freebsd-dev/sys/dev/aic7xxx/aic79xx.seq
Justin T. Gibbs 8fdc126111 Add a prefix to be used for assembler generated tables and
functions for register pretty-printing.

Implement "top bit of SCBID is valid bit" qoutfifo delivery scheme.

"the the" -> "the".

Remove old and never used tag collision chain handling in the
sequencer.  Tag collisions are never allowed to get as far as
on the controller.

Simplify busy target table handling routines.

Update comments to reflect reality.

Add support for catching more protocol violations.

Correct a bug in data fifo handling in mixed packetized and
non-packetized environments.  SG_STATE must be cleared even
if an SG fetch is not in progress at the time of FIFO shutdown
or we may confuse the non-packetized transaction idle-loop.
2002-08-31 06:49:55 +00:00

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/*
* Adaptec U320 device driver firmware for Linux and FreeBSD.
*
* Copyright (c) 1994-2001 Justin T. Gibbs.
* Copyright (c) 2000-2002 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/aic79xx.seq#51 $"
PATCH_ARG_LIST = "struct ahd_softc *ahd"
PREFIX = "ahd_"
#include "aic79xx.reg"
#include "scsi_message.h"
idle_loop:
SET_MODE(M_SCSI, M_SCSI);
test SCSISEQ0, ENSELO|ENARBO jnz idle_loop_checkbus;
test SEQ_FLAGS2, SELECTOUT_QFROZEN jnz idle_loop_checkbus;
cmp WAITING_TID_HEAD[1], SCB_LIST_NULL je idle_loop_checkbus;
/*
* ENSELO is cleared by a SELDO, so we must test for SELDO
* one last time.
*/
BEGIN_CRITICAL;
test SSTAT0, SELDO jnz select_out;
END_CRITICAL;
call start_selection;
idle_loop_checkbus:
BEGIN_CRITICAL;
test SSTAT0, SELDO jnz select_out;
END_CRITICAL;
test SSTAT0, SELDI jnz select_in;
test SCSIPHASE, ~DATA_PHASE_MASK jz idle_loop_check_nonpackreq;
test SCSISIGO, ATNO jz idle_loop_check_nonpackreq;
call unexpected_nonpkt_phase_find_ctxt;
idle_loop_check_nonpackreq:
test SSTAT2, NONPACKREQ jz idle_loop_scsi;
call unexpected_nonpkt_phase_find_ctxt;
idle_loop_scsi:
BEGIN_CRITICAL;
test LQISTAT2, LQIGSAVAIL jz idle_loop_service_fifos;
/*
* We have received good status for this transaction. There may
* still be data in our FIFOs draining to the host. Setup
* monitoring of the draining process or complete the SCB.
*/
good_status_IU_done:
bmov SCBPTR, GSFIFO, 2;
clr SCB_SCSI_STATUS;
or SCB_CONTROL, STATUS_RCVD;
/*
* Since this status did not consume a FIFO, we have to
* be a bit more dilligent in how we check for FIFOs pertaining
* to this transaction. There are three states that a FIFO still
* transferring data may be in.
*
* 1) Configured and draining to the host, with a pending CLRCHN.
* 2) Configured and draining to the host, no pending CLRCHN.
* 3) Pending cfg4data, fifo not empty.
*
* For case 1, we assume that our DMA post of the completed command
* will occur after the FIFO finishes draining due to the higher
* priority of data FIFO transfers relative to command channel
* transfers.
*
* Case 2 can be detected by noticing that a longjmp is active for the
* FIFO and LONGJMP_SCB matches our SCB. In this case, we allow
* the routine servicing the FIFO to complete the SCB.
*
* Case 3 implies either a pending or yet to occur save data
* pointers for this same context in the other FIFO. So, if
* we detect case 2, we will properly defer the post of the SCB
* and achieve the desired result. The pending cfg4data will
* notice that status has been received and complete the SCB.
*/
test SCB_SGPTR, SG_LIST_NULL jz good_status_check_fifos;
/*
* All segments have been loaded (or no data transfer), so
* it is safe to complete the command. Since this was a
* cheap command to check for completion, loop to see if
* more entries can be removed from the GSFIFO.
*/
call complete;
END_CRITICAL;
jmp idle_loop_scsi;
BEGIN_CRITICAL;
good_status_check_fifos:
clc;
bmov ARG_1, SCBPTR, 2;
SET_MODE(M_DFF0, M_DFF0);
call check_fifo;
jc idle_loop_service_fifos;
SET_MODE(M_DFF1, M_DFF1);
call check_fifo;
jc idle_loop_service_fifos;
SET_MODE(M_SCSI, M_SCSI);
call queue_scb_completion;
END_CRITICAL;
idle_loop_service_fifos:
SET_MODE(M_DFF0, M_DFF0);
test LONGJMP_ADDR[1], INVALID_ADDR jnz idle_loop_next_fifo;
call longjmp;
idle_loop_next_fifo:
SET_MODE(M_DFF1, M_DFF1);
test LONGJMP_ADDR[1], INVALID_ADDR jnz idle_loop_last_fifo_done;
call longjmp;
idle_loop_last_fifo_done:
call idle_loop_cchan;
jmp idle_loop;
idle_loop_cchan:
SET_MODE(M_CCHAN, M_CCHAN);
test CCSCBCTL, CCARREN|CCSCBEN jz scbdma_idle;
test CCSCBCTL, CCSCBDIR jnz fetch_new_scb_inprog;
test CCSCBCTL, CCSCBDONE jz return;
/* FALLTHROUGH */
scbdma_tohost_done:
test CCSCBCTL, CCARREN jz fill_qoutfifo_dmadone;
/*
* A complete SCB upload requires no intervention.
* The SCB is already on the COMPLETE_SCB list
* and its completion notification will now be
* handled just like any other SCB.
*/
and CCSCBCTL, ~(CCARREN|CCSCBEN) ret;
fill_qoutfifo_dmadone:
and CCSCBCTL, ~(CCARREN|CCSCBEN);
mvi INTSTAT, CMDCMPLT;
mvi COMPLETE_SCB_DMAINPROG_HEAD[1], SCB_LIST_NULL;
bmov QOUTFIFO_NEXT_ADDR, SCBHADDR, 4;
test QOFF_CTLSTA, SDSCB_ROLLOVR jz return;
bmov QOUTFIFO_NEXT_ADDR, SHARED_DATA_ADDR, 4;
xor QOUTFIFO_ENTRY_VALID_TAG, QOUTFIFO_ENTRY_VALID_TOGGLE ret;
fetch_new_scb_inprog:
test CCSCBCTL, ARRDONE jz return;
fetch_new_scb_done:
and CCSCBCTL, ~(CCARREN|CCSCBEN);
bmov REG0, SCBPTR, 2;
/* Update the next SCB address to download. */
bmov NEXT_QUEUED_SCB_ADDR, SCB_NEXT_SCB_BUSADDR, 4;
mvi SCB_NEXT[1], SCB_LIST_NULL;
mvi SCB_NEXT2[1], SCB_LIST_NULL;
/*
* SCBs that want to send messages are always
* queued independently. This ensures that they
* are at the head of the SCB list to select out
* to a target and we will see the MK_MESSAGE flag.
