aic7xxx.seq revision 13313
113177Sgibbs/*+M*********************************************************************** 213177Sgibbs *Adaptec 274x/284x/294x device driver for Linux and FreeBSD. 313177Sgibbs * 413177Sgibbs *Copyright (c) 1994 John Aycock 513177Sgibbs * The University of Calgary Department of Computer Science. 613177Sgibbs * All rights reserved. 713177Sgibbs * 813177Sgibbs *Modifications/enhancements: 913177Sgibbs * Copyright (c) 1994, 1995 Justin Gibbs. All rights reserved. 1013177Sgibbs * 1113177Sgibbs *Redistribution and use in source and binary forms, with or without 1213177Sgibbs *modification, are permitted provided that the following conditions 1313177Sgibbs *are met: 1413177Sgibbs *1. Redistributions of source code must retain the above copyright 1513177Sgibbs * notice, this list of conditions, and the following disclaimer. 1613177Sgibbs *2. Redistributions in binary form must reproduce the above copyright 1713177Sgibbs * notice, this list of conditions and the following disclaimer in the 1813177Sgibbs * documentation and/or other materials provided with the distribution. 1913177Sgibbs *3. All advertising materials mentioning features or use of this software 2013177Sgibbs * must display the following acknowledgement: 2113177Sgibbs * This product includes software developed by the University of Calgary 2213177Sgibbs * Department of Computer Science and its contributors. 2313177Sgibbs *4. Neither the name of the University nor the names of its contributors 2413177Sgibbs * may be used to endorse or promote products derived from this software 2513177Sgibbs * without specific prior written permission. 2613177Sgibbs * 2713177Sgibbs *THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 2813177Sgibbs *ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2913177Sgibbs *IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 3013177Sgibbs *ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 3113177Sgibbs *FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 3213177Sgibbs *DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 3313177Sgibbs *OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 3413177Sgibbs *HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 3513177Sgibbs *LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3613177Sgibbs *OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3713177Sgibbs *SUCH DAMAGE. 3813177Sgibbs * 3913177Sgibbs *FreeBSD, Twin, Wide, 2 command per target support, tagged queuing and other 4013177Sgibbs *optimizations provided by Justin T. Gibbs (gibbs@FreeBSD.org) 4113177Sgibbs * 4213177Sgibbs *-M************************************************************************/ 434568Sgibbs 4413313SgibbsVERSION AIC7XXX_SEQ_VER "$Id: aic7xxx.seq,v 1.26 1996/01/05 16:11:49 gibbs Exp $" 455647Sgibbs 4613177Sgibbs#include "../../dev/aic7xxx/aic7xxx_reg.h" 474568Sgibbs 4813177Sgibbs/* 4913177Sgibbs * We can't just use ACCUM in the sequencer code because it 5013177Sgibbs * must be treated specially by the assembler, and it currently 5113177Sgibbs * looks for the symbol 'A'. This is the only register defined 5213177Sgibbs * the assembler's symbol space. 5313177Sgibbs */ 5413177SgibbsA = ACCUM 554568Sgibbs 5613177Sgibbs/* After starting the selection hardware, we return to the "poll_for_work" 5713177Sgibbs * loop so that we can check for reconnecting targets as well as for our 5813177Sgibbs * selection to complete just in case the reselection wins bus arbitration. 5913177Sgibbs * The problem with this is that we must keep track of the SCB that we've 6013177Sgibbs * already pulled from the QINFIFO and started the selection on just in case 6113177Sgibbs * the reselection wins so that we can retry the selection at a later time. 6213177Sgibbs * This problem cannot be resolved by holding a single entry in scratch 6313177Sgibbs * ram since a reconnecting target can request sense and this will create 6413177Sgibbs * yet another SCB waiting for selection. The solution used here is to 6513177Sgibbs * use byte 31 of the SCB as a psuedo-next pointer and to thread a list 6613177Sgibbs * of SCBs that are awaiting selection. Since 0-0xfe are valid SCB offsets, 6713177Sgibbs * SCB_LIST_NULL is 0xff which is out of range. The kernel driver must 6813177Sgibbs * add an entry to this list everytime a request sense occurs. The sequencer 6913177Sgibbs * will automatically consume the entries. 7013177Sgibbs */ 714568Sgibbs 7213177Sgibbs/* 7313177Sgibbs * Initialize any state idle loop state here. This code is executed on 7413177Sgibbs * startup and after every bus free. 7513177Sgibbs */ 7613177Sgibbsstart: 7713177Sgibbs mvi SCSISEQ,ENRSELI /* Always allow reselection */ 788104Sgibbspoll_for_work: 7913177Sgibbs /* 8013177Sgibbs * Are we a twin channel device? 8113177Sgibbs * For fairness, we check the other bus first, 8213177Sgibbs * since we just finished a transaction on the 8313177Sgibbs * current channel. 8413177Sgibbs */ 8513177Sgibbs test FLAGS,TWIN_BUS jz start2 8613177Sgibbs xor SBLKCTL,SELBUSB /* Toggle to the other bus */ 878104Sgibbs test SSTAT0,SELDI jnz reselect 8813177Sgibbs xor SBLKCTL,SELBUSB /* Toggle to the original bus */ 895326Sgibbsstart2: 908104Sgibbs test SSTAT0,SELDI jnz reselect 919395Sgibbs cmp WAITING_SCBH,SCB_LIST_NULL jne start_waiting 9213177Sgibbs test QINCNT,0xff jz poll_for_work 934568Sgibbs 9413177Sgibbs/* We have at least one queued SCB now and we don't have any 9513177Sgibbs * SCBs in the list of SCBs awaiting selection. Set the SCB 9613177Sgibbs * pointer from the FIFO so we see the right bank of SCB 9713177Sgibbs * registers. 