/* * Adaptec 274x/284x/294x device driver firmware for Linux and FreeBSD. * * Copyright (c) 1994-1999 Justin Gibbs. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions, and the following disclaimer, * without modification, immediately at the beginning of the file. * 2. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * Where this Software is combined with software released under the terms of * the GNU Public License (GPL) and the terms of the GPL would require the * combined work to also be released under the terms of the GPL, the terms * and conditions of this License will apply in addition to those of the * GPL with the exception of any terms or conditions of this License that * conflict with, or are expressly prohibited by, the GPL. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $Id: aic7xxx.seq,v 1.84 1999/01/14 06:14:15 gibbs Exp $ */ #include #include /* * A few words on the waiting SCB list: * 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 psuedo-next pointer and to thread a list * of SCBs that are awaiting selection. Since 0-0xfe are valid SCB indexes, * SCB_LIST_NULL is 0xff which is out of range. An entry is also added to * this list everytime a request sense occurs or after completing a non-tagged * command for which a second SCB has been queued. The sequencer will * automatically consume the entries. */ reset: clr SCSISIGO; /* De-assert BSY */ and SXFRCTL1, ~BITBUCKET; /* Always allow reselection */ and SCSISEQ, ENSELI|ENRSELI|ENAUTOATNP, SCSISEQ_TEMPLATE; if ((ahc->features & AHC_CMD_CHAN) != 0) { /* Ensure that no DMA operations are in progress */ clr CCSGCTL; clr CCSCBCTL; } call clear_target_state; poll_for_work: and SXFRCTL0, ~SPIOEN; if ((ahc->features & AHC_QUEUE_REGS) == 0) { mov A, QINPOS; } poll_for_work_loop: if ((ahc->features & AHC_QUEUE_REGS) == 0) { and SEQCTL, ~PAUSEDIS; } test SSTAT0, SELDO|SELDI jnz selection; test SCSISEQ, ENSELO jnz poll_for_work; if ((ahc->features & AHC_TWIN) != 0) { /* * Twin channel devices cannot handle things like SELTO * interrupts on the "background" channel. So, if we * are selecting, keep polling the current channel util * either a selection or reselection occurs. */ xor SBLKCTL,SELBUSB; /* Toggle to the other bus */ test SSTAT0, SELDO|SELDI jnz selection; test SCSISEQ, ENSELO jnz poll_for_work; xor SBLKCTL,SELBUSB; /* Toggle back */ } cmp WAITING_SCBH,SCB_LIST_NULL jne start_waiting; test_queue: /* Has the driver posted any work for us? */ if ((ahc->features & AHC_QUEUE_REGS) != 0) { test QOFF_CTLSTA, SCB_AVAIL jz poll_for_work_loop; mov NONE, SNSCB_QOFF; inc QINPOS; } else { or SEQCTL, PAUSEDIS; cmp KERNEL_QINPOS, A je poll_for_work_loop; inc QINPOS; and SEQCTL, ~PAUSEDIS; } /* * We have at least one queued SCB now and we don't have any * SCBs in the list of SCBs awaiting selection. If we have * any SCBs available for use, pull the tag from the QINFIFO * and get to work on it. */ if ((ahc->flags & AHC_PAGESCBS) != 0) { mov ALLZEROS call get_free_or_disc_scb; } dequeue_scb: add A, -1, QINPOS; mvi QINFIFO_OFFSET call fetch_byte; if ((ahc->flags & AHC_PAGESCBS) == 0) { /* In the non-paging case, the SCBID == hardware SCB index */ mov SCBPTR, RETURN_2; } dma_queued_scb: /* * DMA the SCB from host ram into the current SCB location. */ mvi DMAPARAMS, HDMAEN|DIRECTION|FIFORESET; mov RETURN_2 call dma_scb; /* * Preset the residual fields in case we never go through a data phase. * This isn't done by the host so we can avoid a DMA to clear these * fields for the normal case of I/O that completes without underrun * or overrun conditions. */ if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov SCB_RESID_DCNT, SCB_DATACNT, 3; } else { mov SCB_RESID_DCNT[0],SCB_DATACNT[0]; mov SCB_RESID_DCNT[1],SCB_DATACNT[1]; mov SCB_RESID_DCNT[2],SCB_DATACNT[2]; } mov SCB_RESID_SGCNT, SCB_SGCOUNT; start_scb: /* * Place us on the waiting list in case our selection * doesn't win during bus arbitration. */ mov SCB_NEXT,WAITING_SCBH; mov WAITING_SCBH, SCBPTR; start_waiting: /* * Pull the first entry off of the waiting SCB list. */ mov SCBPTR, WAITING_SCBH; call start_selection; jmp poll_for_work; start_selection: if ((ahc->features & AHC_TWIN) != 0) { and SINDEX,~SELBUSB,SBLKCTL;/* Clear channel select bit */ and A,SELBUSB,SCB_TCL; /* Get new channel bit */ or SINDEX,A; mov SBLKCTL,SINDEX; /* select channel */ } initialize_scsiid: if ((ahc->features & AHC_ULTRA2) != 0) { and A, TID, SCB_TCL; /* Get target ID */ and SCSIID_ULTRA2, OID; /* Clear old target */ or SCSIID_ULTRA2, A; } else { and A, TID, SCB_TCL; /* Get target ID */ and SCSIID, OID; /* Clear old target */ or SCSIID, A; } mov SINDEX, SCSISEQ_TEMPLATE; if ((ahc->flags & AHC_TARGETMODE) != 0) { test SCB_CONTROL, TARGET_SCB jz . + 2; or SINDEX, TEMODE; } mov SCSISEQ, SINDEX ret; /* * Initialize transfer settings and clear the SCSI channel. * SINDEX should contain any additional bit's the client wants * set in SXFRCTL0. We also assume that the current SCB is * a valid SCB for the target we wish to talk to. */ initialize_channel: or SXFRCTL0, CLRSTCNT|CLRCHN, SINDEX; set_transfer_settings: if ((ahc->features & AHC_ULTRA) != 0) { test SCB_CONTROL, ULTRAENB jz . + 2; or SXFRCTL0, FAST20; } /* * Initialize SCSIRATE with the appropriate value for this target. */ if ((ahc->features & AHC_ULTRA2) != 0) { bmov SCSIRATE, SCB_SCSIRATE, 2 ret; } else { mov SCSIRATE, SCB_SCSIRATE ret; } selection: test