*/
test SCB_CONTROL, MK_MESSAGE jnz first_new_target_scb;
shr SINDEX, 3, SCB_SCSIID;
and SINDEX, ~0x1;
mvi SINDEX[1], (WAITING_SCB_TAILS >> 8);
bmov DINDEX, SINDEX, 2;
bmov SCBPTR, SINDIR, 2;
bmov DINDIR, REG0, 2;
cmp SCBPTR[1], SCB_LIST_NULL je first_new_target_scb;
bmov SCB_NEXT, REG0, 2;
fetch_new_scb_fini:
/* Increment our position in the QINFIFO. */
mov NONE, SNSCB_QOFF ret;
first_new_target_scb:
cmp WAITING_TID_HEAD[1], SCB_LIST_NULL je first_new_scb;
bmov SCBPTR, WAITING_TID_TAIL, 2;
bmov SCB_NEXT2, REG0, 2;
bmov WAITING_TID_TAIL, REG0, 2;
/* Increment our position in the QINFIFO. */
mov NONE, SNSCB_QOFF ret;
first_new_scb:
bmov WAITING_TID_HEAD, REG0, 2;
bmov WAITING_TID_TAIL, REG0, 2;
/* Increment our position in the QINFIFO. */
mov NONE, SNSCB_QOFF ret;
scbdma_idle:
/*
* Give precedence to downloading new SCBs to execute
* unless select-outs are currently frozen.
* XXX Use a timer to prevent completion starvation.
*/
test SEQ_FLAGS2, SELECTOUT_QFROZEN jnz . + 2;
BEGIN_CRITICAL;
test QOFF_CTLSTA, NEW_SCB_AVAIL jnz fetch_new_scb;
cmp COMPLETE_DMA_SCB_HEAD[1], SCB_LIST_NULL jne dma_complete_scb;
cmp COMPLETE_SCB_HEAD[1], SCB_LIST_NULL je return;
/* FALLTHROUGH */
fill_qoutfifo:
/*
* Keep track of the SCBs we are dmaing just
* in case the DMA fails or is aborted.
*/
mov A, QOUTFIFO_ENTRY_VALID_TAG;
bmov COMPLETE_SCB_DMAINPROG_HEAD, COMPLETE_SCB_HEAD, 2;
mvi CCSCBCTL, CCSCBRESET;
bmov SCBHADDR, QOUTFIFO_NEXT_ADDR, 4;
mov CCSCBRAM, COMPLETE_SCB_HEAD;
or CCSCBRAM, A, COMPLETE_SCB_HEAD[1];
bmov SCBPTR, COMPLETE_SCB_HEAD, 2;
jmp fill_qoutfifo_first_entry;
fill_qoutfifo_loop:
mov CCSCBRAM, SCB_NEXT_COMPLETE;
or CCSCBRAM, A, SCB_NEXT_COMPLETE[1];
bmov SCBPTR, SCB_NEXT_COMPLETE, 2;
fill_qoutfifo_first_entry:
mov NONE, SDSCB_QOFF;
cmp SCB_NEXT_COMPLETE[1], SCB_LIST_NULL je fill_qoutfifo_done;
cmp CCSCBADDR, CCSCBADDR_MAX je fill_qoutfifo_done;
test QOFF_CTLSTA, SDSCB_ROLLOVR jz fill_qoutfifo_loop;
fill_qoutfifo_done:
mov SCBHCNT, CCSCBADDR;
mvi CCSCBCTL, CCSCBEN|CCSCBRESET;
bmov COMPLETE_SCB_HEAD, SCB_NEXT_COMPLETE, 2;
mvi SCB_NEXT_COMPLETE[1], SCB_LIST_NULL ret;
fetch_new_scb:
bmov SCBHADDR, NEXT_QUEUED_SCB_ADDR, 4;
mvi CCARREN|CCSCBEN|CCSCBDIR|CCSCBRESET jmp dma_scb;
dma_complete_scb:
bmov SCBPTR, COMPLETE_DMA_SCB_HEAD, 2;
bmov SCBHADDR, SCB_BUSADDR, 4;
mvi CCARREN|CCSCBEN|CCSCBRESET call dma_scb;
/*
* Now that we've started the DMA, push us onto
* the normal completion queue to have our SCBID
* posted to the kernel.
*/
bmov COMPLETE_DMA_SCB_HEAD, SCB_NEXT_COMPLETE, 2;
bmov SCB_NEXT_COMPLETE, COMPLETE_SCB_HEAD, 2;
bmov COMPLETE_SCB_HEAD, SCBPTR, 2 ret;
END_CRITICAL;
/*
* Either post or fetch an SCB from host memory. The caller
* is responsible for polling for transfer completion.
*
* Prerequisits: Mode == M_CCHAN
* SINDEX contains CCSCBCTL flags
* SCBHADDR set to Host SCB address
* SCBPTR set to SCB src location on "push" operations
*/
SET_SRC_MODE M_CCHAN;
SET_DST_MODE M_CCHAN;
dma_scb:
mvi SCBHCNT, SCB_TRANSFER_SIZE;
mov CCSCBCTL, SINDEX;
or SEQ_FLAGS2, SCB_DMA ret;
BEGIN_CRITICAL;
setjmp_setscb:
bmov LONGJMP_SCB, SCBPTR, 2;
setjmp:
bmov LONGJMP_ADDR, STACK, 2 ret;
setjmp_inline:
bmov LONGJMP_ADDR, STACK, 2;
longjmp:
bmov STACK, LONGJMP_ADDR, 2 ret;
END_CRITICAL;
/************************ Packetized LongJmp Routines *************************/
/*
* Must disable interrupts when setting the mode pointer
* register as an interrupt occurring mid update will
* fail to store the new mode value for restoration on
* an iret.
*/
set_mode_work_around:
mvi SEQINTCTL, INTVEC1DSL;
mov MODE_PTR, SINDEX;
clr SEQINTCTL ret;
SET_SRC_MODE M_SCSI;
SET_DST_MODE M_SCSI;
start_selection:
BEGIN_CRITICAL;
if ((ahd->bugs & AHD_SENT_SCB_UPDATE_BUG) != 0) {
/*
* Razor #494
* Rev A hardware fails to update LAST/CURR/NEXTSCB
* correctly after a packetized selection in several
* situations:
*
* 1) If only one command existed in the queue, the
* LAST/CURR/NEXTSCB are unchanged.
*
* 2) In a non QAS, protocol allowed phase change,
* the queue is shifted 1 too far. LASTSCB is
* the last SCB that was correctly processed.
*
* 3) In the QAS case, if the full list of commands
* was successfully sent, NEXTSCB is NULL and neither
* CURRSCB nor LASTSCB can be trusted. We must
* manually walk the list counting MAXCMDCNT elements
* to find the last SCB that was sent correctly.
*
* To simplify the workaround for this bug in SELDO
* handling, we initialize LASTSCB prior to enabling
* selection so we can rely on it even for case #1 above.
