diff options
Diffstat (limited to 'drivers/scsi/aic7xxx/aic7xxx.seq')
| -rw-r--r-- | drivers/scsi/aic7xxx/aic7xxx.seq | 2398 |
1 files changed, 2398 insertions, 0 deletions
diff --git a/drivers/scsi/aic7xxx/aic7xxx.seq b/drivers/scsi/aic7xxx/aic7xxx.seq new file mode 100644 index 00000000000..d84b741fbab --- /dev/null +++ b/drivers/scsi/aic7xxx/aic7xxx.seq @@ -0,0 +1,2398 @@ +/* + * Adaptec 274x/284x/294x device driver firmware for Linux and FreeBSD. + * + * Copyright (c) 1994-2001 Justin T. Gibbs. + * Copyright (c) 2000-2001 Adaptec Inc. + * 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. + * 2. Redistributions in binary form must reproduce at minimum a disclaimer + * substantially similar to the "NO WARRANTY" disclaimer below + * ("Disclaimer") and any redistribution must be conditioned upon + * including a substantially similar Disclaimer requirement for further + * binary redistribution. + * 3. Neither the names of the above-listed copyright holders nor the names + * of any contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL") version 2 as published by the Free + * Software Foundation. + * + * NO WARRANTY + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES. + * + * $FreeBSD$ + */ + +VERSION = "$Id: //depot/aic7xxx/aic7xxx/aic7xxx.seq#56 $" +PATCH_ARG_LIST = "struct ahc_softc *ahc" +PREFIX = "ahc_" + +#include "aic7xxx.reg" +#include "scsi_message.h" + +/* + * 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. + */ + +bus_free_sel: + /* + * Turn off the selection hardware. We need to reset the + * selection request in order to perform a new selection. + */ + and SCSISEQ, TEMODE|ENSELI|ENRSELI|ENAUTOATNP; + and SIMODE1, ~ENBUSFREE; +poll_for_work: + call clear_target_state; + and SXFRCTL0, ~SPIOEN; + if ((ahc->features & AHC_ULTRA2) != 0) { + clr SCSIBUSL; + } + test SCSISEQ, ENSELO jnz poll_for_selection; + if ((ahc->features & AHC_TWIN) != 0) { + xor SBLKCTL,SELBUSB; /* Toggle to the other bus */ + test SCSISEQ, ENSELO jnz poll_for_selection; + } + cmp WAITING_SCBH,SCB_LIST_NULL jne start_waiting; +poll_for_work_loop: + if ((ahc->features & AHC_TWIN) != 0) { + xor SBLKCTL,SELBUSB; /* Toggle to the other bus */ + } + test SSTAT0, SELDO|SELDI jnz selection; +test_queue: + /* Has the driver posted any work for us? */ +BEGIN_CRITICAL; + if ((ahc->features & AHC_QUEUE_REGS) != 0) { + test QOFF_CTLSTA, SCB_AVAIL jz poll_for_work_loop; + } else { + mov A, QINPOS; + cmp KERNEL_QINPOS, A je poll_for_work_loop; + } + mov ARG_1, NEXT_QUEUED_SCB; + + /* + * We have at least one queued SCB now and we don't have any + * SCBs in the list of SCBs awaiting selection. Allocate a + * card SCB for the host's SCB and get to work on it. + */ + if ((ahc->flags & AHC_PAGESCBS) != 0) { + mov ALLZEROS call get_free_or_disc_scb; + } else { + /* In the non-paging case, the SCBID == hardware SCB index */ + mov SCBPTR, ARG_1; + } + or SEQ_FLAGS2, SCB_DMA; +END_CRITICAL; +dma_queued_scb: + /* + * DMA the SCB from host ram into the current SCB location. + */ + mvi DMAPARAMS, HDMAEN|DIRECTION|FIFORESET; + mov ARG_1 call dma_scb; + /* + * Check one last time to see if this SCB was canceled + * before we completed the DMA operation. If it was, + * the QINFIFO next pointer will not match our saved + * value. + */ + mov A, ARG_1; +BEGIN_CRITICAL; + cmp NEXT_QUEUED_SCB, A jne abort_qinscb; + if ((ahc->flags & AHC_SEQUENCER_DEBUG) != 0) { + cmp SCB_TAG, A je . + 2; + mvi SCB_MISMATCH call set_seqint; + } + mov NEXT_QUEUED_SCB, SCB_NEXT; + mov SCB_NEXT,WAITING_SCBH; + mov WAITING_SCBH, SCBPTR; + if ((ahc->features & AHC_QUEUE_REGS) != 0) { + mov NONE, SNSCB_QOFF; + } else { + inc QINPOS; + } + and SEQ_FLAGS2, ~SCB_DMA; +END_CRITICAL; +start_waiting: + /* + * Start the first entry on the waiting SCB list. + */ + mov SCBPTR, WAITING_SCBH; + call start_selection; + +poll_for_selection: + /* + * Twin channel devices cannot handle things like SELTO + * interrupts on the "background" channel. So, while + * selecting, keep polling the current channel until + * either a selection or reselection occurs. + */ + test SSTAT0, SELDO|SELDI jz poll_for_selection; + +selection: + /* + * We aren't expecting a bus free, so interrupt + * the kernel driver if it happens. + */ + mvi CLRSINT1,CLRBUSFREE; + if ((ahc->features & AHC_DT) == 0) { + or SIMODE1, ENBUSFREE; + } + + /* + * Guard against a bus free after (re)selection + * but prior to enabling the busfree interrupt. SELDI + * and SELDO will be cleared in that case. + */ + test SSTAT0, SELDI|SELDO jz bus_free_sel; + test SSTAT0,SELDO jnz select_out; +select_in: + if ((ahc->flags & AHC_TARGETROLE) != 0) { + if ((ahc->flags & AHC_INITIATORROLE) != 0) { + test SSTAT0, TARGET jz initiator_reselect; + } + mvi CLRSINT0, CLRSELDI; + + /* + * We've just been selected. Assert BSY and + * setup the phase for receiving messages + * from the target. + */ + mvi SCSISIGO, P_MESGOUT|BSYO; + + /* + * Setup the DMA for sending the identify and + * command information. + */ + mvi SEQ_FLAGS, CMDPHASE_PENDING; + + mov A, TQINPOS; + if ((ahc->features & AHC_CMD_CHAN) != 0) { + mvi DINDEX, CCHADDR; + mvi SHARED_DATA_ADDR call set_32byte_addr; + mvi CCSCBCTL, CCSCBRESET; + } else { + mvi DINDEX, HADDR; + mvi SHARED_DATA_ADDR call set_32byte_addr; + mvi DFCNTRL, FIFORESET; + } + + /* Initiator that selected us */ + and SAVED_SCSIID, SELID_MASK, SELID; + /* The Target ID we were selected at */ + if ((ahc->features & AHC_MULTI_TID) != 0) { + and A, OID, TARGIDIN; + } else if ((ahc->features & AHC_ULTRA2) != 0) { + and A, OID, SCSIID_ULTRA2; + } else { + and A, OID, SCSIID; + } + or SAVED_SCSIID, A; + if ((ahc->features & AHC_TWIN) != 0) { + test SBLKCTL, SELBUSB jz . + 2; + or SAVED_SCSIID, TWIN_CHNLB; + } + if ((ahc->features & AHC_CMD_CHAN) != 0) { + mov CCSCBRAM, SAVED_SCSIID; + } else { + mov DFDAT, SAVED_SCSIID; + } + + /* + * If ATN isn't asserted, the target isn't interested + * in talking to us. Go directly to bus free. + * XXX SCSI-1 may require us to assume lun 0 if + * ATN is false. + */ + 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. + */ + 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; + } + and SAVED_LUN, MSG_IDENTIFY_LUNMASK, 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_msg_pending; + add A, -MSG_IGN_WIDE_RESIDUE, DINDEX; + jc ident_messages_done_msg_pending; + + /* 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; + or SEQ_FLAGS, TARGET_CMD_IS_TAGGED; + +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; + test SEQ_FLAGS2, TARGET_MSG_PENDING + jnz target_mesgout_pending; + test SCSISIGI, ATNI jnz target_mesgout_continue; + jmp target_ITloop; + + +ident_messages_done_msg_pending: + or SEQ_FLAGS2, TARGET_MSG_PENDING; + 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 HOST_MSG_LOOP call set_seqint; + cmp RETURN_1, EXIT_MSG_LOOP je target_ITloop; + test SSTAT0, SPIORDY jz .; + jmp host_target_message_loop; + } + +if ((ahc->flags & AHC_INITIATORROLE) != 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 */ + or SXFRCTL0, SPIOEN|CLRSTCNT|CLRCHN; + and SAVED_SCSIID, SELID_MASK, SELID; + if ((ahc->features & AHC_ULTRA2) != 0) { + and A, OID, SCSIID_ULTRA2; + } else { + and A, OID, SCSIID; + } + or SAVED_SCSIID, A; + if ((ahc->features & AHC_TWIN) != 0) { + test SBLKCTL, SELBUSB jz . + 2; + or SAVED_SCSIID, TWIN_CHNLB; + } + mvi CLRSINT0, CLRSELDI; + jmp ITloop; +} + +abort_qinscb: + call add_scb_to_free_list; + jmp poll_for_work_loop; + +start_selection: + /* + * If bus reset interrupts have been disabled (from a previous + * reset), re-enable them now. Resets are only of interest + * when we have outstanding transactions, so we can safely + * defer re-enabling the interrupt until, as an initiator, + * we start sending out transactions again. + */ + test SIMODE1, ENSCSIRST jnz . + 3; + mvi CLRSINT1, CLRSCSIRSTI; + or SIMODE1, ENSCSIRST; + if ((ahc->features & AHC_TWIN) != 0) { + and SINDEX,~SELBUSB,SBLKCTL;/* Clear channel select bit */ + test SCB_SCSIID, TWIN_CHNLB jz . + 2; + or SINDEX, SELBUSB; + mov SBLKCTL,SINDEX; /* select channel */ + } +initialize_scsiid: + if ((ahc->features & AHC_ULTRA2) != 0) { + mov SCSIID_ULTRA2, SCB_SCSIID; + } else if ((ahc->features & AHC_TWIN) != 0) { + and SCSIID, TWIN_TID|OID, SCB_SCSIID; + } else { + mov SCSIID, SCB_SCSIID; + } + if ((ahc->flags & AHC_TARGETROLE) != 0) { + mov SINDEX, SCSISEQ_TEMPLATE; + test SCB_CONTROL, TARGET_SCB jz . + 2; + or SINDEX, TEMODE; + mov SCSISEQ, SINDEX ret; + } else { + mov SCSISEQ, SCSISEQ_TEMPLATE ret; + } + +/* + * Initialize transfer settings with SCB provided settings. + */ +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; + } + +if ((ahc->flags & AHC_TARGETROLE) != 0) { +/* + * 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; +} + +/* + * 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, TEMODE|ENSELI|ENRSELI|ENAUTOATNP, SCSISEQ; + mov SCBPTR, WAITING_SCBH; + mov WAITING_SCBH,SCB_NEXT; + mov SAVED_SCSIID, SCB_SCSIID; + and SAVED_LUN, LID, SCB_LUN; + call set_transfer_settings; + if ((ahc->flags & AHC_TARGETROLE) != 0) { + test SSTAT0, TARGET jz initiator_select; + + or SXFRCTL0, CLRSTCNT|CLRCHN; + + /* + * Put tag in connonical location since not + * all connections have an SCB. + */ + mov INITIATOR_TAG, SCB_TARGET_ITAG; + + /* + * 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 CLRSINT0, CLRSELDO; + + /* + * Start out with a simple identify message. + */ + or SAVED_LUN, 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_TARGET_ITAG call target_outb; +target_synccmd: + /* + * Now determine what phases the host wants us + * to go through. + */ + mov SEQ_FLAGS, SCB_TARGET_PHASES; + + test SCB_CONTROL, MK_MESSAGE jz target_ITloop; + mvi P_MESGIN|BSYO call change_phase; + jmp host_target_message_loop; +target_ITloop: + /* + * Start honoring ATN signals now that + * we properly identified ourselves. + */ + 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; + mvi TARG_IMMEDIATE_SCB, SCB_LIST_NULL; + call complete_target_cmd; + if ((ahc->flags & AHC_PAGESCBS) != 0) { + mov ALLZEROS call get_free_or_disc_scb; + } + cmp TARG_IMMEDIATE_SCB, SCB_LIST_NULL je .; + mvi DMAPARAMS, HDMAEN|DIRECTION|FIFORESET; + mov TARG_IMMEDIATE_SCB call dma_scb; + call set_transfer_settings; + or SXFRCTL0, CLRSTCNT|CLRCHN; + jmp target_synccmd; + +target_mesgout: + mvi SCSISIGO, P_MESGOUT|BSYO; +target_mesgout_continue: + call target_inb; +target_mesgout_pending: + and SEQ_FLAGS2, ~TARGET_MSG_PENDING; + /* Local Processing goes here... */ + 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 preceding I/O session to complete. */ + test SCSISIGI, ACKI jnz .; +target_busfree: + and SIMODE1, ~ENBUSFREE; + if ((ahc->features & AHC_ULTRA2) != 0) { + clr SCSIBUSL; + } + clr SCSISIGO; + mvi LASTPHASE, P_BUSFREE; + call complete_target_cmd; + jmp poll_for_work; + +target_cmdphase: + /* + * The target has dropped ATN (doesn't want to abort or BDR) + * and we believe this selection to be valid. If the ring + * buffer for new commands is full, return busy or queue full. + */ + if ((ahc->features & AHC_HS_MAILBOX) != 0) { + and A, HOST_TQINPOS, HS_MAILBOX; + } else { + mov A, KERNEL_TQINPOS; + } + cmp TQINPOS, A jne tqinfifo_has_space; + mvi P_STATUS|BSYO call change_phase; + test SEQ_FLAGS, TARGET_CMD_IS_TAGGED jz . + 3; + mvi STATUS_QUEUE_FULL call target_outb; + jmp target_busfree_wait; + mvi STATUS_BUSY call target_outb; + jmp target_busfree_wait; +tqinfifo_has_space: + 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, CMDSIZE_TABLE, A; + mov A, SINDIR; + + test A, 0xFF jz command_phase_done; + or SXFRCTL0, SPIOEN; +command_loop: + 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 phases on the bus are from the + * perspective of the initiator. The dma + * code looks at LASTPHASE to determine the + * data direction of the DMA. Toggle it for + * target transfers. + */ + xor LASTPHASE, IOI, SCB_TARGET_DATA_DIR; + or SCB_TARGET_DATA_DIR, BSYO call change_phase; + jmp p_data; + +target_sphase: + mvi P_STATUS|BSYO call change_phase; + mvi LASTPHASE, P_STATUS; + mov SCB_SCSI_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 28 call set_hcnt; + or DFCNTRL, HDMAEN|FIFOFLUSH; + call dma_finish; + } + inc TQINPOS; + mvi INTSTAT,CMDCMPLT ret; + } + +if ((ahc->flags & AHC_INITIATORROLE) != 0) { +initiator_select: + or SXFRCTL0, SPIOEN|CLRSTCNT|CLRCHN; + /* + * 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; + mvi SEQ_FLAGS, NO_CDB_SENT; + mvi CLRSINT0, CLRSELDO; + + /* + * 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. + */ +mesgin_phasemis: +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 BAD_PHASE call set_seqint; + jmp ITloop; /* Try reading the bus again. */ + +await_busfree: + and SIMODE1, ~ENBUSFREE; + mov NONE, SCSIDATL; /* Ack the last byte */ + if ((ahc->features & AHC_ULTRA2) != 0) { + clr SCSIBUSL; /* Prevent bit leakage durint SELTO */ + } + and SXFRCTL0, ~SPIOEN; + test SSTAT1,REQINIT|BUSFREE jz .; + test SSTAT1, BUSFREE jnz poll_for_work; + mvi MISSED_BUSFREE call set_seqint; +} + +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; + or SXFRCTL0, CLRSTCNT|CLRCHN; + + /* + * 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; + if ((ahc->features & AHC_ULTRA) != 0) { + and SXFRCTL0, ~(FAST20); + } + } + mvi LASTPHASE, P_BUSFREE; + /* clear target specific