SSTAT0,SELDO jnz select_out; mvi CLRSINT0, CLRSELDI; select_in: if ((ahc->flags & AHC_TARGETMODE) != 0) { if ((ahc->flags & AHC_INITIATORMODE) != 0) { test SSTAT0, TARGET jz initiator_reselect; } /* * We've just been selected. Assert BSY and * setup the phase for receiving messages * from the target. */ mvi SCSISIGO, P_MESGOUT|BSYO; mvi CLRSINT1, CLRBUSFREE; /* * Setup the DMA for sending the identify and * command information. */ or SEQ_FLAGS, CMDPHASE_PENDING; /* XXX If ring buffer is full, return busy or queue full */ mov A, TQINPOS; if ((ahc->features & AHC_CMD_CHAN) != 0) { mvi DINDEX, CCHADDR; mvi TMODE_CMDADDR call set_32byte_addr; mvi CCSCBCTL, CCSCBRESET; } else { mvi DINDEX, HADDR; mvi TMODE_CMDADDR call set_32byte_addr; mvi DFCNTRL, FIFORESET; } /* Initiator that selected us */ and SAVED_TCL, SELID_MASK, SELID; if ((ahc->features & AHC_CMD_CHAN) != 0) { mov CCSCBRAM, SAVED_TCL; } else { mov DFDAT, SAVED_TCL; } /* The Target ID we were selected at */ if ((ahc->features & AHC_MULTI_TID) != 0) { if ((ahc->features & AHC_CMD_CHAN) != 0) { and CCSCBRAM, 0x0f, TARGIDIN; } else { and DFDAT, 0x0f, TARGIDIN; } } else { if ((ahc->features & AHC_CMD_CHAN) != 0) { and CCSCBRAM, OID, SCSIID; } else { and DFDAT, OID, SCSIID; } } /* No tag yet */ mvi INITIATOR_TAG, SCB_LIST_NULL; /* * If ATN isn't asserted, the target isn't interested * in talking to us. Go directly to bus free. */ test SCSISIGI, ATNI jz target_busfree; /* * Watch ATN closely now as we pull in messages from the * initiator. We follow the guidlines from section 6.5 * of the SCSI-2 spec for what messages are allowed when. */ call target_inb; /* * Our first message must be one of IDENTIFY, ABORT, or * BUS_DEVICE_RESET. */ /* XXX May need to be more lax here for older initiators... */ test DINDEX, MSG_IDENTIFYFLAG jz host_target_message_loop; /* Store for host */ if ((ahc->features & AHC_CMD_CHAN) != 0) { mov CCSCBRAM, DINDEX; } else { mov DFDAT, DINDEX; } /* Remember for disconnection decision */ test DINDEX, MSG_IDENTIFY_DISCFLAG jnz . + 2; /* XXX Honor per target settings too */ or SEQ_FLAGS, NO_DISCONNECT; test SCSISIGI, ATNI jz ident_messages_done; call target_inb; /* * If this is a tagged request, the tagged message must * immediately follow the identify. We test for a valid * tag message by seeing if it is >= MSG_SIMPLE_Q_TAG and * < MSG_IGN_WIDE_RESIDUE. */ add A, -MSG_SIMPLE_Q_TAG, DINDEX; jnc ident_messages_done; add A, -MSG_IGN_WIDE_RESIDUE, DINDEX; jc ident_messages_done; /* Store for host */ if ((ahc->features & AHC_CMD_CHAN) != 0) { mov CCSCBRAM, DINDEX; } else { mov DFDAT, DINDEX; } /* * If the initiator doesn't feel like providing a tag number, * we've got a failed selection and must transition to bus * free. */ test SCSISIGI, ATNI jz target_busfree; /* * Store the tag for the host. */ call target_inb; if ((ahc->features & AHC_CMD_CHAN) != 0) { mov CCSCBRAM, DINDEX; } else { mov DFDAT, DINDEX; } mov INITIATOR_TAG, DINDEX; jmp ident_messages_done; /* * Pushed message loop to allow the kernel to * run it's own target mode message state engine. */ host_target_message_loop: mvi INTSTAT, HOST_MSG_LOOP; nop; cmp RETURN_1, EXIT_MSG_LOOP je target_ITloop; test SSTAT0, SPIORDY jz .; jmp host_target_message_loop; ident_messages_done: /* Terminate the ident list */ if ((ahc->features & AHC_CMD_CHAN) != 0) { mvi CCSCBRAM, SCB_LIST_NULL; } else { mvi DFDAT, SCB_LIST_NULL; } or SEQ_FLAGS, TARG_CMD_PENDING|IDENTIFY_SEEN; test SCSISIGI, ATNI jnz target_mesgout_pending_msg; jmp target_ITloop; /* * We carefully toggle SPIOEN to allow us to return the * message byte we receive so it can be checked prior to * driving REQ on the bus for the next byte. */ target_inb: /* * Drive REQ on the bus by enabling SCSI PIO. */ or SXFRCTL0, SPIOEN; /* Wait for the byte */ test SSTAT0, SPIORDY jz .; /* Prevent our read from triggering another REQ */ and SXFRCTL0, ~SPIOEN; /* Save latched contents */ mov DINDEX, SCSIDATL ret; } if ((ahc->flags & AHC_INITIATORMODE) != 0) { /* * 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. */ initiator_reselect: /* XXX test for and handle ONE BIT condition */ and SAVED_TCL, SELID_MASK, SELID; if ((ahc->features & AHC_TWIN) != 0) { test SBLKCTL, SELBUSB jz . + 2; or SAVED_TCL, SELBUSB; } or SXFRCTL0, SPIOEN|CLRSTCNT|CLRCHN; mvi CLRSINT1,CLRBUSFREE; or SIMODE1, ENBUSFREE; /* * We aren't expecting a * bus free, so interrupt * the kernel driver if it * happens. */ mvi MSG_OUT, MSG_NOOP; /* No message to send */ jmp ITloop; } /* * After the selection, remove this SCB from the "waiting SCB" * 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_out: /* Turn off the selection hardware */ and SCSISEQ, ENSELI|ENRSELI|ENAUTOATNP, SCSISEQ_TEMPLATE; mvi CLRSINT0, CLRSELDO; mov SCBPTR, WAITING_SCBH; mov WAITING_SCBH,SCB_NEXT; mov SAVED_TCL, SCB_TCL; if ((ahc->flags & AHC_TARGETMODE) != 0) { test SSTAT0, TARGET jz initiator_select; /* * We've just re-selected an initiator. * Assert BSY and setup the phase for * sending our identify messages. */ mvi P_MESGIN|BSYO call change_phase; mvi CLRSINT1,CLRBUSFREE; /* * Start out with a simple identify message. */ and A, LID, SCB_TCL; or A, MSG_IDENTIFYFLAG call target_outb; /* * If we are the result of a tagged command, send * a simple Q tag and the tag id. */ test SCB_CONTROL, TAG_ENB jz . + 3; mvi MSG_SIMPLE_Q_TAG call target_outb; mov SCB_INITIATOR_TAG call target_outb; mov