9813177Sgibbs */ 994568Sgibbs mov SCBPTR,QINFIFO 1004568Sgibbs 10113177Sgibbs/* 10213177Sgibbs * If the control byte of this SCB has the NEEDDMA flag set, we have 10313177Sgibbs * yet to DMA it from host memory 10413177Sgibbs */ 1055647Sgibbs 10613177Sgibbstest SCB_CONTROL,NEEDDMA jz test_busy 10713177Sgibbs clr HCNT2 10813177Sgibbs clr HCNT1 10913177Sgibbs mvi HCNT0,SCB_SIZEOF 1105647Sgibbs 1118104Sgibbs mvi DINDEX,HADDR 11213177Sgibbs mvi SCB_PHYSADDR call bcopy_4 1138104Sgibbs 11413177Sgibbs mvi DFCNTRL,0xd /* HDMAEN|DIRECTION|FIFORESET */ 1155647Sgibbs 11613177Sgibbs/* 11713177Sgibbs * Wait for DMA from host memory to data FIFO to complete, then disable 11813177Sgibbs * DMA and wait for it to acknowledge that it's off. 11913177Sgibbs */ 1207532Sgibbs call dma_finish 1215647Sgibbs 12213177Sgibbs/* Copy the SCB from the FIFO to the SCBARRAY */ 1235647Sgibbs 12413177Sgibbs mvi DINDEX, SCBARRAY 1259928Sgibbs call bcopy_5_dfdat 1269928Sgibbs call bcopy_7_dfdat 1279928Sgibbs call bcopy_7_dfdat 1289928Sgibbs call bcopy_7_dfdat 1298104Sgibbs 13013177Sgibbs/* 13113177Sgibbs * See if there is not already an active SCB for this target. This code 13213177Sgibbs * locks out on a per target basis instead of target/lun. Although this 13313177Sgibbs * is not ideal for devices that have multiple luns active at the same 13413177Sgibbs * time, it is faster than looping through all SCB's looking for active 13513177Sgibbs * commands. It may be benificial to make findscb a more general procedure 13613177Sgibbs * to see if the added cost of the search is negligible. This code also 13713177Sgibbs * assumes that the kernel driver will clear the active flags on board 13813177Sgibbs * initialization, board reset, and a target SELTO. Tagged commands 13913177Sgibbs * don't set the active bits since you can have more than queue more 14013177Sgibbs * than one command at a time. We do, however, look to see if there 14113177Sgibbs * are any non-tagged I/Os in progress, and requeue the command if 14213177Sgibbs * there are. Tagged and non-tagged commands cannot be mixed to a 14313177Sgibbs * single target. 14413177Sgibbs */ 1454568Sgibbs 1465647Sgibbstest_busy: 14713177Sgibbs mov FUNCTION1,SCB_TCL 1484568Sgibbs mov A,FUNCTION1 14913177Sgibbs test SCB_TCL,0x88 jz test_a /* Id < 8 && A channel */ 1505326Sgibbs 1515326Sgibbs test ACTIVE_B,A jnz requeue 15213177Sgibbs test SCB_CONTROL,TAG_ENB jnz start_scb 15313177Sgibbs /* Mark the current target as busy */ 15413177Sgibbs or ACTIVE_B,A 1555326Sgibbs jmp start_scb 1565326Sgibbs 15713177Sgibbs/* Place the currently active SCB back on the queue for later processing */ 1585326Sgibbsrequeue: 1594568Sgibbs mov QINFIFO, SCBPTR 1608104Sgibbs jmp poll_for_work 1614568Sgibbs 16213177Sgibbs/* 16313177Sgibbs * Pull the first entry off of the waiting for selection list 16413177Sgibbs * We don't have to "test_busy" because only transactions that 16513177Sgibbs * have passed that test can be in the waiting_scb list. 16613177Sgibbs */ 1678104Sgibbsstart_waiting: 1688104Sgibbs mov SCBPTR,WAITING_SCBH 16913177Sgibbs jmp start_scb2 1708104Sgibbs 1715326Sgibbstest_a: 17213177Sgibbs test ACTIVE_A,A jnz requeue 17313177Sgibbs test SCB_CONTROL,TAG_ENB jnz start_scb 17413177Sgibbs /* Mark the current target as busy */ 17513177Sgibbs or ACTIVE_A,A 1765326Sgibbs 1775326Sgibbsstart_scb: 17813177Sgibbs mov SCB_NEXT_WAITING,WAITING_SCBH 17913177Sgibbs mov WAITING_SCBH, SCBPTR 18013177Sgibbsstart_scb2: 18113177Sgibbs and SINDEX,0xf7,SBLKCTL /* Clear the channel select bit */ 18213177Sgibbs and A,0x08,SCB_TCL /* Get new channel bit */ 18313177Sgibbs or SINDEX,A 18413177Sgibbs mov SBLKCTL,SINDEX /* select channel */ 18513177Sgibbs mov SCB_TCL call initialize_scsiid 1868104Sgibbs 18713177Sgibbs/* 18813177Sgibbs * Enable selection phase as an initiator, and do automatic ATN 18913177Sgibbs * after the selection. We do this now so that we can overlap the 19013177Sgibbs * rest of our work to set up this target with the arbitration and 19113177Sgibbs * selection bus phases. 19213177Sgibbs */ 1938104Sgibbsstart_selection: 19413177Sgibbs mvi SCSISEQ,0x58 /* ENSELO|ENAUTOATNO|ENRSELI */ 1954568Sgibbs 19613177Sgibbs/* 19713177Sgibbs * As soon as we get a successful selection, the target should go 19813177Sgibbs * into the message out phase since we have ATN asserted. Prepare 19913177Sgibbs * the message to send. 20013177Sgibbs * 20113177Sgibbs * Messages are stored in scratch RAM starting with a length byte 20213177Sgibbs * followed by the message itself. 20313177Sgibbs */ 20413177Sgibbs test SCB_CMDLEN,0xff jnz mk_identify /* 0 Length Command? */ 2058567Sdg 20613177Sgibbs/* 20713177Sgibbs * The kernel has sent us an SCB with no command attached. This implies 20813177Sgibbs * that the kernel wants to send a message of some sort to this target, 20913177Sgibbs * so we interrupt the driver, allow it to fill the message buffer, and 21013177Sgibbs * then go back into the arbitration loop 21113177Sgibbs */ 2128567Sdg mvi INTSTAT,AWAITING_MSG 2139917Sgibbs jmp wait_for_selection 2148567Sdg 21513177Sgibbsmk_identify: 21613177Sgibbs and A,DISCENB,SCB_CONTROL /* mask off disconnect privledge */ 2174568Sgibbs 21813177Sgibbs and SINDEX,0x7,SCB_TCL /* lun */ 21913177Sgibbs or SINDEX,A /* or in disconnect privledge */ 22013177Sgibbs or SINDEX,MSG_IDENTIFY call mk_mesg /* IDENTIFY message */ 2214568Sgibbs 22213177Sgibbs test SCB_CONTROL,0xb0 jz !message /* WDTR, SDTR or TAG?? */ 22313177Sgibbs/* 22413177Sgibbs * Tag Message if Tag enabled in SCB control block. Use SCBPTR as the tag 22513177Sgibbs * value 22613177Sgibbs */ 2274568Sgibbs 2286608Sgibbsmk_tag: 22913177Sgibbs mvi DINDEX, MSG1 23013177Sgibbs test SCB_CONTROL,TAG_ENB jz mk_tag_done 23113177Sgibbs and A,0x23,SCB_CONTROL 2326608Sgibbs mov DINDIR,A 2336608Sgibbs mov DINDIR,SCBPTR 2346608Sgibbs 23513177Sgibbs add MSG_LEN,COMP_MSG0,DINDEX /* update message length */ 2366608Sgibbs 2376608Sgibbsmk_tag_done: 2386608Sgibbs 23913177Sgibbs mov DINDEX call mk_dtr /* build DTR message if needed */ 2406608Sgibbs 2414568Sgibbs!message: 2429917Sgibbswait_for_selection: 24313177Sgibbs test SSTAT0,SELDO jnz select 24413177Sgibbs test SSTAT0,SELDI jz wait_for_selection 2454568Sgibbs 24613177Sgibbs/* 24713177Sgibbs * Reselection has been initiated by a target. Make a note that we've been 24813177Sgibbs * reselected, but haven't seen an IDENTIFY message from the target 24913177Sgibbs * yet. 25013177Sgibbs */ 2514568Sgibbsreselect: 25213177Sgibbs clr MSG_LEN /* Don't have anything in the mesg buffer */ 2538104Sgibbs mov SELID call initialize_scsiid 25413177Sgibbs mvi SAVED_TCL, 0xff /* 25513177Sgibbs * Fill with an imposible value so we 25613177Sgibbs * don't get false hits for a tag 25713177Sgibbs * without an identify. 