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Diffstat (limited to 'drivers/scsi/aic7xxx.seq')
| -rw-r--r-- | drivers/scsi/aic7xxx.seq | 1127 |
1 files changed, 0 insertions, 1127 deletions
diff --git a/drivers/scsi/aic7xxx.seq b/drivers/scsi/aic7xxx.seq index 98d4b9545..e69de29bb 100644 --- a/drivers/scsi/aic7xxx.seq +++ b/drivers/scsi/aic7xxx.seq @@ -1,1127 +0,0 @@ -/*+M************************************************************************* - * Adaptec AIC7xxx device driver for Linux and FreeBSD. - * - * Copyright (c) 1994 John Aycock - * The University of Calgary Department of Computer Science. - * - *Modifications/enhancements: - * Copyright (c) 1994, 1995, 1996 Justin Gibbs. All rights reserved. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2, or (at your option) - * any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; see the file COPYING. If not, write to - * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. - * - * FreeBSD, Twin, Wide, 2 command per target support, tagged queuing and other - * optimizations provided by Justin T. Gibbs (gibbs@FreeBSD.org) - * - * This version corresponds to version 1.42 of FreeBSDs aic7xxx.seq. - * - *-M*************************************************************************/ - -VERSION AIC7XXX_SEQ_VER "$Id: aic7xxx.seq,v 4.0 1996/10/13 08:23:42 deang Exp $" - -#ifdef linux -#include "aic7xxx_reg.h" -#else -#if defined(__NetBSD__) -#include "../../../../dev/ic/aic7xxxreg.h" -#elif defined(__FreeBSD__) -#include "../../dev/aic7xxx/aic7xxx_reg.h" -#endif -#endif - -/* - * We can't just use ACCUM in the sequencer code because it - * must be treated specially by the assembler, and it currently - * looks for the symbol 'A'. This is the only register defined in - * the assembler's symbol space. - */ -A = ACCUM - -/* After starting the selection hardware, we check for reconnecting targets - * as well as for our selection to complete just in case the reselection wins - * bus arbitration. The problem with this is that we must keep track of the - * SCB that we've already pulled from the QINFIFO and started the selection - * on just in case the reselection wins so that we can retry the selection at - * a later time. This problem cannot be resolved by holding a single entry - * in scratch ram since a reconnecting target can request sense and this will - * create yet another SCB waiting for selection. The solution used here is to - * use byte 27 of the SCB as a pseudo-next pointer and to thread a list - * of SCBs that are awaiting selection. Since 0-0xfe are valid SCB offsets, - * SCB_LIST_NULL is 0xff which is out of range. The kernel driver must - * add an entry to this list every time a request sense occurs. The sequencer - * will automatically consume the entries. - */ - -/* - * We assume that the kernel driver may reset us at any time, even in the - * middle of a DMA, so clear DFCNTRL too. - */ -reset: - clr DFCNTRL - clr SCSISIGO /* De-assert BSY */ -/* - * We jump to start after every bus free. - */ -start: - and FLAGS,0x0f /* clear target specific flags */ - mvi SCSISEQ,ENRSELI /* Always allow reselection */ - clr SCSIRATE /* - * We don't know the target we will - * connect to, so default to narrow - * transfers to avoid parity problems. - */ -poll_for_work: - /* - * Are we a twin channel device? - * For fairness, we check the other bus first, - * since we just finished a transaction on the - * current channel. - */ - test FLAGS,TWIN_BUS jz start2 - xor SBLKCTL,SELBUSB /* Toggle to the other bus */ - test SSTAT0,SELDI jnz reselect - xor SBLKCTL,SELBUSB /* Toggle to the original bus */ -start2: - test SSTAT0,SELDI jnz reselect - cmp WAITING_SCBH,SCB_LIST_NULL jne start_waiting - mov A, QCNTMASK - test QINCNT,A jz poll_for_work - -/* - * We have at least one queued SCB now and we don't have any - * SCBs in the list of SCBs awaiting selection. Set the SCB - * pointer from the FIFO so we see the right bank of SCB - * registers. - */ - mov SCBPTR,QINFIFO - -/* - * See if there is not already an active SCB for this target. This code - * locks out on a per target basis instead of target/lun. Although this - * is not ideal for devices that have multiple luns active at the same - * time, it is faster than looping