INITIATOR_TAG, SCB_INITIATOR_TAG; target_synccmd: /* * Now determine what phases the host wants us * to go through. */ mov SEQ_FLAGS, SCB_TARGET_PHASES; target_ITloop: /* * Start honoring ATN signals now that * we properly identified ourself. */ test SCSISIGI, ATNI jnz target_mesgout; test SEQ_FLAGS, CMDPHASE_PENDING jnz target_cmdphase; test SEQ_FLAGS, DPHASE_PENDING jnz target_dphase; test SEQ_FLAGS, SPHASE_PENDING jnz target_sphase; /* * No more work to do. Either disconnect or not depending * on the state of NO_DISCONNECT. */ test SEQ_FLAGS, NO_DISCONNECT jz target_disconnect; if ((ahc->flags & AHC_PAGESCBS) != 0) { mov ALLZEROS call get_free_or_disc_scb; } mov RETURN_1, ALLZEROS; call complete_target_cmd; cmp RETURN_1, CONT_MSG_LOOP jne .; mvi DMAPARAMS, HDMAEN|DIRECTION|FIFORESET; mov SCB_TAG call dma_scb; jmp target_synccmd; target_mesgout: mvi SCSISIGO, P_MESGOUT|BSYO; call target_inb; /* Local Processing goes here... */ target_mesgout_pending_msg: jmp host_target_message_loop; target_disconnect: mvi P_MESGIN|BSYO call change_phase; test SEQ_FLAGS, DPHASE jz . + 2; mvi MSG_SAVEDATAPOINTER call target_outb; mvi MSG_DISCONNECT call target_outb; target_busfree_wait: /* Wait for preceeding I/O session to complete. */ test SCSISIGI, ACKI jnz .; target_busfree: clr SCSISIGO; call complete_target_cmd; call clear_target_state; jmp poll_for_work; target_cmdphase: mvi P_COMMAND|BSYO call change_phase; call target_inb; mov A, DINDEX; /* Store for host */ if ((ahc->features & AHC_CMD_CHAN) != 0) { mov CCSCBRAM, A; } else { mov DFDAT, A; } /* * Determine the number of bytes to read * based on the command group code via table lookup. * We reuse the first 8 bytes of the TARG_SCSIRATE * BIOS array for this table. Count is one less than * the total for the command since we've already fetched * the first byte. */ shr A, CMD_GROUP_CODE_SHIFT; add SINDEX, TARG_SCSIRATE, A; mov A, SINDIR; test A, 0xFF jz command_phase_done; command_loop: or SXFRCTL0, SPIOEN; test SSTAT0, SPIORDY jz .; cmp A, 1 jne . + 2; and SXFRCTL0, ~SPIOEN; /* Last Byte */ if ((ahc->features & AHC_CMD_CHAN) != 0) { mov CCSCBRAM, SCSIDATL; } else { mov DFDAT, SCSIDATL; } dec A; test A, 0xFF jnz command_loop; command_phase_done: and SEQ_FLAGS, ~CMDPHASE_PENDING; jmp target_ITloop; target_dphase: /* * Data direction flags are from the * perspective of the initiator. */ test SCB_TARGET_PHASES[1], TARGET_DATA_IN jz . + 4; mvi LASTPHASE, P_DATAOUT; mvi P_DATAIN|BSYO call change_phase; jmp . + 3; mvi LASTPHASE, P_DATAIN; mvi P_DATAOUT|BSYO call change_phase; mov ALLZEROS call initialize_channel; jmp p_data; target_sphase: mvi P_STATUS|BSYO call change_phase; mvi LASTPHASE, P_STATUS; mov SCB_TARGET_STATUS call target_outb; /* XXX Watch for ATN or parity errors??? */ mvi SCSISIGO, P_MESGIN|BSYO; /* MSG_CMDCMPLT is 0, but we can't do an immediate of 0 */ mov ALLZEROS call target_outb; jmp target_busfree_wait; complete_target_cmd: test SEQ_FLAGS, TARG_CMD_PENDING jnz . + 2; mov SCB_TAG jmp complete_post; if ((ahc->features & AHC_CMD_CHAN) != 0) { /* Set the valid byte */ mvi CCSCBADDR, 24; mov CCSCBRAM, ALLONES; mvi CCHCNT, 28; or CCSCBCTL, CCSCBEN|CCSCBRESET; test CCSCBCTL, CCSCBDONE jz .; clr CCSCBCTL; } else { /* Set the valid byte */ or DFCNTRL, FIFORESET; mvi DFWADDR, 3; /* Third 64bit word or byte 24 */ mov DFDAT, ALLONES; mvi HCNT[0], 28; clr HCNT[1]; clr HCNT[2]; or DFCNTRL, HDMAEN|FIFOFLUSH; call dma_finish; } inc TQINPOS; mvi INTSTAT,CMDCMPLT ret; } if ((ahc->flags & AHC_INITIATORMODE) != 0) { initiator_select: mvi SPIOEN call initialize_channel; /* * We aren't expecting a bus free, so interrupt * the kernel driver if it happens. */ mvi CLRSINT1,CLRBUSFREE; or SIMODE1, ENBUSFREE; /* * As soon as we get a successful selection, the target * should go into the message out phase since we have ATN * asserted. */ mvi MSG_OUT, MSG_IDENTIFYFLAG; or SEQ_FLAGS, IDENTIFY_SEEN; /* * Main loop for information transfer phases. Wait for the * target to assert REQ before checking MSG, C/D and I/O for * the bus phase. */ ITloop: call phase_lock; mov A, LASTPHASE; test A, ~P_DATAIN jz p_data; 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; jmp ITloop; /* Try reading the bus again. */ await_busfree: and SIMODE1, ~ENBUSFREE; call clear_target_state; mov NONE, SCSIDATL; /* Ack the last byte */ and SXFRCTL0, ~SPIOEN; test SSTAT1,REQINIT|BUSFREE jz .; test SSTAT1, BUSFREE jnz poll_for_work; mvi INTSTAT, BAD_PHASE; } clear_target_state: /* * We assume that the kernel driver may reset us * at any time, even in the middle of a DMA, so * clear DFCNTRL too. */ clr DFCNTRL; /* * We don't know the target we will connect to, * so default to narrow transfers to avoid * parity problems. */ if ((ahc->features & AHC_ULTRA2) != 0) { bmov SCSIRATE, ALLZEROS, 2; } else { clr SCSIRATE; and SXFRCTL0, ~(FAST20); } mvi LASTPHASE, P_BUSFREE; /* clear target specific flags */ clr SEQ_FLAGS ret; /* * 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: if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov STCNT, SCB_RESID_DCNT, 3; } else { mvi DINDEX, STCNT; mvi SCB_RESID_DCNT call bcopy_3; } and DATA_COUNT_ODD, 0x1, SCB_RESID_DCNT[0]; jmp data_phase_loop; p_data: if ((ahc->features & AHC_ULTRA2) != 0) { mvi DMAPARAMS, PRELOADEN|SCSIEN|HDMAEN; } else { mvi DMAPARAMS, WIDEODD|SCSIEN|SDMAEN|HDMAEN|FIFORESET; } test LASTPHASE, IOI jnz . + 2; or DMAPARAMS, DIRECTION; call assert; /* * Ensure entering