flags */ + mvi SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT ret; + +sg_advance: + clr A; /* add sizeof(struct scatter) */ + add SCB_RESIDUAL_SGPTR[0],SG_SIZEOF; + adc SCB_RESIDUAL_SGPTR[1],A; + adc SCB_RESIDUAL_SGPTR[2],A; + adc SCB_RESIDUAL_SGPTR[3],A ret; + +if ((ahc->features & AHC_CMD_CHAN) != 0) { +disable_ccsgen: + test CCSGCTL, CCSGEN jz return; + test CCSGCTL, CCSGDONE jz .; +disable_ccsgen_fetch_done: + clr CCSGCTL; + test CCSGCTL, CCSGEN jnz .; + ret; +idle_loop: + /* + * Do we need any more segments for this transfer? + */ + test SCB_RESIDUAL_DATACNT[3], SG_LAST_SEG jnz return; + + /* Did we just finish fetching segs? */ + cmp CCSGCTL, CCSGEN|CCSGDONE je idle_sgfetch_complete; + + /* Are we actively fetching segments? */ + test CCSGCTL, CCSGEN jnz return; + + /* + * Do we have any prefetch left??? + */ + cmp CCSGADDR, SG_PREFETCH_CNT jne idle_sg_avail; + + /* + * Need to fetch segments, but we can only do that + * if the command channel is completely idle. Make + * sure we don't have an SCB prefetch going on. + */ + test CCSCBCTL, CCSCBEN jnz return; + + /* + * We fetch a "cacheline aligned" and sized amount of data + * so we don't end up referencing a non-existant page. + * Cacheline aligned is in quotes because the kernel will + * set the prefetch amount to a reasonable level if the + * cacheline size is unknown. + */ + mvi CCHCNT, SG_PREFETCH_CNT; + and CCHADDR[0], SG_PREFETCH_ALIGN_MASK, SCB_RESIDUAL_SGPTR; + bmov CCHADDR[1], SCB_RESIDUAL_SGPTR[1], 3; + mvi CCSGCTL, CCSGEN|CCSGRESET ret; +idle_sgfetch_complete: + call disable_ccsgen_fetch_done; + and CCSGADDR, SG_PREFETCH_ADDR_MASK, SCB_RESIDUAL_SGPTR; +idle_sg_avail: + if ((ahc->features & AHC_ULTRA2) != 0) { + /* Does the hardware have space for another SG entry? */ + test DFSTATUS, PRELOAD_AVAIL jz return; + bmov HADDR, CCSGRAM, 7; + bmov SCB_RESIDUAL_DATACNT[3], CCSGRAM, 1; + if ((ahc->flags & AHC_39BIT_ADDRESSING) != 0) { + mov SCB_RESIDUAL_DATACNT[3] call set_hhaddr; + } + call sg_advance; + mov SINDEX, SCB_RESIDUAL_SGPTR[0]; + test SCB_RESIDUAL_DATACNT[3], SG_LAST_SEG jz . + 2; + or SINDEX, LAST_SEG; + mov SG_CACHE_PRE, SINDEX; + /* Load the segment */ + or DFCNTRL, PRELOADEN; + } + ret; +} + +if ((ahc->bugs & AHC_PCI_MWI_BUG) != 0 && ahc->pci_cachesize != 0) { +/* + * Calculate the trailing portion of this S/G segment that cannot + * be transferred using memory write and invalidate PCI transactions. + * XXX Can we optimize this for PCI writes only??? + */ +calc_mwi_residual: + /* + * If the ending address is on a cacheline boundary, + * there is no need for an extra segment. + */ + mov A, HCNT[0]; + add A, A, HADDR[0]; + and A, CACHESIZE_MASK; + test A, 0xFF jz return; + + /* + * If the transfer is less than a cachline, + * there is no need for an extra segment. + */ + test HCNT[1], 0xFF jnz calc_mwi_residual_final; + test HCNT[2], 0xFF jnz calc_mwi_residual_final; + add NONE, INVERTED_CACHESIZE_MASK, HCNT[0]; + jnc return; + +calc_mwi_residual_final: + mov MWI_RESIDUAL, A; + not A; + inc A; + add HCNT[0], A; + adc HCNT[1], -1; + adc HCNT[2], -1 ret; +} + +p_data: + test SEQ_FLAGS,NOT_IDENTIFIED|NO_CDB_SENT jz p_data_allowed; + mvi PROTO_VIOLATION call set_seqint; +p_data_allowed: + 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; + if ((ahc->features & AHC_CMD_CHAN) != 0) { + /* We don't have any valid S/G elements */ + mvi CCSGADDR, SG_PREFETCH_CNT; + } + test SEQ_FLAGS, DPHASE jz data_phase_initialize; + + /* + * If we re-enter the data phase after going through another + * phase, our transfer location has almost certainly been + * corrupted by the interveining, non-data, transfers. Ask + * the host driver to fix us up based on the transfer residual. + */ + mvi PDATA_REINIT call set_seqint; + jmp data_phase_loop; + +data_phase_initialize: + /* We have seen a data phase for the first time */ + or SEQ_FLAGS, DPHASE; + + /* + * Initialize the DMA address and counter from the SCB. + * Also set SCB_RESIDUAL_SGPTR, including the LAST_SEG + * flag in the highest byte of the data count. We cannot + * modify the saved values in the SCB until we see a save + * data pointers message. + */ + if ((ahc->flags & AHC_39BIT_ADDRESSING) != 0) { + /* The lowest address byte must be loaded last. */ + mov SCB_DATACNT[3] call set_hhaddr; + } + if ((ahc->features & AHC_CMD_CHAN) != 0) { + bmov HADDR, SCB_DATAPTR, 7; + bmov SCB_RESIDUAL_DATACNT[3], SCB_DATACNT[3], 5; + } else { + mvi DINDEX, HADDR; + mvi SCB_DATAPTR call bcopy_7; + mvi DINDEX, SCB_RESIDUAL_DATACNT + 3; + mvi SCB_DATACNT + 3 call bcopy_5; + } + if ((ahc->bugs & AHC_PCI_MWI_BUG) != 0 && ahc->pci_cachesize != 0) { + call calc_mwi_residual; + } + and SCB_RESIDUAL_SGPTR[0], ~SG_FULL_RESID; + + if ((ahc->features & AHC_ULTRA2) == 0) { + if ((ahc->features & AHC_CMD_CHAN) != 0) { + bmov STCNT, HCNT, 3; + } else { + call set_stcnt_from_hcnt; + } + } + +data_phase_loop: + /* Guard against overruns */ + test SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jz data_phase_inbounds; + + /* + * Turn on `Bit Bucket' mode, wait until the target takes + * us to another phase, and then notify the host. + */ + and DMAPARAMS, DIRECTION; + mov DFCNTRL, DMAPARAMS; + or SXFRCTL1,BITBUCKET; + if ((ahc->features & AHC_DT) == 0) { + test SSTAT1,PHASEMIS jz .; + } else { + test SCSIPHASE, DATA_PHASE_MASK jnz .; + } + and SXFRCTL1, ~BITBUCKET; + mvi DATA_OVERRUN call set_seqint; + jmp ITloop; + +data_phase_inbounds: + if ((ahc->features & AHC_ULTRA2) != 0) { + mov SINDEX, SCB_RESIDUAL_SGPTR[0]; + test SCB_RESIDUAL_DATACNT[3], SG_LAST_SEG jz . + 2; + or SINDEX, LAST_SEG; + mov SG_CACHE_PRE, SINDEX; + mov DFCNTRL, DMAPARAMS; +ultra2_dma_loop: + call idle_loop; + /* + * The transfer is complete if either the last segment + * completes or the target changes phase. + */ + test SG_CACHE_SHADOW, LAST_SEG_DONE jnz ultra2_dmafinish; + if ((ahc->features & AHC_DT) == 0) { + if ((ahc->flags & AHC_TARGETROLE) != 0) { + /* + * As a target, we control the phases, + * so ignore PHASEMIS. + */ + test SSTAT0, TARGET jnz ultra2_dma_loop; + } + if ((ahc->flags & AHC_INITIATORROLE) != 0) { + test SSTAT1,PHASEMIS jz ultra2_dma_loop; + } + } else { + test DFCNTRL, SCSIEN jnz ultra2_dma_loop; + } + +ultra2_dmafinish: + /* + * The transfer has terminated either due to a phase + * change, and/or the completion of the last segment. + * We have two goals here. Do as much other work + * as possible while the data fifo drains on a read + * and respond as quickly as possible to the standard + * messages (save data pointers/disconnect and command + * complete) that usually follow a data phase. + */ + if ((ahc->bugs & AHC_AUTOFLUSH_BUG) != 