aic7xxx.seq revision 5326
14866Sgibbs# @(#)aic7xxx.seq 1.31 94/11/25 jda 24568Sgibbs# 34568Sgibbs# Adaptec 274x device driver for Linux. 44568Sgibbs# Copyright (c) 1994 The University of Calgary Department of Computer Science. 54568Sgibbs# 64568Sgibbs# This program is free software; you can redistribute it and/or modify 74568Sgibbs# it under the terms of the GNU General Public License as published by 84568Sgibbs# the Free Software Foundation; either version 2 of the License, or 94568Sgibbs# (at your option) any later version. 104568Sgibbs# 114568Sgibbs# This program is distributed in the hope that it will be useful, 124568Sgibbs# but WITHOUT ANY WARRANTY; without even the implied warranty of 134568Sgibbs# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 144568Sgibbs# GNU General Public License for more details. 154568Sgibbs# 164568Sgibbs# You should have received a copy of the GNU General Public License 174568Sgibbs# along with this program; if not, write to the Free Software 184568Sgibbs# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 194568Sgibbs 204866SgibbsVERSION AIC7XXX_SEQ_VERSION 1.31 214568Sgibbs 224866SgibbsSCBMASK = 0x1f 234568Sgibbs 244568SgibbsSCSISEQ = 0x00 254568SgibbsSXFRCTL0 = 0x01 264568SgibbsSXFRCTL1 = 0x02 274568SgibbsSCSISIGI = 0x03 284568SgibbsSCSISIGO = 0x03 294568SgibbsSCSIRATE = 0x04 304568SgibbsSCSIID = 0x05 314568SgibbsSCSIDATL = 0x06 324568SgibbsSTCNT = 0x08 334568SgibbsSTCNT+0 = 0x08 344568SgibbsSTCNT+1 = 0x09 354568SgibbsSTCNT+2 = 0x0a 364568SgibbsSSTAT0 = 0x0b 374568SgibbsCLRSINT1 = 0x0c 384568SgibbsSSTAT1 = 0x0c 394568SgibbsSIMODE1 = 0x11 404568SgibbsSCSIBUSL = 0x12 414568SgibbsSHADDR = 0x14 424568SgibbsSELID = 0x19 434568SgibbsSBLKCTL = 0x1f 444568SgibbsSEQCTL = 0x60 454568SgibbsA = 0x64 # == ACCUM 464568SgibbsSINDEX = 0x65 474568SgibbsDINDEX = 0x66 484568SgibbsALLZEROS = 0x6a 494568SgibbsNONE = 0x6a 504568SgibbsSINDIR = 0x6c 514568SgibbsDINDIR = 0x6d 524568SgibbsFUNCTION1 = 0x6e 534568SgibbsHADDR = 0x88 544568SgibbsHCNT = 0x8c 554568SgibbsHCNT+0 = 0x8c 564568SgibbsHCNT+1 = 0x8d 574568SgibbsHCNT+2 = 0x8e 584568SgibbsSCBPTR = 0x90 594568SgibbsINTSTAT = 0x91 604568SgibbsDFCNTRL = 0x93 614568SgibbsDFSTATUS = 0x94 624568SgibbsDFDAT = 0x99 634568SgibbsQINFIFO = 0x9b 644568SgibbsQINCNT = 0x9c 654568SgibbsQOUTFIFO = 0x9d 664568Sgibbs 675326SgibbsSCSICONF_A = 0x5a 685326SgibbsSCSICONF_B = 0x5b 694568Sgibbs 704568Sgibbs# The two reserved bytes at SCBARRAY+1[23] are expected to be set to 714568Sgibbs# zero, and the reserved bit in SCBARRAY+0 is used as an internal flag 724568Sgibbs# to indicate whether or not to reload scatter-gather parameters after 734568Sgibbs# a disconnect. 744568Sgibbs# 754568SgibbsSCBARRAY+0 = 0xa0 764568SgibbsSCBARRAY+1 = 0xa1 774568SgibbsSCBARRAY+2 = 0xa2 784568SgibbsSCBARRAY+3 = 0xa3 794568SgibbsSCBARRAY+7 = 0xa7 804568SgibbsSCBARRAY+11 = 0xab 814568SgibbsSCBARRAY+14 = 0xae 824568SgibbsSCBARRAY+15 = 0xaf 834568SgibbsSCBARRAY+16 = 0xb0 844568SgibbsSCBARRAY+17 = 0xb1 854568SgibbsSCBARRAY+18 = 0xb2 864568SgibbsSCBARRAY+19 = 0xb3 874568SgibbsSCBARRAY+20 = 0xb4 884568SgibbsSCBARRAY+21 = 0xb5 894568SgibbsSCBARRAY+22 = 0xb6 904568SgibbsSCBARRAY+23 = 0xb7 914568SgibbsSCBARRAY+24 = 0xb8 924568SgibbsSCBARRAY+25 = 0xb9 934568Sgibbs 944568SgibbsSIGNAL_0 = 0x01 # unknown scsi bus phase 954568SgibbsSIGNAL_1 = 0x11 # message reject 964568SgibbsSIGNAL_2 = 0x21 # no IDENTIFY after reconnect 974568SgibbsSIGNAL_3 = 0x31 # no cmd match for reconnect 984568SgibbsSIGNAL_4 = 0x41 # SDTR -> SCSIRATE conversion 994568SgibbsSTATUS_ERROR = 0x51 1004568Sgibbs 1014568Sgibbs# The host adapter card (at least the BIOS) uses 20-2f for SCSI 1025326Sgibbs# device information, 32-33 and 5a-5f as well. As it turns out, the 1035326Sgibbs# BIOS trashes 20-2f, writing the synchronous negotiation results 1044568Sgibbs# on top of the BIOS values, so we re-use those for our per-target 1054568Sgibbs# scratchspace (actually a value that can be copied directly into 1065326Sgibbs# SCSIRATE). The kernel driver will enable synchronous negotiation 1075326Sgibbs# for all targets that have a value other than 0 in the lower four 1085326Sgibbs# bits of the target scratch space. This should work irregardless of 1095326Sgibbs# whether the bios has been installed. NEEDSDTR has one bit per target 1105326Sgibbs# indicating if an SDTR message is needed for that device - this will 1115326Sgibbs# be set initially (based on a search through the target scratch space), 1125326Sgibbs# as well as after a bus reset condition. 1134568Sgibbs# 1144568Sgibbs# The high bit of DROPATN is set if ATN should be dropped before the ACK 1154568Sgibbs# when outb is called. REJBYTE contains the first byte of a MESSAGE IN 1164568Sgibbs# message, so the driver can report an intelligible error if a message is 1174568Sgibbs# rejected. 1184568Sgibbs# 1194568Sgibbs# RESELECT's high bit is true if we are currently handling a reselect; 1204568Sgibbs# its next-highest bit is true ONLY IF we've seen an IDENTIFY message 1214568Sgibbs# from the reselecting target. If we haven't had IDENTIFY, then we have 1224568Sgibbs# no idea what the lun is, and we can't select the right SCB register 1234568Sgibbs# bank, so force a kernel panic if the target attempts a data in/out or 1244568Sgibbs# command phase instead of corrupting something. 1254568Sgibbs# 1264568Sgibbs# Note that SG_NEXT occupies four bytes. 1274568Sgibbs# 1284568SgibbsSYNCNEG = 0x20 1294568Sgibbs 1304568SgibbsDROPATN = 0x30 1314568SgibbsREJBYTE = 0x31 1325326SgibbsDISC_DSB_A = 0x32 1335326SgibbsDISC_DSB_B = 0x33 1344568SgibbsRESELECT = 0x34 1354568Sgibbs 1364568SgibbsMSG_FLAGS = 0x35 1374568SgibbsMSG_LEN = 0x36 1384568SgibbsMSG_START+0 = 0x37 1394568SgibbsMSG_START+1 = 0x38 1404568SgibbsMSG_START+2 = 0x39 1414568SgibbsMSG_START+3 = 0x3a 1424568SgibbsMSG_START+4 = 0x3b 1434568SgibbsMSG_START+5 = 0x3c 1444568Sgibbs-MSG_START+0 = 0xc9 # 2's complement of MSG_START+0 1454568Sgibbs 1464568SgibbsARG_1 = 0x4c # sdtr conversion args & return 1474568SgibbsRETURN_1 = 0x4c 1484568Sgibbs 1495326SgibbsSIGSTATE = 0x4d # value written to SCSISIGO 1505326SgibbsNEEDSDTR_A = 0x4e # send SDTR message, 1 bit/trgt 1515326SgibbsNEEDSDTR_B = 0x4f 1524568Sgibbs 1534568SgibbsSG_SIZEOF = 0x8 # sizeof(struct scatterlist) 1544568SgibbsSG_NOLOAD = 0x50 # load SG pointer/length? 