a data * phase is okay - seen identify, etc. */ if ((ahc->features & AHC_CMD_CHAN) != 0) { mvi CCSGADDR, CCSGADDR_MAX; } test SEQ_FLAGS, DPHASE jnz data_phase_reinit; /* We have seen a data phase */ or SEQ_FLAGS, DPHASE; /* * Initialize the DMA address and counter from the SCB. * Also set SG_COUNT and SG_NEXT in memory since we cannot * modify the values in the SCB itself until we see a * save data pointers message. */ if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov HADDR, SCB_DATAPTR, 7; } else { mvi DINDEX, HADDR; mvi SCB_DATAPTR call bcopy_7; } and DATA_COUNT_ODD, 0x1, SCB_DATACNT[0]; if ((ahc->features & AHC_ULTRA2) == 0) { if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov STCNT, HCNT, 3; } else { call set_stcnt_from_hcnt; } } if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov SG_COUNT, SCB_SGCOUNT, 5; } else { mvi DINDEX, SG_COUNT; mvi SCB_SGCOUNT call bcopy_5; } 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; and DMAPARAMS, ~(HDMAEN|SDMAEN); if ((ahc->features & AHC_ULTRA2) != 0) { bmov HCNT, ALLONES, 3; } else if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov STCNT, ALLONES, 3; } else { mvi STCNT[0], 0xFF; mvi STCNT[1], 0xFF; mvi STCNT[2], 0xFF; } data_phase_inbounds: /* If we are the last SG block, tell the hardware. */ cmp SG_COUNT,0x01 jne data_phase_wideodd; if ((ahc->features & AHC_ULTRA2) != 0) { or SG_CACHEPTR, LAST_SEG; } else { and DMAPARAMS, ~WIDEODD; } data_phase_wideodd: if ((ahc->features & AHC_ULTRA2) != 0) { mov SINDEX, ALLONES; mov DFCNTRL, DMAPARAMS; test SSTAT0, SDONE jnz .;/* Wait for preload to complete */ data_phase_dma_loop: test SSTAT0, SDONE jnz data_phase_dma_done; test SSTAT1,PHASEMIS jz data_phase_dma_loop; /* ie. underrun */ data_phase_dma_phasemis: test SSTAT0,SDONE jnz . + 2; mov SINDEX,ALLZEROS; /* Remeber the phasemiss */ } else { mov DMAPARAMS call dma; } data_phase_dma_done: /* Go tell the host about any overruns */ test SXFRCTL1,BITBUCKET jnz data_phase_overrun; /* Exit if we had an underrun. dma clears SINDEX in this case. */ test SINDEX,0xff jz data_phase_finish; /* * 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? */ /* * 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 little-endian host data storage. */ sg_load: if ((ahc->features & AHC_CMD_CHAN) != 0) { /* * Do we have any prefetch left??? */ cmp CCSGADDR, CCSGADDR_MAX jne prefetched_segs_avail; /* * Fetch MIN(CCSGADDR_MAX, (SG_COUNT * 8)) bytes. */ add A, -(CCSGRAM_MAXSEGS + 1), SG_COUNT; mvi A, CCSGADDR_MAX; jc . + 2; shl A, 3, SG_COUNT; mov CCHCNT, A; bmov CCHADDR, SG_NEXT, 4; mvi CCSGCTL, CCSGEN|CCSGRESET; test CCSGCTL, CCSGDONE jz .; and CCSGCTL, ~CCSGEN; test CCSGCTL, CCSGEN jnz .; mvi CCSGCTL, CCSGRESET; prefetched_segs_avail: bmov HADDR, CCSGRAM, 8; } else { mvi DINDEX, HADDR; mvi SG_NEXT call bcopy_4; mvi HCNT[0],SG_SIZEOF; clr HCNT[1]; clr HCNT[2]; or DFCNTRL, HDMAEN|DIRECTION|FIFORESET; call dma_finish; /* * Copy data from FIFO into SCB data pointer and data count. * This assumes that the SG segments are of the form: * struct ahc_dma_seg { * u_int32_t addr; four bytes, little-endian order * u_int32_t len; four bytes, little endian order * }; */ mvi HADDR call dfdat_in_7; } /* Track odd'ness */ test HCNT[0], 0x1 jz . + 2; xor DATA_COUNT_ODD, 0x1; if ((ahc->features & AHC_ULTRA2) == 0) { /* Load STCNT as well. It is a mirror of HCNT */ if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov STCNT, HCNT, 3; } else { call set_stcnt_from_hcnt; } } /* Advance the SG pointer */ clr A; /* add sizeof(struct scatter) */ add SG_NEXT[0],SG_SIZEOF; adc SG_NEXT[1],A; if ((ahc->flags & AHC_TARGETMODE) != 0) { test SSTAT0, TARGET jnz data_phase_loop; } test SSTAT1, REQINIT jz .; test SSTAT1,PHASEMIS jz data_phase_loop; /* Ensure the last seg is visable at the shaddow layer */ if ((ahc->features & AHC_ULTRA2) != 0) { or DFCNTRL, PRELOADEN; } data_phase_finish: if ((ahc->features & AHC_ULTRA2) != 0) { call ultra2_dmafinish; } /* * 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. */ if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov SCB_RESID_DCNT, STCNT, 3; } else { mov SCB_RESID_DCNT[0],STCNT[0]; mov SCB_RESID_DCNT[1],STCNT[1]; mov SCB_RESID_DCNT[2],STCNT[2]; } mov SCB_RESID_SGCNT, SG_COUNT; if ((ahc->features & AHC_ULTRA2) != 0) { or SXFRCTL0, CLRSTCNT|CLRCHN; } if ((ahc->flags & AHC_TARGETMODE) != 0) { test SEQ_FLAGS, DPHASE_PENDING jz ITloop; and SEQ_FLAGS, ~DPHASE_PENDING; /* * For data-in phases, wait for any pending acks from the * initiator before changing phase. */ test DFCNTRL, DIRECTION jz target_ITloop; test SSTAT1, REQINIT jnz .; jmp target_ITloop; } jmp ITloop; data_phase_overrun: if ((ahc->features & AHC_ULTRA2) != 0) { call ultra2_dmafinish; or SXFRCTL0, CLRSTCNT|CLRCHN; } /* * Turn off BITBUCKET mode and notify the host */ and SXFRCTL1, ~BITBUCKET; mvi INTSTAT,DATA_OVERRUN; jmp ITloop; ultra2_dmafinish: if ((ahc->features & AHC_ULTRA2) != 0) { test DFCNTRL, DIRECTION jnz ultra2_dmahalt; and DFCNTRL, ~SCSIEN; test DFCNTRL, SCSIEN jnz .; or DFCNTRL, FIFOFLUSH; test DFSTATUS, FIFOEMP jz . - 1; ultra2_dmahalt: and DFCNTRL, ~(SCSIEN|HDMAEN); test DFCNTRL, HDMAEN jnz .; ret; } if ((ahc->flags & AHC_INITIATORMODE) != 0) { /* * Command phase. Set up the DMA registers and let 'er rip. */ p_command: call assert; if ((ahc->features & AHC_CMD_CHAN) != 0) { mov HCNT[0], SCB_CMDLEN; bmov HCNT[1], ALLZEROS, 2; if ((ahc->features & AHC_ULTRA2) == 