through all SCB's looking for active - * commands. It may be beneficial to make findscb a more general procedure - * to see if the added cost of the search is negligible. This code also - * assumes that the kernel driver will clear the active flags on board - * initialization, board reset, and a target SELTO. Tagged commands - * don't set the active bits since you can queue more than one command - * at a time. We do, however, look to see if there are any non-tagged - * I/Os in progress, and requeue the command if there are. Tagged and - * non-tagged commands cannot be mixed to a single target. - */ - -test_busy: - mov FUNCTION1,SCB_TCL - mov A,FUNCTION1 - test SCB_TCL,0x88 jz test_a /* Id < 8 && A channel */ - - test ACTIVE_B,A jnz requeue - test SCB_CONTROL,TAG_ENB jnz start_scb - /* Mark the current target as busy */ - or ACTIVE_B,A - jmp start_scb - -/* Place the currently active SCB back on the queue for later processing */ -requeue: - mov QINFIFO, SCBPTR - jmp poll_for_work - -/* - * Pull the first entry off of the waiting for selection list - * We don't have to "test_busy" because only transactions that - * have passed that test can be in the waiting_scb list. - */ -start_waiting: - mov SCBPTR,WAITING_SCBH - jmp start_scb2 - -test_a: - test ACTIVE_A,A jnz requeue - test SCB_CONTROL,TAG_ENB jnz start_scb - /* Mark the current target as busy */ - or ACTIVE_A,A - -start_scb: - mov SCB_NEXT,WAITING_SCBH - mov WAITING_SCBH, SCBPTR -start_scb2: - and SINDEX,0xf7,SBLKCTL /* Clear the channel select bit */ - and A,0x08,SCB_TCL /* Get new channel bit */ - or SINDEX,A - mov SBLKCTL,SINDEX /* select channel */ - mov SCB_TCL call initialize_scsiid - -/* - * Enable selection phase as an initiator, and do automatic ATN - * after the selection. We do this now so that we can overlap the - * rest of our work to set up this target with the arbitration and - * selection bus phases. - */ -start_selection: - mvi SCSISEQ,0x58 /* ENSELO|ENAUTOATNO|ENRSELI */ - -/* - * As soon as we get a successful selection, the target should go - * into the message out phase since we have ATN asserted. Prepare - * the message to send. - * - * Messages are stored in scratch RAM starting with a length byte - * followed by the message itself. - */ - test SCB_CMDLEN,0xff jnz mk_identify /* 0 Length Command? */ - -/* - * The kernel has sent us an SCB with no command attached. This implies - * that the kernel wants to send a message of some sort to this target, - * so we interrupt the driver, allow it to fill the message buffer, and - * then go back into the arbitration loop - */ - mvi INTSTAT,AWAITING_MSG - jmp wait_for_selection - -mk_identify: - and A,DISCENB,SCB_CONTROL /* mask off disconnect privledge */ - - and MSG0,0x7,SCB_TCL /* lun */ - or MSG0,A /* or in disconnect privledge */ - or MSG0,MSG_IDENTIFY - mvi MSG_LEN, 1 - - test SCB_CONTROL,0xb0 jz !message /* WDTR, SDTR or TAG?? */ -/* - * Send a tag message if TAG_ENB is set in the SCB control block. - * Use SCB_TAG (the position in the kernel's SCB array) as the tag value. - */ - -mk_tag: - mvi DINDEX, MSG1 - test SCB_CONTROL,TAG_ENB jz mk_tag_done - and DINDIR,0x23,SCB_CONTROL - mov DINDIR,SCB_TAG - - add MSG_LEN,COMP_MSG0,DINDEX /* update message length */ - -mk_tag_done: - - test SCB_CONTROL,0x90 jz !message /* NEEDWDTR|NEEDSDTR */ - mov DINDEX call mk_dtr /* build DTR message if needed */ - -!message: -wait_for_selection: - test SSTAT0,SELDO jnz select - test SSTAT0,SELDI jz wait_for_selection - -/* - * Reselection has been initiated by a target. Make a note that we've been - * reselected, but haven't seen an IDENTIFY message from the target - * yet. - */ -reselect: - clr MSG_LEN /* Don't have anything in the mesg buffer */ - mov SELID call initialize_scsiid - or FLAGS,RESELECTED - jmp select2 - -/* - * After the selection, remove this SCB from the "waiting for selection" - * list. This is achieved by simply moving our "next" pointer into - * WAITING_SCBH. Our next pointer will be set to null the next time this - * SCB is used, so don't bother with it now. - */ -select: - mov WAITING_SCBH,SCB_NEXT - or FLAGS,SELECTED -select2: -/* - * Set CLRCHN here before the target has entered a data transfer mode - - * with synchronous SCSI, if