1554568SgibbsSG_COUNT = 0x51 # working value of SG count 1564568SgibbsSG_NEXT = 0x52 # working value of SG pointer 1574568SgibbsSG_NEXT+0 = 0x52 1584568SgibbsSG_NEXT+1 = 0x53 1594568SgibbsSG_NEXT+2 = 0x54 1604568SgibbsSG_NEXT+3 = 0x55 1614568Sgibbs 1624568SgibbsSCBCOUNT = 0x56 # the actual number of SCBs 1635326SgibbsFLAGS = 0x57 # Device configuration flags 1645326SgibbsTWIN_BUS = 0x01 1655326SgibbsWIDE_BUS = 0x02 1664568Sgibbs 1675326SgibbsACTIVE_A = 0x58 1685326SgibbsACTIVE_B = 0x59 1695326Sgibbs 1704866Sgibbs# Poll QINCNT for work - the lower bits contain 1714568Sgibbs# the number of entries in the Queue In FIFO. 1724568Sgibbs# 1734568Sgibbsstart: 1745326Sgibbs test FLAGS,TWIN_BUS jz start2 # Are we a twin channel device? 1755326Sgibbs# For fairness, we check the other bus first, since we just finished a 1765326Sgibbs# transaction on the current channel. 1775326Sgibbs xor SBLKCTL,0x08 # Toggle to the other bus 1784568Sgibbs test SCSISIGI,0x4 jnz reselect # BSYI 1795326Sgibbs xor SBLKCTL,0x08 # Toggle to the original bus 1805326Sgibbsstart2: 1815326Sgibbs test SCSISIGI,0x4 jnz reselect # BSYI 1824866Sgibbs test QINCNT,SCBMASK jz start 1834568Sgibbs 1844568Sgibbs# We have at least one queued SCB now. Set the SCB pointer 1854568Sgibbs# from the FIFO so we see the right bank of SCB registers, 1864568Sgibbs# then set SCSI options and set the initiator and target 1874568Sgibbs# SCSI IDs. 1884568Sgibbs# 1894568Sgibbs mov SCBPTR,QINFIFO 1904568Sgibbs 1914568Sgibbs# See if there is not already an active SCB for this target. This code 1925326Sgibbs# locks out on a per target basis instead of target/lun. Although this 1935326Sgibbs# is not ideal for devices that have multiple luns active at the same 1945326Sgibbs# time, it is faster than looping through all SCB's looking for active 1955326Sgibbs# commands. It may be benificial to make findscb a more general procedure 1965326Sgibbs# to see if the added cost of the search is negligible. This code also 1975326Sgibbs# assumes that the kernel driver will clear the active flags on board 1985326Sgibbs# initialization, board reset, and a target's SELTO. 1994568Sgibbs 2004568Sgibbs and FUNCTION1,0x70,SCBARRAY+1 2014568Sgibbs mov A,FUNCTION1 2025326Sgibbs test SCBARRAY+1,0x88 jz test_a # Id < 8 && A channel 2035326Sgibbs 2045326Sgibbs test ACTIVE_B,A jnz requeue 2055326Sgibbs or ACTIVE_B,A # Mark the current target as busy 2065326Sgibbs jmp start_scb 2075326Sgibbs 2084568Sgibbs# Place the currently active back on the queue for later processing 2095326Sgibbsrequeue: 2104568Sgibbs mov QINFIFO, SCBPTR 2114568Sgibbs jmp start 2124568Sgibbs 2135326Sgibbstest_a: 2145326Sgibbs test ACTIVE_A,A jnz requeue 2155326Sgibbs or ACTIVE_A,A # Mark the current target as busy 2165326Sgibbs 2175326Sgibbsstart_scb: 2185326Sgibbs and A,0x08,SCBARRAY+1 2195326Sgibbs mov SBLKCTL,A # select channel, !wide 2204568Sgibbs mov SCBARRAY+1 call initialize 2214568Sgibbs clr SG_NOLOAD 2224568Sgibbs clr RESELECT 2234568Sgibbs 2244568Sgibbs# As soon as we get a successful selection, the target should go 2254568Sgibbs# into the message out phase since we have ATN asserted. Prepare 2264568Sgibbs# the message to send, locking out the device driver. If the device 2274568Sgibbs# driver hasn't beaten us with an ABORT or RESET message, then tack 2284866Sgibbs# on an SDTR negotiation if required. 2294568Sgibbs# 2304568Sgibbs# Messages are stored in scratch RAM starting with a flag byte (high bit 2314568Sgibbs# set means active message), one length byte, and then the message itself. 2324568Sgibbs# 2334568Sgibbs mov SCBARRAY+1 call disconnect # disconnect ok? 2344568Sgibbs 2354568Sgibbs and SINDEX,0x7,SCBARRAY+1 # lun 2364568Sgibbs or SINDEX,A # return value from disconnect 2374568Sgibbs or SINDEX,0x80 call mk_mesg # IDENTIFY message 2384568Sgibbs 2394568Sgibbs mov A,SINDEX 2404568Sgibbs cmp MSG_START+0,A jne !message # did driver beat us? 2414568Sgibbs mvi MSG_START+1 call mk_sdtr # build SDTR message if needed 2424568Sgibbs 2434568Sgibbs!message: 2444568Sgibbs 2454568Sgibbs# Enable selection phase as an initiator, and do automatic ATN 2464568Sgibbs# after the selection. 2474568Sgibbs# 2484568Sgibbs mvi SCSISEQ,0x48 # ENSELO|ENAUTOATNO 2494568Sgibbs 2504568Sgibbs# Wait for successful arbitration. The AIC-7770 documentation says 2514568Sgibbs# that SELINGO indicates successful arbitration, and that it should 2524568Sgibbs# be used to look for SELDO. However, if the sequencer is paused at 2534568Sgibbs# just the right time - a parallel fsck(8) on two drives did it for 2544568Sgibbs# me - then SELINGO can flip back to false before we've seen it. This 2554568Sgibbs# makes the sequencer sit in the arbitration loop forever. This is 2564568Sgibbs# Not Good. 2574568Sgibbs# 2584568Sgibbs# Therefore, I've added a check in the arbitration loop for SELDO 2594568Sgibbs# too. This could arguably be made a critical section by disabling 2604568Sgibbs# pauses, but I don't want to make a potentially infinite loop a CS. 2614568Sgibbs# I suppose you could fold it into the select loop, too, but since 2624568Sgibbs# I've been hunting this bug for four days it's kinda like a trophy. 