0) { bmov STCNT, HCNT, 3; } add NONE, -17, SCB_CMDLEN; jc dma_cmd_data; if ((ahc->features & AHC_ULTRA2) != 0) { mvi DFCNTRL, (PRELOADEN|SCSIEN|DIRECTION); } else { mvi DFCNTRL, (SCSIEN|SDMAEN|DIRECTION|FIFORESET); } bmov DFDAT, SCB_CMDSTORE, 16; jmp cmd_loop; dma_cmd_data: bmov HADDR, SCB_CMDPTR, 4; } else { mvi DINDEX, HADDR; mvi SCB_CMDPTR call bcopy_5; clr HCNT[1]; clr HCNT[2]; } if ((ahc->features & AHC_ULTRA2) == 0) { if ((ahc->features & AHC_CMD_CHAN) == 0) { call set_stcnt_from_hcnt; } mvi DFCNTRL, (SCSIEN|SDMAEN|HDMAEN|DIRECTION|FIFORESET); } else { mvi DFCNTRL, (PRELOADEN|SCSIEN|HDMAEN|DIRECTION); } cmd_loop: test SSTAT0, SDONE jnz . + 2; test SSTAT1, PHASEMIS jz cmd_loop; and DFCNTRL, ~(SCSIEN|HDMAEN|SDMAEN); test DFCNTRL, (SCSIEN|SDMAEN|HDMAEN) jnz .; jmp ITloop; /* * Status phase. Wait for the data byte to appear, then read it * and store it into the SCB. */ p_status: call assert; mov SCB_TARGET_STATUS, SCSIDATL; jmp ITloop; /* * Message out phase. If MSG_OUT is MSG_IDENTIFYFLAG, build a full * indentify message sequence and send it to the target. The host may * override this behavior by setting the MK_MESSAGE bit in the SCB * control byte. This will cause us to interrupt the host and allow * it to handle the message phase completely on its own. If the bit * associated with this target is set, we will also interrupt the host, * thereby allowing it to send a message on the next selection regardless * of the transaction being sent. * * If MSG_OUT is == HOST_MSG, also interrupt the host and take a message. * This is done to allow the host to send messages outside of an identify * sequence while protecting the seqencer from testing the MK_MESSAGE bit * on an SCB that might not be for the current nexus. (For example, a * BDR message in responce to a bad reselection would leave us pointed to * an SCB that doesn't have anything to do with the current target). * * Otherwise, treat MSG_OUT as a 1 byte message to send (abort, abort tag, * bus device reset). * * When there are no messages to send, MSG_OUT should be set to MSG_NOOP, * in case the target decides to put us in this phase for some strange * reason. */ p_mesgout_retry: or SCSISIGO,ATNO,LASTPHASE;/* turn on ATN for the retry */ p_mesgout: mov SINDEX, MSG_OUT; cmp SINDEX, MSG_IDENTIFYFLAG jne p_mesgout_from_host; test SCB_CONTROL,MK_MESSAGE jnz host_message_loop; mov FUNCTION1, SCB_TCL; mov A, FUNCTION1; mov SINDEX, TARGET_MSG_REQUEST[0]; if ((ahc->features & AHC_TWIN) != 0) { /* Second Channel uses high byte bits */ test SCB_TCL, SELBUSB jz . + 2; mov SINDEX, TARGET_MSG_REQUEST[1]; } else if ((ahc->features & AHC_WIDE) != 0) { test SCB_TCL, 0x80 jz . + 2; /* target > 7 */ mov SINDEX, TARGET_MSG_REQUEST[1]; } test SINDEX, A jnz host_message_loop; p_mesgout_identify: and SINDEX,LID,SCB_TCL; /* lun */ and A,DISCENB,SCB_CONTROL; /* mask off disconnect privledge */ or SINDEX,A; /* or in disconnect privledge */ or SINDEX,MSG_IDENTIFYFLAG; /* * 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. */ p_mesgout_tag: test SCB_CONTROL,TAG_ENB jz p_mesgout_onebyte; mov SCSIDATL, SINDEX; /* Send the identify message */ call phase_lock; cmp LASTPHASE, P_MESGOUT jne p_mesgout_done; and SCSIDATL,TAG_ENB|SCB_TAG_TYPE,SCB_CONTROL; call phase_lock; cmp LASTPHASE, P_MESGOUT jne p_mesgout_done; mov SCB_TAG jmp p_mesgout_onebyte; /* * Interrupt the driver, and allow it to handle this message * phase and any required retries. */ p_mesgout_from_host: cmp SINDEX, HOST_MSG jne p_mesgout_onebyte; jmp host_message_loop; p_mesgout_onebyte: mvi CLRSINT1, CLRATNO; mov SCSIDATL, SINDEX; /* * If the next bus phase after ATN drops is message out, it means * that the target is requesting that the last message(s) be resent. */ call phase_lock; cmp LASTPHASE, P_MESGOUT je p_mesgout_retry; p_mesgout_done: mvi CLRSINT1,CLRATNO; /* Be sure to turn ATNO off */ mov LAST_MSG, MSG_OUT; mvi MSG_OUT, MSG_NOOP; /* No message left */ jmp ITloop; /* * Message in phase. Bytes are read using Automatic PIO mode. */ p_mesgin: mvi ACCUM call inb_first; /* read the 1st message byte */ test A,MSG_IDENTIFYFLAG jnz mesgin_identify; cmp A,MSG_DISCONNECT je mesgin_disconnect; cmp A,MSG_SAVEDATAPOINTER je mesgin_sdptrs; cmp ALLZEROS,A je mesgin_complete; cmp A,MSG_RESTOREPOINTERS je mesgin_rdptrs; cmp A,MSG_NOOP je mesgin_done; /* * Pushed message loop to allow the kernel to * RUN IT's own message state engine. To avoid an * extra nop instruction after signaling the kernel, * we perform the phase_lock before checking to see * if we should exit the loop and skip the phase_lock * in the ITloop. Performing back to back phase_locks * shouldn't hurt, but why do it twice... */ host_message_loop: mvi INTSTAT, HOST_MSG_LOOP; call phase_lock; cmp RETURN_1, EXIT_MSG_LOOP je ITloop + 1; jmp host_message_loop; mesgin_done: mov NONE,SCSIDATL; /*dummy read from latch to ACK*/ jmp ITloop; mesgin_complete: /* * We got a "command complete" message, so put the SCB_TAG into the QOUTFIFO, * and trigger a completion interrupt. Before doing so, check to see if there * is a residual or the status byte is something other than STATUS_GOOD (0). * In either of these conditions, we upload the SCB back to the host so it can * process this information. In the case of a non zero status byte, we * additionally interrupt the kernel driver synchronously, allowing it to * decide if sense should be retrieved. If the kernel driver