xad
 SCBARRAY+14	= 0xae
 SCBARRAY+15	= 0xaf
 SCBARRAY+16	= 0xb0
@@ -90,14 +112,16 @@ SCBARRAY+22	= 0xb6
 SCBARRAY+23	= 0xb7
 SCBARRAY+24	= 0xb8
 SCBARRAY+25	= 0xb9
+SCBARRAY+26	= 0xba
 
-SIGNAL_0	= 0x01				# unknown scsi bus phase
-SIGNAL_1	= 0x11				# message reject
-SIGNAL_2	= 0x21				# no IDENTIFY after reconnect
-SIGNAL_3	= 0x31				# no cmd match for reconnect
-SIGNAL_4	= 0x41				# SDTR -> SCSIRATE conversion
-STATUS_ERROR    = 0x51
-SIGNAL_WDTR	= 0x61
+BAD_PHASE	= 0x01				# unknown scsi bus phase
+SEND_REJECT	= 0x11				# sending a message reject
+NO_IDENT	= 0x21				# no IDENTIFY after reconnect
+NO_MATCH	= 0x31				# no cmd match for reconnect
+MSG_SDTR	= 0x41				# SDTR message recieved
+MSG_WDTR	= 0x51				# WDTR message recieved
+MSG_REJECT	= 0x61				# Reject message recieved
+BAD_STATUS	= 0x71				# Bad status from target
 
 #  The host adapter card (at least the BIOS) uses 20-2f for SCSI
 #  device information, 32-33 and 5a-5f as well. As it turns out, the
@@ -107,10 +131,10 @@ SIGNAL_WDTR	= 0x61
 #  SCSIRATE).  The kernel driver will enable synchronous negotiation
 #  for all targets that have a value other than 0 in the lower four
 #  bits of the target scratch space.  This should work irregardless of
-#  whether the bios has been installed. NEEDSDTR has one bit per target 
-#  indicating if an SDTR message is needed for that device - this will 
-#  be set initially (based on a search through the target scratch space), 
-#  as well as after a bus reset condition.
+#  whether the bios has been installed. NEEDWDTR and NEEDSDTR are the top
+#  two bits of the SCB control byte.  The kernel driver will set these
+#  when a WDTR or SDTR message should be sent to the target the SCB's 
+#  command references.
 #
 #  The high bit of DROPATN is set if ATN should be dropped before the ACK
 #  when outb is called.  REJBYTE contains the first byte of a MESSAGE IN
@@ -133,9 +157,6 @@ REJBYTE		= 0x31
 DISC_DSB_A	= 0x32
 DISC_DSB_B	= 0x33
 
-NEEDWDTR_A	= 0x34
-NEEDWDTR_B	= 0x35
-
 MSG_LEN		= 0x36
 MSG_START+0	= 0x37
 MSG_START+1	= 0x38
@@ -146,13 +167,16 @@ MSG_START+5	= 0x3c
 -MSG_START+0	= 0xc9				# 2's complement of MSG_START+0
 
 ARG_1		= 0x4c				# sdtr conversion args & return
+BUS_16_BIT	= 0x01
 RETURN_1	= 0x4c
 
 SIGSTATE	= 0x4d				# value written to SCSISIGO
-NEEDSDTR_A	= 0x4e				# send SDTR message, 1 bit/trgt
-NEEDSDTR_B	= 0x4f
 
-SG_SIZEOF	= 0x8 				# sizeof(struct scatterlist)
+# Linux users should use 0xc (12) for SG_SIZEOF
+SG_SIZEOF	= 0x8 				# sizeof(struct ahc_dma)
+#SG_SIZEOF	= 0xc 				# sizeof(struct scatterlist)
+SCB_SIZEOF	= 0x13				# sizeof SCB to DMA (19 bytes)
+
 SG_NOLOAD	= 0x50				# load SG pointer/length?
 SG_COUNT	= 0x51				# working value of SG count
 SG_NEXT		= 0x52				# working value of SG pointer
@@ -165,7 +189,6 @@ SCBCOUNT	= 0x56				# the actual number of SCBs
 FLAGS		= 0x57				# Device configuration flags
 TWIN_BUS	= 0x01
 WIDE_BUS	= 0x02
-CHECK_DTR	= 0x08
 SENSE		= 0x10
 ACTIVE_MSG	= 0x20
 IDENTIFY_SEEN	= 0x40
@@ -189,13 +212,60 @@ start2:
 	test	SCSISIGI,0x4	jnz reselect	# BSYI
 	test	QINCNT,SCBMASK	jz start
 