you do it later, you blow away some - * data in the SCSI FIFO that the target has already sent to you. - */ - or SXFRCTL0,CLRCHN -/* - * Initialize SCSIRATE with the appropriate value for this target. - */ - call ndx_dtr - mov SCSIRATE,SINDIR - -/* - * Initialize Ultra mode setting. - */ - mov FUNCTION1,SCSIID - mov A,FUNCTION1 - and SINDEX,0xdf,SXFRCTL0 /* default to Ultra disabled */ - test SCSIID, 0x80 jnz ultra_b /* Target ID > 7 */ - test SBLKCTL, SELBUSB jnz ultra_b /* Second channel device */ - test ULTRA_ENB,A jz set_sxfrctl0 - or SINDEX, ULTRAEN jmp set_sxfrctl0 -ultra_b: - test ULTRA_ENB_B,A jz set_sxfrctl0 - or SINDEX, ULTRAEN - -set_sxfrctl0: - mov SXFRCTL0,SINDEX - - mvi SCSISEQ,ENAUTOATNP /* - * ATN on parity errors - * for "in" phases - */ - mvi CLRSINT1,CLRBUSFREE - mvi CLRSINT0,0x60 /* CLRSELDI|CLRSELDO */ -/* - * Main loop for information transfer phases. If BSY is false, then - * we have a bus free condition, expected or not. Otherwise, wait - * for the target to assert REQ before checking MSG, C/D and I/O - * for the bus phase. - * - */ -ITloop: - test SSTAT1,BUSFREE jnz p_busfree - test SSTAT1,REQINIT jz ITloop - - and A,PHASE_MASK,SCSISIGI - mov LASTPHASE,A - mov SCSISIGO,A - - cmp ALLZEROS,A je p_dataout - cmp A,P_DATAIN je p_datain - cmp A,P_COMMAND je p_command - cmp A,P_MESGOUT je p_mesgout - cmp A,P_STATUS je p_status - cmp A,P_MESGIN je p_mesgin - - mvi INTSTAT,BAD_PHASE /* unknown phase - signal driver */ - jmp ITloop /* Try reading the bus again. */ - -p_dataout: - mvi DMAPARAMS,0x7d /* - * WIDEODD|SCSIEN|SDMAEN|HDMAEN| - * DIRECTION|FIFORESET - */ - jmp data_phase_init - -/* - * If we re-enter the data phase after going through another phase, the - * STCNT may have been cleared, so restore it from the residual field. - */ -data_phase_reinit: - mov STCNT0,SCB_RESID_DCNT0 - mov STCNT1,SCB_RESID_DCNT1 - mov STCNT2,SCB_RESID_DCNT2 - jmp data_phase_loop - -p_datain: - mvi DMAPARAMS,0x79 /* - * WIDEODD|SCSIEN|SDMAEN|HDMAEN| - * !DIRECTION|FIFORESET - */ -data_phase_init: - call assert - - test FLAGS, DPHASE jnz data_phase_reinit - call sg_scb2ram - or FLAGS, DPHASE /* We have seen a data phase */ - -data_phase_loop: -/* Guard against overruns */ - test SG_COUNT, 0xff jnz data_phase_inbounds -/* - * Turn on 'Bit Bucket' mode, set the transfer count to - * 16meg and let the target run until it changes phase. - * When the transfer completes, notify the host that we - * had an overrun. - */ - or SXFRCTL1,BITBUCKET - mvi STCNT0,0xff - mvi STCNT1,0xff - mvi STCNT2,0xff - -data_phase_inbounds: -/* If we are the last SG block, don't set wideodd. */ - cmp SG_COUNT,0x01 jne data_phase_wideodd - and DMAPARAMS, 0xbf /* Turn off WIDEODD */ -data_phase_wideodd: - mov DMAPARAMS call dma - -/* Go tell the host about any overruns */ - test SXFRCTL1,BITBUCKET jnz data_phase_overrun - -/* Exit if we had an underrun */ - test SSTAT0,SDONE jz data_phase_finish /* underrun STCNT != 0 */ - -/* - * Advance the scatter-gather pointers if needed - */ -sg_advance: - dec SG_COUNT /* one less segment to go */ - - test SG_COUNT, 0xff jz data_phase_finish /* Are we done? */ - - clr A /* add sizeof(struct scatter) */ - add SG_NEXT0,SG_SIZEOF,SG_NEXT0 - adc SG_NEXT1,A,SG_NEXT1 - -/* - * Load a struct scatter and set up the data address and length. - * If the working value of the SG count is nonzero, then - * we need to load a new set of values. - * - * This, like all DMA's, assumes a little-endian host data storage. - */ -sg_load: - clr HCNT2 - clr HCNT1 - mvi HCNT0,SG_SIZEOF - - mov HADDR0,SG_NEXT0 - mov HADDR1,SG_NEXT1 - mov HADDR2,SG_NEXT2 - mov HADDR3,SG_NEXT3 - - or DFCNTRL,0xd /* HDMAEN|DIRECTION|FIFORESET */ - -/* - * Wait for DMA from host memory to data FIFO to complete, then disable - * DMA and wait for it to acknowledge that it's off. - */ -dma_finish: - test DFSTATUS,HDONE jz dma_finish - /* Turn off DMA preserving WIDEODD */ - and DFCNTRL,WIDEODD -dma_finish2: - test DFCNTRL,HDMAENACK jnz dma_finish2 - -/* - * Copy data from FIFO into SCB data pointer and data count. In - * both FreeBSD and Linux, the scatter list entry is 8 bytes. - * - * struct ahc_dma_seg { - * physaddr addr; four bytes, little-endian order - * long len; four bytes, little endian order - * }; - */ - - mov HADDR0,DFDAT - mov HADDR1,DFDAT - mov HADDR2,DFDAT - mov HADDR3,DFDAT - mov HCNT0,DFDAT - mov HCNT1,DFDAT - mov HCNT2,DFDAT - -/* Load STCNT as well. It is a mirror of HCNT */ - mov STCNT0,HCNT0 - mov STCNT1,HCNT1 - mov STCNT2,HCNT2 - test SSTAT1,PHASEMIS jz data_phase_loop - -data_phase_finish: -/* - * After a DMA finishes, save the SG and STCNT residuals back into the SCB - * We use STCNT instead of HCNT, since it's a reflection of how many bytes - * were transferred on the SCSI (as opposed to the host) bus. - */ - mov SCB_RESID_DCNT0,STCNT0 - mov SCB_RESID_DCNT1,STCNT1 - mov SCB_RESID_DCNT2,STCNT2 - mov SCB_RESID_SGCNT, SG_COUNT - jmp ITloop - -data_phase_overrun: -/* - * Turn off BITBUCKET mode and notify the host - */ - and SXFRCTL1,0x7f /* ~BITBUCKET */ - mvi INTSTAT,DATA_OVERRUN - jmp ITloop - -/* - * Command phase. Set up the DMA registers and let 'er rip. - */ -p_command: - call assert - -/* - * Load HADDR and HCNT. - */ - mov HADDR0, SCB_CMDPTR0 - mov HADDR1, SCB_CMDPTR1 - mov HADDR2, SCB_CMDPTR2 - mov HADDR3, SCB_CMDPTR3 - mov HCNT0, SCB_CMDLEN - clr HCNT1 - clr HCNT2 - - mov STCNT0, HCNT0 - mov STCNT1, HCNT1 - mov STCNT2, HCNT2 - - mvi 0x3d call dma # SCSIEN|SDMAEN|HDMAEN| - # DIRECTION|FIFORESET - jmp ITloop - -/* - * Status phase. Wait for the data byte to appear, then read it - * and store it into the SCB. - */ -p_status: - mvi SCB_TARGET_STATUS call inb_first - jmp mesgin_done - -/* - * Message out phase. If there is not an active message, but the target - * took us into this phase anyway, build a no-op message and send it. - */ -p_mesgout: - test MSG_LEN, 0xff jnz p_mesgout_start - mvi MSG_NOP call mk_mesg /* build NOP message */ - -p_mesgout_start: -/* - * Set up automatic PIO transfer from MSG0. Bit 3 in - * SXFRCTL0 (SPIOEN) is already on. - */ - mvi SINDEX,MSG0 - mov DINDEX,MSG_LEN - -/* - * When target asks for a byte, drop ATN if it's the last one in - * the message. Otherwise, keep going until the message is exhausted. - * - * Keep an eye out for a phase change, in case the target issues - * a MESSAGE REJECT. - */ -p_mesgout_loop: - test SSTAT1,PHASEMIS jnz p_mesgout_phasemis - test SSTAT0,SPIORDY jz p_mesgout_loop - test SSTAT1,PHASEMIS jnz p_mesgout_phasemis - cmp DINDEX,1 jne p_mesgout_outb /* last byte? */ - mvi CLRSINT1,CLRATNO /* drop ATN */ -p_mesgout_outb: - dec DINDEX - or CLRSINT0, CLRSPIORDY - mov SCSIDATL,SINDIR - -p_mesgout4: - test DINDEX,0xff jnz p_mesgout_loop - -/* - * If the next bus phase after ATN drops is a message out, it means - * that the target is requesting that the last message(s) be resent. - */ -p_mesgout_snoop: - test SSTAT1,BUSFREE jnz p_mesgout_done - test SSTAT1,REQINIT jz p_mesgout_snoop - - test SSTAT1,PHASEMIS jnz p_mesgout_done - - or SCSISIGO,ATNO /* turn on ATNO */ - - jmp ITloop - -p_mesgout_phasemis: - mvi CLRSINT1,CLRATNO /* Be sure to turn ATNO off */ -p_mesgout_done: - clr MSG_LEN /* no active msg */ - jmp ITloop - -/* - * Message in phase. Bytes are read using Automatic PIO mode. - */ -p_mesgin: - mvi A call inb_first /* read the 1st message byte */ - mov REJBYTE,A /* save it for the driver */ - - test A,MSG_IDENTIFY jnz mesgin_identify - cmp A,MSG_DISCONNECT je mesgin_disconnect - cmp A,MSG_SDPTRS je mesgin_sdptrs - cmp ALLZEROS,A je mesgin_complete - cmp A,MSG_RDPTRS je mesgin_rdptrs - cmp A,MSG_EXTENDED je mesgin_extended - cmp A,MSG_REJECT je mesgin_reject - -rej_mesgin: -/* - * We have no idea what this message in is, and there's no way - * to pass it up to the kernel, so we issue a message reject and - * hope for the best. Since we're now using manual PIO mode to - * read in the message, there should no longer be a race condition - * present when we assert ATN. In any case, rejection should be a - * rare occurrence - signal the driver when it happens. - */ - or SCSISIGO,ATNO /* turn on ATNO */ - mvi INTSTAT,SEND_REJECT /* let driver know */ - - mvi MSG_REJECT call mk_mesg - -mesgin_done: - call inb_last /*ack & turn auto PIO back on*/ - jmp ITloop - - -mesgin_complete: -/* - * We got a "command complete" message, so put the SCB_TAG into QUEUEOUT, - * and trigger a completion interrupt. Check status for non zero return - * and interrupt driver if needed. This allows the driver