25813177Sgibbs */ 25913177Sgibbs and FLAGS,0x03 /* clear target specific flags */ 26013177Sgibbs or FLAGS,RESELECTED 26113177Sgibbs jmp select2 2624568Sgibbs 26313177Sgibbs/* 26413177Sgibbs * After the selection, remove this SCB from the "waiting for selection" 26513177Sgibbs * list. This is achieved by simply moving our "next" pointer into 26613177Sgibbs * WAITING_SCBH. Our next pointer will be set to null the next time this 26713177Sgibbs * SCB is used, so don't bother with it now. 26813177Sgibbs */ 2698104Sgibbsselect: 27013177Sgibbs and FLAGS,0x03 /* Clear target flags */ 27113177Sgibbs or SCB_CONTROL,NEEDDMA 27213177Sgibbs 27313177Sgibbs /* 27413177Sgibbs * Some drives will issue a simple tag message during 27513177Sgibbs * a tagged selection if they are immediately ready 27613177Sgibbs * to handle the command without a disconnect. Ensure 27713177Sgibbs * that SAVED_TCL (used in get_tag) is inialized correctly 27813177Sgibbs * during a selection for this reason. 27913177Sgibbs */ 28013177Sgibbs mov SAVED_TCL, SCB_TCL 28113177Sgibbs mov WAITING_SCBH,SCB_NEXT_WAITING 2828104Sgibbsselect2: 28313177Sgibbs/* 28413177Sgibbs * Set CLRCHN here before the target has entered a data transfer mode - 28513177Sgibbs * with synchronous SCSI, if you do it later, you blow away some 28613177Sgibbs * data in the SCSI FIFO that the target has already sent to you. 28713177Sgibbs */ 28813177Sgibbs clr SIGSTATE 2894568Sgibbs 29013177Sgibbs or SXFRCTL0,CLRCHN 29113177Sgibbs/* 29213177Sgibbs * Initialize SCSIRATE with the appropriate value for this target. 29313177Sgibbs */ 29413177Sgibbs call ndx_dtr 29513177Sgibbs mov SCSIRATE,SINDIR 29613177Sgibbs 29713177Sgibbs mvi SCSISEQ,ENAUTOATNP /* 29813177Sgibbs * ATN on parity errors 29913177Sgibbs * for "in" phases 30013177Sgibbs */ 30113177Sgibbs mvi CLRSINT1,CLRBUSFREE 30213177Sgibbs mvi CLRSINT0,0x60 /* CLRSELDI|CLRSELDO */ 30313177Sgibbs 30413177Sgibbs/* 30513177Sgibbs * Main loop for information transfer phases. If BSY is false, then 30613177Sgibbs * we have a bus free condition, expected or not. Otherwise, wait 30713177Sgibbs * for the target to assert REQ before checking MSG, C/D and I/O 30813177Sgibbs * for the bus phase. 30913177Sgibbs * 31013177Sgibbs */ 3114568SgibbsITloop: 31213177Sgibbs test SSTAT1,BUSFREE jnz p_busfree 31313177Sgibbs test SSTAT1,REQINIT jz ITloop 3144568Sgibbs 31513177Sgibbs and A,PHASE_MASK,SCSISIGI 3164568Sgibbs 31711829Sgibbs mov A call scsisig 3184568Sgibbs cmp ALLZEROS,A je p_dataout 31913177Sgibbs cmp A,P_DATAIN je p_datain 32013177Sgibbs cmp A,P_COMMAND je p_command 32113177Sgibbs cmp A,P_MESGOUT je p_mesgout 32213177Sgibbs cmp A,P_STATUS je p_status 32313177Sgibbs cmp A,P_MESGIN je p_mesgin 3244568Sgibbs 32513177Sgibbs mvi INTSTAT,BAD_PHASE /* unknown phase - signal driver */ 3264568Sgibbs 3274568Sgibbsp_dataout: 32813177Sgibbs mvi DMAPARAMS,0x7d /* 32913177Sgibbs * WIDEODD|SCSIEN|SDMAEN|HDMAEN| 33013177Sgibbs * DIRECTION|FIFORESET 33113177Sgibbs */ 3329928Sgibbs jmp data_phase_init 3334568Sgibbs 33413177Sgibbs/* 33513177Sgibbs * If we re-enter the data phase after going through another phase, the 33613177Sgibbs * STCNT may have been cleared, so restore it from the residual field. 33713177Sgibbs */ 3389928Sgibbsdata_phase_reinit: 3399928Sgibbs mvi DINDEX, STCNT 34013177Sgibbs mvi SCB_RESID_DCNT call bcopy_3 3419928Sgibbs jmp data_phase_loop 3424568Sgibbs 3439928Sgibbsp_datain: 34413177Sgibbs mvi DMAPARAMS,0x79 /* 34513177Sgibbs * WIDEODD|SCSIEN|SDMAEN|HDMAEN| 34613177Sgibbs * !DIRECTION|FIFORESET 34713177Sgibbs */ 3489928Sgibbsdata_phase_init: 3499928Sgibbs call assert 3505775Sgibbs 3519928Sgibbs test FLAGS, DPHASE jnz data_phase_reinit 3529928Sgibbs call sg_scb2ram 35313177Sgibbs or FLAGS, DPHASE /* We have seen a data phase */ 3544568Sgibbs 3559928Sgibbsdata_phase_loop: 35613177Sgibbs/* If we are the last SG block, don't set wideodd. */ 3579928Sgibbs cmp SG_COUNT,0x01 jne data_phase_wideodd 35813177Sgibbs and DMAPARAMS, 0xbf /* Turn off WIDEODD */ 3599928Sgibbsdata_phase_wideodd: 3609928Sgibbs mov DMAPARAMS call dma 3614568Sgibbs 36213177Sgibbs/* Exit if we had an underrun */ 36313177Sgibbs test SSTAT0,SDONE jz data_phase_finish /* underrun STCNT != 0 */ 3647532Sgibbs 36513177Sgibbs/* 36613177Sgibbs * Advance the scatter-gather pointers if needed 36713177Sgibbs */ 3689928Sgibbssg_advance: 36913177Sgibbs dec SG_COUNT /* one less segment to go */ 3704568Sgibbs 37113177Sgibbs test SG_COUNT, 0xff jz data_phase_finish /* Are we done? */ 3724568Sgibbs 37313177Sgibbs clr A /* add sizeof(struct scatter) */ 37413177Sgibbs add SG_NEXT0,SG_SIZEOF,SG_NEXT0 37513177Sgibbs adc SG_NEXT1,A,SG_NEXT1 37613177Sgibbs adc SG_NEXT2,A,SG_NEXT2 37713177Sgibbs adc SG_NEXT3,A,SG_NEXT3 3784568Sgibbs 37913177Sgibbs/* 38013177Sgibbs * Load a struct scatter and set up the data address and length. 38113177Sgibbs * If the working value of the SG count is nonzero, then 38213177Sgibbs * we need to load a new set of values. 38313177Sgibbs * 38413177Sgibbs * This, like all DMA's, assumes a little-endian host data storage. 38513177Sgibbs */ 3869928Sgibbssg_load: 38713177Sgibbs clr HCNT2 38813177Sgibbs clr HCNT1 38913177Sgibbs mvi HCNT0,SG_SIZEOF 3904568Sgibbs 3919928Sgibbs mvi DINDEX,HADDR 3929928Sgibbs mvi SG_NEXT call bcopy_4 3934568Sgibbs 39413177Sgibbs mvi DFCNTRL,0xd /* HDMAEN|DIRECTION|FIFORESET */ 3959928Sgibbs 39613177Sgibbs/* 39713177Sgibbs * Wait for DMA from host memory to data FIFO to complete, then disable 39813177Sgibbs * DMA and wait for it to acknowledge that it's off. 39913177Sgibbs */ 4009928Sgibbs call dma_finish 4019928Sgibbs 40213177Sgibbs/* 40313177Sgibbs * Copy data from FIFO into SCB data pointer and data count. This assumes 40413177Sgibbs * that the struct scatterlist has this structure (this and sizeof(struct 40513177Sgibbs * scatterlist) == 12 are asserted in aic7xxx.c): 40613177Sgibbs * 40713177Sgibbs * struct scatterlist { 40813177Sgibbs * char *address; four bytes, little-endian order 40913177Sgibbs * ... four bytes, ignored 41013177Sgibbs * unsigned short length; two bytes, little-endian order 41113177Sgibbs * } 41213177Sgibbs * 41313177Sgibbs * 41413177Sgibbs * Not in FreeBSD. the scatter list entry is only 8 bytes. 