0) { + /* + * On chips with broken auto-flush, start + * the flushing process now. We'll poke + * the chip from time to time to keep the + * flush process going as we complete the + * data phase. + */ + or DFCNTRL, FIFOFLUSH; + } + /* + * We assume that, even though data may still be + * transferring to the host, that the SCSI side of + * the DMA engine is now in a static state. This + * allows us to update our notion of where we are + * in this transfer. + * + * If, by chance, we stopped before being able + * to fetch additional segments for this transfer, + * yet the last S/G was completely exhausted, + * call our idle loop until it is able to load + * another segment. This will allow us to immediately + * pickup on the next segment on the next data phase. + * + * If we happened to stop on the last segment, then + * our residual information is still correct from + * the idle loop and there is no need to perform + * any fixups. + */ +ultra2_ensure_sg: + test SG_CACHE_SHADOW, LAST_SEG jz ultra2_shvalid; + /* Record if we've consumed all S/G entries */ + test SSTAT2, SHVALID jnz residuals_correct; + or SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL; + jmp residuals_correct; + +ultra2_shvalid: + test SSTAT2, SHVALID jnz sgptr_fixup; + call idle_loop; + jmp ultra2_ensure_sg; + +sgptr_fixup: + /* + * Fixup the residual next S/G pointer. The S/G preload + * feature of the chip allows us to load two elements + * in addition to the currently active element. We + * store the bottom byte of the next S/G pointer in + * the SG_CACEPTR register so we can restore the + * correct value when the DMA completes. If the next + * sg ptr value has advanced to the point where higher + * bytes in the address have been affected, fix them + * too. + */ + test SG_CACHE_SHADOW, 0x80 jz sgptr_fixup_done; + test SCB_RESIDUAL_SGPTR[0], 0x80 jnz sgptr_fixup_done; + add SCB_RESIDUAL_SGPTR[1], -1; + adc SCB_RESIDUAL_SGPTR[2], -1; + adc SCB_RESIDUAL_SGPTR[3], -1; +sgptr_fixup_done: + and SCB_RESIDUAL_SGPTR[0], SG_ADDR_MASK, SG_CACHE_SHADOW; + /* We are not the last seg */ + and SCB_RESIDUAL_DATACNT[3], ~SG_LAST_SEG; +residuals_correct: + /* + * Go ahead and shut down the DMA engine now. + * In the future, we'll want to handle end of + * transfer messages prior to doing this, but this + * requires similar restructuring for pre-ULTRA2 + * controllers. + */ + test DMAPARAMS, DIRECTION jnz ultra2_fifoempty; +ultra2_fifoflush: + if ((ahc->features & AHC_DT) == 0) { + if ((ahc->bugs & AHC_AUTOFLUSH_BUG) != 0) { + /* + * On Rev A of the aic7890, the autoflush + * feature doesn't function correctly. + * Perform an explicit manual flush. During + * a manual flush, the FIFOEMP bit becomes + * true every time the PCI FIFO empties + * regardless of the state of the SCSI FIFO. + * It can take up to 4 clock cycles for the + * SCSI FIFO to get data into the PCI FIFO + * and for FIFOEMP to de-assert. Here we + * guard against this condition by making + * sure the FIFOEMP bit stays on for 5 full + * clock cycles. + */ + or DFCNTRL, FIFOFLUSH; + test DFSTATUS, FIFOEMP jz ultra2_fifoflush; + test DFSTATUS, FIFOEMP jz ultra2_fifoflush; + test DFSTATUS, FIFOEMP jz ultra2_fifoflush; + test DFSTATUS, FIFOEMP jz ultra2_fifoflush; + } + test DFSTATUS, FIFOEMP jz ultra2_fifoflush; + } else { + /* + * We enable the auto-ack feature on DT capable + * controllers. This means that the controller may + * have already transferred some overrun bytes into + * the data FIFO and acked them on the bus. The only + * way to detect this situation is to wait for + * LAST_SEG_DONE to come true on a completed transfer + * and then test to see if the data FIFO is non-empty. + */ + test SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL + jz ultra2_wait_fifoemp; + test SG_CACHE_SHADOW, LAST_SEG_DONE jz .; + /* + * FIFOEMP can lag LAST_SEG_DONE. Wait a few + * clocks before calling this an overrun. + */ + test DFSTATUS, FIFOEMP jnz ultra2_fifoempty; + test DFSTATUS, FIFOEMP jnz ultra2_fifoempty; + test DFSTATUS, FIFOEMP jnz ultra2_fifoempty; + /* Overrun */ + jmp data_phase_loop; +ultra2_wait_fifoemp: + test DFSTATUS, FIFOEMP jz .; + } +ultra2_fifoempty: + /* Don't clobber an inprogress host data transfer */ + test DFSTATUS, MREQPEND jnz ultra2_fifoempty; +ultra2_dmahalt: + and DFCNTRL, ~(SCSIEN|HDMAEN); + test DFCNTRL, SCSIEN|HDMAEN jnz .; + if ((ahc->flags & AHC_39BIT_ADDRESSING) != 0) { + /* + * Keep HHADDR cleared for future, 32bit addressed + * only, DMA operations. + * + * Due to bayonette style S/G handling, our residual + * data must be "fixed up" once the transfer is halted. + * Here we fixup the HSHADDR stored in the high byte + * of the residual data cnt. By postponing the fixup, + * we can batch the clearing of HADDR with the fixup. + * If we halted on the last segment, the residual is + * already correct. If we are not on the last + * segment, copy the high address directly from HSHADDR. + * We don't need to worry about maintaining the + * SG_LAST_SEG flag as it will always be false in the + * case where an update is required. + */ + or DSCOMMAND1, HADDLDSEL0; + test SG_CACHE_SHADOW, LAST_SEG jnz . + 2; + mov SCB_RESIDUAL_DATACNT[3], SHADDR; + clr HADDR; + and DSCOMMAND1, ~HADDLDSEL0; + } + } else { + /* If we are the last SG block, tell the hardware. */ + if ((ahc->bugs & AHC_PCI_MWI_BUG) != 0 + && ahc->pci_cachesize != 0) { + test MWI_RESIDUAL, 0xFF jnz dma_mid_sg; + } + test SCB_RESIDUAL_DATACNT[3], SG_LAST_SEG jz dma_mid_sg; + if ((ahc->flags & AHC_TARGETROLE) != 0) { + test SSTAT0, TARGET jz dma_last_sg; + if ((ahc->flags & AHC_TMODE_WIDEODD_BUG) != 0) { + test DMAPARAMS, DIRECTION jz dma_mid_sg; + } + } +dma_last_sg: + and DMAPARAMS, ~WIDEODD; +dma_mid_sg: + /* Start DMA data transfer. */ + mov DFCNTRL, DMAPARAMS; +dma_loop: + if ((ahc->features & AHC_CMD_CHAN) != 0) { + call idle_loop; + } + test SSTAT0,DMADONE jnz dma_dmadone; + test SSTAT1,PHASEMIS jz dma_loop; /* ie. underrun */ +dma_phasemis: + /* + * 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 off the DMA and make sure that the DMA + * hardware has actually stopped. Touching the DMA + * counters, etc. while a DMA is active will result + * in an ILLSADDR exception. + */ +dma_dmadone: + and DFCNTRL, ~(SCSIEN|SDMAEN|HDMAEN); +dma_halt: + /* + * Some revisions of the aic78XX 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 drain + * the prefetched but unused data from the data fifo until + * there is space for the input latch to drain. + */ + if ((ahc->bugs & AHC_PCI_2_1_RETRY_BUG) != 0) { + mov NONE, DFDAT; + } + test DFCNTRL, (SCSIEN|SDMAEN|HDMAEN) jnz dma_halt; + + /* See