to interpret - * errors only when they occur instead of always uploading the scb. If - * the status is SCSI_CHECK, the driver will download a new scb requesting - * sense to replace the old one, modify the "waiting for selection" SCB list - * and set RETURN_1 to SEND_SENSE. If RETURN_1 is set to SEND_SENSE the - * sequencer imediately jumps to main loop where it will run down the waiting - * SCB list and process the sense request. If the kernel driver does not - * wish to request sense, it need only clear RETURN_1, and the command is - * allowed to complete. We don't bother to post to the QOUTFIFO in the - * error case since it would require extra work in the kernel driver to - * ensure that the entry was removed before the command complete code tried - * processing it. - * - * First check for residuals - */ - test SCB_RESID_SGCNT,0xff jz check_status -/* - * If we have a residual count, interrupt and tell the host. Other - * alternatives are to pause the sequencer on all command completes (yuck), - * dma the resid directly to the host (slick, we may have space to do it now) - * or have the sequencer pause itself when it encounters a non-zero resid - * (unnecessary pause just to flag the command -yuck-, but takes one instruction - * and since it shouldn't happen that often is good enough for our purposes). - */ -resid: - mvi INTSTAT,RESIDUAL - -check_status: - test SCB_TARGET_STATUS,0xff jz status_ok /* Good Status? */ - mvi INTSTAT,BAD_STATUS /* let driver know */ - cmp RETURN_1, SEND_SENSE jne status_ok - jmp mesgin_done - -status_ok: -/* First, mark this target as free. */ - test SCB_CONTROL,TAG_ENB jnz test_immediate /* - * Tagged commands - * don't busy the - * target. - */ - mov FUNCTION1,SCB_TCL - mov A,FUNCTION1 - test SCB_TCL,0x88 jz clear_a - xor ACTIVE_B,A - jmp test_immediate - -clear_a: - xor ACTIVE_A,A - -test_immediate: - test SCB_CMDLEN,0xff jnz complete /* Immediate message complete */ -/* - * Pause the sequencer until the driver gets around to handling the command - * complete. This is so that any action that might require careful timing - * with the completion of this command can occur. - */ - mvi INTSTAT,IMMEDDONE - jmp start -complete: - mov QOUTFIFO,SCB_TAG - mvi INTSTAT,CMDCMPLT - jmp mesgin_done - - -/* - * Is it an extended message? We only support the synchronous and wide data - * transfer request messages, which will probably be in response to - * WDTR or SDTR message outs from us. If it's not SDTR or WDTR, reject it - - * apparently this can be done after any message in byte, according - * to the SCSI-2 spec. - */ -mesgin_extended: - mvi ARG_1 call inb_next /* extended message length */ - mvi REJBYTE_EXT call inb_next /* extended message code */ - - cmp REJBYTE_EXT,MSG_SDTR je p_mesginSDTR - cmp REJBYTE_EXT,MSG_WDTR je p_mesginWDTR - jmp rej_mesgin - -p_mesginWDTR: - cmp ARG_1,2 jne rej_mesgin /* extended mesg length=2 */ - mvi ARG_1 call inb_next /* Width of bus */ - mvi INTSTAT,WDTR_MSG /* let driver know */ - test RETURN_1,0xff jz mesgin_done /* Do we need to send WDTR? */ - cmp RETURN_1,SEND_REJ je rej_mesgin /* - * Bus width was too large - * Reject it. - */ - -/* We didn't initiate the wide negotiation, so we must respond to the request */ - and RETURN_1,0x7f /* Clear the SEND_WDTR Flag */ - mvi DINDEX,MSG0 - mvi MSG0 call mk_wdtr /* build WDTR message */ - or SCSISIGO,ATNO /* turn on ATNO */ - jmp mesgin_done - -p_mesginSDTR: - cmp ARG_1,3 jne rej_mesgin /* extended mesg length=3 */ - mvi ARG_1 call inb_next /* xfer period */ - mvi A call inb_next /* REQ/ACK offset */ - mvi INTSTAT,SDTR_MSG /* call driver to convert */ - - test RETURN_1,0xff jz mesgin_done /* Do we need to mk_sdtr/rej */ - cmp RETURN_1,SEND_REJ je rej_mesgin /* - * Requested SDTR too small - * Reject it. - */ - clr ARG_1 /* Use the scratch ram rate */ - mvi DINDEX, MSG0 - mvi MSG0 call mk_sdtr - or SCSISIGO,ATNO /* turn on ATNO */ - jmp mesgin_done - -/* - * Is it a disconnect message? Set a flag in the SCB to remind us - * and await the bus going free. - */ -mesgin_disconnect: - or SCB_CONTROL,DISCONNECTED - test FLAGS, PAGESCBS jz mesgin_done -/* - * Link this SCB into the DISCONNECTED list. This list holds the - * candidates for paging out an SCB if one is