41513177Sgibbs * 41613177Sgibbs * struct ahc_dma_seg { 41713177Sgibbs * physaddr addr; four bytes, little-endian order 41813177Sgibbs * long len; four bytes, little endian order 41913177Sgibbs * }; 42013177Sgibbs */ 4219928Sgibbs 42213177Sgibbs/* 42313177Sgibbs * For Linux, we must throw away four bytes since there is a 32bit gap 42413177Sgibbs * in the middle of a struct scatterlist 42513177Sgibbs */ 42613177Sgibbs#ifdef LINUX 42713177Sgibbs call bcopy_4_dfdat 42813177Sgibbs mov NONE,DFDAT 42913177Sgibbs mov NONE,DFDAT 43013177Sgibbs mov NONE,DFDAT 43113177Sgibbs mov NONE,DFDAT 43213177Sgibbs call bcopy_3_dfdat /* Only support 24 bit length. */ 43313177Sgibbs#else 43413177Sgibbs/* 43513177Sgibbs * For FreeBSD, just copy it wholesale 43613177Sgibbs */ 4375775Sgibbs mvi DINDEX,HADDR 4389928Sgibbs call bcopy_7_dfdat 43913177Sgibbs#endif 4404568Sgibbs 44113177Sgibbs/* Load STCNT as well. It is a mirror of HCNT */ 4424568Sgibbs mvi DINDEX,STCNT 4439928Sgibbs mvi HCNT call bcopy_3 4449928Sgibbs test SSTAT1,PHASEMIS jz data_phase_loop 4454568Sgibbs 4469928Sgibbsdata_phase_finish: 44713177Sgibbs/* 44813177Sgibbs * After a DMA finishes, save the SG and STCNT residuals back into the SCB 44913177Sgibbs * We use STCNT instead of HCNT, since it's a reflection of how many bytes 45013177Sgibbs * were transferred on the SCSI (as opposed to the host) bus. 45113177Sgibbs */ 45213177Sgibbs mvi DINDEX,SCB_RESID_DCNT 45313177Sgibbs mvi STCNT call bcopy_3 45413177Sgibbs mov SCB_RESID_SGCNT, SG_COUNT 4554568Sgibbs jmp ITloop 4564568Sgibbs 45713177Sgibbs/* 45813177Sgibbs * Command phase. Set up the DMA registers and let 'er rip - the 45913177Sgibbs * two bytes after the SCB SCSI_cmd_length are zeroed by the driver, 46013177Sgibbs * so we can copy those three bytes directly into HCNT. 46113177Sgibbs */ 4624568Sgibbsp_command: 4634568Sgibbs call assert 4644568Sgibbs 46513177Sgibbs/* 46613177Sgibbs * Load HADDR and HCNT. We can do this in one bcopy since they are neighbors 46713177Sgibbs */ 4685775Sgibbs mvi DINDEX,HADDR 46913177Sgibbs mvi SCB_CMDPTR call bcopy_7 4704568Sgibbs 4714568Sgibbs mvi DINDEX,STCNT 47213177Sgibbs mvi SCB_CMDLEN call bcopy_3 4734568Sgibbs 4744568Sgibbs mvi 0x3d call dma # SCSIEN|SDMAEN|HDMAEN| 4754568Sgibbs # DIRECTION|FIFORESET 4764568Sgibbs jmp ITloop 4774568Sgibbs 47813177Sgibbs/* 47913177Sgibbs * Status phase. Wait for the data byte to appear, then read it 48013177Sgibbs * and store it into the SCB. 48113177Sgibbs */ 4824568Sgibbsp_status: 48313177Sgibbs mvi SCB_TARGET_STATUS call inb_first 4849954Sgibbs jmp mesgin_done 4854568Sgibbs 48613177Sgibbs/* 48713177Sgibbs * Message out phase. If there is no active message, but the target 48813177Sgibbs * took us into this phase anyway, build a no-op message and send it. 48913177Sgibbs */ 4904568Sgibbsp_mesgout: 49113177Sgibbs test MSG_LEN, 0xff jnz p_mesgout_start 49213177Sgibbs mvi MSG_NOP call mk_mesg /* build NOP message */ 4934568Sgibbs 49413177Sgibbsp_mesgout_start: 49513177Sgibbs/* 49613177Sgibbs * Set up automatic PIO transfer from MSG0. Bit 3 in 49713177Sgibbs * SXFRCTL0 (SPIOEN) is already on. 49813177Sgibbs */ 49913177Sgibbs mvi SINDEX,MSG0 5004568Sgibbs mov DINDEX,MSG_LEN 5014568Sgibbs 50213177Sgibbs/* 50313177Sgibbs * When target asks for a byte, drop ATN if it's the last one in 50413177Sgibbs * the message. Otherwise, keep going until the message is exhausted. 50513177Sgibbs * 50613177Sgibbs * Keep an eye out for a phase change, in case the target issues 50713177Sgibbs * a MESSAGE REJECT. 50813177Sgibbs */ 50913177Sgibbsp_mesgout_loop: 51013313Sgibbs test SSTAT1,PHASEMIS jnz p_mesgout_phasemis 51113177Sgibbs test SSTAT0,SPIORDY jz p_mesgout_loop 51213177Sgibbs cmp DINDEX,1 jne p_mesgout_outb /* last byte? */ 51313177Sgibbs mvi CLRSINT1,CLRATNO /* drop ATN */ 51413177Sgibbsp_mesgout_outb: 51513313Sgibbs or SXFRCTL0, CLRSTCNT 51613313Sgibbs mvi STCNT0, 1 51713177Sgibbs dec DINDEX 5184568Sgibbs mov SCSIDATL,SINDIR 51913313Sgibbsp_mesgout_outb_wait: 52013313Sgibbs test SSTAT0,SDONE jz p_mesgout_outb_wait 52113313Sgibbs 5224568Sgibbsp_mesgout4: 52313177Sgibbs test DINDEX,0xff jnz p_mesgout_loop 5244568Sgibbs 52513177Sgibbs/* 52613177Sgibbs * If the next bus phase after ATN drops is a message out, it means 52713177Sgibbs * that the target is requesting that the last message(s) be resent. 52813177Sgibbs */ 52913177Sgibbsp_mesgout_snoop: 53013177Sgibbs test SSTAT1,BUSFREE jnz p_mesgout_done 53113177Sgibbs test SSTAT1,REQINIT jz p_mesgout_snoop 5324568Sgibbs 53313177Sgibbs test SSTAT1,PHASEMIS jnz p_mesgout_done 5344568Sgibbs 53513177Sgibbs or SINDEX,0x10,SIGSTATE /* turn on ATNO */ 53613177Sgibbs call scsisig /* ATNO - re-assert ATN */ 53713177Sgibbs 5384568Sgibbs jmp ITloop 5394568Sgibbs 54013177Sgibbsp_mesgout_phasemis: 54113177Sgibbs mvi CLRSINT1,CLRATNO /* Be sure turn ATNO off */ 54213177Sgibbsp_mesgout_done: 54313177Sgibbs clr MSG_LEN /* no active msg */ 5444568Sgibbs jmp ITloop 5454568Sgibbs 54613177Sgibbs/* 54713177Sgibbs * Message in phase. Bytes are read using Automatic PIO mode. 54813177Sgibbs */ 5494568Sgibbsp_mesgin: 55013177Sgibbs mvi A call inb_first /* read the 1st message byte */ 55113177Sgibbs mov REJBYTE,A /* save it for the driver */ 5524568Sgibbs 55313177Sgibbs test A,MSG_IDENTIFY jnz mesgin_identify 55413177Sgibbs cmp A,MSG_DISCONNECT je mesgin_disconnect 55513177Sgibbs cmp A,MSG_SDPTRS je mesgin_sdptrs 55613177Sgibbs cmp ALLZEROS,A je mesgin_complete 55713177Sgibbs cmp A,MSG_RDPTRS je mesgin_rdptrs 55813177Sgibbs cmp A,MSG_EXTENDED je mesgin_extended 55913177Sgibbs cmp A,MSG_REJECT je mesgin_reject 5604568Sgibbs 5619954Sgibbsrej_mesgin: 56213177Sgibbs/* 56313177Sgibbs * We have no idea what this message in is, and there's no way 56413177Sgibbs * to pass it up to the kernel, so we issue a message reject and 56513177Sgibbs * hope for the best. Since we're now using manual PIO mode to 56613177Sgibbs * read in the message, there should no longer be a race condition 56713177Sgibbs * present when we assert ATN. In any case, rejection should be a 56813177Sgibbs * rare occurrence - signal the driver when it happens. 