if we have completed this last segment */ + test STCNT[0], 0xff jnz data_phase_finish; + test STCNT[1], 0xff jnz data_phase_finish; + test STCNT[2], 0xff jnz data_phase_finish; + + /* + * Advance the scatter-gather pointers if needed + */ + if ((ahc->bugs & AHC_PCI_MWI_BUG) != 0 + && ahc->pci_cachesize != 0) { + test MWI_RESIDUAL, 0xFF jz no_mwi_resid; + /* + * Reload HADDR from SHADDR and setup the + * count to be the size of our residual. + */ + if ((ahc->features & AHC_CMD_CHAN) != 0) { + bmov HADDR, SHADDR, 4; + mov HCNT, MWI_RESIDUAL; + bmov HCNT[1], ALLZEROS, 2; + } else { + mvi DINDEX, HADDR; + mvi SHADDR call bcopy_4; + mov MWI_RESIDUAL call set_hcnt; + } + clr MWI_RESIDUAL; + jmp sg_load_done; +no_mwi_resid: + } + test SCB_RESIDUAL_DATACNT[3], SG_LAST_SEG jz sg_load; + or SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL; + jmp data_phase_finish; +sg_load: + /* + * Load the next SG element's data address and length + * into the DMA engine. If we don't have hardware + * to perform a prefetch, we'll have to fetch the + * segment from host memory first. + */ + if ((ahc->features & AHC_CMD_CHAN) != 0) { + /* Wait for the idle loop to complete */ + test CCSGCTL, CCSGEN jz . + 3; + call idle_loop; + test CCSGCTL, CCSGEN jnz . - 1; + bmov HADDR, CCSGRAM, 7; + /* + * Workaround for flaky external SCB RAM + * on certain aic7895 setups. It seems + * unable to handle direct transfers from + * S/G ram to certain SCB locations. + */ + mov SINDEX, CCSGRAM; + mov SCB_RESIDUAL_DATACNT[3], SINDEX; + } else { + if ((ahc->flags & AHC_39BIT_ADDRESSING) != 0) { + mov ALLZEROS call set_hhaddr; + } + mvi DINDEX, HADDR; + mvi SCB_RESIDUAL_SGPTR call bcopy_4; + + mvi SG_SIZEOF call set_hcnt; + + or DFCNTRL, HDMAEN|DIRECTION|FIFORESET; + + call dma_finish; + + mvi DINDEX, HADDR; + call dfdat_in_7; + mov SCB_RESIDUAL_DATACNT[3], DFDAT; + } + + if ((ahc->flags & AHC_39BIT_ADDRESSING) != 0) { + mov SCB_RESIDUAL_DATACNT[3] call set_hhaddr; + + /* + * The lowest address byte must be loaded + * last as it triggers the computation of + * some items in the PCI block. The ULTRA2 + * chips do this on PRELOAD. + */ + mov HADDR, HADDR; + } + if ((ahc->bugs & AHC_PCI_MWI_BUG) != 0 + && ahc->pci_cachesize != 0) { + call calc_mwi_residual; + } + + /* Point to the new next sg in memory */ + call sg_advance; + +sg_load_done: + if ((ahc->features & AHC_CMD_CHAN) != 0) { + bmov STCNT, HCNT, 3; + } else { + call set_stcnt_from_hcnt; + } + + if ((ahc->flags & AHC_TARGETROLE) != 0) { + test SSTAT0, TARGET jnz data_phase_loop; + } + } +data_phase_finish: + /* + * If the target has left us in data phase, loop through + * the dma code again. In the case of ULTRA2 adapters, + * we should only loop if there is a data overrun. For + * all other adapters, we'll loop after each S/G element + * is loaded as well as if there is an overrun. + */ + if ((ahc->flags & AHC_TARGETROLE) != 0) { + test SSTAT0, TARGET jnz data_phase_done; + } + if ((ahc->flags & AHC_INITIATORROLE) != 0) { + test SSTAT1, REQINIT jz .; + if ((ahc->features & AHC_DT) == 0) { + test SSTAT1,PHASEMIS jz data_phase_loop; + } else { + test SCSIPHASE, DATA_PHASE_MASK jnz data_phase_loop; + } + } + +data_phase_done: + /* + * 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) { + /* Kill off any pending prefetch */ + call disable_ccsgen; + } + + if ((ahc->features & AHC_ULTRA2) == 0) { + /* + * Clear the high address byte so that all other DMA + * operations, which use 32bit addressing, can assume + * HHADDR is 0. + */ + if ((ahc->flags & AHC_39BIT_ADDRESSING) != 0) { + mov ALLZEROS call set_hhaddr; + } + } + + /* + * Update our residual information before the information is + * lost by some other type of SCSI I/O (e.g. PIO). If we have + * transferred all data, no update is needed. + * + */ + test SCB_RESIDUAL_SGPTR, SG_LIST_NULL jnz residual_update_done; + if ((ahc->bugs & AHC_PCI_MWI_BUG) != 0 + && ahc->pci_cachesize != 0) { + if ((ahc->features & AHC_CMD_CHAN) != 0) { + test MWI_RESIDUAL, 0xFF jz bmov_resid; + } + mov A, MWI_RESIDUAL; + add SCB_RESIDUAL_DATACNT[0], A, STCNT[0]; + clr A; + adc SCB_RESIDUAL_DATACNT[1], A, STCNT[1]; + adc SCB_RESIDUAL_DATACNT[2], A, STCNT[2]; + clr MWI_RESIDUAL; + if ((ahc->features & AHC_CMD_CHAN) != 0) { + jmp . + 2; +bmov_resid: + bmov SCB_RESIDUAL_DATACNT, STCNT, 3; + } + } else if ((ahc->features & AHC_CMD_CHAN) != 0) { + bmov SCB_RESIDUAL_DATACNT, STCNT, 3; + } else { + mov SCB_RESIDUAL_DATACNT[0], STCNT[0]; + mov SCB_RESIDUAL_DATACNT[1], STCNT[1]; + mov SCB_RESIDUAL_DATACNT[2], STCNT[2]; + } +residual_update_done: + /* + * Since we've been through a data phase, the SCB_RESID* fields + * are now initialized. Clear the full residual flag. + */ + and SCB_SGPTR[0], ~SG_FULL_RESID; + + if ((ahc->features & AHC_ULTRA2) != 0) { + /* Clear the channel in case we return to data phase later */ + or SXFRCTL0, CLRSTCNT|CLRCHN; + or SXFRCTL0, CLRSTCNT|CLRCHN; + } + + if ((ahc->flags & AHC_TARGETROLE) != 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. We only need to + * send Ignore Wide Residue messages for data-in phases. + */ + test DFCNTRL, DIRECTION jz target_ITloop; + test SSTAT1, REQINIT jnz .; + test SCB_LUN, SCB_XFERLEN_ODD jz target_ITloop; + test SCSIRATE, WIDEXFER jz target_ITloop; + /* + * Issue an Ignore Wide Residue Message. + */ + mvi P_MESGIN|BSYO call change_phase; + mvi MSG_IGN_WIDE_RESIDUE call target_outb; + mvi 1 call target_outb; + jmp target_ITloop; + } else { + jmp ITloop; + } + +if ((ahc->flags & AHC_INITIATORROLE) != 0) { +/* + * Command phase. Set up the DMA registers and let 'er rip. + */ +p_command: + test SEQ_FLAGS, NOT_IDENTIFIED jz p_command_okay; + mvi PROTO_VIOLATION call set_seqint; +p_command_okay: + + if ((ahc->features & AHC_ULTRA2) != 0) { + bmov HCNT[0], SCB_CDB_LEN, 1; + bmov HCNT[1], ALLZEROS, 2; + mvi SG_CACHE_PRE, LAST_SEG; + } else if ((ahc->features & AHC_CMD_CHAN) != 0) { + bmov STCNT[0], SCB_CDB_LEN, 1; + bmov STCNT[1], ALLZEROS, 2; + } else { + mov STCNT[0], SCB_CDB_LEN; + clr STCNT[1]; + clr STCNT[2]; + } + add NONE, -13, SCB_CDB_LEN; + mvi SCB_CDB_STORE jnc p_command_embedded; +p_command_from_host: + if ((ahc->features & AHC_ULTRA2) != 0) { + bmov HADDR[0], SCB_CDB_PTR, 4; + mvi DFCNTRL, (PRELOADEN|SCSIEN|HDMAEN|DIRECTION); + } else { + if ((ahc->features & AHC_CMD_CHAN) != 0) { + bmov HADDR[0], SCB_CDB_PTR, 4; + bmov HCNT, STCNT, 3; + } else { + mvi DINDEX, HADDR; + mvi SCB_CDB_PTR call bcopy_4; + mov SCB_CDB_LEN call set_hcnt; + } + mvi DFCNTRL, (SCSIEN|SDMAEN|HDMAEN|DIRECTION|FIFORESET); + } + jmp p_command_xfer; +p_command_embedded: + /* + * The data fifo seems to require 4 byte aligned + * transfers