2634568Sgibbs# 2644568Sgibbsarbitrate: 2654568Sgibbs test SSTAT0,0x40 jnz *select # SELDO 2664568Sgibbs test SSTAT0,0x10 jz arbitrate # SELINGO 2674568Sgibbs 2684568Sgibbs# Wait for a successful selection. If the hardware selection 2694568Sgibbs# timer goes off, then the driver gets the interrupt, so we don't 2704568Sgibbs# need to worry about it. 2714568Sgibbs# 2724568Sgibbsselect: 2734568Sgibbs test SSTAT0,0x40 jz select # SELDO 2744568Sgibbs jmp *select 2754568Sgibbs 2764568Sgibbs# Reselection is being initiated by a target - we've seen the BSY 2774568Sgibbs# line driven active, and we didn't do it! Enable the reselection 2784568Sgibbs# hardware, and wait for it to finish. Make a note that we've been 2794568Sgibbs# reselected, but haven't seen an IDENTIFY message from the target 2804568Sgibbs# yet. 2814568Sgibbs# 2824568Sgibbsreselect: 2834568Sgibbs mvi SCSISEQ,0x10 # ENRSELI 2844568Sgibbs 2854568Sgibbsreselect1: 2864568Sgibbs test SSTAT0,0x20 jz reselect1 # SELDI 2874568Sgibbs mov SELID call initialize 2884568Sgibbs 2894568Sgibbs mvi RESELECT,0x80 # reselected, no IDENTIFY 2904568Sgibbs 2914568Sgibbs# After the [re]selection, make sure that the [re]selection enable 2924568Sgibbs# bit is off. This chip is flaky enough without extra things 2934568Sgibbs# turned on. Also clear the BUSFREE bit in SSTAT1 since we'll be 2944568Sgibbs# using it shortly. 2954568Sgibbs# 2964568Sgibbs*select: 2974568Sgibbs clr SCSISEQ 2984568Sgibbs mvi CLRSINT1,0x8 # CLRBUSFREE 2994568Sgibbs 3004568Sgibbs# Main loop for information transfer phases. If BSY is false, then 3014568Sgibbs# we have a bus free condition, expected or not. Otherwise, wait 3024568Sgibbs# for the target to assert REQ before checking MSG, C/D and I/O 3034568Sgibbs# for the bus phase. 3044568Sgibbs# 3054568Sgibbs# We can't simply look at the values of SCSISIGI here (if we want 3064568Sgibbs# to do synchronous data transfer), because the target won't assert 3074568Sgibbs# REQ if it's already sent us some data that we haven't acknowledged 3084568Sgibbs# yet. 3094568Sgibbs# 3104568SgibbsITloop: 3114568Sgibbs test SSTAT1,0x8 jnz p_busfree # BUSFREE 3124568Sgibbs test SSTAT1,0x1 jz ITloop # REQINIT 3134568Sgibbs 3144568Sgibbs and A,0xe0,SCSISIGI # CDI|IOI|MSGI 3154568Sgibbs 3164568Sgibbs cmp ALLZEROS,A je p_dataout 3174568Sgibbs cmp A,0x40 je p_datain 3184568Sgibbs cmp A,0x80 je p_command 3194568Sgibbs cmp A,0xc0 je p_status 3204568Sgibbs cmp A,0xa0 je p_mesgout 3214568Sgibbs cmp A,0xe0 je p_mesgin 3224568Sgibbs 3234568Sgibbs mvi INTSTAT,SIGNAL_0 # unknown - signal driver 3244568Sgibbs 3254568Sgibbsp_dataout: 3264568Sgibbs mvi 0 call scsisig # !CDO|!IOO|!MSGO 3274568Sgibbs call assert 3284568Sgibbs call sg_load 3294568Sgibbs 3304568Sgibbs mvi A,3 3314568Sgibbs mvi DINDEX,HCNT 3324568Sgibbs mvi SCBARRAY+23 call bcopy 3334568Sgibbs 3344568Sgibbs mvi A,3 3354568Sgibbs mvi DINDEX,STCNT 3364568Sgibbs mvi SCBARRAY+23 call bcopy 3374568Sgibbs 3384568Sgibbs mvi A,4 3394568Sgibbs mvi DINDEX,HADDR 3404568Sgibbs mvi SCBARRAY+19 call bcopy 3414568Sgibbs 3424568Sgibbs mvi 0x3d call dma # SCSIEN|SDMAEN|HDMAEN| 3434568Sgibbs # DIRECTION|FIFORESET 3444568Sgibbs 3454568Sgibbs# After a DMA finishes, save the final transfer pointer and count 3464568Sgibbs# back into the SCB, in case a device disconnects in the middle of 3474568Sgibbs# a transfer. Use SHADDR and STCNT instead of HADDR and HCNT, since 3484568Sgibbs# it's a reflection of how many bytes were transferred on the SCSI 3494568Sgibbs# (as opposed to the host) bus. 3504568Sgibbs# 3514568Sgibbs mvi A,3 3524568Sgibbs mvi DINDEX,SCBARRAY+23 3534568Sgibbs mvi STCNT call bcopy 3544568Sgibbs 3554568Sgibbs mvi A,4 3564568Sgibbs mvi DINDEX,SCBARRAY+19 3574568Sgibbs mvi SHADDR call bcopy 3584568Sgibbs 3594568Sgibbs call sg_advance 3604568Sgibbs mov SCBARRAY+18,SG_COUNT # residual S/G count 3614568Sgibbs 3624568Sgibbs jmp ITloop 3634568Sgibbs 3644568Sgibbsp_datain: 3654568Sgibbs mvi 0x40 call scsisig # !CDO|IOO|!MSGO 3664568Sgibbs call assert 3674568Sgibbs call sg_load 3684568Sgibbs 3694568Sgibbs mvi A,3 3704568Sgibbs mvi DINDEX,HCNT 3714568Sgibbs mvi SCBARRAY+23 call bcopy 3724568Sgibbs 3734568Sgibbs mvi A,3 3744568Sgibbs mvi DINDEX,STCNT 3754568Sgibbs mvi SCBARRAY+23 call bcopy 3764568Sgibbs 3774568Sgibbs mvi A,4 3784568Sgibbs mvi DINDEX,HADDR 3794568Sgibbs mvi SCBARRAY+19 call bcopy 3804568Sgibbs 3814568Sgibbs mvi 0x39 call dma # SCSIEN|SDMAEN|HDMAEN| 3824568Sgibbs # !DIRECTION|FIFORESET 3834568Sgibbs mvi A,3 3844568Sgibbs mvi DINDEX,SCBARRAY+23 3854568Sgibbs mvi STCNT call bcopy 3864568Sgibbs 3874568Sgibbs mvi A,4 3884568Sgibbs mvi DINDEX,SCBARRAY+19 3894568Sgibbs mvi SHADDR call bcopy 3904568Sgibbs 3914568Sgibbs call sg_advance 3924568Sgibbs mov SCBARRAY+18,SG_COUNT # residual S/G count 3934568Sgibbs 3944568Sgibbs jmp ITloop 3954568Sgibbs 3964568Sgibbs# Command phase. Set up the DMA registers and let 'er rip - the 3974568Sgibbs# two bytes after the SCB SCSI_cmd_length are zeroed by the driver, 3984568Sgibbs# so we can copy those three bytes directly into HCNT. 3994568Sgibbs# 4004568Sgibbsp_command: 4014568Sgibbs mvi 0x80 call scsisig # CDO|!IOO|!MSGO 4024568Sgibbs call assert 4034568Sgibbs 4044568Sgibbs mvi A,3 4054568Sgibbs mvi DINDEX,HCNT 4064568Sgibbs mvi SCBARRAY+11 call bcopy 4074568Sgibbs 4084568Sgibbs mvi A,3 4094568Sgibbs mvi DINDEX,STCNT 4104568Sgibbs mvi SCBARRAY+11 call bcopy 4114568Sgibbs 4124568Sgibbs mvi A,4 4134568Sgibbs mvi DINDEX,HADDR 4144568Sgibbs mvi SCBARRAY+7 call bcopy 4154568Sgibbs 4164568Sgibbs mvi 0x3d call dma # SCSIEN|SDMAEN|HDMAEN| 4174568Sgibbs # DIRECTION|FIFORESET 4184568Sgibbs jmp ITloop 4194568Sgibbs 4204568Sgibbs# Status phase. Wait for the data byte to appear, then read it 4214568Sgibbs# and store it into the SCB. 4224568Sgibbs# 4234568Sgibbsp_status: 4244568Sgibbs mvi 0xc0 call scsisig # CDO|IOO|!MSGO 4254568Sgibbs 4264568Sgibbs mvi SCBARRAY+14 call inb 4274568Sgibbs jmp ITloop 4284568Sgibbs 4294568Sgibbs# Message out phase. If there is no active message, but the target 4304568Sgibbs# took us into this phase anyway, build a no-op message and send it. 4314568Sgibbs# 4324568Sgibbsp_mesgout: 4334568Sgibbs mvi 0xa0 call scsisig # CDO|!IOO|MSGO 4344568Sgibbs mvi 0x8 call mk_mesg # build NOP message 4354568Sgibbs 4364568Sgibbs# Set up automatic PIO transfer from MSG_START. Bit 3 in 4374568Sgibbs# SXFRCTL0 (SPIOEN) is already on. 4384568Sgibbs# 4394568Sgibbs mvi SINDEX,MSG_START+0 4404568Sgibbs mov DINDEX,MSG_LEN 4414568Sgibbs clr A 4424568Sgibbs 4434568Sgibbs# When target asks for a byte, drop ATN if it's the last one in 4444568Sgibbs# the message. Otherwise, keep going until the message is exhausted. 