56913177Sgibbs */ 57013177Sgibbs or SINDEX,0x10,SIGSTATE /* turn on ATNO */ 5719954Sgibbs call scsisig 57213177Sgibbs mvi INTSTAT,SEND_REJECT /* let driver know */ 5739954Sgibbs 57413177Sgibbs mvi MSG_REJECT call mk_mesg 5759954Sgibbs 5769954Sgibbsmesgin_done: 57713177Sgibbs call inb_last /*ack & turn auto PIO back on*/ 5789954Sgibbs jmp ITloop 5799954Sgibbs 5809954Sgibbs 5819954Sgibbsmesgin_complete: 58213177Sgibbs/* 58313177Sgibbs * We got a "command complete" message, so put the SCB pointer 58413177Sgibbs * into the Queue Out, and trigger a completion interrupt. 58513177Sgibbs * Check status for non zero return and interrupt driver if needed 58613177Sgibbs * This allows the driver to interpret errors only when they occur 58713177Sgibbs * instead of always uploading the scb. If the status is SCSI_CHECK, 58813177Sgibbs * the driver will download a new scb requesting sense to replace 58913177Sgibbs * the old one, modify the "waiting for selection" SCB list and set 59013177Sgibbs * RETURN_1 to 0x80. If RETURN_1 is set to 0x80 the sequencer imediately 59113177Sgibbs * jumps to main loop where it will run down the waiting SCB list. 59213177Sgibbs * If the kernel driver does not wish to request sense, it need 59313177Sgibbs * only clear RETURN_1, and the command is allowed to complete. We don't 59413177Sgibbs * bother to post to the QOUTFIFO in the error case since it would require 59513177Sgibbs * extra work in the kernel driver to ensure that the entry was removed 59613177Sgibbs * before the command complete code tried processing it. 59713177Sgibbs * 59813177Sgibbs * First check for residuals 59913177Sgibbs */ 60013177Sgibbs test SCB_RESID_SGCNT,0xff jz check_status 60113177Sgibbs/* 60213177Sgibbs * If we have a residual count, interrupt and tell the host. Other 60313177Sgibbs * alternatives are to pause the sequencer on all command completes (yuck), 60413177Sgibbs * dma the resid directly to the host (slick, we may have space to do it now) 60513177Sgibbs * or have the sequencer pause itself when it encounters a non-zero resid 60613177Sgibbs * (unecessary pause just to flag the command -yuck-, but takes one instruction 60713177Sgibbs * and since it shouldn't happen that often is good enough for our purposes). 60813177Sgibbs */ 60913177Sgibbsresid: 61013177Sgibbs mvi INTSTAT,RESIDUAL 6114568Sgibbs 6127532Sgibbscheck_status: 61313177Sgibbs test SCB_TARGET_STATUS,0xff jz status_ok /* Good Status? */ 61413177Sgibbs mvi INTSTAT,BAD_STATUS /* let driver know */ 61513177Sgibbs cmp RETURN_1, SEND_SENSE jne status_ok 6169954Sgibbs jmp mesgin_done 6175326Sgibbs 6184568Sgibbsstatus_ok: 61913177Sgibbs/* First, mark this target as free. */ 62013177Sgibbs test SCB_CONTROL,TAG_ENB jnz test_immediate /* 62113177Sgibbs * Tagged commands 62213177Sgibbs * don't busy the 62313177Sgibbs * target. 62413177Sgibbs */ 62513177Sgibbs mov FUNCTION1,SCB_TCL 6265326Sgibbs mov A,FUNCTION1 62713177Sgibbs test SCB_TCL,0x88 jz clear_a 6285326Sgibbs xor ACTIVE_B,A 62913177Sgibbs jmp test_immediate 6305326Sgibbs 6315326Sgibbsclear_a: 6325326Sgibbs xor ACTIVE_A,A 6335326Sgibbs 63413177Sgibbstest_immediate: 63513177Sgibbs test SCB_CMDLEN,0xff jnz complete /* Immediate message complete */ 63613177Sgibbs/* 63713177Sgibbs * Pause the sequencer until the driver gets around to handling the command 63813177Sgibbs * complete. This is so that any action that might require carefull timing 63913177Sgibbs * with the completion of this command can occur. 64013177Sgibbs */ 6419810Sgibbs mvi INTSTAT,IMMEDDONE 64213177Sgibbs jmp start 6435326Sgibbscomplete: 6444568Sgibbs mov QOUTFIFO,SCBPTR 6457532Sgibbs mvi INTSTAT,CMDCMPLT 6469954Sgibbs jmp mesgin_done 6474568Sgibbs 6487532Sgibbs 64913177Sgibbs/* 65013177Sgibbs * Is it an extended message? We only support the synchronous and wide data 65113177Sgibbs * transfer request messages, which will probably be in response to 65213177Sgibbs * WDTR or SDTR message outs from us. If it's not SDTR or WDTR, reject it - 65313177Sgibbs * apparently this can be done after any message in byte, according 65413177Sgibbs * to the SCSI-2 spec. 65513177Sgibbs */ 6569954Sgibbsmesgin_extended: 65713177Sgibbs mvi ARG_1 call inb_next /* extended message length */ 65813177Sgibbs mvi A call inb_next /* extended message code */ 6594568Sgibbs 66013177Sgibbs cmp A,MSG_SDTR je p_mesginSDTR 66113177Sgibbs cmp A,MSG_WDTR je p_mesginWDTR 6629954Sgibbs jmp rej_mesgin 6635562Sgibbs 6645562Sgibbsp_mesginWDTR: 66513177Sgibbs cmp ARG_1,2 jne rej_mesgin /* extended mesg length=2 */ 66613177Sgibbs mvi ARG_1 call inb_next /* Width of bus */ 66713177Sgibbs mvi INTSTAT,WDTR_MSG /* let driver know */ 66813177Sgibbs test RETURN_1,0xff jz mesgin_done /* Do we need to send WDTR? */ 66913177Sgibbs cmp RETURN_1,SEND_REJ je rej_mesgin /* 67013177Sgibbs * Bus width was too large 67113177Sgibbs * Reject it. 67213177Sgibbs */ 6735562Sgibbs 67413177Sgibbs/* We didn't initiate the wide negotiation, so we must respond to the request */ 67513177Sgibbs and RETURN_1,0x7f /* Clear the SEND_WDTR Flag */ 67613177Sgibbs mvi DINDEX,MSG0 67713177Sgibbs mvi MSG0 call mk_wdtr /* build WDTR message */ 67813177Sgibbs or SINDEX,0x10,SIGSTATE /* turn on ATNO */ 6795562Sgibbs call scsisig 6809954Sgibbs jmp mesgin_done 6815562Sgibbs 6825562Sgibbsp_mesginSDTR: 68313177Sgibbs cmp ARG_1,3 jne rej_mesgin /* extended mesg length=3 */ 68413177Sgibbs mvi ARG_1 call inb_next /* xfer period */ 68513177Sgibbs mvi A call inb_next /* REQ/ACK offset */ 68613177Sgibbs mvi INTSTAT,SDTR_MSG /* call driver to convert */ 6874568Sgibbs 68813177Sgibbs test RETURN_1,0xff jz mesgin_done /* Do we need to mk_sdtr/rej */ 68913177Sgibbs cmp RETURN_1,SEND_REJ je rej_mesgin /* 69013177Sgibbs * Requested SDTR too small 69113177Sgibbs * Reject it. 69213177Sgibbs */ 69313177Sgibbs mvi DINDEX, MSG0 69413177Sgibbs mvi MSG0 call mk_sdtr 69513177Sgibbs or SINDEX,0x10,SIGSTATE /* turn on ATNO */ 6965562Sgibbs call scsisig 6979954Sgibbs jmp mesgin_done 6984568Sgibbs 69913177Sgibbs/* 70013177Sgibbs * Is it a disconnect message? Set a flag in the SCB to remind us 70113177Sgibbs * and await the bus going free. 70213177Sgibbs */ 7039954Sgibbsmesgin_disconnect: 70413177Sgibbs or SCB_CONTROL,DISCONNECTED 7059954Sgibbs jmp mesgin_done 7064568Sgibbs 70713177Sgibbs/* 70813177Sgibbs * Save data pointers message? Copy working values into the SCB, 70913177Sgibbs * usually in preparation for a disconnect. 