*/
bmov LASTSCB, WAITING_TID_HEAD, 2;
}
bmov CURRSCB, WAITING_TID_HEAD, 2;
bmov SCBPTR, WAITING_TID_HEAD, 2;
shr SELOID, 4, SCB_SCSIID;
/*
* If we want to send a message to the device, ensure
* we are selecting with atn irregardless of our packetized
* agreement. Since SPI4 only allows target reset or PPR
* messages if this is a packetized connection, the change
* to our negotiation table entry for this selection will
* be cleared when the message is acted on.
*/
test SCB_CONTROL, MK_MESSAGE jz . + 3;
mov NEGOADDR, SELOID;
or NEGCONOPTS, ENAUTOATNO;
or SCSISEQ0, ENSELO ret;
END_CRITICAL;
/*
* Allocate a FIFO for a non-packetized transaction.
* For some reason unkown to me, both FIFOs must be free before we
* can allocate a FIFO for a non-packetized transaction. This
* may be fixed in Rev B.
*/
allocate_fifo_loop:
/*
* Do whatever work is required to free a FIFO.
*/
SET_MODE(M_DFF0, M_DFF0);
test LONGJMP_ADDR[1], INVALID_ADDR jnz . + 2;
call longjmp;
SET_MODE(M_DFF1, M_DFF1);
test LONGJMP_ADDR[1], INVALID_ADDR jnz . + 2;
call longjmp;
SET_MODE(M_SCSI, M_SCSI);
allocate_fifo:
and A, FIFO0FREE|FIFO1FREE, DFFSTAT;
cmp A, FIFO0FREE|FIFO1FREE jne allocate_fifo_loop;
take_fifo:
bmov ARG_1, SCBPTR, 2;
or DFFSTAT, CURRFIFO;
SET_MODE(M_DFF1, M_DFF1);
bmov SCBPTR, ARG_1, 2 ret;
/*
* We have been reselected as an initiator
* or selected as a target.
*/
SET_SRC_MODE M_SCSI;
SET_DST_MODE M_SCSI;
select_in:
or SXFRCTL0, SPIOEN;
and SAVED_SCSIID, SELID_MASK, SELID;
and A, OID, IOWNID;
or SAVED_SCSIID, A;
mvi CLRSINT0, CLRSELDI;
jmp ITloop;
/*
* We have successfully selected out.
*
* Clear SELDO.
* Dequeue all SCBs sent from the waiting queue
* Requeue all SCBs *not* sent to the tail of the waiting queue
* Take Razor #494 into account for above.
*
* In Packetized Mode:
* Return to the idle loop. Our interrupt handler will take
* care of any incoming L_Qs.
*
* In Non-Packetize Mode:
* Continue to our normal state machine.
*/
SET_SRC_MODE M_SCSI;
SET_DST_MODE M_SCSI;
select_out:
BEGIN_CRITICAL;
/* Clear out all SCBs that have been successfully sent. */
if ((ahd->bugs & AHD_SENT_SCB_UPDATE_BUG) != 0) {
/*
* For packetized, the LQO manager clears ENSELO on
* the assertion of SELDO. If we are non-packetized,
* LASTSCB and CURRSCB are acuate.
*/
test SCSISEQ0, ENSELO jnz use_lastscb;
/*
* The update is correct for LQOSTAT1 errors. All
* but LQOBUSFREE are handled by kernel interrupts.
* If we see LQOBUSFREE, return to the idle loop.
* Once we are out of the select_out critical section,
* the kernel will cleanup the LQOBUSFREE and we will
* eventually restart the selection if appropriate.
*/
test LQOSTAT1, LQOBUSFREE jnz idle_loop;
/*
* On a phase change oustside of packet boundaries,
* LASTSCB points to the currently active SCB context
* on the bus.
*/
test LQOSTAT2, LQOPHACHGOUTPKT jnz use_lastscb;
/*
* If the hardware has traversed the whole list, NEXTSCB
* will be NULL, CURRSCB and LASTSCB cannot be trusted,
* but MAXCMDCNT is accurate. If we stop part way through
* the list or only had one command to issue, NEXTSCB[1] is
* not NULL and LASTSCB is the last command to go out.
*/
cmp NEXTSCB[1], SCB_LIST_NULL jne use_lastscb;
/*
* Brute force walk.
*/
bmov SCBPTR, WAITING_TID_HEAD, 2;
mvi SEQINTCTL, INTVEC1DSL;
mvi MODE_PTR, MK_MODE(M_CFG, M_CFG);
mov A, MAXCMDCNT;
mvi MODE_PTR, MK_MODE(M_SCSI, M_SCSI);
clr SEQINTCTL;
find_lastscb_loop:
dec A;
test A, 0xFF jz found_last_sent_scb;
bmov SCBPTR, SCB_NEXT, 2;
jmp find_lastscb_loop;
use_lastscb:
bmov SCBPTR, LASTSCB, 2;
found_last_sent_scb:
bmov CURRSCB, SCBPTR, 2;
curscb_ww_done:
} else {
/*
* Untested - Verify with Rev B.
*/
bmov SCBPTR, CURRSCB, 2;
}
/*
* Requeue any SCBs not sent, to the tail of the waiting Q.
*/
cmp SCB_NEXT[1], SCB_LIST_NULL je select_out_list_done;
/*
* We know that neither the per-TID list nor the list of
* TIDs is empty. Use this knowledge to our advantage.
*/
bmov REG0, SCB_NEXT, 2;
bmov SCBPTR, WAITING_TID_TAIL, 2;
bmov SCB_NEXT2, REG0, 2;
bmov WAITING_TID_TAIL, REG0, 2;
jmp select_out_inc_tid_q;
select_out_list_done:
/*
* The whole list made it. Just clear our TID's tail pointer
* unless we were queued independently due to our need to
* send a message.
*/
test SCB_CONTROL, MK_MESSAGE jnz select_out_inc_tid_q;
shr DINDEX, 3, SCB_SCSIID;
/* XXX When we switch to SCB_SELOID, put +1 in addition below. */
or DINDEX, 1; /* Want only the second byte */
mvi DINDEX[1], ((WAITING_SCB_TAILS) >> 8);
mvi DINDIR, SCB_LIST_NULL;
select_out_inc_tid_q:
bmov SCBPTR, WAITING_TID_HEAD, 2;
bmov WAITING_TID_HEAD, SCB_NEXT2, 2;
cmp WAITING_TID_HEAD[1], SCB_LIST_NULL jne . + 2;
mvi WAITING_TID_TAIL[1], SCB_LIST_NULL;
bmov SCBPTR, CURRSCB, 2;
END_CRITICAL;
mvi CLRSINT0, CLRSELDO;
test LQOSTAT2, LQOPHACHGOUTPKT jnz unexpected_nonpkt_phase;
test LQOSTAT1, LQOPHACHGINPKT jnz unexpected_nonpkt_phase;
/*
* If this is a packetized connection, return to our
* idle_loop and let our interrupt handler deal with
* any connection setup/teardown issues. The only
* exception is the case of MK_MESSAGE SCBs. In the
* A, the LQO manager transitions to LQOSTOP0 even if
* we have selected out with ATN asserted and the target
* REQs in a non-packet phase.