from the sequencer. Force this to + * be the case by clearing HADDR[0] even though + * we aren't going to touch host memory. + */ + clr HADDR[0]; + if ((ahc->features & AHC_ULTRA2) != 0) { + mvi DFCNTRL, (PRELOADEN|SCSIEN|DIRECTION); + bmov DFDAT, SCB_CDB_STORE, 12; + } else if ((ahc->features & AHC_CMD_CHAN) != 0) { + if ((ahc->flags & AHC_SCB_BTT) != 0) { + /* + * On the 7895 the data FIFO will + * get corrupted if you try to dump + * data from external SCB memory into + * the FIFO while it is enabled. So, + * fill the fifo and then enable SCSI + * transfers. + */ + mvi DFCNTRL, (DIRECTION|FIFORESET); + } else { + mvi DFCNTRL, (SCSIEN|SDMAEN|DIRECTION|FIFORESET); + } + bmov DFDAT, SCB_CDB_STORE, 12; + if ((ahc->flags & AHC_SCB_BTT) != 0) { + mvi DFCNTRL, (SCSIEN|SDMAEN|DIRECTION|FIFOFLUSH); + } else { + or DFCNTRL, FIFOFLUSH; + } + } else { + mvi DFCNTRL, (SCSIEN|SDMAEN|DIRECTION|FIFORESET); + call copy_to_fifo_6; + call copy_to_fifo_6; + or DFCNTRL, FIFOFLUSH; + } +p_command_xfer: + and SEQ_FLAGS, ~NO_CDB_SENT; + if ((ahc->features & AHC_DT) == 0) { + test SSTAT0, SDONE jnz . + 2; + test SSTAT1, PHASEMIS jz . - 1; + /* + * Wait for our ACK to go-away on it's own + * instead of being killed by SCSIEN getting cleared. + */ + test SCSISIGI, ACKI jnz .; + } else { + test DFCNTRL, SCSIEN jnz .; + } + test SSTAT0, SDONE jnz p_command_successful; + /* + * Don't allow a data phase if the command + * was not fully transferred. + */ + or SEQ_FLAGS, NO_CDB_SENT; +p_command_successful: + and DFCNTRL, ~(SCSIEN|SDMAEN|HDMAEN); + 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: + test SEQ_FLAGS, NOT_IDENTIFIED jnz mesgin_proto_violation; +p_status_okay: + mov SCB_SCSI_STATUS, SCSIDATL; + or SCB_CONTROL, STATUS_RCVD; + 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: + /* Turn on ATN for the retry */ + if ((ahc->features & AHC_DT) == 0) { + or SCSISIGO, ATNO, LASTPHASE; + } else { + mvi SCSISIGO, ATNO; + } +p_mesgout: + mov SINDEX, MSG_OUT; + cmp SINDEX, MSG_IDENTIFYFLAG jne p_mesgout_from_host; + test SCB_CONTROL,MK_MESSAGE jnz host_message_loop; +p_mesgout_identify: + or SINDEX, MSG_IDENTIFYFLAG|DISCENB, SAVED_LUN; + test SCB_CONTROL, DISCENB jnz . + 2; + and SINDEX, ~DISCENB; +/* + * 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_IGN_WIDE_RESIDUE je mesgin_ign_wide_residue; + 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 HOST_MSG_LOOP call set_seqint; + call phase_lock; + cmp RETURN_1, EXIT_MSG_LOOP je ITloop + 1; + jmp host_message_loop; + +mesgin_ign_wide_residue: +if ((ahc->features & AHC_WIDE) != 0) { + test SCSIRATE, WIDEXFER jz mesgin_reject; + /* Pull the residue byte */ + mvi ARG_1 call inb_next; + cmp ARG_1, 0x01 jne mesgin_reject; + test SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jz . + 2; + test SCB_LUN, SCB_XFERLEN_ODD jnz mesgin_done; + mvi IGN_WIDE_RES call set_seqint; + jmp mesgin_done; +} + +mesgin_proto_violation: + mvi PROTO_VIOLATION call set_seqint; + jmp mesgin_done; +mesgin_reject: + mvi MSG_MESSAGE_REJECT call mk_mesg; +mesgin_done: + mov NONE,SCSIDATL; /*dummy read from latch to ACK*/ + jmp ITloop; + +/* + * We received a "command complete" message. 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, requeue + * it to the QINFIFO and tell us not to post to the QOUTFIFO by setting + * RETURN_1 to SEND_SENSE. + */ +mesgin_complete: + + /* + * If ATN is raised, we still want to give the target a message. + * Perhaps there was a parity error on this last message byte. + * Either way, the target should take us to message out phase + * and then attempt to complete the command again. We should use a + * critical section here to guard against a timeout triggering + * for this command and setting ATN while we are still processing + * the completion. + test SCSISIGI, ATNI jnz mesgin_done; + */ + + /* + * If we are identified and have successfully sent the CDB, + * any status will do. Optimize this fast path. + */ + test SCB_CONTROL, STATUS_RCVD jz mesgin_proto_violation; + test SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT jz complete_accepted; + + /* + * If the target never sent an identify message but instead went + * to mesgin to give an invalid message, let the host abort us. + */ + test SEQ_FLAGS, NOT_IDENTIFIED jnz mesgin_proto_violation; + + /* + * If we recevied good status but never successfully sent the + * cdb, abort the command. + */ + test SCB_SCSI_STATUS,0xff jnz complete_accepted; + test SEQ_FLAGS, NO_CDB_SENT jnz mesgin_proto_violation; + +complete_accepted: + /* + * See if we attempted to deliver a message but the target ingnored us. + */ + test SCB_CONTROL, MK_MESSAGE jz . + 2; + mvi MKMSG_FAILED call set_seqint; + + /* + * Check for residuals + */ + test SCB_SGPTR, SG_LIST_NULL jnz check_status;/* No xfer */ + test SCB_SGPTR, SG_FULL_RESID jnz upload_scb;/* Never xfered */ + test SCB_RESIDUAL_SGPTR, SG_LIST_NULL jz upload_scb; +check_status: + test SCB_SCSI_STATUS,0xff jz complete; /* Good Status? */ +upload_scb: + or SCB_SGPTR, SG_RESID_VALID; + mvi DMAPARAMS, FIFORESET; + mov SCB_TAG call dma_scb; + test SCB_SCSI_STATUS, 0xff jz complete; /* Just a residual? */ + mvi BAD_STATUS call set_seqint; /* let driver know */ + cmp RETURN_1, SEND_SENSE jne complete; + call add_scb_to_free_list; + jmp await_busfree; +complete: + mov SCB_TAG call complete_post; + jmp await_busfree; +} + +complete_post: + /* Post the SCBID in SINDEX and issue an interrupt */ + call add_scb_to_free_list; + 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_INITIATORROLE) != 0) { +/* + * Is it a disconnect message? Set a flag in the SCB to remind us + * and await the bus going free. If this is an untagged transaction + * store the SCB id for it in our untagged target table for lookup on + * a reselction. + */ +mesgin_disconnect: + /* + * If ATN is raised, we still want to give the target a message. + * Perhaps there was a parity error on this last message byte + * or we want to abort this command. Either way, the target + * should take us to message out phase and then attempt to + * disconnect again. + * XXX - Wait for more testing. + test SCSISIGI, ATNI jnz mesgin_done; + */ + test SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT + jnz mesgin_proto_violation; + or SCB_CONTROL,DISCONNECTED; + if ((ahc->flags & AHC_PAGESCBS) != 0) { + call add_scb_to_disc_list; + } + test SCB_CONTROL, TAG_ENB jnz await_busfree; + mov ARG_1, SCB_TAG; + and SAVED_LUN, LID, SCB_LUN; + mov SCB_SCSIID call set_busy_target; + 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. + * Ack the message as soon as possible. For chips without S/G pipelining, + * we can only ack