4454568Sgibbs# (We can't use outb for this since it wants the input in SINDEX.) 4464568Sgibbs# 4474568Sgibbs# Keep an eye out for a phase change, in case the target issues 4484568Sgibbs# a MESSAGE REJECT. 4494568Sgibbs# 4504568Sgibbsp_mesgout2: 4514568Sgibbs test SSTAT0,0x2 jz p_mesgout2 # SPIORDY 4524568Sgibbs test SSTAT1,0x10 jnz p_mesgout6 # PHASEMIS 4534568Sgibbs 4544568Sgibbs cmp DINDEX,1 jne p_mesgout3 # last byte? 4554568Sgibbs mvi CLRSINT1,0x40 # CLRATNO - drop ATN 4564568Sgibbs 4574568Sgibbs# Write a byte to the SCSI bus. The AIC-7770 refuses to automatically 4584568Sgibbs# send ACKs in automatic PIO or DMA mode unless you make sure that the 4594568Sgibbs# "expected" bus phase in SCSISIGO matches the actual bus phase. This 4604568Sgibbs# behaviour is completely undocumented and caused me several days of 4614568Sgibbs# grief. 4624568Sgibbs# 4634568Sgibbs# After plugging in different drives to test with and using a longer 4644568Sgibbs# SCSI cable, I found that I/O in Automatic PIO mode ceased to function, 4654568Sgibbs# especially when transferring >1 byte. It seems to be much more stable 4664568Sgibbs# if STCNT is set to one before the transfer, and SDONE (in SSTAT0) is 4674568Sgibbs# polled for transfer completion - for both output _and_ input. The 4684568Sgibbs# only theory I have is that SPIORDY doesn't drop right away when SCSIDATL 4694568Sgibbs# is accessed (like the documentation says it does), and that on a longer 4704568Sgibbs# cable run, the sequencer code was fast enough to loop back and see 4714568Sgibbs# an SPIORDY that hadn't dropped yet. 4724568Sgibbs# 4734568Sgibbsp_mesgout3: 4744568Sgibbs call one_stcnt 4754568Sgibbs mov SCSIDATL,SINDIR 4764568Sgibbs 4774568Sgibbsp_mesgout4: 4784568Sgibbs test SSTAT0,0x4 jz p_mesgout4 # SDONE 4794568Sgibbs dec DINDEX 4804568Sgibbs inc A 4814568Sgibbs cmp MSG_LEN,A jne p_mesgout2 4824568Sgibbs 4834568Sgibbs# If the next bus phase after ATN drops is a message out, it means 4844568Sgibbs# that the target is requesting that the last message(s) be resent. 4854568Sgibbs# 4864568Sgibbsp_mesgout5: 4874568Sgibbs test SSTAT1,0x8 jnz p_mesgout6 # BUSFREE 4884568Sgibbs test SSTAT1,0x1 jz p_mesgout5 # REQINIT 4894568Sgibbs 4904568Sgibbs and A,0xe0,SCSISIGI # CDI|IOI|MSGI 4914568Sgibbs cmp A,0xa0 jne p_mesgout6 4924568Sgibbs mvi 0x10 call scsisig # ATNO - re-assert ATN 4934568Sgibbs 4944568Sgibbs jmp ITloop 4954568Sgibbs 4964568Sgibbsp_mesgout6: 4974568Sgibbs mvi CLRSINT1,0x40 # CLRATNO - in case of PHASEMIS 4984568Sgibbs clr MSG_FLAGS # no active msg 4994568Sgibbs jmp ITloop 5004568Sgibbs 5014568Sgibbs# Message in phase. Bytes are read using Automatic PIO mode, but not 5024568Sgibbs# using inb. This alleviates a race condition, namely that if ATN had 5034568Sgibbs# to be asserted under Automatic PIO mode, it had to beat the SCSI 5044568Sgibbs# circuitry sending an ACK to the target. This showed up under heavy 5054568Sgibbs# loads and really confused things, since ABORT commands wouldn't be 5064568Sgibbs# seen by the drive after an IDENTIFY message in until it had changed 5074568Sgibbs# to a data I/O phase. 5084568Sgibbs# 5094568Sgibbsp_mesgin: 5104568Sgibbs mvi 0xe0 call scsisig # CDO|IOO|MSGO 5114568Sgibbs mvi A call inb_first # read the 1st message byte 5124568Sgibbs mvi REJBYTE,A # save it for the driver 5134568Sgibbs 5144568Sgibbs cmp ALLZEROS,A jne p_mesgin1 5154568Sgibbs 5164568Sgibbs# We got a "command complete" message, so put the SCB pointer 5174568Sgibbs# into the Queue Out, and trigger a completion interrupt. 5184568Sgibbs# Check status for non zero return and interrupt driver if needed 5195326Sgibbs# This allows the driver to interpret errors only when they occur 5205326Sgibbs# instead of always uploading the scb. If the status is SCSI_CHECK, 5215326Sgibbs# the driver will download a new scb requesting sense, to replace 5225326Sgibbs# the old one and the sequencer code will imediately jump to start 5235326Sgibbs# working on it. If the kernel driver does not wish to request sense, 5245326Sgibbs# the sequencer program counter is incremented by 1, preventing another run 5255326Sgibbs# on the current SCB and the command is allowed to complete. We don't 5265326Sgibbs# bother to post to the QOUTFIFO in the error case since it would require 5275326Sgibbs# extra work in the kernel driver to ensure that the entry was removed 5285326Sgibbs# before the command complete code tried processing it. 5294568Sgibbs 5304568Sgibbs test SCBARRAY+14,0xff jz status_ok # 0 Status? 5314568Sgibbs call inb_last # ack & turn auto PIO back on 5324568Sgibbs mvi INTSTAT,STATUS_ERROR # let driver know 5335326Sgibbs jmp start_scb 5345326Sgibbs 5354568Sgibbsstatus_ok: 5365326Sgibbs 5375326Sgibbs# First, mark this target as free. 5385326Sgibbs and FUNCTION1,0x70,SCBARRAY+1 5395326Sgibbs mov A,FUNCTION1 5405326Sgibbs test SCBARRAY+1,0x88 jz clear_a 5415326Sgibbs xor ACTIVE_B,A 5425326Sgibbs jmp complete 5435326Sgibbs 5445326Sgibbsclear_a: 5455326Sgibbs xor ACTIVE_A,A 5465326Sgibbs 5475326Sgibbscomplete: 5484568Sgibbs mov QOUTFIFO,SCBPTR 5495326Sgibbs mvi INTSTAT,0x02 # CMDCMPLT 5504568Sgibbs jmp p_mesgin_done 5514568Sgibbs 5524568Sgibbs# Is it an extended message? We only support the synchronous data 5534568Sgibbs# transfer request message, which will probably be in response to 5544568Sgibbs# an SDTR message out from us. If it's not an SDTR, reject it - 5554568Sgibbs# apparently this can be done after any message in byte, according 5564568Sgibbs# to the SCSI-2 spec. 5574568Sgibbs# 5584568Sgibbs# XXX - we should really reject this if we didn't initiate the SDTR 5594568Sgibbs# negotiation; this may cause problems with unusual devices. 