wishes to request * sense, it will fill the kernel SCB with a request sense command and set * RETURN_1 to SEND_SENSE. If RETURN_1 is set to SEND_SENSE we redownload * the SCB, and process it as the next command by adding it to the waiting list. * If the kernel driver does not wish to request sense, it need only clear * RETURN_1, and the command is allowed to complete normally. We don't bother * to post to the QOUTFIFO in the error cases 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 jnz upload_scb; test SCB_TARGET_STATUS,0xff jz complete; /* Good Status? */ upload_scb: mvi DMAPARAMS, FIFORESET; mov SCB_TAG call dma_scb; check_status: test SCB_TARGET_STATUS,0xff jz complete; /* Just a residual? */ mvi INTSTAT,BAD_STATUS; /* let driver know */ nop; cmp RETURN_1, SEND_SENSE jne complete; /* This SCB becomes the next to execute as it will retrieve sense */ mvi DMAPARAMS, HDMAEN|DIRECTION|FIFORESET; mov SCB_TAG call dma_scb; add_to_waiting_list: mov SCB_NEXT,WAITING_SCBH; mov WAITING_SCBH, SCBPTR; /* * Prepare our selection hardware before the busfree so we have a * high probability of winning arbitration. */ call start_selection; jmp await_busfree; complete: /* If we are untagged, clear our address up in host ram */ test SCB_CONTROL, TAG_ENB jnz complete_queue; mov A, SAVED_TCL; mvi UNTAGGEDSCB_OFFSET call post_byte_setup; mvi SCB_LIST_NULL call post_byte; complete_queue: mov SCB_TAG call complete_post; add_to_free_list: call add_scb_to_free_list; jmp await_busfree; } complete_post: /* Post the SCBID in SINDEX and issue an interrupt */ mov ARG_1, SINDEX; if ((ahc->features & AHC_QUEUE_REGS) != 0) { mov A, SDSCB_QOFF; } else { mov A, QOUTPOS; } mvi QOUTFIFO_OFFSET call post_byte_setup; mov ARG_1 call post_byte; if ((ahc->features & AHC_QUEUE_REGS) == 0) { inc QOUTPOS; } mvi INTSTAT,CMDCMPLT ret; if ((ahc->flags & AHC_INITIATORMODE) != 0) { /* * 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; call add_scb_to_disc_list; jmp await_busfree; /* * Save data pointers message: * 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. */ mesgin_sdptrs: test SEQ_FLAGS, DPHASE jz mesgin_done; /* * The SCB SGPTR becomes the next one we'll download, * and the SCB DATAPTR becomes the current SHADDR. * Use the residual number since STCNT is corrupted by * any message transfer. */ if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov SCB_SGCOUNT, SG_COUNT, 5; bmov SCB_DATAPTR, SHADDR, 4; bmov SCB_DATACNT, SCB_RESID_DCNT, 3; } else { mvi DINDEX, SCB_SGCOUNT; mvi SG_COUNT call bcopy_5; mvi DINDEX, SCB_DATAPTR; mvi SHADDR call bcopy_4; mvi SCB_RESID_DCNT call bcopy_3; } 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 SEQ_FLAGS, ~DPHASE; /* * We'll reload them * the next time through * the dataphase. */ 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: if ((ahc->features & AHC_WIDE) != 0) { and A,0x0f; /* lun in lower four bits */ } else { and A,0x07; /* lun in lower three bits */ } or SAVED_TCL,A; /* SAVED_TCL should be complete now */ mvi ARG_2, SCB_LIST_NULL; /* SCBID of prev SCB in disc List */ call get_untagged_SCBID; cmp ARG_1, SCB_LIST_NULL je snoop_tag; if ((ahc->flags & AHC_PAGESCBS) != 0) { test SEQ_FLAGS, SCBPTR_VALID jz use_retrieveSCB; } /* * If the SCB was found in the disconnected list (as is * always the case in non-paging scenarios), SCBPTR is already * set to the correct SCB. So, simply setup the SCB and get * on with things. */ call rem_scb_from_disc_list; jmp setup_SCB; /* * Here we "snoop" the bus looking for a SIMPLE QUEUE TAG message. * If we get one, we use the tag returned to find the proper * SCB. With SCB paging, this requires using search 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. */ snoop_tag: mov NONE,SCSIDATL; /* ACK Identify MSG */ snoop_tag_loop: call phase_lock; cmp LASTPHASE, P_MESGIN jne not_found; cmp SCSIBUSL,MSG_SIMPLE_Q_TAG jne not_found; get_tag: mvi ARG_1 call inb_next; /* tag value */ /* * Ensure that the SCB the tag points to is for * an SCB transaction to the reconnecting target. */ use_retrieveSCB: call retrieveSCB; setup_SCB: mov A, SAVED_TCL; cmp SCB_TCL, A jne not_found_cleanup_scb; test SCB_CONTROL,DISCONNECTED jz not_found_cleanup_scb; and SCB_CONTROL,~DISCONNECTED; or SEQ_FLAGS,IDENTIFY_SEEN; /* make note of IDENTIFY */ call set_transfer_settings; /* See if the host wants to send a message upon reconnection */ test SCB_CONTROL, MK_MESSAGE jz mesgin_done; and SCB_CONTROL, ~MK_MESSAGE; mvi HOST_MSG call mk_mesg; jmp mesgin_done; not_found_cleanup_scb: test SCB_CONTROL, DISCONNECTED jz . + 3; call add_scb_to_disc_list; jmp not_found; call add_scb_to_free_list; not_found: mvi INTSTAT, NO_MATCH; mvi MSG_BUS_DEV_RESET call mk_mesg; jmp mesgin_done; /* * [ ADD MORE MESSAGE HANDLING HERE ] */ /* * 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: or SCSISIGO,ATNO,LASTPHASE;/* turn on ATNO */ mov MSG_OUT,SINDEX ret; /* * 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: mov NONE,SCSIDATL; /*dummy read from latch to ACK*/ inb_next_wait: /* * If there is a parity error, wait for the kernel to * see the interrupt and prepare our message response * before continuing. */ test SSTAT1, REQINIT jz inb_next_wait; test SSTAT1, SCSIPERR jnz inb_next_wait; and LASTPHASE, PHASE_MASK, SCSISIGI; cmp LASTPHASE, P_MESGIN jne mesgin_phasemis; inb_first: mov DINDEX,SINDEX; mov DINDIR,SCSIBUSL ret; /*read byte directly from bus*/ inb_last: mov NONE,SCSIDATL