the message after SHADDR has been saved. On these + * chips, SHADDR increments with every bus transaction, even PIO. + */ +mesgin_sdptrs: + if ((ahc->features & AHC_ULTRA2) != 0) { + mov NONE,SCSIDATL; /*dummy read from latch to ACK*/ + test SEQ_FLAGS, DPHASE jz ITloop; + } else { + test SEQ_FLAGS, DPHASE jz mesgin_done; + } + + /* + * If we are asked to save our position at the end of the + * transfer, just mark us at the end rather than perform a + * full save. + */ + test SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jz mesgin_sdptrs_full; + or SCB_SGPTR, SG_LIST_NULL; + if ((ahc->features & AHC_ULTRA2) != 0) { + jmp ITloop; + } else { + jmp mesgin_done; + } + +mesgin_sdptrs_full: + + /* + * 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_DATAPTR, SHADDR, 4; + if ((ahc->features & AHC_ULTRA2) == 0) { + mov NONE,SCSIDATL; /*dummy read from latch to ACK*/ + } + bmov SCB_DATACNT, SCB_RESIDUAL_DATACNT, 8; + } else { + mvi DINDEX, SCB_DATAPTR; + mvi SHADDR call bcopy_4; + mov NONE,SCSIDATL; /*dummy read from latch to ACK*/ + mvi SCB_RESIDUAL_DATACNT call bcopy_8; + } + jmp ITloop; + +/* + * 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. We also reset/reallocate the FIFO to make + * sure we have a clean start for the next data or command phase. + */ +mesgin_rdptrs: + and SEQ_FLAGS, ~DPHASE; /* + * We'll reload them + * the next time through + * the dataphase. + */ + or SXFRCTL0, CLRSTCNT|CLRCHN; + jmp mesgin_done; + +/* + * Index into our Busy Target table. SINDEX and DINDEX are modified + * upon return. SCBPTR may be modified by this action. + */ +set_busy_target: + shr DINDEX, 4, SINDEX; + if ((ahc->flags & AHC_SCB_BTT) != 0) { + mov SCBPTR, SAVED_LUN; + add DINDEX, SCB_64_BTT; + } else { + add DINDEX, BUSY_TARGETS; + } + mov DINDIR, ARG_1 ret; + +/* + * 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: + /* + * Determine whether a target is using tagged or non-tagged + * transactions by first looking at the transaction stored in + * the busy target array. If there is no untagged transaction + * for this target or the transaction is for a different lun, then + * this must be a tagged transaction. + */ + shr SINDEX, 4, SAVED_SCSIID; + and SAVED_LUN, MSG_IDENTIFY_LUNMASK, A; + if ((ahc->flags & AHC_SCB_BTT) != 0) { + add SINDEX, SCB_64_BTT; + mov SCBPTR, SAVED_LUN; + if ((ahc->flags & AHC_SEQUENCER_DEBUG) != 0) { + add NONE, -SCB_64_BTT, SINDEX; + jc . + 2; + mvi INTSTAT, OUT_OF_RANGE; + nop; + add NONE, -(SCB_64_BTT + 16), SINDEX; + jnc . + 2; + mvi INTSTAT, OUT_OF_RANGE; + nop; + } + } else { + add SINDEX, BUSY_TARGETS; + if ((ahc->flags & AHC_SEQUENCER_DEBUG) != 0) { + add NONE, -BUSY_TARGETS, SINDEX; + jc . + 2; + mvi INTSTAT, OUT_OF_RANGE; + nop; + add NONE, -(BUSY_TARGETS + 16), SINDEX; + jnc . + 2; + mvi INTSTAT, OUT_OF_RANGE; + nop; + } + } + mov ARG_1, SINDIR; + cmp ARG_1, SCB_LIST_NULL je snoop_tag; + if ((ahc->flags & AHC_PAGESCBS) != 0) { + mov ARG_1 call findSCB; + } else { + mov SCBPTR, ARG_1; + } + if ((ahc->flags & AHC_SCB_BTT) != 0) { + jmp setup_SCB_id_lun_okay; + } else { + /* + * We only allow one untagged command per-target + * at a time. So, if the lun doesn't match, look + * for a tag message. + */ + and A, LID, SCB_LUN; + cmp SAVED_LUN, A je setup_SCB_id_lun_okay; + if ((ahc->flags & AHC_PAGESCBS) != 0) { + /* + * findSCB removes the SCB from the + * disconnected list, so we must replace + * it there should this SCB be for another + * lun. + */ + call cleanup_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, we must search for 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: + if ((ahc->flags & AHC_SEQUENCER_DEBUG) != 0) { + or SEQ_FLAGS, 0x80; + } + mov NONE,SCSIDATL; /* ACK Identify MSG */ + call phase_lock; + if ((ahc->flags & AHC_SEQUENCER_DEBUG) != 0) { + or SEQ_FLAGS, 0x1; + } + cmp LASTPHASE, P_MESGIN jne not_found; + if ((ahc->flags & AHC_SEQUENCER_DEBUG) != 0) { + or SEQ_FLAGS, 0x2; + } + cmp SCSIBUSL,MSG_SIMPLE_Q_TAG jne not_found; +get_tag: + if ((ahc->flags & AHC_PAGESCBS) != 0) { + mvi ARG_1 call inb_next; /* tag value */ + mov ARG_1 call findSCB; + } else { + mvi ARG_1 call inb_next; /* tag value */ + mov SCBPTR, ARG_1; + } + +/* + * Ensure that the SCB the tag points to is for + * an SCB transaction to the reconnecting target. + */ +setup_SCB: + if ((ahc->flags & AHC_SEQUENCER_DEBUG) != 0) { + or SEQ_FLAGS, 0x4; + } + mov A, SCB_SCSIID; + cmp SAVED_SCSIID, A jne not_found_cleanup_scb; + if ((ahc->flags & AHC_SEQUENCER_DEBUG) != 0) { + or SEQ_FLAGS, 0x8; + } +setup_SCB_id_okay: + and A, LID, SCB_LUN; + cmp SAVED_LUN, A jne not_found_cleanup_scb; +setup_SCB_id_lun_okay: + if ((ahc->flags & AHC_SEQUENCER_DEBUG) != 0) { + or SEQ_FLAGS, 0x10; + } + test SCB_CONTROL,DISCONNECTED jz not_found_cleanup_scb; + and SCB_CONTROL,~DISCONNECTED; + test SCB_CONTROL, TAG_ENB jnz setup_SCB_tagged; + if ((ahc->flags & AHC_SCB_BTT) != 0) { + mov A, SCBPTR; + } + mvi ARG_1, SCB_LIST_NULL; + mov SAVED_SCSIID call set_busy_target; + if ((ahc->flags & AHC_SCB_BTT) != 0) { + mov SCBPTR, A; + } +setup_SCB_tagged: + clr SEQ_FLAGS; /* 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; + mvi HOST_MSG call mk_mesg; + jmp mesgin_done; + +not_found_cleanup_scb: + if ((ahc->flags & AHC_PAGESCBS) != 0) { + call cleanup_scb; + } +not_found: + mvi NO_MATCH call set_seqint; + jmp mesgin_done; + +mk_mesg: + if ((ahc->features & AHC_DT) == 0) { + or SCSISIGO, ATNO, LASTPHASE; + } else { + mvi SCSISIGO, 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_wait_perr: + mvi PERR_DETECTED call set_seqint; + jmp inb_next_wait; +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_perr; +inb_next_check_phase: + 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_TARGETROLE) != 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 wait at 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; +} + +/* + * Locate a disconnected SCB by SCBID. Upon return, SCBPTR and SINDEX will + * be set to the position of the SCB. If the SCB cannot be found locally, + * it will be paged in from host memory. RETURN_2 stores the address of the + * preceding SCB in the disconnected list which can be used to speed up + * removal of the found SCB from the disconnected list. + */ +if ((ahc->flags & AHC_PAGESCBS) != 0) { +BEGIN_CRITICAL; +findSCB: + mov A, SINDEX; /* Tag passed in SINDEX */ + cmp DISCONNECTED_SCBH, SCB_LIST_NULL je findSCB_notFound; + mov SCBPTR, DISCONNECTED_SCBH; /* Initialize SCBPTR */ + mvi ARG_2, SCB_LIST_NULL; /* Head of list */ + jmp findSCB_loop; +findSCB_next: + cmp SCB_NEXT, SCB_LIST_NULL je findSCB_notFound; + mov ARG_2, SCBPTR; + mov SCBPTR,SCB_NEXT; +findSCB_loop: + cmp