71013177Sgibbs */ 7119954Sgibbsmesgin_sdptrs: 7124568Sgibbs call sg_ram2scb 7139954Sgibbs jmp mesgin_done 7144568Sgibbs 71513177Sgibbs/* 71613177Sgibbs * Restore pointers message? Data pointers are recopied from the 71713177Sgibbs * SCB anytime we enter a data phase for the first time, so all 71813177Sgibbs * we need to do is clear the DPHASE flag and let the data phase 71913177Sgibbs * code do the rest. 72013177Sgibbs */ 7219954Sgibbsmesgin_rdptrs: 72213177Sgibbs and FLAGS,0xfb /* 72313177Sgibbs * !DPHASE we'll reload them 72413177Sgibbs * the next time through 72513177Sgibbs */ 7269954Sgibbs jmp mesgin_done 7274568Sgibbs 72813177Sgibbs/* 72913177Sgibbs * Identify message? For a reconnecting target, this tells us the lun 73013177Sgibbs * that the reconnection is for - find the correct SCB and switch to it, 73113177Sgibbs * clearing the "disconnected" bit so we don't "find" it by accident later. 73213177Sgibbs */ 7339954Sgibbsmesgin_identify: 73413177Sgibbs test A,0x78 jnz rej_mesgin /*!DiscPriv|!LUNTAR|!Reserved*/ 7354568Sgibbs 73613177Sgibbs and A,0x07 /* lun in lower three bits */ 7376608Sgibbs or SAVED_TCL,A,SELID 7386608Sgibbs and SAVED_TCL,0xf7 73913177Sgibbs and A,SELBUSB,SBLKCTL /* B Channel?? */ 7406608Sgibbs or SAVED_TCL,A 74113177Sgibbs call inb_last /* ACK */ 74213177Sgibbs 74313177Sgibbs/* 74413177Sgibbs * Here we "snoop" the bus looking for a SIMPLE QUEUE TAG message. 74513177Sgibbs * If we get one, we use the tag returned to switch to the proper 74613177Sgibbs * SCB. Otherwise, we just use the findSCB method. 74713177Sgibbs */ 74813177Sgibbssnoop_tag_loop: 74913177Sgibbs test SSTAT1,BUSFREE jnz use_findSCB 75013177Sgibbs test SSTAT1,REQINIT jz snoop_tag_loop 75113177Sgibbs test SSTAT1,PHASEMIS jnz use_findSCB 75213177Sgibbs mvi A call inb_first 75313177Sgibbs cmp A,MSG_SIMPLE_TAG je get_tag 75413177Sgibbsuse_findSCB: 75513177Sgibbs mov ALLZEROS call findSCB /* Have to search */ 7566608Sgibbssetup_SCB: 75713177Sgibbs and SCB_CONTROL,0xfb /* clear disconnect bit in SCB */ 75813177Sgibbs or FLAGS,IDENTIFY_SEEN /* make note of IDENTIFY */ 7596608Sgibbs jmp ITloop 7606608Sgibbsget_tag: 76113177Sgibbs mvi ARG_1 call inb_next /* tag value */ 76213177Sgibbs/* 76313177Sgibbs * See if the tag is in range. The tag is < SCBCOUNT if we add 76413177Sgibbs * the complement of SCBCOUNT to the incomming tag and there is 76513177Sgibbs * no carry. 76613177Sgibbs */ 76713177Sgibbs mov A,COMP_SCBCOUNT 76813177Sgibbs add SINDEX,A,ARG_1 76913177Sgibbs jc abort_tag 77013177Sgibbs 77113177Sgibbs/* 77213177Sgibbs * Ensure that the SCB the tag points to is for an SCB transaction 77313177Sgibbs * to the reconnecting target. 77413177Sgibbs */ 77513177Sgibbs mov SCBPTR,ARG_1 7766608Sgibbs mov A,SAVED_TCL 77713177Sgibbs cmp SCB_TCL,A jne abort_tag 77813177Sgibbs test SCB_CONTROL,TAG_ENB jz abort_tag 77913177Sgibbs call inb_last /* Ack Successful tag */ 78013177Sgibbs jmp setup_SCB 7817700Sgibbsabort_tag: 78213177Sgibbs or SINDEX,0x10,SIGSTATE /* turn on ATNO */ 7837700Sgibbs call scsisig 78413177Sgibbs mvi INTSTAT,ABORT_TAG /* let driver know */ 78513177Sgibbs mvi 0xd call mk_mesg /* ABORT TAG message */ 78613177Sgibbs jmp mesgin_done 7876608Sgibbs 78813177Sgibbs/* 78913177Sgibbs * Message reject? Let the kernel driver handle this. If we have an 79013177Sgibbs * outstanding WDTR or SDTR negotiation, assume that it's a response from 79113177Sgibbs * the target selecting 8bit or asynchronous transfer, otherwise just ignore 79213177Sgibbs * it since we have no clue what it pertains to. 79313177Sgibbs */ 7949954Sgibbsmesgin_reject: 79513177Sgibbs mvi INTSTAT, REJECT_MSG 7969954Sgibbs jmp mesgin_done 7975562Sgibbs 79813177Sgibbs/* 79913177Sgibbs * [ ADD MORE MESSAGE HANDLING HERE ] 80013177Sgibbs */ 8014568Sgibbs 80213177Sgibbs/* 80313177Sgibbs * Bus free phase. It might be useful to interrupt the device 80413177Sgibbs * driver if we aren't expecting this. For now, make sure that 80513177Sgibbs * ATN isn't being asserted and look for a new command. 80613177Sgibbs */ 8074568Sgibbsp_busfree: 80813177Sgibbs mvi CLRSINT1,CLRATNO 8098567Sdg 81013177Sgibbs/* 81113177Sgibbs * if this is an immediate command, perform a psuedo command complete to 81213177Sgibbs * notify the driver. 81313177Sgibbs */ 81413177Sgibbs test SCB_CMDLEN,0xff jz status_ok 81513177Sgibbs jmp start 8164568Sgibbs 81713177Sgibbs/* 81813177Sgibbs * Instead of a generic bcopy routine that requires an argument, we unroll 81913177Sgibbs * the cases that are actually used, and call them explicitly. This 82013177Sgibbs * not only reduces the overhead of doing a bcopy, but ends up saving space 82113177Sgibbs * in the program since you don't have to put the argument into the accumulator 82213177Sgibbs * before the call. Both functions expect DINDEX to contain the destination 82313177Sgibbs * address and SINDEX to contain the source address. 82413177Sgibbs */ 8259928Sgibbsbcopy_7: 8264568Sgibbs mov DINDIR,SINDIR 8275775Sgibbs mov DINDIR,SINDIR 8289928Sgibbsbcopy_5: 8299928Sgibbs mov DINDIR,SINDIR 8305775Sgibbsbcopy_4: 8315775Sgibbs mov DINDIR,SINDIR 8329928Sgibbsbcopy_3: 8335775Sgibbs mov DINDIR,SINDIR 8345775Sgibbs mov DINDIR,SINDIR 8355775Sgibbs mov DINDIR,SINDIR ret 8365775Sgibbs 8379928Sgibbsbcopy_7_dfdat: 8387532Sgibbs mov DINDIR,DFDAT 8397532Sgibbs mov DINDIR,DFDAT 8409928Sgibbsbcopy_5_dfdat: 8419928Sgibbs mov DINDIR,DFDAT 8427532Sgibbsbcopy_4_dfdat: 8437532Sgibbs mov DINDIR,DFDAT 8449928Sgibbsbcopy_3_dfdat: 8457532Sgibbs mov DINDIR,DFDAT 8467532Sgibbs mov DINDIR,DFDAT 8477532Sgibbs mov DINDIR,DFDAT ret 8487532Sgibbs 84913177Sgibbs/* 85013177Sgibbs * Locking the driver out, build a one-byte message passed in SINDEX 85113177Sgibbs * if there is no active message already. SINDEX is returned intact. 