*/
if ((ahd->bugs & AHD_LQO_ATNO_BUG) != 0) {
test SCB_CONTROL, MK_MESSAGE jz select_out_no_message;
test SCSISIGO, ATNO jnz select_out_non_packetized;
select_out_no_message:
}
test LQOSTAT2, LQOSTOP0 jnz idle_loop;
select_out_non_packetized:
/* Non packetized request. */
and SCSISEQ0, ~ENSELO;
mov SAVED_SCSIID, SCB_SCSIID;
mov SAVED_LUN, SCB_LUN;
or SXFRCTL0, SPIOEN;
/*
* 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;
/*
* 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_DT 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 SEQINTCODE, BAD_PHASE;
jmp ITloop; /* Try reading the bus again. */
/*
* Command phase. Set up the DMA registers and let 'er rip.
*/
p_command:
SET_SRC_MODE M_DFF1;
SET_DST_MODE M_DFF1;
test MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1))
jnz p_command_allocate_fifo;
/*
* Command retry. Free our current FIFO and
* re-allocate a FIFO so transfer state is
* reset.
*/
mvi DFFSXFRCTL, RSTCHN|CLRSHCNT;
p_command_allocate_fifo:
call allocate_fifo;
add NONE, -17, SCB_CDB_LEN;
jnc p_command_embedded;
p_command_from_host:
bmov HADDR[0], SCB_CDB_PTR, 11;
mvi SG_CACHE_PRE, LAST_SEG;
mvi DFCNTRL, (PRELOADEN|SCSIEN|HDMAEN);
jmp p_command_loop;
p_command_embedded:
bmov SHCNT[0], SCB_CDB_LEN, 1;
bmov SHCNT[1], ALLZEROS, 2;
bmov DFDAT, SCB_CDB_STORE, 16;
mvi DFCNTRL, SCSIEN;
p_command_loop:
test DFCNTRL, SCSIEN jnz p_command_loop;
/*
* DMA Channel automatically disabled.
* Don't allow a data phase if the command
* was not fully transferred. Make sure that
* we clear the IDENTIFY SEEN flag if a retry
* falls short too.
*/
and SEQ_FLAGS, ~NO_CDB_SENT;
test SSTAT2, SDONE jnz ITloop;
or SEQ_FLAGS, NO_CDB_SENT;
jmp ITloop;
/*
* Status phase. Wait for the data byte to appear, then read it
* and store it into the SCB.
*/
SET_SRC_MODE M_SCSI;
SET_DST_MODE M_SCSI;
p_status:
test SEQ_FLAGS,NOT_IDENTIFIED jz p_status_okay;
mvi SEQINTCODE, PROTO_VIOLATION;
jmp mesgin_done;
p_status_okay:
mov SCB_SCSI_STATUS, SCSIDAT;
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 */
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, SCB_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_NONPACKET_TAG as the tag value.
*/
p_mesgout_tag:
test SCB_CONTROL,TAG_ENB jz p_mesgout_onebyte;
mov SCSIDAT, SINDEX; /* Send the identify message */
call phase_lock;
cmp LASTPHASE, P_MESGOUT jne p_mesgout_done;
and SCSIDAT,TAG_ENB|SCB_TAG_TYPE,SCB_CONTROL;
call phase_lock;
cmp LASTPHASE, P_MESGOUT jne p_mesgout_done;
mov SCBPTR 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 SCSIDAT, 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:
/* read the 1st message byte */
mvi ACCUM call inb_first;
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:
call phase_lock; /* Benign the first time through. */
mvi SEQINTCODE, HOST_MSG_LOOP;
cmp RETURN_1, EXIT_MSG_LOOP je ITloop;
cmp RETURN_1, CONT_MSG_LOOP_WRITE jne . + 3;
mov SCSIDAT, RETURN_2;
jmp host_message_loop;
/* Must be CONT_MSG_LOOP_READ */
mov NONE, SCSIDAT; /* ACK Byte */
jmp host_message_loop;
mesgin_ign_wide_residue:
shr NEGOADDR, 4, SAVED_SCSIID;
test NEGCONOPTS, WIDEXFER jz mesgin_reject;
/* Pull the residue byte */
mvi REG0 call inb_next;
cmp REG0, 0x01 jne mesgin_reject;
test SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jz . + 2;
test DATA_COUNT_ODD, 0x1 jz mesgin_done;
mvi SEQINTCODE, IGN_WIDE_RES;
jmp mesgin_done;
mesgin_reject:
mvi MSG_MESSAGE_REJECT call mk_mesg;
mesgin_done:
mov NONE,SCSIDAT; /*dummy read from latch to ACK*/
jmp ITloop;
#define INDEX_DISC_LIST_SCB(scsiid, lun) \
and A, 0xC0, scsiid; \
or SCBPTR, A, lun; \
clr SCBPTR[1]
#define INDEX_DISC_LIST(scsiid, lun) \
INDEX_DISC_LIST_SCB(scsiid, lun); \
and SINDEX, 0x30, scsiid; \
shr SINDEX, 3; /* Multiply by 2 */ \
add SINDEX, (SCB_DISCONNECTED_LISTS & 0xFF); \
mvi SINDEX[1], ((SCB_DISCONNECTED_LISTS >> 8) & 0xFF)
mesgin_identify:
/*
* Determine whether a target is using tagged or non-tagged
* transactions by first looking at the transaction stored in
* the per-device, disconnected array. If there is no untagged
* transaction for this target, this must be a tagged transaction.
*/
and SAVED_LUN, MSG_IDENTIFY_LUNMASK, A;
INDEX_DISC_LIST(SAVED_SCSIID, SAVED_LUN);
bmov DINDEX, SINDEX, 2;
bmov REG0, SINDIR, 2;
cmp REG0[1], SCB_LIST_NULL je snoop_tag;
/* Untagged. Clear the busy table entry and setup the SCB. */
bmov DINDIR, ALLONES, 2;
bmov SCBPTR, REG0, 2;
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. After receiving the tag, look for the SCB at SCB locations tag and
* tag + 256.
*/
snoop_tag:
if ((ahd->flags & AHD_SEQUENCER_DEBUG) != 0) {
or SEQ_FLAGS, 0x80;
}
mov NONE, SCSIDAT; /* ACK Identify MSG */
call phase_lock;
if ((ahd->flags & AHD_SEQUENCER_DEBUG) != 0) {
or SEQ_FLAGS, 0x1;
}
cmp LASTPHASE, P_MESGIN jne not_found_ITloop;
if ((ahd->flags & AHD_SEQUENCER_DEBUG) != 0) {
or SEQ_FLAGS, 0x2;
}
cmp SCSIBUS, MSG_SIMPLE_Q_TAG jne not_found;
get_tag:
clr SCBPTR[1];
mvi SCBPTR call inb_next; /* tag value */
verify_scb:
test SCB_CONTROL,DISCONNECTED jz verify_other_scb;
mov A, SAVED_SCSIID;
cmp SCB_SCSIID, A jne verify_other_scb;
mov A, SAVED_LUN;
cmp SCB_LUN, A je setup_SCB_disconnected;
verify_other_scb:
xor SCBPTR[1], 1;
test SCBPTR[1], 0xFF jnz verify_scb;
jmp not_found;
/*
* Ensure that the SCB the tag points to is for
* an SCB transaction to the reconnecting target.