5604568Sgibbs# 5614568Sgibbsp_mesgin1: 5624568Sgibbs cmp A,1 jne p_mesgin2 # extended message code? 5634568Sgibbs 5644568Sgibbs mvi A call inb_next 5654568Sgibbs cmp A,3 jne p_mesginN # extended mesg length = 3 5664568Sgibbs mvi A call inb_next 5674568Sgibbs cmp A,1 jne p_mesginN # SDTR code 5684568Sgibbs 5694568Sgibbs mvi ARG_1 call inb_next # xfer period 5705326Sgibbs mvi A call inb_next # REQ/ACK offset 5714568Sgibbs mvi INTSTAT,SIGNAL_4 # call driver to convert 5724568Sgibbs 5734568Sgibbs call ndx_sdtr # index sync config for target 5744568Sgibbs mov DINDEX,SINDEX 5755326Sgibbs not A # turn off "need sdtr" flag 5765326Sgibbs test SBLKCTL,0x08 jnz p_mesgin1_b 5775326Sgibbs test SCSIID,0x80 jnz p_mesgin1_b 5785326Sgibbs and NEEDSDTR_A,A 5795326Sgibbs jmp p_mesgin1_save 5805326Sgibbs 5815326Sgibbsp_mesgin1_b: 5825326Sgibbs and NEEDSDTR_B,A 5835326Sgibbs 5845326Sgibbsp_mesgin1_save: 5855326Sgibbs and A,0x80,SINDIR # get the WIDEXFER flag 5865326Sgibbs or RETURN_1,A # Set WIDEXFER if necessary 5874568Sgibbs mov DINDIR,RETURN_1 # save returned value 5884568Sgibbs 5894568Sgibbs# Even though the SCSI-2 specification says that a device responding 5904568Sgibbs# to our SDTR message should honor our parameters for transmitting 5914568Sgibbs# to us, it doesn't seem to work too well in real life. In particular, 5924568Sgibbs# a lot of CD-ROM and tape units don't function: try using the SDTR 5934568Sgibbs# parameters the device sent us for both transmitting and receiving. 5944568Sgibbs# 5954568Sgibbs mov SCSIRATE,RETURN_1 5964568Sgibbs jmp p_mesgin_done 5974568Sgibbs 5984568Sgibbs# Is it a disconnect message? Set a flag in the SCB to remind us 5994568Sgibbs# and await the bus going free. 6004568Sgibbs# 6014568Sgibbsp_mesgin2: 6024568Sgibbs cmp A,4 jne p_mesgin3 # disconnect code? 6034568Sgibbs 6044568Sgibbs or SCBARRAY+0,0x4 # set "disconnected" bit 6054568Sgibbs jmp p_mesgin_done 6064568Sgibbs 6074568Sgibbs# Save data pointers message? Copy working values into the SCB, 6084568Sgibbs# usually in preparation for a disconnect. 6094568Sgibbs# 6104568Sgibbsp_mesgin3: 6114568Sgibbs cmp A,2 jne p_mesgin4 # save data pointers code? 6124568Sgibbs 6134568Sgibbs call sg_ram2scb 6144568Sgibbs jmp p_mesgin_done 6154568Sgibbs 6164568Sgibbs# Restore pointers message? Data pointers are recopied from the 6174568Sgibbs# SCB anyway at the start of any DMA operation, so the only thing 6184568Sgibbs# to copy is the scatter-gather values. 6194568Sgibbs# 6204568Sgibbsp_mesgin4: 6214568Sgibbs cmp A,3 jne p_mesgin5 # restore pointers code? 6224568Sgibbs 6234568Sgibbs call sg_scb2ram 6244568Sgibbs jmp p_mesgin_done 6254568Sgibbs 6264568Sgibbs# Identify message? For a reconnecting target, this tells us the lun 6274568Sgibbs# that the reconnection is for - find the correct SCB and switch to it, 6284568Sgibbs# clearing the "disconnected" bit so we don't "find" it by accident later. 6294568Sgibbs# 6304568Sgibbsp_mesgin5: 6314568Sgibbs test A,0x80 jz p_mesgin6 # identify message? 6324568Sgibbs 6334568Sgibbs test A,0x78 jnz p_mesginN # !DiscPriv|!LUNTAR|!Reserved 6344568Sgibbs 6354568Sgibbs mov A call findSCB # switch to correct SCB 6364568Sgibbs 6374568Sgibbs# If a active message is present after calling findSCB, then either it 6384568Sgibbs# or the driver is trying to abort the command. Either way, something 6394568Sgibbs# untoward has happened and we should just leave it alone. 6404568Sgibbs# 6414568Sgibbs test MSG_FLAGS,0x80 jnz p_mesgin_done 6424568Sgibbs 6435326Sgibbs and SCBARRAY+0,0xfb # clear disconnect bit in SCB 6444568Sgibbs mvi RESELECT,0xc0 # make note of IDENTIFY 6454568Sgibbs 6464568Sgibbs call sg_scb2ram # implied restore pointers 6474568Sgibbs # required on reselect 6484568Sgibbs jmp p_mesgin_done 6494568Sgibbs 6504568Sgibbs# Message reject? If we have an outstanding SDTR negotiation, assume 6514568Sgibbs# that it's a response from the target selecting asynchronous transfer, 6524568Sgibbs# otherwise just ignore it since we have no clue what it pertains to. 6534568Sgibbs# 6544568Sgibbs# XXX - I don't have a device that responds this way. Does this code 6554568Sgibbs# actually work? 6564568Sgibbs# 6574568Sgibbsp_mesgin6: 6584568Sgibbs cmp A,7 jne p_mesgin7 # message reject code? 6594568Sgibbs 6604568Sgibbs and FUNCTION1,0x70,SCSIID # outstanding SDTR message? 6614568Sgibbs mov A,FUNCTION1 6625326Sgibbs 6635326Sgibbs test SBLKCTL,0x08 jnz p_mesgin6_b 6645326Sgibbs test SCSIID,0x80 jnz p_mesgin6_b 6655326Sgibbs test NEEDSDTR_A,A jz p_mesgin_done # no - ignore rejection 6665326Sgibbs call ndx_sdtr # note use of asynch xfer 6675326Sgibbs mov DINDEX,SINDEX 6685326Sgibbs clr DINDIR 6694568Sgibbs 6705326Sgibbs not A 6715326Sgibbs and NEEDSDTR_A,A 6725326Sgibbs jmp p_mesgin6_done 6735326Sgibbs 6745326Sgibbsp_mesgin6_b: 6755326Sgibbs test NEEDSDTR_B,A jz p_mesgin_done # no - ignore rejection 6764568Sgibbs call ndx_sdtr # note use of asynch xfer 6774568Sgibbs mov DINDEX,SINDEX 6784568Sgibbs clr DINDIR 6794568Sgibbs 6805326Sgibbs not A 6815326Sgibbs and NEEDSDTR_B,A 6825326Sgibbs 6835326Sgibbsp_mesgin6_done: 6844568Sgibbs 6854568Sgibbs clr SCSIRATE # select asynch xfer 6864568Sgibbs jmp p_mesgin_done 6874568Sgibbs 6884568Sgibbs# [ ADD MORE MESSAGE HANDLING HERE ] 6894568Sgibbs# 6904568Sgibbsp_mesgin7: 6914568Sgibbs 6924568Sgibbs# We have no idea what this message in is, and there's no way 6934568Sgibbs# to pass it up to the kernel, so we issue a message reject and 6944568Sgibbs# hope for the best. Since we're now using manual PIO mode to 6954568Sgibbs# read in the message, there should no longer be a race condition 6964568Sgibbs# present when we assert ATN. In any case, rejection should be a 6974568Sgibbs# rare occurrence - signal the driver when it happens. 6984568Sgibbs# 6994568Sgibbsp_mesginN: 7004568Sgibbs or SINDEX,0x10,SIGSTATE # turn on ATNO 7014568Sgibbs call scsisig 7024568Sgibbs mvi INTSTAT,SIGNAL_1 # let driver know 7034568Sgibbs 7044568Sgibbs mvi 0x7 call mk_mesg # MESSAGE REJECT message 7054568Sgibbs 7064568Sgibbsp_mesgin_done: 7074568Sgibbs call inb_last # ack & turn auto PIO back on 7084568Sgibbs jmp ITloop 7094568Sgibbs 7104568Sgibbs# Bus free phase. It might be useful to interrupt the device 7114568Sgibbs# driver if we aren't expecting this. For now, make sure that 7124568Sgibbs# ATN isn't being asserted and look for a new command. 