-#  We have at least one queued SCB now.  Set the SCB pointer
-#  from the FIFO so we see the right bank of SCB registers,
-#  then set SCSI options and set the initiator and target
-#  SCSI IDs.
+# We have at least one queued SCB now.  Set the SCB pointer
+# from the FIFO so we see the right bank of SCB registers,
+# then set SCSI options and set the initiator and target
+# SCSI IDs.
 #
 	mov	SCBPTR,QINFIFO
 
+# If the control byte of this SCB has the NEEDDMA flag set, we have
+# yet to DMA it from host memory
+
+test	SCBARRAY+0,NEEDDMA	jz test_busy
+	clr	HCNT+2
+	clr	HCNT+1
+	mvi	HCNT+0,SCB_SIZEOF
+
+	mvi	A,4
+	mvi	DINDEX,HADDR
+	mvi	SCBARRAY+26	call bcopy
+
+	mvi	DFCNTRL,0xd			# HDMAEN|DIRECTION|FIFORESET
+
+#  Wait for DMA from host memory to data FIFO to complete, then disable
+#  DMA and wait for it to acknowledge that it's off.
+#
+scb_load1:
+	test	DFSTATUS,0x8	jz scb_load1	# HDONE
+
+	clr	DFCNTRL				# disable DMA
+scb_load2:
+	test	DFCNTRL,0x8	jnz scb_load2	# HDMAENACK
+
+# Copy the SCB from the FIFO to  the SCBARRAY
+
+	mov	SCBARRAY+0, DFDAT
+	mov	SCBARRAY+1, DFDAT
+	mov	SCBARRAY+2, DFDAT
+	mov	SCBARRAY+3, DFDAT
+	mov	SCBARRAY+4, DFDAT
+	mov	SCBARRAY+5, DFDAT
+	mov	SCBARRAY+6, DFDAT
+	mov	SCBARRAY+7, DFDAT
+	mov	SCBARRAY+8, DFDAT
+	mov	SCBARRAY+9, DFDAT
+	mov	SCBARRAY+10, DFDAT
+	mov	SCBARRAY+11, DFDAT
+	mov	SCBARRAY+12, DFDAT
+	mov	SCBARRAY+13, DFDAT
+	mov	SCBARRAY+14, DFDAT
+	mov	SCBARRAY+15, DFDAT
+	mov	SCBARRAY+16, DFDAT
+	mov	SCBARRAY+17, DFDAT
+	mov	SCBARRAY+18, DFDAT
+	and	SCBARRAY+0, 0xf7
+   
 # See if there is not already an active SCB for this target.  This code
 # locks out on a per target basis instead of target/lun.  Although this
 # is not ideal for devices that have multiple luns active at the same
@@ -205,6 +275,7 @@ start2:
 # assumes that the kernel driver will clear the active flags on board 
 # initialization, board reset, and a target's SELTO.
 
+test_busy:
 	and	FUNCTION1,0x70,SCBARRAY+1
 	mov	A,FUNCTION1
 	test	SCBARRAY+1,0x88	jz test_a	# Id < 8 && A channel
@@ -228,6 +299,7 @@ test_a:
 	or	ACTIVE_A,A	# Mark the current target as busy
 
 start_scb:
+	or	SCBARRAY+0,NEEDDMA
 	and	SINDEX,0x08,SCBARRAY+1
 	and	A,WIDE_BUS,FLAGS	# Wide bus?	
 	or	SINDEX,A
@@ -252,8 +324,8 @@ start_scb:
 	or	SINDEX,0x80	call mk_mesg	# IDENTIFY message
 
 	mov	A,SINDEX
+	test	SCBARRAY+0,0xc0	jz  !message	# WDTR or SDTR??
 	cmp	MSG_START+0,A	jne !message	# did driver beat us?
-	test	FLAGS,CHECK_DTR jz !message	# Don't even bother with DTR?
 	mvi	MSG_START+1	call mk_dtr	# build DTR message if needed
 
 !message:
@@ -337,7 +409,7 @@ ITloop:
 	cmp	A,0xa0		je p_mesgout
 	cmp	A,0xe0		je p_mesgin
 
-	mvi	INTSTAT,SIGNAL_0		# unknown - signal driver
+	mvi	INTSTAT,BAD_PHASE		# unknown - signal driver
 
 p_dataout:
 	mvi	0		call scsisig	# !CDO|!IOO|!MSGO
@@ -544,8 +616,8 @@ p_mesgin:
 #  extra work in the kernel driver to ensure that the entry was removed 
 #  before the command complete code tried processing it.
 