ret; /*dummy read from latch to ACK*/ } if ((ahc->flags & AHC_TARGETMODE) != 0) { /* * Change to a new phase. If we are changing the state of the I/O signal, * from out to in, wait an additional data release delay before continuing. */ change_phase: /* Wait for preceeding I/O session to complete. */ test SCSISIGI, ACKI jnz .; /* Change the phase */ and DINDEX, IOI, SCSISIGI; mov SCSISIGO, SINDEX; and A, IOI, SINDEX; /* * If the data direction has changed, from * out (initiator driving) to in (target driving), * we must waitat least a data release delay plus * the normal bus settle delay. [SCSI III SPI 10.11.0] */ cmp DINDEX, A je change_phase_wait; test SINDEX, IOI jz change_phase_wait; call change_phase_wait; change_phase_wait: nop; nop; nop; nop ret; /* * Send a byte to an initiator in Automatic PIO mode. */ target_outb: or SXFRCTL0, SPIOEN; test SSTAT0, SPIORDY jz .; mov SCSIDATL, SINDEX; test SSTAT0, SPIORDY jz .; and SXFRCTL0, ~SPIOEN ret; } 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; dma_loop: test SSTAT0,DMADONE jnz dma_dmadone; test SSTAT1,PHASEMIS jz dma_loop; /* ie. underrun */ dma_phasemis: test SSTAT0,SDONE jnz dma_checkfifo; mov SINDEX,ALLZEROS; /* Notify caller of phasemiss */ /* * 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. */ dma_checkfifo: test DFCNTRL,DIRECTION jnz dma_fifoempty; dma_fifoflush: test DFSTATUS,FIFOEMP jz dma_fifoflush; dma_fifoempty: /* Don't clobber an inprogress host data transfer */ test DFSTATUS, MREQPEND jnz dma_fifoempty; /* * Now shut the DMA enables off and make sure that the DMA enables are * actually off first lest we get an ILLSADDR. */ dma_dmadone: and DFCNTRL, ~(SCSIEN|SDMAEN|HDMAEN); dma_halt: /* * Some revisions of the aic7880 have a problem where, if the * data fifo is full, but the PCI input latch is not empty, * HDMAEN cannot be cleared. The fix used here is to attempt * to drain the data fifo until there is space for the input * latch to drain and HDMAEN de-asserts. */ if ((ahc->features & AHC_ULTRA2) == 0) { mov NONE, DFDAT; } test DFCNTRL, (SCSIEN|SDMAEN|HDMAEN) jnz dma_halt; return: ret; /* * Assert that if we've been reselected, then we've seen an IDENTIFY * message. */ assert: test SEQ_FLAGS,IDENTIFY_SEEN jnz return; /* seen IDENTIFY? */ mvi INTSTAT,NO_IDENT ret; /* no - tell the kernel */ /* * Locate a disconnected SCB either by SAVED_TCL (ARG_1 is SCB_LIST_NULL) * or by the SCBID ARG_1. The search begins at the SCB index passed in * via SINDEX which is an SCB that must be on the disconnected list. If * the SCB cannot be found, SINDEX will be SCB_LIST_NULL, otherwise, SCBPTR * is set to the proper SCB. */ findSCB: mov SCBPTR,SINDEX; /* Initialize SCBPTR */ cmp ARG_1, SCB_LIST_NULL jne findSCB_by_SCBID; mov A, SAVED_TCL; mvi SCB_TCL jmp findSCB_loop; /* &SCB_TCL -> SINDEX */ findSCB_by_SCBID: mov A, ARG_1; /* Tag passed in ARG_1 */ mvi SCB_TAG jmp findSCB_loop; /* &SCB_TAG -> SINDEX */ findSCB_next: mov ARG_2, SCBPTR; cmp SCB_NEXT, SCB_LIST_NULL je notFound; mov SCBPTR,SCB_NEXT; dec SINDEX; /* Last comparison moved us too far */ findSCB_loop: cmp SINDIR, A jne findSCB_next; mov SINDEX, SCBPTR ret; notFound: mvi SINDEX, SCB_LIST_NULL ret; /* * Retrieve an SCB by SCBID first searching the disconnected list falling * back to DMA'ing the SCB down from the host. This routine assumes that * ARG_1 is the SCBID of interrest and that SINDEX is the position in the * disconnected list to start the search from. If SINDEX is SCB_LIST_NULL, * we go directly to the host for the SCB. */ retrieveSCB: test SEQ_FLAGS, SCBPTR_VALID jz retrieve_from_host; mov SCBPTR call findSCB; /* Continue the search */ cmp SINDEX, SCB_LIST_NULL je retrieve_from_host; /* * This routine expects SINDEX to contain the index of the SCB to be * removed, SCBPTR to be pointing to that SCB, and ARG_2 to be the * SCBID of the SCB just previous to this one in the list or SCB_LIST_NULL * if it is at the head. */ rem_scb_from_disc_list: /* Remove this SCB from the disconnection list */ cmp ARG_2, SCB_LIST_NULL je rHead; mov DINDEX, SCB_NEXT; mov SCBPTR, ARG_2; mov SCB_NEXT, DINDEX; mov SCBPTR, SINDEX ret; rHead: mov DISCONNECTED_SCBH,SCB_NEXT ret; retrieve_from_host: /* * We didn't find it. Pull an SCB and DMA down the one we want. * We should never get here in the non-paging case. */ mov ALLZEROS call get_free_or_disc_scb; mvi DMAPARAMS, HDMAEN|DIRECTION|FIFORESET; /* Jump instead of call as we want to return anyway */ mov ARG_1 jmp dma_scb; /* * Determine whether a target is using tagged or non-tagged transactions * by first looking for a matching transaction based on the TCL and if * that fails, looking up this device in the host's untagged SCB array. * The TCL to search for is assumed to be in SAVED_TCL. The value is * returned in ARG_1 (SCB_LIST_NULL for tagged, SCBID for non-tagged). * The SCBPTR_VALID bit is set in SEQ_FLAGS if we found the information * in an SCB instead of having to go to the host. */ get_untagged_SCBID: cmp DISCONNECTED_SCBH, SCB_LIST_NULL je get_SCBID_from_host; mvi ARG_1, SCB_LIST_NULL; mov DISCONNECTED_SCBH call findSCB; cmp SINDEX, SCB_LIST_NULL je get_SCBID_from_host; or SEQ_FLAGS, SCBPTR_VALID;/* Was in disconnected list */ test SCB_CONTROL, TAG_ENB jnz . + 2; mov ARG_1, SCB_TAG ret; mvi ARG_1, SCB_LIST_NULL ret; /* * Fetch a byte from host memory given an index of (A + (256 * SINDEX)) * and a base address of SCBID_ADDR. The byte is returned