needed for a new command. - * Modifying the disconnected list is a critical(pause dissabled) section. - */ - mvi SCB_PREV, SCB_LIST_NULL - mvi SEQCTL,0x50 /* PAUSEDIS|FASTMODE */ - mov SCB_NEXT, DISCONNECTED_SCBH - mov DISCONNECTED_SCBH, SCBPTR - cmp SCB_NEXT,SCB_LIST_NULL je linkdone - mov SCBPTR,SCB_NEXT - mov SCB_PREV,DISCONNECTED_SCBH - mov SCBPTR,DISCONNECTED_SCBH -linkdone: - mvi SEQCTL,0x10 /* !PAUSEDIS|FASTMODE */ - jmp mesgin_done - -/* - * Save data pointers message? Copy working values into the SCB, - * usually in preparation for a disconnect. - */ -mesgin_sdptrs: - call sg_ram2scb - jmp mesgin_done - -/* - * Restore pointers message? Data pointers are recopied from the - * SCB anytime we enter a data phase for the first time, so all - * we need to do is clear the DPHASE flag and let the data phase - * code do the rest. - */ -mesgin_rdptrs: - and FLAGS,0xef /* - * !DPHASE we'll reload them - * the next time through - */ - jmp mesgin_done - -/* - * Identify message? For a reconnecting target, this tells us the lun - * that the reconnection is for - find the correct SCB and switch to it, - * clearing the "disconnected" bit so we don't "find" it by accident later. - */ -mesgin_identify: - test A,0x78 jnz rej_mesgin /*!DiscPriv|!LUNTAR|!Reserved*/ - - and A,0x07 /* lun in lower three bits */ - or SAVED_TCL,A,SELID - and SAVED_TCL,0xf7 - and A,SELBUSB,SBLKCTL /* B Channel?? */ - or SAVED_TCL,A - call inb_last /* ACK */ - -/* - * Here we "snoop" the bus looking for a SIMPLE QUEUE TAG message. - * If we get one, we use the tag returned to switch to find the proper - * SCB. With SCB paging, this requires using findSCB for both tagged - * and non-tagged transactions since the SCB may exist in any slot. - * If we're not using SCB paging, we can use the tag as the direct - * index to the SCB. - */ - mvi ARG_1,SCB_LIST_NULL /* Default to no-tag */ -snoop_tag_loop: - test SSTAT1,BUSFREE jnz use_findSCB - test SSTAT1,REQINIT jz snoop_tag_loop - test SSTAT1,PHASEMIS jnz use_findSCB - mvi A call inb_first - cmp A,MSG_SIMPLE_TAG jne use_findSCB -get_tag: - mvi ARG_1 call inb_next /* tag value */ -/* - * See if the tag is in range. The tag is < SCBCOUNT if we add - * the complement of SCBCOUNT to the incoming tag and there is - * no carry. - */ - mov A,COMP_SCBCOUNT - add SINDEX,A,ARG_1 - jc abort_tag - -/* - * Ensure that the SCB the tag points to is for a SCB transaction - * to the reconnecting target. - */ - test FLAGS, PAGESCBS jz index_by_tag - call inb_last /* Ack Tag */ -use_findSCB: - mov ALLZEROS call findSCB /* Have to search */ -setup_SCB: - and SCB_CONTROL,0xfb /* clear disconnect bit in SCB */ - or FLAGS,IDENTIFY_SEEN /* make note of IDENTIFY */ - jmp ITloop -index_by_tag: - mov SCBPTR,ARG_1 - mov A,SAVED_TCL - cmp SCB_TCL,A jne abort_tag - test SCB_CONTROL,TAG_ENB jz abort_tag - call inb_last /* Ack Successful tag */ - jmp setup_SCB - -abort_tag: - or SCSISIGO,ATNO /* turn on ATNO */ - mvi INTSTAT,ABORT_TAG /* let driver know */ - mvi MSG_ABORT_TAG call mk_mesg /* ABORT TAG message */ - jmp mesgin_done - -/* - * Message reject? Let the kernel driver handle this. If we have an - * outstanding WDTR or SDTR negotiation, assume that it's a response from - * the target selecting 8bit or asynchronous transfer, otherwise just ignore - * it since we have no clue what it pertains to. - */ -mesgin_reject: - mvi INTSTAT, REJECT_MSG - jmp mesgin_done - -/* - * [ ADD MORE MESSAGE HANDLING HERE ] - */ - -/* - * Bus free phase. It might be useful to interrupt the device - * driver if we aren't expecting this. For now, make sure that - * ATN isn't being asserted and look for a new command. - */ -p_busfree: - mvi CLRSINT1,CLRATNO - clr LASTPHASE - -/* - * if this is an immediate command, perform a pseudo command complete to - * notify the driver. - */ - test SCB_CMDLEN,0xff jz status_ok - jmp start - -/* - * Locking the driver out, build a one-byte message passed in SINDEX - * if there is no active message already. SINDEX is returned intact. - */ -mk_mesg: - mvi SEQCTL,0x50 /* PAUSEDIS|FASTMODE */ - test MSG_LEN,0xff jz mk_mesg1 /* Should always succeed */ - - /* - * Hmmm. For some reason the mesg buffer is in use. - * Tell the driver. It should look at SINDEX to find - * out what we wanted to use the buffer for and resolve - * the conflict. - */ - mvi SEQCTL,0x10 /* !PAUSEDIS|FASTMODE */ - mvi INTSTAT,MSG_BUFFER_BUSY - -mk_mesg1: - mvi MSG_LEN,1 /* length = 1 */ - mov MSG0,SINDEX /* 1-byte message */ - mvi SEQCTL,0x10 ret /* !PAUSEDIS|FASTMODE */ - -/* - * Functions to read data in Automatic PIO mode. - * - * According to Adaptec's documentation, an ACK is not sent on input from - * the target until SCSIDATL is read from. So we wait until SCSIDATL is - * latched (the usual way), then read the data byte directly off the bus - * using SCSIBUSL. When we have pulled the ATN line, or we just want to - * acknowledge the byte, then we do a dummy read from SCISDATL. The SCSI - * spec guarantees that the target will hold the data byte on the bus until - * we send our ACK. - * - * The assumption here is that these are called in a particular sequence, - * and that REQ is already set when inb_first is called. inb_{first,next} - * use the same calling convention as inb. - */ - -inb_next: - or CLRSINT0, CLRSPIORDY - mov NONE,SCSIDATL /*dummy read from latch to ACK*/ -inb_next_wait: - test SSTAT1,PHASEMIS jnz mesgin_phasemis - test SSTAT0,SPIORDY jz inb_next_wait /* wait for next byte */ -inb_first: - mov DINDEX,SINDEX - test SSTAT1,PHASEMIS jnz mesgin_phasemis - mov DINDIR,SCSIBUSL ret /*read byte directly from bus*/ -inb_last: - mov NONE,SCSIDATL ret /*dummy read from latch to ACK*/ - -mesgin_phasemis: -/* - * We expected to receive another byte, but the target changed phase - */ - mvi INTSTAT, MSGIN_PHASEMIS - jmp ITloop - -/* - * DMA data transfer. HADDR and HCNT must be loaded first, and - * SINDEX should contain the value to load DFCNTRL with - 0x3d for - * host->scsi, or 0x39 for scsi->host. The SCSI channel is cleared - * during initialization. - */ -dma: - mov DFCNTRL,SINDEX -dma1: - test SSTAT0,DMADONE jnz dma3 - test SSTAT1,PHASEMIS jz dma1 /* ie. underrun */ - -/* - * We will be "done" DMAing when the transfer count goes to zero, or - * the target changes the phase (in light of this, it makes sense that - * the DMA circuitry doesn't ACK when PHASEMIS is active). If we are - * doing a SCSI->Host transfer, the data FIFO should be flushed auto- - * magically on STCNT=0 or a phase change, so just wait for FIFO empty - * status. - */ -dma3: - test SINDEX,DIRECTION jnz dma5 -dma4: - test DFSTATUS,FIFOEMP jz dma4 - -/* - * Now shut the DMA enables off and make sure that the DMA enables are - * actually off first lest we get an ILLSADDR. - */ -dma5: - /* disable DMA, but maintain WIDEODD */ - and DFCNTRL,WIDEODD -dma6: - test DFCNTRL,0x38 jnz dma6 /* SCSIENACK|SDMAENACK|HDMAENACK */ - - ret - -/* - * Common SCSI initialization for selection and reselection. Expects - * the target SCSI ID to be in the upper four bits of SINDEX, and A's - * contents are stomped on return. - */ -initialize_scsiid: - and SINDEX,0xf0 /* Get target ID */ - and A,0x0f,SCSIID - or SINDEX,A - mov SCSIID,SINDEX ret - -/* - * Assert that if we've been reselected, then we've seen an IDENTIFY - * message. - */ -assert: - test FLAGS,RESELECTED jz return /* reselected? */ - test FLAGS,IDENTIFY_SEEN jnz return /* seen IDENTIFY? */ - - mvi INTSTAT,NO_IDENT ret /* no - cause a kernel panic */ - -/* - * Locate the SCB matching the target ID/channel/lun in SAVED_TCL, and the tag - * value in ARG_1. If ARG_1 == SCB_LIST_NULL, we're looking for a non-tagged - * SCB. Have the kernel print a warning message if it can't be found, and - * generate an ABORT/ABORT_TAG message to the target. SINDEX should be - * cleared on call. - */ -findSCB: - mov A,SAVED_TCL - mov SCBPTR,SINDEX /* switch to next SCB */ - mvi SEQCTL,0x50 /* PAUSEDIS|FASTMODE */ - cmp SCB_TCL,A jne findSCB1 /* target ID/channel/lun match? */ - test SCB_CONTROL,DISCONNECTED jz findSCB1 /*should be disconnected*/ - test SCB_CONTROL,TAG_ENB jnz findTaggedSCB - cmp ARG_1,SCB_LIST_NULL je foundSCB - jmp findSCB1 -findTaggedSCB: - mov A, ARG_1 /* Tag passed in ARG_1 */ - cmp SCB_TAG,A jne findSCB1 /* Found it? */ -foundSCB: - test FLAGS,PAGESCBS jz foundSCB_ret -/* Remove this SCB from the disconnection list */ - cmp SCB_NEXT,SCB_LIST_NULL je unlink_prev - mov SAVED_LINKPTR, SCB_PREV - mov SCBPTR, SCB_NEXT - mov