-	test	SCBARRAY+14,0xff	jz status_ok  # 0 Status?
-	mvi	INTSTAT,STATUS_ERROR		# let driver know
+	test	SCBARRAY+14,0xff	jz status_ok	# 0 Status?
+	mvi	INTSTAT,BAD_STATUS			# let driver know
 	test	FLAGS,SENSE	jz status_ok
 	jmp	p_mesgin_done
 
@@ -585,12 +657,13 @@ p_mesgin1:
 p_mesginWDTR:
 	cmp	ARG_1,2		jne p_mesginN	# extended mesg length = 2
 	mvi	A		call inb_next	# Width of bus
-	mvi	INTSTAT,SIGNAL_WDTR		# let driver know
+	mvi	INTSTAT,MSG_WDTR		# let driver know
 	test	RETURN_1,0x80	jz p_mesgin_done# Do we need to send WDTR?
 
 # We didn't initiate the wide negotiation, so we must respond to the request
 	and	RETURN_1,0x7f			# Clear the SEND_WDTR Flag
 	or	FLAGS,ACTIVE_MSG
+	mvi	DINDEX,MSG_START+0
 	mvi	MSG_START+0	call mk_wdtr	# build WDTR message	
 	or	SINDEX,0x10,SIGSTATE		# turn on ATNO
 	call	scsisig
@@ -600,11 +673,12 @@ p_mesginSDTR:
 	cmp	ARG_1,3		jne p_mesginN	# extended mesg length = 3
 	mvi	ARG_1		call inb_next	# xfer period
 	mvi	A		call inb_next	# REQ/ACK offset
-	mvi	INTSTAT,SIGNAL_4		# call driver to convert
+	mvi	INTSTAT,MSG_SDTR		# call driver to convert
 
 	test	RETURN_1,0x80	jz p_mesgin_done# Do we need to mk_sdtr?
 
 	or	FLAGS,ACTIVE_MSG
+	mvi	DINDEX, MSG_START+0
 	mvi     MSG_START+0     call mk_sdtr
 	or	SINDEX,0x10,SIGSTATE		# turn on ATNO
 	call	scsisig
@@ -662,70 +736,15 @@ p_mesgin5:
 						#   required on reselect
 	jmp	p_mesgin_done
 
-#  Message reject?  If we have an outstanding WDTR or SDTR negotiation, assume
-#  that it's a response from the target selecting 8bit or asynchronous transfer,
-#  otherwise just ignore it since we have no clue what it pertains to.
-#
-#  XXX - I don't have a device that responds this way.  Does this code
-#	 actually work?
+#  Message reject?  Let the kernel driver handle this.  If we have an 
+#  outstanding WDTR or SDTR negotiation, assume that it's a response from 
+#  the target selecting 8bit or asynchronous transfer, otherwise just ignore 
+#  it since we have no clue what it pertains to.
 #
 p_mesgin6:
 	cmp	A,7		jne p_mesgin7	# message reject code?
 
-	and	FUNCTION1,0x70,SCSIID		# outstanding SDTR message?
-	mov	A,FUNCTION1
-	
-	test	SBLKCTL,0x08	jnz p_mesgin6_b	
-	test	SCSIID,0x80	jnz p_mesgin6_b	
-	test	NEEDWDTR_A,A	jnz clear_wdtr_a
-	test	NEEDSDTR_A,A	jnz clear_sdtr_a
-	jmp	p_mesgin_done  # no - ignore rejection
-
-clear_sdtr_a:
-	call	ndx_dtr				# note use of asynch xfer
-	mov	DINDEX,SINDEX
-	and	DINDIR,0x80,SINDIR
-
-	not	A
-	and	NEEDSDTR_A,A
-	jmp	clear_sdtr_done
-
-clear_wdtr_a:
-	call	ndx_dtr				# note use of 8bit xfer
-	mov	DINDEX,SINDEX
-	and	DINDIR,0x7f,SINDIR
-
-	not	A
-	and	NEEDWDTR_A,A
-	jmp	clear_wdtr_done
-
-p_mesgin6_b:
-	test	NEEDWDTR_B,A	jnz clear_wdtr_b
-	test	NEEDSDTR_B,A	jnz clear_sdtr_b
-	jmp	p_mesgin_done	# no - ignore rejection	
-
-clear_wdtr_b:
-	call	ndx_dtr				# note use of 8bit xfer
-	mov	DINDEX,SINDEX
-	and	DINDIR,0x7f,SINDIR
-
-	not	A
-	and	NEEDWDTR_B,A
-
-clear_wdtr_done:
-	and	SCSIRATE,0x7f			# select 8bit xfer
-	jmp	p_mesgin_done
-
-clear_sdtr_b:
-	call	ndx_dtr				# note use of asynch xfer
-	mov	DINDEX,SINDEX
-	and	DINDIR,0x80,SINDIR
-
-	not	A
-	and	NEEDSDTR_B,A
-	
-clear_sdtr_done:
-	and	SCSIRATE,0xf0			# select asynch xfer
+	mvi	INTSTAT, MSG_REJECT
 	jmp	p_mesgin_done
 