85213177Sgibbs */ 8534568Sgibbsmk_mesg: 85413177Sgibbs mvi SEQCTL,0x50 /* PAUSEDIS|FASTMODE */ 85513177Sgibbs test MSG_LEN,0xff jz mk_mesg1 /* Should always succeed */ 85613177Sgibbs 85713177Sgibbs /* 85813177Sgibbs * Hmmm. For some reason the mesg buffer is in use. 85913177Sgibbs * Tell the driver. It should look at SINDEX to find 86013177Sgibbs * out what we wanted to use the buffer for and resolve 86113177Sgibbs * the conflict. 86213177Sgibbs */ 86313177Sgibbs mvi SEQCTL,0x10 /* !PAUSEDIS|FASTMODE */ 86413177Sgibbs mvi INTSTAT,MSG_BUFFER_BUSY ret 8654568Sgibbs 8664568Sgibbsmk_mesg1: 86713177Sgibbs mvi MSG_LEN,1 /* length = 1 */ 86813177Sgibbs mov MSG0,SINDEX /* 1-byte message */ 86913177Sgibbs mvi SEQCTL,0x10 ret /* !PAUSEDIS|FASTMODE */ 8704568Sgibbs 87113177Sgibbs/* 87213177Sgibbs * Functions to read data in Automatic PIO mode. 87313177Sgibbs * 87413177Sgibbs * According to Adaptec's documentation, an ACK is not sent on input from 87513177Sgibbs * the target until SCSIDATL is read from. So we wait until SCSIDATL is 87613177Sgibbs * latched (the usual way), then read the data byte directly off the bus 87713177Sgibbs * using SCSIBUSL. When we have pulled the ATN line, or we just want to 87813177Sgibbs * acknowledge the byte, then we do a dummy read from SCISDATL. The SCSI 87913177Sgibbs * spec guarantees that the target will hold the data byte on the bus until 88013177Sgibbs * we send our ACK. 88113177Sgibbs * 88213177Sgibbs * The assumption here is that these are called in a particular sequence, 88313177Sgibbs * and that REQ is already set when inb_first is called. inb_{first,next} 88413177Sgibbs * use the same calling convention as inb. 88513177Sgibbs */ 88613177Sgibbs 88713177Sgibbsinb_next: 88813251Sgibbs call inb_last 88913313Sgibbsinb_first: 89013251Sgibbs test SSTAT1,PHASEMIS jnz mesgin_phasemis 89113313Sgibbs test SSTAT0,SPIORDY jz inb_first /* wait for next byte */ 8924568Sgibbs mov DINDEX,SINDEX 89313177Sgibbs mov DINDIR,SCSIBUSL ret /*read byte directly from bus*/ 89413177Sgibbsinb_last: 89513313Sgibbs or SXFRCTL0,CLRSTCNT 89613251Sgibbs mvi STCNT0,0x01 89713251Sgibbs mov NONE,SCSIDATL /*dummy read from latch to ACK*/ 89813251Sgibbsinb_last_wait: 89913251Sgibbs test SSTAT0,SDONE jz inb_last_wait /* Wait for completion */ 90013251Sgibbs ret 9014568Sgibbs 90213177Sgibbsmesgin_phasemis: 90313177Sgibbs/* 90413177Sgibbs * We expected to receive another byte, but the target changed phase 90513177Sgibbs */ 90613177Sgibbs mvi INTSTAT, MSGIN_PHASEMIS 90713177Sgibbs jmp ITloop 9084568Sgibbs 90913177Sgibbs/* 91013177Sgibbs * DMA data transfer. HADDR and HCNT must be loaded first, and 91113177Sgibbs * SINDEX should contain the value to load DFCNTRL with - 0x3d for 91213177Sgibbs * host->scsi, or 0x39 for scsi->host. The SCSI channel is cleared 91313177Sgibbs * during initialization. 91413177Sgibbs */ 9154568Sgibbsdma: 9164568Sgibbs mov DFCNTRL,SINDEX 9174568Sgibbsdma1: 91813177Sgibbs test SSTAT0,DMADONE jnz dma3 91913177Sgibbs test SSTAT1,PHASEMIS jz dma1 /* ie. underrun */ 9204568Sgibbs 92113177Sgibbs/* 92213177Sgibbs * We will be "done" DMAing when the transfer count goes to zero, or 92313177Sgibbs * the target changes the phase (in light of this, it makes sense that 92413177Sgibbs * the DMA circuitry doesn't ACK when PHASEMIS is active). If we are 92513177Sgibbs * doing a SCSI->Host transfer, the data FIFO should be flushed auto- 92613177Sgibbs * magically on STCNT=0 or a phase change, so just wait for FIFO empty 92713177Sgibbs * status. 92813177Sgibbs */ 9294568Sgibbsdma3: 93013177Sgibbs test SINDEX,DIRECTION jnz dma5 9314568Sgibbsdma4: 93213177Sgibbs test DFSTATUS,FIFOEMP jz dma4 9334568Sgibbs 93413177Sgibbs/* 93513177Sgibbs * Now shut the DMA enables off and make sure that the DMA enables are 93613177Sgibbs * actually off first lest we get an ILLSADDR. 93713177Sgibbs */ 9384568Sgibbsdma5: 93913177Sgibbs /* disable DMA, but maintain WIDEODD */ 94013177Sgibbs and A, WIDEODD, SINDEX 94113177Sgibbs mov DFCNTRL, A 9424568Sgibbsdma6: 94313177Sgibbs test DFCNTRL,0x38 jnz dma6 /* SCSIENACK|SDMAENACK|HDMAENACK */ 9444568Sgibbs 9454568Sgibbs ret 9464568Sgibbs 9477532Sgibbsdma_finish: 94813177Sgibbs test DFSTATUS,HDONE jz dma_finish 9497532Sgibbs 95013177Sgibbs clr DFCNTRL /* disable DMA */ 9517532Sgibbsdma_finish2: 95213177Sgibbs test DFCNTRL,HDMAENACK jnz dma_finish2 9537532Sgibbs ret 9547532Sgibbs 95513177Sgibbs/* 95613177Sgibbs * Common SCSI initialization for selection and reselection. Expects 95713177Sgibbs * the target SCSI ID to be in the upper four bits of SINDEX, and A's 95813177Sgibbs * contents are stomped on return. 95913177Sgibbs */ 9608104Sgibbsinitialize_scsiid: 96113177Sgibbs and SINDEX,0xf0 /* Get target ID */ 9625775Sgibbs and A,0x0f,SCSIID 9635775Sgibbs or SINDEX,A 9648104Sgibbs mov SCSIID,SINDEX ret 9655326Sgibbs 96613177Sgibbs/* 96713177Sgibbs * Assert that if we've been reselected, then we've seen an IDENTIFY 96813177Sgibbs * message. 