SCB_TAG, A jne findSCB_next; +rem_scb_from_disc_list: + cmp ARG_2, SCB_LIST_NULL je rHead; + mov DINDEX, SCB_NEXT; + mov SINDEX, SCBPTR; + mov SCBPTR, ARG_2; + mov SCB_NEXT, DINDEX; + mov SCBPTR, SINDEX ret; +rHead: + mov DISCONNECTED_SCBH,SCB_NEXT ret; +END_CRITICAL; +findSCB_notFound: + /* + * We didn't find it. Page in the SCB. + */ + mov ARG_1, A; /* Save tag */ + mov ALLZEROS call get_free_or_disc_scb; + mvi DMAPARAMS, HDMAEN|DIRECTION|FIFORESET; + mov ARG_1 jmp dma_scb; +} + +/* + * Prepare the hardware to post a byte to host memory given an + * index of (A + (256 * SINDEX)) and a base address of SHARED_DATA_ADDR. + */ +post_byte_setup: + mov ARG_2, SINDEX; + if ((ahc->features & AHC_CMD_CHAN) != 0) { + mvi DINDEX, CCHADDR; + mvi SHARED_DATA_ADDR call set_1byte_addr; + mvi CCHCNT, 1; + mvi CCSCBCTL, CCSCBRESET ret; + } else { + mvi DINDEX, HADDR; + mvi SHARED_DATA_ADDR call set_1byte_addr; + mvi 1 call set_hcnt; + 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; + } + +phase_lock_perr: + mvi PERR_DETECTED call set_seqint; +phase_lock: + /* + * 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 phase_lock; + test SSTAT1, SCSIPERR jnz phase_lock_perr; +phase_lock_latch_phase: + if ((ahc->features & AHC_DT) == 0) { + and SCSISIGO, PHASE_MASK, SCSISIGI; + } + and LASTPHASE, PHASE_MASK, SCSISIGI ret; + +if ((ahc->features & AHC_CMD_CHAN) == 0) { +set_hcnt: + mov HCNT[0], SINDEX; +clear_hcnt: + clr HCNT[1]; + clr HCNT[2] ret; + +set_stcnt_from_hcnt: + mov STCNT[0], HCNT[0]; + mov STCNT[1], HCNT[1]; + mov STCNT[2], HCNT[2] ret; + +bcopy_8: + mov DINDIR, SINDIR; +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_TARGETROLE) != 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_2 * 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 an 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; + if ((ahc->flags & AHC_SCB_BTT) != 0) { + mvi CCHCNT, SCB_DOWNLOAD_SIZE_64; + } else { + mvi CCHCNT, SCB_DOWNLOAD_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_UPLOAD_SIZE; + if ((ahc->features & AHC_ULTRA2) == 0) { + mvi CCSCBCTL, CCSCBRESET; + bmov CCSCBRAM, SCB_BASE, SCB_UPLOAD_SIZE; + or CCSCBCTL, CCSCBEN|CCSCBRESET; + test CCSCBCTL, CCSCBDONE jz .; + } else if ((ahc->bugs & AHC_SCBCHAN_UPLOAD_BUG) != 0) { + mvi CCSCBCTL, CCARREN|CCSCBRESET; + cmp CCSCBCTL, ARRDONE|CCARREN jne .; + mvi CCHCNT, SCB_UPLOAD_SIZE; + mvi CCSCBCTL, CCSCBEN|CCSCBRESET; + cmp CCSCBCTL, CCSCBDONE|CCSCBEN jne .; + } 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 SCB_DOWNLOAD_SIZE call set_hcnt; + mov DFCNTRL, DMAPARAMS; + test DMAPARAMS, DIRECTION jnz dma_scb_fromhost; + /* Fill it with the SCB data */ +copy_scb_tofifo: + mvi SINDEX, SCB_BASE; + add A, SCB_DOWNLOAD_SIZE, SINDEX; +copy_scb_tofifo_loop: + call copy_to_fifo_8; + cmp SINDEX, A jne copy_scb_tofifo_loop; + or DFCNTRL, HDMAEN|FIFOFLUSH; + jmp dma_finish; +dma_scb_fromhost: + mvi DINDEX, SCB_BASE; + if ((ahc->bugs & AHC_PCI_2_1_RETRY_BUG) != 0) { + /* + * The PCI module will only issue a PCI + * retry if the data FIFO is empty. If the + * host disconnects in the middle of a + * transfer, we must empty the fifo of all + * available data to force the chip to + * continue the transfer. This does not + * happen for SCSI transfers as the SCSI module + * will drain the FIFO as data are made available. + * When the hang occurs, we know that a multiple + * of 8 bytes is in the FIFO because the PCI + * module has an 8 byte input latch that only + * dumps to the FIFO when HCNT == 0 or the + * latch is full. + */ + clr A; + /* Wait for at least 8 bytes of data to arrive. */ +dma_scb_hang_fifo: + test DFSTATUS, FIFOQWDEMP jnz dma_scb_hang_fifo; +dma_scb_hang_wait: + test DFSTATUS, MREQPEND jnz dma_scb_hang_wait; + test DFSTATUS, HDONE jnz dma_scb_hang_dma_done; + test DFSTATUS, HDONE jnz dma_scb_hang_dma_done; + test DFSTATUS, HDONE jnz dma_scb_hang_dma_done; + /* + * The PCI module no longer intends to perform + * a PCI transaction. Drain the fifo. + */ +dma_scb_hang_dma_drain_fifo: + not A, HCNT; + add A, SCB_DOWNLOAD_SIZE+SCB_BASE+1; + and A, ~0x7; + mov DINDIR,DFDAT; + cmp DINDEX, A jne . - 1; + cmp DINDEX, SCB_DOWNLOAD_SIZE+SCB_BASE + je dma_finish_nowait; + /* Restore A as the lines left to transfer. */ + add A, -SCB_BASE, DINDEX; + shr A, 3; + jmp dma_scb_hang_fifo; +dma_scb_hang_dma_done: + and DFCNTRL, ~HDMAEN; + test DFCNTRL, HDMAEN jnz .; + add SEQADDR0, A; + } else { + call dma_finish; + } + call dfdat_in_8; + call dfdat_in_8; + call dfdat_in_8; +dfdat_in_8: + mov DINDIR,DFDAT; +dfdat_in_7: + mov DINDIR,DFDAT; + mov DINDIR,DFDAT; + mov DINDIR,DFDAT; + mov DINDIR,DFDAT; + mov DINDIR,DFDAT; +dfdat_in_2: + mov DINDIR,DFDAT; + mov DINDIR,DFDAT ret; + } + +copy_to_fifo_8: + mov DFDAT,SINDIR; + mov DFDAT,SINDIR; +copy_to_fifo_6: + mov DFDAT,SINDIR; +copy_to_fifo_5: + mov DFDAT,SINDIR; +copy_to_fifo_4: + mov DFDAT,SINDIR; + mov DFDAT,SINDIR; + mov DFDAT,SINDIR; + mov DFDAT,SINDIR 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; +dma_finish_nowait: + /* Turn off DMA */ + and DFCNTRL, ~HDMAEN; + test DFCNTRL, HDMAEN jnz .; + ret; + +/* + * Restore an SCB that failed to match an incoming reselection + * to the correct/safe state. If the SCB is for a disconnected + * transaction, it must be returned to the disconnected list. + * If it is not in the disconnected state, it must be free. + */ +cleanup_scb: + if ((ahc->flags & AHC_PAGESCBS) != 0) { + test SCB_CONTROL,DISCONNECTED jnz add_scb_to_disc_list; + } +add_scb_to_free_list: + if ((ahc->flags & AHC_PAGESCBS) != 0) { +BEGIN_CRITICAL; + mov SCB_NEXT, FREE_SCBH; + mvi SCB_TAG, SCB_LIST_NULL; + mov FREE_SCBH, SCBPTR ret; +END_CRITICAL; + } else { + mvi SCB_TAG, SCB_LIST_NULL ret; + } + +if ((ahc->flags & AHC_39BIT_ADDRESSING) != 0) { +set_hhaddr: + or DSCOMMAND1, HADDLDSEL0; + and HADDR, SG_HIGH_ADDR_BITS, SINDEX; + and DSCOMMAND1, ~HADDLDSEL0 ret; +} + +if ((ahc->flags & AHC_PAGESCBS) != 0) { +get_free_or_disc_scb: +BEGIN_CRITICAL; + cmp FREE_SCBH, SCB_LIST_NULL jne dequeue_free_scb; + cmp DISCONNECTED_SCBH, SCB_LIST_NULL jne dequeue_disc_scb; +return_error: + mvi NO_FREE_SCB call set_seqint; + mvi SINDEX, SCB_LIST_NULL ret; +dequeue_disc_scb: + mov SCBPTR, DISCONNECTED_SCBH; + mov DISCONNECTED_SCBH, SCB_NEXT; +END_CRITICAL; + mvi DMAPARAMS, FIFORESET; + mov SCB_TAG jmp dma_scb; +BEGIN_CRITICAL; +dequeue_free_scb: + mov SCBPTR, FREE_SCBH; + mov FREE_SCBH, SCB_NEXT ret; +END_CRITICAL; + +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. + */ +BEGIN_CRITICAL; + mov SCB_NEXT, DISCONNECTED_SCBH; + mov DISCONNECTED_SCBH, SCBPTR ret; +END_CRITICAL; +} +set_seqint: + mov INTSTAT, SINDEX; + nop; +return: + ret; |