 #  [ ADD MORE MESSAGE HANDLING HERE ]
@@ -742,7 +761,7 @@ p_mesgin7:
 p_mesginN:
 	or	SINDEX,0x10,SIGSTATE		# turn on ATNO
 	call	scsisig
-	mvi	INTSTAT,SIGNAL_1		# let driver know
+	mvi	INTSTAT,SEND_REJECT		# let driver know
 
 	mvi	0x7		call mk_mesg	# MESSAGE REJECT message
 
@@ -964,7 +983,7 @@ assert:
 	test	FLAGS,RESELECTED	jz assert1	# reselected?
 	test	FLAGS,IDENTIFY_SEEN	jnz assert1	# seen IDENTIFY?
 
-	mvi	INTSTAT,SIGNAL_2		# no - cause a kernel panic
+	mvi	INTSTAT,NO_IDENT		# no - cause a kernel panic
 
 assert1:
 	ret
@@ -1019,7 +1038,7 @@ findSCB2:
 	mov	A,SCBCOUNT
 	cmp	SINDEX,A	jne findSCB1
 
-	mvi	INTSTAT,SIGNAL_3		# not found - signal kernel
+	mvi	INTSTAT,NO_MATCH		# not found - signal kernel
 	mvi	0x6		call mk_mesg	# ABORT message
 
 	or	SINDEX,0x10,SIGSTATE		# assert ATNO
@@ -1053,7 +1072,7 @@ sg_ram2scb:
 
 	and	SCBARRAY+0,0xef,SCBARRAY+0
 	test	SG_NOLOAD,0x80	jz sg_ram2scb1	# reload s/g?
-	or	SCBARRAY+0,0x10
+	or	SCBARRAY+0,SG_LOAD
 
 sg_ram2scb1:
 	ret
@@ -1112,10 +1131,16 @@ sg_load2:
 	mov	SCBARRAY+21,DFDAT
 	mov	SCBARRAY+22,DFDAT
 
+# For Linux, we must throw away four bytes since there is a 32bit gap
+# in the middle of a struct scatterlist
+#	mov	NONE,DFDAT
+#	mov	NONE,DFDAT
+#	mov	NONE,DFDAT
+#	mov	NONE,DFDAT
+
 	mov	SCBARRAY+23,DFDAT
 	mov	SCBARRAY+24,DFDAT
-	mov	SCBARRAY+25,DFDAT
-	mov	NONE,DFDAT			#Only support 24 bit length.
+	mov	SCBARRAY+25,DFDAT		#Only support 24 bit length.
 
 sg_load3:
 	ret
@@ -1173,19 +1198,11 @@ ndx_dtr_2:
 mk_dtr:
 	mov	DINDEX,SINDEX			# save SINDEX
 
-	call	ndx_dtr
-	test	SCBARRAY+1,0x88	jz  mk_dtr_a
-	test	NEEDWDTR_B,A	jnz mk_wdtr_16	# do we need negotiation?
-	test	NEEDSDTR_B,A	jnz mk_sdtr
-	ret
-mk_dtr_a:
-	test	NEEDWDTR_A,A	jnz mk_wdtr_16	# do we need negotiation?
-	test	NEEDSDTR_A,A	jnz mk_sdtr
-	ret
-
-mk_wdtr_16:
-	mvi	ARG_1,1			# 16bit wide bus
+	test	SCBARRAY+0,NEEDWDTR jnz  mk_wdtr_16bit
+	jmp	mk_sdtr
 
+mk_wdtr_16bit:
+	mvi	ARG_1,BUS_16_BIT
 mk_wdtr:
 	mvi	DINDIR,1			# extended message
 	mvi	DINDIR,2			# extended message length = 2