in RETURN_2. */ fetch_byte: mov ARG_2, SINDEX; if ((ahc->features & AHC_CMD_CHAN) != 0) { mvi DINDEX, CCHADDR; mvi SCBID_ADDR call set_1byte_addr; mvi CCHCNT, 1; mvi CCSGCTL, CCSGEN|CCSGRESET; test CCSGCTL, CCSGDONE jz .; mvi CCSGCTL, CCSGRESET; bmov RETURN_2, CCSGRAM, 1 ret; } else { mvi DINDEX, HADDR; mvi SCBID_ADDR call set_1byte_addr; mvi HCNT[0], 1; clr HCNT[1]; clr HCNT[2]; mvi DFCNTRL, HDMAEN|DIRECTION|FIFORESET; call dma_finish; mov RETURN_2, DFDAT ret; } /* * Prepare the hardware to post a byte to host memory given an * index of (A + (256 * SINDEX)) and a base address of SCBID_ADDR. */ post_byte_setup: mov ARG_2, SINDEX; if ((ahc->features & AHC_CMD_CHAN) != 0) { mvi DINDEX, CCHADDR; mvi SCBID_ADDR call set_1byte_addr; mvi CCHCNT, 1; mvi CCSCBCTL, CCSCBRESET ret; } else { mvi DINDEX, HADDR; mvi SCBID_ADDR call set_1byte_addr; mvi HCNT[0], 1; clr HCNT[1]; clr HCNT[2]; mvi DFCNTRL, FIFORESET ret; } post_byte: if ((ahc->features & AHC_CMD_CHAN) != 0) { bmov CCSCBRAM, SINDEX, 1; or CCSCBCTL, CCSCBEN|CCSCBRESET; test CCSCBCTL, CCSCBDONE jz .; clr CCSCBCTL ret; } else { mov DFDAT, SINDEX; or DFCNTRL, HDMAEN|FIFOFLUSH; jmp dma_finish; } get_SCBID_from_host: mov A, SAVED_TCL; mvi UNTAGGEDSCB_OFFSET call fetch_byte; mov RETURN_1, RETURN_2 ret; phase_lock: test SSTAT1, REQINIT jz phase_lock; test SSTAT1, SCSIPERR jnz phase_lock; and SCSISIGO, PHASE_MASK, SCSISIGI; and LASTPHASE, PHASE_MASK, SCSISIGI ret; if ((ahc->features & AHC_CMD_CHAN) == 0) { set_stcnt_from_hcnt: mov STCNT[0], HCNT[0]; mov STCNT[1], HCNT[1]; mov STCNT[2], HCNT[2] ret; bcopy_7: mov DINDIR, SINDIR; mov DINDIR, SINDIR; bcopy_5: mov DINDIR, SINDIR; bcopy_4: mov DINDIR, SINDIR; bcopy_3: mov DINDIR, SINDIR; mov DINDIR, SINDIR; mov DINDIR, SINDIR ret; } if ((ahc->flags & AHC_TARGETMODE) != 0) { /* * Setup addr assuming that A is an index into * an array of 32byte objects, SINDEX contains * the base address of that array, and DINDEX * contains the base address of the location * to store the indexed address. */ set_32byte_addr: shr ARG_2, 3, A; shl A, 5; jmp set_1byte_addr; } /* * Setup addr assuming that A is an index into * an array of 64byte objects, SINDEX contains * the base address of that array, and DINDEX * contains the base address of the location * to store the indexed address. */ set_64byte_addr: shr ARG_2, 2, A; shl A, 6; /* * Setup addr assuming that A + (ARG_1 * 256) is an * index into an array of 1byte objects, SINDEX contains * the base address of that array, and DINDEX contains * the base address of the location to store the computed * address. */ set_1byte_addr: add DINDIR, A, SINDIR; mov A, ARG_2; adc DINDIR, A, SINDIR; clr A; adc DINDIR, A, SINDIR; adc DINDIR, A, SINDIR ret; /* * Either post or fetch and SCB from host memory based on the * DIRECTION bit in DMAPARAMS. The host SCB index is in SINDEX. */ dma_scb: mov A, SINDEX; if ((ahc->features & AHC_CMD_CHAN) != 0) { mvi DINDEX, CCHADDR; mvi HSCB_ADDR call set_64byte_addr; mov CCSCBPTR, SCBPTR; test DMAPARAMS, DIRECTION jz dma_scb_tohost; mvi CCHCNT, SCB_64BYTE_SIZE; mvi CCSCBCTL, CCARREN|CCSCBEN|CCSCBDIR|CCSCBRESET; cmp CCSCBCTL, CCSCBDONE|ARRDONE|CCARREN|CCSCBEN|CCSCBDIR jne .; jmp dma_scb_finish; dma_scb_tohost: mvi CCHCNT, SCB_32BYTE_SIZE; if ((ahc->chip & AHC_CHIPID_MASK) == AHC_AIC7895) { mvi CCSCBCTL, CCSCBRESET; bmov CCSCBRAM, SCB_CONTROL, SCB_32BYTE_SIZE; or CCSCBCTL, CCSCBEN|CCSCBRESET; test CCSCBCTL, CCSCBDONE jz .; } else { mvi CCSCBCTL, CCARREN|CCSCBEN|CCSCBRESET; cmp CCSCBCTL, CCSCBDONE|ARRDONE|CCARREN|CCSCBEN jne .; } dma_scb_finish: clr CCSCBCTL; test CCSCBCTL, CCARREN|CCSCBEN jnz .; ret; } else { mvi DINDEX, HADDR; mvi HSCB_ADDR call set_64byte_addr; mvi HCNT[0], SCB_32BYTE_SIZE; clr HCNT[1]; clr HCNT[2]; mov DFCNTRL, DMAPARAMS; test DMAPARAMS, DIRECTION jnz dma_scb_fromhost; /* Fill it with the SCB data */ copy_scb_tofifo: mvi SINDEX, SCB_CONTROL; add A, SCB_32BYTE_SIZE, SINDEX; copy_scb_tofifo_loop: mov DFDAT,SINDIR; mov DFDAT,SINDIR; mov DFDAT,SINDIR; mov DFDAT,SINDIR; mov DFDAT,SINDIR; mov DFDAT,SINDIR; mov DFDAT,SINDIR; cmp SINDEX, A jne copy_scb_tofifo_loop; or DFCNTRL, HDMAEN|FIFOFLUSH; dma_scb_fromhost: call dma_finish; /* If we were putting the SCB, we are done */ test DMAPARAMS, DIRECTION jz return; mvi SCB_CONTROL call dfdat_in_7; call dfdat_in_7_continued; call dfdat_in_7_continued; jmp dfdat_in_7_continued; dfdat_in_7: mov DINDEX,SINDEX; dfdat_in_7_continued: mov DINDIR,DFDAT; mov DINDIR,DFDAT; mov DINDIR,DFDAT; mov DINDIR,DFDAT; mov DINDIR,DFDAT; mov DINDIR,DFDAT; mov DINDIR,DFDAT ret; } /* * 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 */ and DFCNTRL, ~HDMAEN; test DFCNTRL, HDMAEN jnz .; ret; add_scb_to_free_list: if ((ahc->flags & AHC_PAGESCBS) != 0) { mov SCB_NEXT, FREE_SCBH; mov FREE_SCBH, SCBPTR; } mvi SCB_TAG, SCB_LIST_NULL ret; if ((ahc->flags & AHC_PAGESCBS) != 0) { get_free_or_disc_scb: cmp FREE_SCBH, SCB_LIST_NULL jne dequeue_free_scb; cmp DISCONNECTED_SCBH, SCB_LIST_NULL jne dequeue_disc_scb; return_error: mvi SINDEX, SCB_LIST_NULL ret; dequeue_disc_scb: mov SCBPTR, DISCONNECTED_SCBH; dma_up_scb: mvi DMAPARAMS, FIFORESET; mov SCB_TAG call dma_scb; unlink_disc_scb: mov DISCONNECTED_SCBH, SCB_NEXT ret; dequeue_free_scb: mov SCBPTR, FREE_SCBH; mov FREE_SCBH, SCB_NEXT ret; } add_scb_to_disc_list: /* * 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. */ mov SCB_NEXT, DISCONNECTED_SCBH; mov DISCONNECTED_SCBH, SCBPTR ret;