7134568Sgibbs# 7144568Sgibbsp_busfree: 7154568Sgibbs mvi CLRSINT1,0x40 # CLRATNO 7164568Sgibbs clr SIGSTATE 7174568Sgibbs jmp start 7184568Sgibbs 7194568Sgibbs# Bcopy: number of bytes to transfer should be in A, DINDEX should 7204568Sgibbs# contain the destination address, and SINDEX should contain the 7214568Sgibbs# source address. All input parameters are trashed on return. 7224568Sgibbs# 7234568Sgibbsbcopy: 7244568Sgibbs mov DINDIR,SINDIR 7254568Sgibbs dec A 7264568Sgibbs cmp ALLZEROS,A jne bcopy 7274568Sgibbs ret 7284568Sgibbs 7294568Sgibbs# Locking the driver out, build a one-byte message passed in SINDEX 7304568Sgibbs# if there is no active message already. SINDEX is returned intact. 7314568Sgibbs# 7324568Sgibbsmk_mesg: 7334866Sgibbs mvi SEQCTL,0x50 # PAUSEDIS|FASTMODE 7344568Sgibbs test MSG_FLAGS,0x80 jnz mk_mesg1 # active message? 7354568Sgibbs 7364568Sgibbs mvi MSG_FLAGS,0x80 # if not, there is now 7374568Sgibbs mvi MSG_LEN,1 # length = 1 7384568Sgibbs mov MSG_START+0,SINDEX # 1-byte message 7394568Sgibbs 7404568Sgibbsmk_mesg1: 7414866Sgibbs mvi SEQCTL,0x10 # !PAUSEDIS|FASTMODE 7424568Sgibbs ret 7434568Sgibbs 7444568Sgibbs# Input byte in Automatic PIO mode. The address to store the byte 7454568Sgibbs# in should be in SINDEX. DINDEX will be used by this routine. 7464568Sgibbs# 7474568Sgibbsinb: 7484568Sgibbs test SSTAT0,0x2 jz inb # SPIORDY 7494568Sgibbs mov DINDEX,SINDEX 7504568Sgibbs call one_stcnt # xfer one byte 7514568Sgibbs mov DINDIR,SCSIDATL 7524568Sgibbsinb1: 7534568Sgibbs test SSTAT0,0x4 jz inb1 # SDONE - wait to "finish" 7544568Sgibbs ret 7554568Sgibbs 7564568Sgibbs# Carefully read data in Automatic PIO mode. I first tried this using 7574568Sgibbs# Manual PIO mode, but it gave me continual underrun errors, probably 7584568Sgibbs# indicating that I did something wrong, but I feel more secure leaving 7594568Sgibbs# Automatic PIO on all the time. 7604568Sgibbs# 7614568Sgibbs# According to Adaptec's documentation, an ACK is not sent on input from 7624568Sgibbs# the target until SCSIDATL is read from. So we wait until SCSIDATL is 7634568Sgibbs# latched (the usual way), then read the data byte directly off the bus 7644568Sgibbs# using SCSIBUSL. When we have pulled the ATN line, or we just want to 7654568Sgibbs# acknowledge the byte, then we do a dummy read from SCISDATL. The SCSI 7664568Sgibbs# spec guarantees that the target will hold the data byte on the bus until 7674568Sgibbs# we send our ACK. 7684568Sgibbs# 7694568Sgibbs# The assumption here is that these are called in a particular sequence, 7704568Sgibbs# and that REQ is already set when inb_first is called. inb_{first,next} 7714568Sgibbs# use the same calling convention as inb. 7724568Sgibbs# 7734568Sgibbsinb_first: 7744568Sgibbs mov DINDEX,SINDEX 7754568Sgibbs mov DINDIR,SCSIBUSL ret # read byte directly from bus 7764568Sgibbs 7774568Sgibbsinb_next: 7784568Sgibbs mov DINDEX,SINDEX # save SINDEX 7794568Sgibbs 7804568Sgibbs call one_stcnt # xfer one byte 7814568Sgibbs mov NONE,SCSIDATL # dummy read from latch to ACK 7824568Sgibbsinb_next1: 7834568Sgibbs test SSTAT0,0x4 jz inb_next1 # SDONE 7844568Sgibbsinb_next2: 7854568Sgibbs test SSTAT0,0x2 jz inb_next2 # SPIORDY - wait for next byte 7864568Sgibbs mov DINDIR,SCSIBUSL ret # read byte directly from bus 7874568Sgibbs 7884568Sgibbsinb_last: 7894568Sgibbs call one_stcnt # ACK with dummy read 7904568Sgibbs mov NONE,SCSIDATL 7914568Sgibbsinb_last1: 7924568Sgibbs test SSTAT0,0x4 jz inb_last1 # wait for completion 7934568Sgibbs ret 7944568Sgibbs 7954568Sgibbs# Output byte in Automatic PIO mode. The byte to output should be 7964568Sgibbs# in SINDEX. If DROPATN's high bit is set, then ATN will be dropped 7974568Sgibbs# before the byte is output. 7984568Sgibbs# 7994568Sgibbsoutb: 8004568Sgibbs test SSTAT0,0x2 jz outb # SPIORDY 8014568Sgibbs call one_stcnt # xfer one byte 8024568Sgibbs 8034568Sgibbs test DROPATN,0x80 jz outb1 8044568Sgibbs mvi CLRSINT1,0x40 # CLRATNO 8054568Sgibbs clr DROPATN 8064568Sgibbsoutb1: 8074568Sgibbs mov SCSIDATL,SINDEX 8084568Sgibbsoutb2: 8094568Sgibbs test SSTAT0,0x4 jz outb2 # SDONE 8104568Sgibbs ret 8114568Sgibbs 8124568Sgibbs# Write the value "1" into the STCNT registers, for Automatic PIO 8134568Sgibbs# transfers. 8144568Sgibbs# 8154568Sgibbsone_stcnt: 8164568Sgibbs clr STCNT+2 8174568Sgibbs clr STCNT+1 8184568Sgibbs mvi STCNT+0,1 ret 8194568Sgibbs 8204568Sgibbs# DMA data transfer. HADDR and HCNT must be loaded first, and 8214568Sgibbs# SINDEX should contain the value to load DFCNTRL with - 0x3d for 8224568Sgibbs# host->scsi, or 0x39 for scsi->host. The SCSI channel is cleared 8234568Sgibbs# during initialization. 8244568Sgibbs# 8254568Sgibbsdma: 8264568Sgibbs mov DFCNTRL,SINDEX 8274568Sgibbsdma1: 8284568Sgibbsdma2: 8294568Sgibbs test SSTAT0,0x1 jnz dma3 # DMADONE 8304568Sgibbs test SSTAT1,0x10 jz dma1 # PHASEMIS, ie. underrun 8314568Sgibbs 8324568Sgibbs# We will be "done" DMAing when the transfer count goes to zero, or 8334568Sgibbs# the target changes the phase (in light of this, it makes sense that 8344568Sgibbs# the DMA circuitry doesn't ACK when PHASEMIS is active). If we are 8354866Sgibbs# doing a SCSI->Host transfer, the data FIFO should be flushed auto- 8364866Sgibbs# magically on STCNT=0 or a phase change, so just wait for FIFO empty 8374866Sgibbs# status. 8384568Sgibbs# 8394568Sgibbsdma3: 8404568Sgibbs test SINDEX,0x4 jnz dma5 # DIRECTION 8414568Sgibbsdma4: 8425326Sgibbs test DFSTATUS,0x1 jz dma4 # FIFOEMP 8434568Sgibbs 8444568Sgibbs# Now shut the DMA enables off, and copy STCNT (ie. the underrun 8454568Sgibbs# amount, if any) to the SCB registers; SG_COUNT will get copied to 8464568Sgibbs# the SCB's residual S/G count field after sg_advance is called. Make 8474568Sgibbs# sure that the DMA enables are actually off first lest we get an ILLSADDR. 