*/
setup_SCB:
if ((ahd->flags & AHD_SEQUENCER_DEBUG) != 0) {
or SEQ_FLAGS, 0x10;
}
test SCB_CONTROL,DISCONNECTED jz not_found;
setup_SCB_disconnected:
and SCB_CONTROL,~DISCONNECTED;
clr SEQ_FLAGS; /* make note of IDENTIFY */
test SCB_SGPTR, SG_LIST_NULL jnz . + 2;
call allocate_fifo;
/* 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:
mvi SEQINTCODE, NO_MATCH;
jmp mesgin_done;
not_found_ITloop:
mvi SEQINTCODE, NO_MATCH;
jmp ITloop;
/*
* We received a "command complete" message. Put the SCB on the complete
* queue and trigger a completion interrupt via the idle loop. 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_proto_violation:
mvi SEQINTCODE, PROTO_VIOLATION;
jmp mesgin_done;
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 SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT jnz . + 2;
test SCB_CONTROL, STATUS_RCVD jnz 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_complete_proto_violation;
/*
* If the target never gave us status information, have
* the host abort the command.
*/
test SCB_CONTROL, STATUS_RCVD jz mesgin_complete_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_complete_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 SEQINTCODE, MKMSG_FAILED;
call queue_scb_completion;
jmp await_busfree;
freeze_queue:
/* Cancel any pending select-out. */
test SSTAT0, SELDO jnz . + 2;
and SCSISEQ0, ~ENSELO;
mov ACCUM_SAVE, A;
clr A;
add QFREEZE_COUNT, 1;
adc QFREEZE_COUNT[1], A;
or SEQ_FLAGS2, SELECTOUT_QFROZEN;
mov A, ACCUM_SAVE ret;
queue_arg1_scb_completion:
SET_MODE(M_SCSI, M_SCSI);
bmov SCBPTR, ARG_1, 2;
queue_scb_completion:
test SCB_SCSI_STATUS,0xff jnz bad_status;
/*
* Check for residuals
*/
test SCB_SGPTR, SG_LIST_NULL jnz complete; /* No xfer */
test SCB_SGPTR, SG_FULL_RESID jnz upload_scb;/* Never xfered */
test SCB_RESIDUAL_SGPTR, SG_LIST_NULL jz upload_scb;
complete:
bmov SCB_NEXT_COMPLETE, COMPLETE_SCB_HEAD, 2;
bmov COMPLETE_SCB_HEAD, SCBPTR, 2 ret;
bad_status:
cmp SCB_SCSI_STATUS, STATUS_PKT_SENSE je upload_scb;
call freeze_queue;
upload_scb:
bmov SCB_NEXT_COMPLETE, COMPLETE_DMA_SCB_HEAD, 2;
bmov COMPLETE_DMA_SCB_HEAD, SCBPTR, 2;
or SCB_SGPTR, SG_STATUS_VALID ret;
/*
* 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 jz disconnect_allowed;
mvi SEQINTCODE, PROTO_VIOLATION;
jmp mesgin_done;
disconnect_allowed:
or SCB_CONTROL,DISCONNECTED;
test SCB_CONTROL, TAG_ENB jnz await_busfree;
queue_disc_scb:
bmov REG0, SCBPTR, 2;
INDEX_DISC_LIST(SAVED_SCSIID, SAVED_LUN);
bmov DINDEX, SINDEX, 2;
bmov DINDIR, REG0, 2;
bmov SCBPTR, REG0, 2;
/* FALLTHROUGH */
await_busfree:
and SIMODE1, ~ENBUSFREE;
mov NONE, SCSIDAT; /* Ack the last byte */
call clear_target_state;
test MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1))
jnz await_busfree_not_m_dff;
SET_SRC_MODE M_DFF1;
SET_DST_MODE M_DFF1;
await_busfree_clrchn:
mvi DFFSXFRCTL, CLRCHN;
await_busfree_not_m_dff:
test SSTAT1,REQINIT|BUSFREE jz .;
test SSTAT1, BUSFREE jnz idle_loop;
mvi SEQINTCODE, MISSED_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.
*/
SET_SRC_MODE M_DFF1;
SET_DST_MODE M_DFF1;
mesgin_sdptrs:
mov NONE,SCSIDAT; /*dummy read from latch to ACK*/
test SEQ_FLAGS, DPHASE jz ITloop;
call save_pointers;
jmp ITloop;
save_pointers:
/*
* 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 save_pointers_full;
or SCB_SGPTR, SG_LIST_NULL ret;
save_pointers_full:
/*
* The SCB_DATAPTR becomes the current SHADDR.
* All other information comes directly from our residual
* state.
*/
bmov SCB_DATAPTR, SHADDR, 8;
bmov SCB_DATACNT, SCB_RESIDUAL_DATACNT, 8 ret;
/*
* 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 phase.
*/
mesgin_rdptrs:
and SEQ_FLAGS, ~DPHASE;
test MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1)) jnz msgin_rdptrs_get_fifo;
mvi DFFSXFRCTL, RSTCHN|CLRSHCNT;
msgin_rdptrs_get_fifo:
call allocate_fifo;
jmp mesgin_done;
clear_target_state:
mvi LASTPHASE, P_BUSFREE;
/* clear target specific flags */
mvi SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT ret;
phase_lock:
test SCSIPHASE, 0xFF jz .;
phase_lock_latch_phase:
and LASTPHASE, PHASE_MASK, SCSISIGI ret;
/*
* Functions to read data in Automatic PIO mode.
*
* 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,SCSIDAT; /*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 SCSIPHASE, 0xFF jz .;
inb_next_check_phase:
and LASTPHASE, PHASE_MASK, SCSISIGI;
cmp LASTPHASE, P_MESGIN jne mesgin_phasemis;
inb_first:
clr DINDEX[1];
mov DINDEX,SINDEX;
mov DINDIR,SCSIBUS ret; /*read byte directly from bus*/
inb_last:
mov NONE,SCSIDAT ret; /*dummy read from latch to ACK*/
mk_mesg:
mvi SCSISIGO, ATNO;
mov MSG_OUT,SINDEX ret;
SET_SRC_MODE M_DFF1;
SET_DST_MODE M_DFF1;
disable_ccsgen:
test SG_STATE, FETCH_INPROG jz disable_ccsgen_fetch_done;
clr CCSGCTL;
disable_ccsgen_fetch_done:
clr SG_STATE ret;
toggle_dff_mode:
mvi SEQINTCTL, INTVEC1DSL;
xor MODE_PTR, MK_MODE(M_DFF1, M_DFF1);
clr SEQINTCTL ret;
data_group_idle_loop:
mov SAVED_MODE, MODE_PTR;
test SG_STATE, LOADING_NEEDED jz . + 2;
call service_fifo;
call toggle_dff_mode;
test SG_STATE, LOADING_NEEDED jz . + 2;
call service_fifo;
call idle_loop_cchan;
mov SAVED_MODE jmp set_mode_work_around;
service_fifo:
/*
* Do we have any prefetch left???
*/
test SG_STATE, SEGS_AVAIL jnz idle_sg_avail;
/*
* Can this FIFO have access to the S/G cache yet?