SCB_PREV, SAVED_LINKPTR - mov SCBPTR, SINDEX -unlink_prev: - cmp SCB_PREV,SCB_LIST_NULL je rHead/* At the head of the list */ - mov SAVED_LINKPTR, SCB_NEXT - mov SCBPTR, SCB_PREV - mov SCB_NEXT, SAVED_LINKPTR - mov SCBPTR, SINDEX - mvi SEQCTL,0x10 ret /* !PAUSEDIS|FASTMODE */ -rHead: - mov DISCONNECTED_SCBH,SCB_NEXT -foundSCB_ret: - mvi SEQCTL,0x10 ret /* !PAUSEDIS|FASTMODE */ - -findSCB1: - mvi SEQCTL,0x10 /* !PAUSEDIS|FASTMODE */ - inc SINDEX - mov A,SCBCOUNT - cmp SINDEX,A jne findSCB - - mvi INTSTAT,NO_MATCH /* not found - signal kernel */ - cmp RETURN_1,SCB_PAGEDIN je return - or SCSISIGO,ATNO /* assert ATNO */ - cmp ARG_1,SCB_LIST_NULL jne find_abort_tag - mvi MSG_ABORT call mk_mesg - jmp ITloop -find_abort_tag: - mvi MSG_ABORT_TAG call mk_mesg - jmp ITloop - -/* - * Make a working copy of the scatter-gather parameters from the SCB. - */ -sg_scb2ram: - mov HADDR0, SCB_DATAPTR0 - mov HADDR1, SCB_DATAPTR1 - mov HADDR2, SCB_DATAPTR2 - mov HADDR3, SCB_DATAPTR3 - mov HCNT0, SCB_DATACNT0 - mov HCNT1, SCB_DATACNT1 - mov HCNT2, SCB_DATACNT2 - - mov STCNT0, HCNT0 - mov STCNT1, HCNT1 - mov STCNT2, HCNT2 - - mov SG_COUNT,SCB_SGCOUNT - - mov SG_NEXT0, SCB_SGPTR0 - mov SG_NEXT1, SCB_SGPTR1 - mov SG_NEXT2, SCB_SGPTR2 - mov SG_NEXT3, SCB_SGPTR3 ret - -/* - * Copying RAM values back to SCB, for Save Data Pointers message, but - * only if we've actually been into a data phase to change them. This - * protects against bogus data in scratch ram and the residual counts - * since they are only initialized when we go into data_in or data_out. - */ -sg_ram2scb: - test FLAGS, DPHASE jz return - mov SCB_SGCOUNT,SG_COUNT - - mov SCB_SGPTR0,SG_NEXT0 - mov SCB_SGPTR1,SG_NEXT1 - mov SCB_SGPTR2,SG_NEXT2 - mov SCB_SGPTR3,SG_NEXT3 - - mov SCB_DATAPTR0,SHADDR0 - mov SCB_DATAPTR1,SHADDR1 - mov SCB_DATAPTR2,SHADDR2 - mov SCB_DATAPTR3,SHADDR3 - -/* - * Use the residual number since STCNT is corrupted by any message transfer - */ - mov SCB_DATACNT0,SCB_RESID_DCNT0 - mov SCB_DATACNT1,SCB_RESID_DCNT1 - mov SCB_DATACNT2,SCB_RESID_DCNT2 ret - -/* - * Add the array base TARG_SCRATCH to the target offset (the target address - * is in SCSIID), and return the result in SINDEX. The accumulator - * contains the 3->8 decoding of the target ID on return. - */ -ndx_dtr: - shr A,SCSIID,4 - test SBLKCTL,SELBUSB jz ndx_dtr_2 - or A,0x08 /* Channel B entries add 8 */ -ndx_dtr_2: - add SINDEX,TARG_SCRATCH,A ret - -/* - * If we need to negotiate transfer parameters, build the WDTR or SDTR message - * starting at the address passed in SINDEX. DINDEX is modified on return. - * The SCSI-II spec requires that Wide negotiation occur first and you can - * only negotiate one or the other at a time otherwise in the event of a message - * reject, you wouldn't be able to tell which message was the culprit. - */ -mk_dtr: - test SCB_CONTROL,NEEDWDTR jnz mk_wdtr_16bit - mvi ARG_1, MAXOFFSET /* Force an offset of 15 or 8 if WIDE */ - -mk_sdtr: - mvi DINDIR,1 /* extended message */ - mvi DINDIR,3 /* extended message length = 3 */ - mvi DINDIR,1 /* SDTR code */ - call sdtr_to_rate - mov DINDIR,RETURN_1 /* REQ/ACK transfer period */ - cmp ARG_1, MAXOFFSET je mk_sdtr_max_offset - and DINDIR,0x0f,SINDIR /* Sync Offset */ - -mk_sdtr_done: - add MSG_LEN,COMP_MSG0,DINDEX ret /* update message length */ - -mk_sdtr_max_offset: -/* - * We're initiating sync negotiation, so request the max offset we can (15 or 8) - */ - /* Talking to a WIDE device? */ - test SCSIRATE, WIDEXFER jnz wmax_offset - mvi DINDIR, MAX_OFFSET_8BIT - jmp mk_sdtr_done - -wmax_offset: - mvi DINDIR, MAX_OFFSET_16BIT - jmp mk_sdtr_done - -mk_wdtr_16bit: - mvi ARG_1,BUS_16_BIT -mk_wdtr: - mvi DINDIR,1 /* extended message */ - mvi DINDIR,2 /* extended message length = 2 */ - mvi DINDIR,3 /* WDTR code */ - mov DINDIR,ARG_1 /* bus width */ - - add MSG_LEN,COMP_MSG0,DINDEX ret /* update message length */ - -sdtr_to_rate: - call ndx_dtr /* index scratch space for target */ - shr A,SINDIR,0x4 - dec SINDEX /* Preserve SINDEX */ - and A,0x7 - clr RETURN_1 -sdtr_to_rate_loop: - test A,0x0f jz sdtr_to_rate_done - add RETURN_1,0x19 - dec A - jmp sdtr_to_rate_loop -sdtr_to_rate_done: - shr RETURN_1,0x2 - add RETURN_1,0x19 - test SXFRCTL0,ULTRAEN jz return - shr RETURN_1,0x1 -return: - ret |