8484568Sgibbs# 8494568Sgibbsdma5: 8504568Sgibbs clr DFCNTRL # disable DMA 8514568Sgibbsdma6: 8524568Sgibbs test DFCNTRL,0x38 jnz dma6 # SCSIENACK|SDMAENACK|HDMAENACK 8534568Sgibbs 8544568Sgibbs mvi A,3 8554568Sgibbs mvi DINDEX,SCBARRAY+15 8564568Sgibbs mvi STCNT call bcopy 8574568Sgibbs 8584568Sgibbs ret 8594568Sgibbs 8604568Sgibbs# Common SCSI initialization for selection and reselection. Expects 8614568Sgibbs# the target SCSI ID to be in the upper four bits of SINDEX, and A's 8624568Sgibbs# contents are stomped on return. 8634568Sgibbs# 8644568Sgibbsinitialize: 8654568Sgibbs and SCSIID,0xf0,SINDEX # target ID 8665326Sgibbs test SBLKCTL,0x08 jnz initialize_b 8675326Sgibbs mvi SINDEX,SCSICONF_A 8685326Sgibbs test FLAGS,WIDE_BUS jnz initialize_wide 8695326Sgibbs and A,0x7,SCSICONF_A # SCSI_ID_A[210] 8705326Sgibbs jmp initialize_2 8715326Sgibbsinitialize_b: 8725326Sgibbs and A,0x7,SCSICONF_B # SCSI_ID_B[210] 8735326Sgibbs mvi SCSICONF_B jmp initialize_2 8745326Sgibbs 8755326Sgibbsinitialize_wide: 8765326Sgibbs and A, 0xf,SCSICONF_B 8775326Sgibbs 8785326Sgibbsinitialize_2: 8794568Sgibbs or SCSIID,A 8804568Sgibbs 8814568Sgibbs# Esundry initialization. 8824568Sgibbs# 8834568Sgibbs clr DROPATN 8844568Sgibbs clr SIGSTATE 8854568Sgibbs 8864568Sgibbs# Turn on Automatic PIO mode now, before we expect to see an REQ 8874568Sgibbs# from the target. It shouldn't hurt anything to leave it on. Set 8884568Sgibbs# CLRCHN here before the target has entered a data transfer mode - 8894568Sgibbs# with synchronous SCSI, if you do it later, you blow away some 8904568Sgibbs# data in the SCSI FIFO that the target has already sent to you. 8914568Sgibbs# 8924866Sgibbs# DFON is a 7870 bit enabling digital filtering of REQ and ACK signals. 8934866Sgibbs# 8944866Sgibbs mvi SXFRCTL0,0x8a # DFON|SPIOEN|CLRCHN 8954568Sgibbs 8964568Sgibbs# Set SCSI bus parity checking and the selection timeout value, 8974568Sgibbs# and enable the hardware selection timer. Set the SELTO interrupt 8984568Sgibbs# to signal the driver. 8994568Sgibbs# 9004866Sgibbs# STPWEN is 7870-specific, enabling an external termination power source. 9014866Sgibbs# 9025326Sgibbs and A,0x38,SINDIR # PARITY_ENB|SEL_TIM[10] 9035326Sgibbs or SXFRCTL1,0x7,A # ENSTIMER|ACTNEGEN|STPWEN 9044568Sgibbs mvi SIMODE1,0x84 # ENSELTIMO|ENSCSIPERR 9054568Sgibbs 9064568Sgibbs# Initialize scatter-gather pointers by setting up the working copy 9074568Sgibbs# in scratch RAM. 9084568Sgibbs# 9094568Sgibbs call sg_scb2ram 9104568Sgibbs 9114568Sgibbs# Initialize SCSIRATE with the appropriate value for this target. 9124568Sgibbs# 9134568Sgibbs call ndx_sdtr 9144568Sgibbs mov SCSIRATE,SINDIR 9154568Sgibbs ret 9164568Sgibbs 9174568Sgibbs# Assert that if we've been reselected, then we've seen an IDENTIFY 9184568Sgibbs# message. 9194568Sgibbs# 9204568Sgibbsassert: 9214568Sgibbs test RESELECT,0x80 jz assert1 # reselected? 9224568Sgibbs test RESELECT,0x40 jnz assert1 # seen IDENTIFY? 9234568Sgibbs 9244568Sgibbs mvi INTSTAT,SIGNAL_2 # no - cause a kernel panic 9254568Sgibbs 9264568Sgibbsassert1: 9274568Sgibbs ret 9284568Sgibbs 9294568Sgibbs# Find out if disconnection is ok from the information the BIOS has left 9305326Sgibbs# us. The tcl from SCBARRAY+1 should be in SINDEX; A will 9314866Sgibbs# contain either 0x40 (disconnection ok) or 0x00 (disconnection not ok) 9324568Sgibbs# on exit. 9334568Sgibbs# 9345326Sgibbs# To allow for wide or twin busses, we check the upper bit of the target ID 9355326Sgibbs# and the channel ID and look at the appropriate disconnect register. 9364568Sgibbs# 9374568Sgibbsdisconnect: 9384568Sgibbs and FUNCTION1,0x70,SINDEX # strip off extra just in case 9394568Sgibbs mov A,FUNCTION1 9405326Sgibbs test SINDEX, 0x88 jz disconnect_a 9415326Sgibbs 9425326Sgibbs test DISC_DSB_B,A jz disconnect1 # bit nonzero if DISabled 9435326Sgibbs clr A ret 9445326Sgibbs 9455326Sgibbsdisconnect_a: 9464568Sgibbs test DISC_DSB_A,A jz disconnect1 # bit nonzero if DISabled 9475326Sgibbs clr A ret 9484568Sgibbs 9494568Sgibbsdisconnect1: 9504568Sgibbs mvi A,0x40 ret 9514568Sgibbs 9524568Sgibbs# Locate the SCB matching the target ID in SELID and the lun in the lower 9534568Sgibbs# three bits of SINDEX, and switch the SCB to it. Have the kernel print 9544568Sgibbs# a warning message if it can't be found, and generate an ABORT message 9554866Sgibbs# to the target. We keep the value of the t/c/l that we are trying to find 9564568Sgibbs# in DINDEX so it is not overwritten during our check to see if we are 9574568Sgibbs# at the last SCB. 9584568Sgibbs# 9594568SgibbsfindSCB: 9604568Sgibbs and A,0x7,SINDEX # lun in lower three bits 9615326Sgibbs or DINDEX,A,SELID 9625326Sgibbs and DINDEX,0xf7 9635326Sgibbs and A,0x08,SBLKCTL # B Channel?? 9645326Sgibbs or DINDEX,A 9654568Sgibbs clr SINDEX 9664568Sgibbs 9674568SgibbsfindSCB1: 9684866Sgibbs mov A,DINDEX 9694568Sgibbs mov SCBPTR,SINDEX # switch to new SCB 9704568Sgibbs cmp SCBARRAY+1,A jne findSCB2 # target ID/channel/lun match? 9714568Sgibbs test SCBARRAY+0,0x4 jz findSCB2 # should be disconnected 9724568Sgibbs ret 9734568Sgibbs 9744568SgibbsfindSCB2: 9754568Sgibbs inc SINDEX 9764568Sgibbs mov A,SCBCOUNT 9774568Sgibbs cmp SINDEX,A jne findSCB1 9784568Sgibbs 9794568Sgibbs mvi INTSTAT,SIGNAL_3 # not found - signal kernel 9804568Sgibbs mvi 0x6 call mk_mesg # ABORT message 9814568Sgibbs 9824568Sgibbs or SINDEX,0x10,SIGSTATE # assert ATNO 9834568Sgibbs call scsisig 9844568Sgibbs ret 9854568Sgibbs 9864568Sgibbs# Make a working copy of the scatter-gather parameters in the SCB. 9874568Sgibbs# 9884568Sgibbssg_scb2ram: 9894568Sgibbs mov SG_COUNT,SCBARRAY+2 9904568Sgibbs 9914568Sgibbs mvi A,4 9924568Sgibbs mvi DINDEX,SG_NEXT 9934568Sgibbs mvi SCBARRAY+3 call bcopy 9944568Sgibbs 9954568Sgibbs mvi SG_NOLOAD,0x80 9964568Sgibbs test SCBARRAY+0,0x10 jnz sg_scb2ram1 # don't reload s/g? 9974568Sgibbs clr SG_NOLOAD 9984568Sgibbs 9994568Sgibbssg_scb2ram1: 10004568Sgibbs ret 10014568Sgibbs 10024568Sgibbs# Copying RAM values back to SCB, for Save Data Pointers message. 