*/
test CCSGCTL, SG_CACHE_AVAIL jz return;
/* Did we just finish fetching segs? */
cmp CCSGCTL, CCSGEN|SG_CACHE_AVAIL|CCSGDONE
je idle_sgfetch_complete;
/* Are we actively fetching segments? */
test CCSGCTL, CCSGEN 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 SGHCNT, SG_PREFETCH_CNT;
and SGHADDR[0], SG_PREFETCH_ALIGN_MASK, SCB_RESIDUAL_SGPTR;
bmov SGHADDR[1], SCB_RESIDUAL_SGPTR[1], 3;
mvi CCSGCTL, CCSGEN|SG_CACHE_AVAIL|CCSGRESET;
or SG_STATE, FETCH_INPROG ret;
idle_sgfetch_complete:
/*
* Guard against SG_CACHE_AVAIL activating during sg fetch
* request in the other FIFO.
*/
test SG_STATE, FETCH_INPROG jz return;
clr CCSGCTL;
and CCSGADDR, SG_PREFETCH_ADDR_MASK, SCB_RESIDUAL_SGPTR;
mvi SG_STATE, SEGS_AVAIL|LOADING_NEEDED;
idle_sg_avail:
/* Does the hardware have space for another SG entry? */
test DFSTATUS, PRELOAD_AVAIL jz return;
if ((ahd->flags & AHD_64BIT_ADDRESSING) != 0) {
bmov HADDR, CCSGRAM, 8;
} else {
bmov HADDR, CCSGRAM, 4;
}
bmov HCNT, CCSGRAM, 3;
test HCNT[0], 0x1 jz . + 2;
xor DATA_COUNT_ODD, 0x1;
bmov SCB_RESIDUAL_DATACNT[3], CCSGRAM, 1;
if ((ahd->flags & AHD_39BIT_ADDRESSING) != 0) {
and HADDR[4], SG_HIGH_ADDR_BITS, SCB_RESIDUAL_DATACNT[3];
}
if ((ahd->flags & AHD_64BIT_ADDRESSING) != 0) {
/* Skip 4 bytes of pad. */
add CCSGADDR, 4;
}
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;
mov SINDEX, SCB_RESIDUAL_SGPTR[0];
test DATA_COUNT_ODD, 0x1 jz . + 2;
or SINDEX, ODD_SEG;
test SCB_RESIDUAL_DATACNT[3], SG_LAST_SEG jz . + 3;
or SINDEX, LAST_SEG;
clr SG_STATE;
mov SG_CACHE_PRE, SINDEX;
/*
* Load the segment. Or in HDMAEN here too
* just in case HDMAENACK has not come true
* by the time this segment is loaded. If
* HDMAENACK is not true, this or will disable
* HDMAEN mid-transfer. We do not want to simply
* mvi our original settings as SCSIEN automatically
* de-asserts and we don't want to accidentally
* re-enable it.
*/
or DFCNTRL, PRELOADEN|HDMAEN;
/*
* Do we have another segment in the cache?
*/
add NONE, SG_PREFETCH_CNT_LIMIT, CCSGADDR;
jnc return;
and SG_STATE, ~SEGS_AVAIL ret;
/*
* Initialize the DMA address and counter from the SCB.
*/
load_first_seg:
bmov HADDR, SCB_DATAPTR, 11;
and DATA_COUNT_ODD, 0x1, SCB_DATACNT[0];
and REG0, ~SG_FULL_RESID, SCB_SGPTR[0];
test SCB_DATACNT[3], SG_LAST_SEG jz . + 2;
or REG0, LAST_SEG;
test DATA_COUNT_ODD, 0x1 jz . + 2;
or REG0, ODD_SEG;
mov SG_CACHE_PRE, REG0;
mvi DFCNTRL, (PRELOADEN|SCSIEN|HDMAEN);
/*
* Since we've are entering a data phase, we will
* rely on the SCB_RESID* fields. Initialize the
* residual and clear the full residual flag.
*/
and SCB_SGPTR[0], ~SG_FULL_RESID;
bmov SCB_RESIDUAL_DATACNT[3], SCB_DATACNT[3], 5;
/* If we need more S/G elements, tell the idle loop */
test SCB_RESIDUAL_DATACNT[3], SG_LAST_SEG jnz . + 2;
mvi SG_STATE, LOADING_NEEDED ret;
clr SG_STATE ret;
p_data:
test SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT jz p_data_allowed;
mvi SEQINTCODE, PROTO_VIOLATION;
p_data_allowed:
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
* unless we already know that we should be bitbucketing.
*/
test SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jnz p_data_bitbucket;
mvi SEQINTCODE, PDATA_REINIT;
p_data_bitbucket:
/*
* Turn on `Bit Bucket' mode, wait until the target takes
* us to another phase, and then notify the host.
*/
test MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1))
jnz bitbucket_not_m_dff;
/*
* Ensure that any FIFO contents are cleared out and the
* FIFO free'd prior to starting the BITBUCKET. BITBUCKET
* doesn't discard data already in the FIFO.
*/
mvi DFFSXFRCTL, RSTCHN|CLRSHCNT;
SET_MODE(M_SCSI, M_SCSI);
bitbucket_not_m_dff:
or SXFRCTL1,BITBUCKET;
test SCSIPHASE, DATA_PHASE_MASK jnz .;
and SXFRCTL1, ~BITBUCKET;
SET_MODE(M_DFF1, M_DFF1);
mvi SEQINTCODE, DATA_OVERRUN;
jmp ITloop;
data_phase_initialize:
test SCB_SGPTR[0], SG_LIST_NULL jnz p_data_bitbucket;
call load_first_seg;
data_phase_inbounds:
/* We have seen a data phase at least once. */
or SEQ_FLAGS, DPHASE;
data_group_dma_loop:
/*
* The transfer is complete if either the last segment
* completes or the target changes phase. Both conditions
* will clear SCSIEN.
*/
call data_group_idle_loop;
test DFCNTRL, SCSIEN jnz data_group_dma_loop;
data_group_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.
*/
call calc_residual;
/*
* Go ahead and shut down the DMA engine now.
*/
test DFCNTRL, DIRECTION jnz data_phase_finish;
data_group_fifoflush:
if ((ahd->bugs & AHD_AUTOFLUSH_BUG) != 0) {
or DFCNTRL, FIFOFLUSH;
}
/*
* We have enabled the auto-ack feature. 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. We know there is more data yet to transfer
* if SG_LIST_NULL is not yet set, thus there cannot be
* an overrun.
*/
test SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL jz data_phase_finish;
test SG_CACHE_SHADOW, LAST_SEG_DONE jz .;
test DFSTATUS, FIFOEMP jnz data_phase_finish;
/* Overrun */
jmp p_data;
data_phase_finish:
/*
* If the target has left us in data phase, loop through
* the dma code again. We will only loop if there is a
* data overrun.