96913177Sgibbs */ 9704568Sgibbsassert: 97113177Sgibbs test FLAGS,RESELECTED jz return /* reselected? */ 97213177Sgibbs test FLAGS,IDENTIFY_SEEN jnz return /* seen IDENTIFY? */ 9734568Sgibbs 97413177Sgibbs mvi INTSTAT,NO_IDENT ret /* no - cause a kernel panic */ 9754568Sgibbs 97613177Sgibbs/* 97713177Sgibbs * Locate the SCB matching the target ID/channel/lun in SAVED_TCL and switch 97813177Sgibbs * the SCB to it. Have the kernel print a warning message if it can't be 97913177Sgibbs * found, and generate an ABORT message to the target. SINDEX should be 98013177Sgibbs * cleared on call. 98113177Sgibbs */ 9824568SgibbsfindSCB: 9836608Sgibbs mov A,SAVED_TCL 98413177Sgibbs mov SCBPTR,SINDEX /* switch to new SCB */ 98513177Sgibbs cmp SCB_TCL,A jne findSCB1 /* target ID/channel/lun match? */ 98613177Sgibbs test SCB_CONTROL,DISCONNECTED jz findSCB1 /*should be disconnected*/ 9874568Sgibbs ret 9884568Sgibbs 9896608SgibbsfindSCB1: 9904568Sgibbs inc SINDEX 9914568Sgibbs mov A,SCBCOUNT 9926608Sgibbs cmp SINDEX,A jne findSCB 9934568Sgibbs 99413177Sgibbs mvi INTSTAT,NO_MATCH /* not found - signal kernel */ 99513177Sgibbs mvi MSG_ABORT call mk_mesg /* ABORT message */ 9964568Sgibbs 99713177Sgibbs or SINDEX,0x10,SIGSTATE /* assert ATNO */ 9984568Sgibbs call scsisig 9994568Sgibbs ret 100013177Sgibbs/* 100113177Sgibbs * Make a working copy of the scatter-gather parameters from the SCB. 100213177Sgibbs */ 10034568Sgibbssg_scb2ram: 10049928Sgibbs mvi DINDEX,HADDR 100513177Sgibbs mvi SCB_DATAPTR call bcopy_7 10069928Sgibbs 10079928Sgibbs mvi DINDEX,STCNT 100813177Sgibbs mvi SCB_DATACNT call bcopy_3 10099928Sgibbs 101013177Sgibbs mov SG_COUNT,SCB_SGCOUNT 10114568Sgibbs 10124568Sgibbs mvi DINDEX,SG_NEXT 101313177Sgibbs mvi SCB_SGPTR call bcopy_4 10149928Sgibbs ret 10154568Sgibbs 101613177Sgibbs/* 101713177Sgibbs * Copying RAM values back to SCB, for Save Data Pointers message, but 101813177Sgibbs * only if we've actually been into a data phase to change them. This 101913177Sgibbs * protects against bogus data in scratch ram and the residual counts 102013177Sgibbs * since they are only initialized when we go into data_in or data_out. 102113177Sgibbs */ 10224568Sgibbssg_ram2scb: 10239928Sgibbs test FLAGS, DPHASE jz return 102413177Sgibbs mov SCB_SGCOUNT,SG_COUNT 10254568Sgibbs 102613177Sgibbs mvi DINDEX,SCB_SGPTR 10275775Sgibbs mvi SG_NEXT call bcopy_4 10289928Sgibbs 102913177Sgibbs mvi DINDEX,SCB_DATAPTR 10309928Sgibbs mvi SHADDR call bcopy_4 10314568Sgibbs 103213177Sgibbs/* 103313177Sgibbs * Use the residual number since STCNT is corrupted by any message transfer 103413177Sgibbs */ 103513177Sgibbs mvi SCB_RESID_DCNT call bcopy_3 10364568Sgibbs ret 10374568Sgibbs 103813177Sgibbs/* 103913177Sgibbs * Add the array base TARG_SCRATCH to the target offset (the target address 104013177Sgibbs * is in SCSIID), and return the result in SINDEX. The accumulator 104113177Sgibbs * contains the 3->8 decoding of the target ID on return. 104213177Sgibbs */ 10435562Sgibbsndx_dtr: 10444568Sgibbs shr A,SCSIID,4 104513177Sgibbs test SBLKCTL,SELBUSB jz ndx_dtr_2 104613177Sgibbs or A,0x08 /* Channel B entries add 8 */ 10475562Sgibbsndx_dtr_2: 104813177Sgibbs add SINDEX,TARG_SCRATCH,A 10494568Sgibbs 105013177Sgibbs mov FUNCTION1,SCSIID /* 3-bit target address decode */ 10514568Sgibbs mov A,FUNCTION1 ret 10524568Sgibbs 105313177Sgibbs/* 105413177Sgibbs * If we need to negotiate transfer parameters, build the WDTR or SDTR message 105513177Sgibbs * starting at the address passed in SINDEX. DINDEX is modified on return. 105613177Sgibbs * The SCSI-II spec requires that Wide negotiation occur first and you can 105713177Sgibbs * only negotiat one or the other at a time otherwise in the event of a message 105813177Sgibbs * reject, you wouldn't be able to tell which message was the culpret. 105913177Sgibbs */ 10605562Sgibbsmk_dtr: 106113177Sgibbs test SCB_CONTROL,0x90 jz return /* NEEDWDTR|NEEDSDTR */ 106213177Sgibbs test SCB_CONTROL,NEEDWDTR jnz mk_wdtr_16bit 106313177Sgibbs or FLAGS, MAXOFFSET /* Force an offset of 15 or 8 if WIDE */ 10644568Sgibbs 10657532Sgibbsmk_sdtr: 106613177Sgibbs mvi DINDIR,1 /* extended message */ 106713177Sgibbs mvi DINDIR,3 /* extended message length = 3 */ 106813177Sgibbs mvi DINDIR,1 /* SDTR code */ 10697532Sgibbs call sdtr_to_rate 107013177Sgibbs mov DINDIR,RETURN_1 /* REQ/ACK transfer period */ 107113177Sgibbs test FLAGS, MAXOFFSET jnz mk_sdtr_max_offset 107213177Sgibbs and DINDIR,0x0f,SINDIR /* Sync Offset */ 10737532Sgibbs 10747532Sgibbsmk_sdtr_done: 107513177Sgibbs add MSG_LEN,COMP_MSG0,DINDEX ret /* update message length */ 10767532Sgibbs 10778567Sdgmk_sdtr_max_offset: 107813177Sgibbs/* 107913177Sgibbs * We're initiating sync negotiation, so request the max offset we can (15 or 8) 108013177Sgibbs */ 108113177Sgibbs xor FLAGS, MAXOFFSET 108213177Sgibbs 108313177Sgibbs /* Talking to a WIDE device? */ 108413177Sgibbs test SCSIRATE, WIDEXFER jnz wmax_offset 10858567Sdg mvi DINDIR, MAX_OFFSET_8BIT 10867532Sgibbs jmp mk_sdtr_done 10877532Sgibbs 10888567Sdgwmax_offset: 108913177Sgibbs mvi DINDIR, MAX_OFFSET_16BIT 10908567Sdg jmp mk_sdtr_done 10918567Sdg 10925647Sgibbsmk_wdtr_16bit: 10935647Sgibbs mvi ARG_1,BUS_16_BIT 10945562Sgibbsmk_wdtr: 109513177Sgibbs mvi DINDIR,1 /* extended message */ 109613177Sgibbs mvi DINDIR,2 /* extended message length = 2 */ 109713177Sgibbs mvi DINDIR,3 /* WDTR code */ 109813177Sgibbs mov DINDIR,ARG_1 /* bus width */ 10995562Sgibbs 110013177Sgibbs add MSG_LEN,COMP_MSG0,DINDEX ret /* update message length */ 11015562Sgibbs 110213177Sgibbs/* 110313177Sgibbs * Set SCSI bus control signal state. This also saves the last-written 110413177Sgibbs * value into a location where the higher-level driver can read it - if 110513177Sgibbs * it has to send an ABORT or RESET message, then it needs to know this 110613177Sgibbs * so it can assert ATN without upsetting SCSISIGO. The new value is 110713177Sgibbs * expected in SINDEX. Change the actual state last to avoid contention 110813177Sgibbs * from the driver. 110913177Sgibbs */ 11104568Sgibbsscsisig: 11114568Sgibbs mov SIGSTATE,SINDEX 11124568Sgibbs mov SCSISIGO,SINDEX ret 11135562Sgibbs 11145562Sgibbssdtr_to_rate: 111513177Sgibbs call ndx_dtr /* index scratch space for target */ 11165562Sgibbs shr A,SINDIR,0x4 111713177Sgibbs dec SINDEX /* Preserve SINDEX */ 11185562Sgibbs and A,0x7 11195562Sgibbs clr RETURN_1 11205562Sgibbssdtr_to_rate_loop: 11215562Sgibbs test A,0x0f jz sdtr_to_rate_done 112213177Sgibbs add RETURN_1,0x19 11235562Sgibbs dec A 11245562Sgibbs jmp sdtr_to_rate_loop 11255562Sgibbssdtr_to_rate_done: 11265562Sgibbs shr RETURN_1,0x2 112713177Sgibbs add RETURN_1,0x19 112811829Sgibbs test SXFRCTL0,ULTRAEN jz return 112911829Sgibbs shr RETURN_1,0x1 11307532Sgibbsreturn: 11317532Sgibbs ret 1132