10034568Sgibbs# 10044568Sgibbssg_ram2scb: 10054568Sgibbs mov SCBARRAY+2,SG_COUNT 10064568Sgibbs 10074568Sgibbs mvi A,4 10084568Sgibbs mvi DINDEX,SCBARRAY+3 10094568Sgibbs mvi SG_NEXT call bcopy 10104568Sgibbs 10114568Sgibbs and SCBARRAY+0,0xef,SCBARRAY+0 10124568Sgibbs test SG_NOLOAD,0x80 jz sg_ram2scb1 # reload s/g? 10134568Sgibbs or SCBARRAY+0,0x10 10144568Sgibbs 10154568Sgibbssg_ram2scb1: 10164568Sgibbs ret 10174568Sgibbs 10184568Sgibbs# Load a struct scatter if needed and set up the data address and 10194568Sgibbs# length. If the working value of the SG count is nonzero, then 10204568Sgibbs# we need to load a new set of values. 10214568Sgibbs# 10224568Sgibbs# This, like the above DMA, assumes a little-endian host data storage. 10234568Sgibbs# 10244568Sgibbssg_load: 10254568Sgibbs test SG_COUNT,0xff jz sg_load3 # SG being used? 10264568Sgibbs test SG_NOLOAD,0x80 jnz sg_load3 # don't reload s/g? 10274568Sgibbs 10284568Sgibbs clr HCNT+2 10294568Sgibbs clr HCNT+1 10304568Sgibbs mvi HCNT+0,SG_SIZEOF 10314568Sgibbs 10324568Sgibbs mvi A,4 10334568Sgibbs mvi DINDEX,HADDR 10344568Sgibbs mvi SG_NEXT call bcopy 10354568Sgibbs 10364568Sgibbs mvi DFCNTRL,0xd # HDMAEN|DIRECTION|FIFORESET 10374568Sgibbs 10384568Sgibbs# Wait for DMA from host memory to data FIFO to complete, then disable 10394568Sgibbs# DMA and wait for it to acknowledge that it's off. 10404568Sgibbs# 10414568Sgibbssg_load1: 10424568Sgibbs test DFSTATUS,0x8 jz sg_load1 # HDONE 10434568Sgibbs 10444568Sgibbs clr DFCNTRL # disable DMA 10454568Sgibbssg_load2: 10464568Sgibbs test DFCNTRL,0x8 jnz sg_load2 # HDMAENACK 10474568Sgibbs 10484568Sgibbs# Copy data from FIFO into SCB data pointer and data count. This assumes 10494568Sgibbs# that the struct scatterlist has this structure (this and sizeof(struct 10504568Sgibbs# scatterlist) == 12 are asserted in aic7xxx.c): 10514568Sgibbs# 10524568Sgibbs# struct scatterlist { 10534568Sgibbs# char *address; /* four bytes, little-endian order */ 10544568Sgibbs# ... /* four bytes, ignored */ 10554568Sgibbs# unsigned short length; /* two bytes, little-endian order */ 10564568Sgibbs# } 10574568Sgibbs# 10584568Sgibbs 10594568Sgibbs# Not in FreeBSD. the scatter list is only 8 bytes. 10604568Sgibbs# 10614568Sgibbs# struct ahc_dma_seg { 10624568Sgibbs# physaddr addr; /* four bytes, little-endian order */ 10634568Sgibbs# long len; /* four bytes, little endian order */ 10644568Sgibbs# }; 10654568Sgibbs# 10664568Sgibbs 10674568Sgibbs mov SCBARRAY+19,DFDAT # new data address 10684568Sgibbs mov SCBARRAY+20,DFDAT 10694568Sgibbs mov SCBARRAY+21,DFDAT 10704568Sgibbs mov SCBARRAY+22,DFDAT 10714568Sgibbs 10724568Sgibbs mov SCBARRAY+23,DFDAT 10734568Sgibbs mov SCBARRAY+24,DFDAT 10744568Sgibbs mov SCBARRAY+25,DFDAT 10754568Sgibbs mov NONE,DFDAT #Only support 24 bit length. 10764568Sgibbs 10774568Sgibbssg_load3: 10784568Sgibbs ret 10794568Sgibbs 10804568Sgibbs# Advance the scatter-gather pointers only IF NEEDED. If SG is enabled, 10814568Sgibbs# and the SCSI transfer count is zero (note that this should be called 10824568Sgibbs# right after a DMA finishes), then move the working copies of the SG 10834568Sgibbs# pointer/length along. If the SCSI transfer count is not zero, then 10844568Sgibbs# presumably the target is disconnecting - do not reload the SG values 10854568Sgibbs# next time. 10864568Sgibbs# 10874568Sgibbssg_advance: 10884568Sgibbs test SG_COUNT,0xff jz sg_advance2 # s/g enabled? 10894568Sgibbs 10904568Sgibbs test STCNT+0,0xff jnz sg_advance1 # SCSI transfer count nonzero? 10914568Sgibbs test STCNT+1,0xff jnz sg_advance1 10924568Sgibbs test STCNT+2,0xff jnz sg_advance1 10934568Sgibbs 10944568Sgibbs clr SG_NOLOAD # reload s/g next time 10954568Sgibbs dec SG_COUNT # one less segment to go 10964568Sgibbs 10974568Sgibbs clr A # add sizeof(struct scatter) 10984568Sgibbs add SG_NEXT+0,SG_SIZEOF,SG_NEXT+0 10994568Sgibbs adc SG_NEXT+1,A,SG_NEXT+1 11004568Sgibbs adc SG_NEXT+2,A,SG_NEXT+2 11014568Sgibbs adc SG_NEXT+3,A,SG_NEXT+3 11024568Sgibbs 11034568Sgibbs ret 11044568Sgibbs 11054568Sgibbssg_advance1: 11064568Sgibbs mvi SG_NOLOAD,0x80 # don't reload s/g next time 11074568Sgibbssg_advance2: 11084568Sgibbs ret 11094568Sgibbs 11104568Sgibbs# Add the array base SYNCNEG to the target offset (the target address 11114568Sgibbs# is in SCSIID), and return the result in SINDEX. The accumulator 11124568Sgibbs# contains the 3->8 decoding of the target ID on return. 11134568Sgibbs# 11144568Sgibbsndx_sdtr: 11154568Sgibbs shr A,SCSIID,4 11165326Sgibbs test SBLKCTL,0x08 jz ndx_sdtr_2 11175326Sgibbs or A,0x08 # Channel B entries add 8 11185326Sgibbsndx_sdtr_2: 11194568Sgibbs add SINDEX,SYNCNEG,A 11204568Sgibbs 11214568Sgibbs and FUNCTION1,0x70,SCSIID # 3-bit target address decode 11224568Sgibbs mov A,FUNCTION1 ret 11234568Sgibbs 11244568Sgibbs# If we need to negotiate transfer parameters, build the SDTR message 11254568Sgibbs# starting at the address passed in SINDEX. DINDEX is modified on return. 11264568Sgibbs# 11274568Sgibbsmk_sdtr: 11284568Sgibbs mov DINDEX,SINDEX # save SINDEX 11294568Sgibbs 11304568Sgibbs call ndx_sdtr 11315326Sgibbs test SCBARRAY+1,0x88 jz mk_sdtr1_a 11325326Sgibbs test NEEDSDTR_B,A jnz mk_sdtr1 # do we need negotiation? 11334568Sgibbs ret 11345326Sgibbsmk_sdtr1_a: 11355326Sgibbs test NEEDSDTR_A,A jnz mk_sdtr1 # do we need negotiation? 11365326Sgibbs ret 11374568Sgibbs 11384568Sgibbsmk_sdtr1: 11394568Sgibbs mvi DINDIR,1 # extended message 11404568Sgibbs mvi DINDIR,3 # extended message length = 3 11414568Sgibbs mvi DINDIR,1 # SDTR code 11424568Sgibbs mvi DINDIR,25 # REQ/ACK transfer period 11434568Sgibbs mvi DINDIR,15 # REQ/ACK offset 11444568Sgibbs 11454568Sgibbs add MSG_LEN,-MSG_START+0,DINDEX # update message length 11464568Sgibbs ret 11474568Sgibbs 11484568Sgibbs# Set SCSI bus control signal state. This also saves the last-written 11494568Sgibbs# value into a location where the higher-level driver can read it - if 11504568Sgibbs# it has to send an ABORT or RESET message, then it needs to know this 11514568Sgibbs# so it can assert ATN without upsetting SCSISIGO. The new value is 11524568Sgibbs# expected in SINDEX. Change the actual state last to avoid contention 11534568Sgibbs# from the driver. 11544568Sgibbs# 11554568Sgibbsscsisig: 11564568Sgibbs mov SIGSTATE,SINDEX 11574568Sgibbs mov SCSISIGO,SINDEX ret 1158