*/
if ((ahd->flags & AHD_TARGETROLE) != 0) {
test SSTAT0, TARGET jnz data_phase_done;
}
if ((ahd->flags & AHD_INITIATORROLE) != 0) {
test SSTAT1, REQINIT jz .;
test SCSIPHASE, DATA_PHASE_MASK jnz p_data;
}
data_phase_done:
/* Kill off any pending prefetch */
call disable_ccsgen;
if ((ahd->flags & AHD_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 DATA_COUNT_ODD, 0x1 jz target_ITloop;
SET_MODE(M_SCSI, M_SCSI);
test NEGCONOPTS, 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;
}
/*
* 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.
*/
calc_residual:
test SG_CACHE_SHADOW, LAST_SEG jz residual_before_last_seg;
/* Record if we've consumed all S/G entries */
test MDFFSTAT, SHVALID jz . + 2;
bmov SCB_RESIDUAL_DATACNT, SHCNT, 3 ret;
or SCB_RESIDUAL_SGPTR[0], SG_LIST_NULL ret;
residual_before_last_seg:
test MDFFSTAT, SHVALID jnz sgptr_fixup;
/*
* Can never happen from an interrupt as the packetized
* hardware will only interrupt us once SHVALID or
* LAST_SEG_DONE.
*/
call data_group_idle_loop;
jmp calc_residual;
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_CACHE_PTR 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;
clr DATA_COUNT_ODD;
test SG_CACHE_SHADOW, ODD_SEG jz . + 2;
or DATA_COUNT_ODD, 0x1;
clr SCB_RESIDUAL_DATACNT[3]; /* We are not the last seg */
bmov SCB_RESIDUAL_DATACNT, SHCNT, 3 ret;
export seq_isr:
nop; /* Jumps in the first ISR instruction fail on Rev A. */
test SEQINTSRC, SAVEPTRS jnz saveptr_intr;
test SEQINTSRC, CFG4DATA jnz cfg4data_intr;
test SEQINTSRC, CFG4ISTAT jnz cfg4istat_intr;
test SEQINTSRC, CFG4ICMD jnz cfg4icmd_intr;
mvi SEQINTCODE, INVALID_SEQINT;
/*
* There are two types of save pointers interrupts:
* The first is a snapshot save pointers where the current FIFO is not
* active and contains a snapshot of the current poniter information.
* This happens between packets in a stream for a single L_Q. Since we
* are not performing a pointer save, we can safely clear the channel
* so it can be used for other transactions.
*
* The second case is a save pointers on an active FIFO which occurs
* if the target changes to a new L_Q or busfrees/QAS' and the transfer
* has a residual. This should occur coincident with a ctxtdone. We
* disable the interrupt and allow our active routine to handle the
* save.
*/
saveptr_intr:
test DFCNTRL, HDMAENACK jz snapshot_saveptr;
and SEQIMODE, ~ENSAVEPTRS;
or SEQINTCTL, IRET ret;
snapshot_saveptr:
mvi DFFSXFRCTL, CLRCHN;
or SEQINTCTL, IRET ret;
cfg4data_intr:
test SCB_SGPTR[0], SG_LIST_NULL jnz pkt_handle_overrun;
call load_first_seg;
call pkt_handle_xfer;
or SEQINTCTL, IRET ret;
cfg4istat_intr:
call freeze_queue;
add NONE, -13, SCB_CDB_LEN;
jnc cfg4istat_have_sense_addr;
test SCB_CDB_LEN, SCB_CDB_LEN_PTR jnz cfg4istat_have_sense_addr;
/*
* Host sets up address/count and enables transfer.
*/
mvi SEQINTCODE, CFG4ISTAT_INTR;
jmp cfg4istat_setup_handler;
cfg4istat_have_sense_addr:
bmov HADDR, SCB_SENSE_BUSADDR, 4;
mvi HCNT[1], (AHD_SENSE_BUFSIZE >> 8);
mvi SG_CACHE_PRE, LAST_SEG;
mvi DFCNTRL, PRELOADEN|SCSIEN|HDMAEN;
cfg4istat_setup_handler:
/*
* Status pkt is transferring to host.
* Wait in idle loop for transfer to complete.
*/
call pkt_handle_status;
or SEQINTCTL, IRET ret;
/*
* See if the target has gone on in this context creating an
* overrun condition. For the write case, the hardware cannot
* ack bytes until data is provided. So, if the target begins
* another packet without changing contexts, implying we are
* not sitting on a packet boundary, we are in an overrun
* situation. For the read case, the hardware will continue to
* ack bytes into the FIFO, and may even ack the last overrun packet
* into the FIFO. If the FIFO should become non-empty, we are in
* a read overrun case.
*/
#define check_overrun \
/* Not on a packet boundary. */ \
test MDFFSTAT, DLZERO jz pkt_handle_overrun; \
test DFSTATUS, FIFOEMP jz pkt_handle_overrun
pkt_handle_xfer:
bmov LONGJMP_SCB, SCBPTR, 2;
test SG_STATE, LOADING_NEEDED jz pkt_last_seg;
call setjmp;
test SEQINTSRC, SAVEPTRS jnz pkt_saveptrs;
test SCSIPHASE, ~DATA_PHASE_MASK jz . + 2;
test SCSISIGO, ATNO jnz . + 2;
test SSTAT2, NONPACKREQ jz pkt_service_fifo;
/*
* Defer handling of this NONPACKREQ until we
* can be sure it pertains to this FIFO. SAVEPTRS
* will not be asserted if the NONPACKREQ is for us,
* so we must simulate it if shaddow is valid. If
* shaddow is not valid, keep running this FIFO until we
* have satisfied the transfer by loading segments and
* waiting for either shaddow valid or last_seg_done.
*/
test MDFFSTAT, SHVALID jnz pkt_saveptrs;
pkt_service_fifo:
test SG_STATE, LOADING_NEEDED jnz service_fifo;
pkt_last_seg:
call setjmp;
test SEQINTSRC, SAVEPTRS jnz pkt_saveptrs;
test SG_CACHE_SHADOW, LAST_SEG_DONE jnz last_pkt_done;
test SCSIPHASE, ~DATA_PHASE_MASK jz . + 2;
test SCSISIGO, ATNO jnz . + 2;
test SSTAT2, NONPACKREQ jz return;
test MDFFSTAT, SHVALID jnz pkt_saveptrs;
jmp return;
last_pkt_done:
BEGIN_CRITICAL;
if ((ahd->bugs & AHD_AUTOFLUSH_BUG) != 0) {
or DFCNTRL, FIFOFLUSH;
}
test SCB_CONTROL, STATUS_RCVD jz wait_pkt_end;
check_overrun;
or SCB_SGPTR, SG_LIST_NULL;
/*
* I think it is safe to skip the FIFO check.
* in this case as LAST_SEG_DONE implies
* the other FIFO, if ever active for this transfer,
* has completed.
*/
last_pkt_queue_scb:
or LONGJMP_ADDR[1], INVALID_ADDR;
bmov ARG_1, SCBPTR, 2;
mvi DFFSXFRCTL, CLRCHN;
jmp queue_arg1_scb_completion;
last_pkt_complete:
bmov ARG_1, SCBPTR, 2;
mvi DFFSXFRCTL, CLRCHN;
check_other_fifo:
clc;
call toggle_dff_mode;
call check_fifo;
jnc queue_arg1_scb_completion;
return:
ret;
wait_pkt_end:
call setjmp;
END_CRITICAL;
wait_pkt_end_loop:
test SEQINTSRC, CTXTDONE jnz pkt_end;
check_overrun;
test SSTAT2, NONPACKREQ jz return;
test SEQINTSRC, CTXTDONE jz unexpected_nonpkt_phase;
pkt_end:
BEGIN_CRITICAL;
check_overrun;
or LONGJMP_ADDR[1], INVALID_ADDR;
or SCB_SGPTR, SG_LIST_NULL;
test SCB_CONTROL, STATUS_RCVD jnz last_pkt_complete;
mvi DFFSXFRCTL, CLRCHN ret;
END_CRITICAL;
/*
* Either a SAVEPTRS interrupt condition is pending for this FIFO
* or we have a pending nonpackreq for this FIFO. We differentiate
* between the two by capturing the state of the SAVEPTRS interrupt
* prior to clearing and handling the common code of these two cases.
*/
pkt_saveptrs:
BEGIN_CRITICAL;
if ((ahd->bugs & AHD_AUTOFLUSH_BUG) != 0) {
or DFCNTRL, FIFOFLUSH;
}
mov REG0, SEQINTSRC;
mvi CLRSEQINTSRC, CLRSAVEPTRS;
call calc_residual;
call save_pointers;
call disable_ccsgen;
or SEQIMODE, ENSAVEPTRS;
or LONGJMP_ADDR[1], INVALID_ADDR;
pkt_saveptrs_check_status:
test REG0, SAVEPTRS jz unexpected_nonpkt_phase;
test SCB_CONTROL, STATUS_RCVD jz pkt_saveptrs_clrchn;
jmp last_pkt_complete;
pkt_saveptrs_clrchn:
mvi DFFSXFRCTL, CLRCHN ret;
END_CRITICAL;
check_status_overrun:
test SHCNT[2], 0xFF jz status_IU_done;
mvi SEQINTCODE, STATUS_OVERRUN;
jmp status_IU_done;
pkt_handle_status:
call setjmp_setscb;
test MDFFSTAT, LASTSDONE jnz check_status_overrun;
test SEQINTSRC, CTXTDONE jz return;
status_IU_done:
BEGIN_CRITICAL;
if ((ahd->bugs & AHD_AUTOFLUSH_BUG) != 0) {
or DFCNTRL, FIFOFLUSH;
}
or LONGJMP_ADDR[1], INVALID_ADDR;
mvi SCB_SCSI_STATUS, STATUS_PKT_SENSE;
or SCB_CONTROL, STATUS_RCVD;
jmp last_pkt_complete;
END_CRITICAL;
SET_SRC_MODE M_DFF0;
SET_DST_MODE M_DFF0;
BEGIN_CRITICAL;
check_fifo:
test LONGJMP_ADDR[1], INVALID_ADDR jnz return;
mov A, ARG_2;
cmp LONGJMP_SCB[1], A jne return;
mov A, ARG_1;
cmp LONGJMP_SCB[0], A jne return;
stc ret;
END_CRITICAL;
/*
* Nonpackreq is a polled status. It can come true in three situations:
* we have received an L_Q, we have sent one or more L_Qs, or there is no
* L_Q context associated with this REQ (REQ occurs immediately after a
* (re)selection). Routines that know that the context responsible for this
* nonpackreq call directly into unexpected_nonpkt_phase. In the case of the
* top level idle loop, we exhaust all active contexts prior to determining that
* we simply do not have the full I_T_L_Q for this phase.
*/
unexpected_nonpkt_phase_find_ctxt:
/*
* This nonpackreq is most likely associated with one of the tags
* in a FIFO or an outgoing LQ. Only treat it as an I_T only
* nonpackreq if we've cleared out the FIFOs and handled any
* pending SELDO.
*/
SET_SRC_MODE M_SCSI;
SET_DST_MODE M_SCSI;
and A, FIFO1FREE|FIFO0FREE, DFFSTAT;
cmp A, FIFO1FREE|FIFO0FREE jne return;
test SSTAT0, SELDO jnz return;
mvi SCBPTR[1], SCB_LIST_NULL;
unexpected_nonpkt_phase:
test MODE_PTR, ~(MK_MODE(M_DFF1, M_DFF1)) jnz . + 3;
SET_SRC_MODE M_DFF0;
SET_DST_MODE M_DFF0;
or LONGJMP_ADDR[1], INVALID_ADDR;
mvi DFFSXFRCTL, CLRCHN;
mvi CLRSINT2, CLRNONPACKREQ;
test SCSIPHASE, ~(MSG_IN_PHASE|MSG_OUT_PHASE) jnz illegal_phase;
mvi SEQINTCODE, ENTERING_NONPACK;
jmp ITloop;
illegal_phase:
mvi SEQINTCODE, ILLEGAL_PHASE;
jmp ITloop;
/*
* We have entered an overrun situation. If we have working
* BITBUCKET, flip that on and let the hardware eat any overrun
* data. Otherwise use an overrun buffer in the host to simulate
* BITBUCKET.
*/
pkt_handle_overrun:
mvi SEQINTCODE, CFG4OVERRUN;
call freeze_queue;
if ((ahd->bugs & AHD_PKT_BITBUCKET_BUG) == 0) {
SET_MODE(M_SCSI, M_SCSI);
or SXFRCTL1,BITBUCKET;
SET_SRC_MODE M_DFF1;
SET_DST_MODE M_DFF1;
} else {
call load_overrun_buf;
mvi DFCNTRL, (HDMAEN|SCSIEN|PRELOADEN);
}
call setjmp;
if ((ahd->bugs & AHD_PKT_BITBUCKET_BUG) != 0) {
test DFSTATUS, PKT_PRELOAD_AVAIL jz overrun_load_done;
call load_overrun_buf;
or DFCNTRL, PRELOADEN;
overrun_load_done:
}
test SEQINTSRC, CTXTDONE jnz pkt_overrun_end;
test SSTAT2, NONPACKREQ jz return;
pkt_overrun_end:
or SCB_RESIDUAL_SGPTR, SG_OVERRUN_RESID;
test SEQINTSRC, CTXTDONE jz unexpected_nonpkt_phase;
test SCB_CONTROL, STATUS_RCVD jnz last_pkt_queue_scb;
mvi DFFSXFRCTL, CLRCHN ret;
if ((ahd->bugs & AHD_PKT_BITBUCKET_BUG) != 0) {
load_overrun_buf:
/*
* Load a dummy segment if preload space is available.
*/
mov HADDR[0], SHARED_DATA_ADDR;
add HADDR[1], PKT_OVERRUN_BUFOFFSET, SHARED_DATA_ADDR[1];
mov ACCUM_SAVE, A;
clr A;
adc HADDR[2], A, SHARED_DATA_ADDR[2];
adc HADDR[3], A, SHARED_DATA_ADDR[3];
mov A, ACCUM_SAVE;
bmov HADDR[4], ALLZEROS, 4;
/* PKT_OVERRUN_BUFSIZE is a multiple of 256 */
clr HCNT[0];
mvi HCNT[1], ((PKT_OVERRUN_BUFSIZE >> 8) & 0xFF);
clr HCNT[2];
}
cfg4icmd_intr: