diff options
Diffstat (limited to 'drivers/scsi/aic7xxx/aic79xx.seq')
| -rw-r--r-- | drivers/scsi/aic7xxx/aic79xx.seq | 143 |
1 files changed, 120 insertions, 23 deletions
diff --git a/drivers/scsi/aic7xxx/aic79xx.seq b/drivers/scsi/aic7xxx/aic79xx.seq index bef1f9d369b..58bc17591b5 100644 --- a/drivers/scsi/aic7xxx/aic79xx.seq +++ b/drivers/scsi/aic7xxx/aic79xx.seq @@ -1,7 +1,7 @@ /* * Adaptec U320 device driver firmware for Linux and FreeBSD. * - * Copyright (c) 1994-2001 Justin T. Gibbs. + * Copyright (c) 1994-2001, 2004 Justin T. Gibbs. * Copyright (c) 2000-2002 Adaptec Inc. * All rights reserved. * @@ -40,7 +40,7 @@ * $FreeBSD$ */ -VERSION = "$Id: //depot/aic7xxx/aic7xxx/aic79xx.seq#119 $" +VERSION = "$Id: //depot/aic7xxx/aic7xxx/aic79xx.seq#120 $" PATCH_ARG_LIST = "struct ahd_softc *ahd" PREFIX = "ahd_" @@ -110,10 +110,8 @@ check_waiting_list: * one last time. */ 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; @@ -294,7 +292,6 @@ fetch_new_scb_inprog: test CCSCBCTL, ARRDONE jz return; fetch_new_scb_done: and CCSCBCTL, ~(CCARREN|CCSCBEN); - bmov REG0, SCBPTR, 2; clr A; add CMDS_PENDING, 1; adc CMDS_PENDING[1], A; @@ -316,43 +313,117 @@ fetch_new_scb_done: clr SCB_FIFO_USE_COUNT; /* Update the next SCB address to download. */ bmov NEXT_QUEUED_SCB_ADDR, SCB_NEXT_SCB_BUSADDR, 4; + /* + * NULL out the SCB links since these fields + * occupy the same location as SCB_NEXT_SCB_BUSADDR. + */ mvi SCB_NEXT[1], SCB_LIST_NULL; mvi SCB_NEXT2[1], SCB_LIST_NULL; /* Increment our position in the QINFIFO. */ mov NONE, SNSCB_QOFF; + /* - * 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. + * Save SCBID of this SCB in REG0 since + * SCBPTR will be clobbered during target + * list updates. We also record the SCB's + * flags so that we can refer to them even + * after SCBPTR has been changed. + */ + bmov REG0, SCBPTR, 2; + mov A, SCB_CONTROL; + + /* + * Find the tail SCB of the execution queue + * for this target. */ - 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; + + /* + * Update the tail to point to the new SCB. + */ bmov DINDIR, REG0, 2; + + /* + * If the queue was empty, queue this SCB as + * the first for this target. + */ cmp SCBPTR[1], SCB_LIST_NULL je first_new_target_scb; + + /* + * SCBs that want to send messages must always be + * at the head of their per-target queue so that + * ATN can be asserted even if the current + * negotiation agreement is packetized. If the + * target queue is empty, the SCB can be queued + * immediately. If the queue is not empty, we must + * wait for it to empty before entering this SCB + * into the waiting for selection queue. Otherwise + * our batching and round-robin selection scheme + * could allow commands to be queued out of order. + * To simplify the implementation, we stop pulling + * new commands from the host until the MK_MESSAGE + * SCB can be queued to the waiting for selection + * list. + */ + test A, MK_MESSAGE jz batch_scb; + + /* + * If the last SCB is also a MK_MESSAGE SCB, then + * order is preserved even if we batch. + */ + test SCB_CONTROL, MK_MESSAGE jz batch_scb; + + /* + * Defer this SCB and stop fetching new SCBs until + * it can be queued. Since the SCB_SCSIID of the + * tail SCB must be the same as that of the newly + * queued SCB, there is no need to restore the SCBID + * here. + */ + or SEQ_FLAGS2, PENDING_MK_MESSAGE; + bmov MK_MESSAGE_SCB, REG0, 2; + mov MK_MESSAGE_SCSIID, SCB_SCSIID ret; + +batch_scb: + /* + * Otherwise just update the previous tail SCB to + * point to the new tail. + */ bmov SCB_NEXT, REG0, 2 ret; + first_new_target_scb: + /* + * Append SCB to the tail of the waiting for + * selection list. + */ 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 ret; first_new_scb: + /* + * Whole list is empty, so the head of + * the list must be initialized too. + */ bmov WAITING_TID_HEAD, REG0, 2; bmov WAITING_TID_TAIL, REG0, 2 ret; END_CRITICAL; scbdma_idle: /* - * Give precedence to downloading new SCBs to execute - * unless select-outs are currently frozen. + * Don't bother downloading new SCBs to execute + * if select-outs are currently frozen or we have + * a MK_MESSAGE SCB waiting to enter the queue. */ - test SEQ_FLAGS2, SELECTOUT_QFROZEN jnz . + 2; + test SEQ_FLAGS2, SELECTOUT_QFROZEN|PENDING_MK_MESSAGE + jnz scbdma_no_new_scbs; BEGIN_CRITICAL; test QOFF_CTLSTA, NEW_SCB_AVAIL jnz fetch_new_scb; +scbdma_no_new_scbs: cmp COMPLETE_DMA_SCB_HEAD[1], SCB_LIST_NULL jne dma_complete_scb; cmp COMPLETE_SCB_HEAD[1], SCB_LIST_NULL je return; /* FALLTHROUGH */ @@ -671,27 +742,41 @@ curscb_ww_done: } /* - * Requeue any SCBs not sent, to the tail of the waiting Q. + * The whole list made it. Clear our tail pointer to indicate + * that the per-target selection queue is now empty. */ - cmp SCB_NEXT[1], SCB_LIST_NULL je select_out_list_done; + cmp SCB_NEXT[1], SCB_LIST_NULL je select_out_clear_tail; /* + * Requeue any SCBs not sent, to the tail of the waiting Q. * We know that neither the per-TID list nor the list of - * TIDs is empty. Use this knowledge to our advantage. + * TIDs is empty. Use this knowledge to our advantage and + * queue the remainder to the tail of the global execution + * queue. */ bmov REG0, SCB_NEXT, 2; +select_out_queue_remainder: 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: +select_out_clear_tail: + /* + * Queue any pending MK_MESSAGE SCB for this target now + * that the queue is empty. + */ + test SEQ_FLAGS2, PENDING_MK_MESSAGE jz select_out_no_mk_message_scb; + mov A, MK_MESSAGE_SCSIID; + cmp SCB_SCSIID, A jne select_out_no_mk_message_scb; + and SEQ_FLAGS2, ~PENDING_MK_MESSAGE; + bmov REG0, MK_MESSAGE_SCB, 2; + jmp select_out_queue_remainder; + +select_out_no_mk_message_scb: /* - * 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. + * Clear this target's execution tail and increment the queue. */ - test SCB_CONTROL, MK_MESSAGE jnz select_out_inc_tid_q; shr DINDEX, 3, SCB_SCSIID; or DINDEX, 1; /* Want only the second byte */ mvi DINDEX[1], ((WAITING_SCB_TAILS) >> 8); @@ -703,8 +788,8 @@ select_out_inc_tid_q: mvi WAITING_TID_TAIL[1], SCB_LIST_NULL; bmov SCBPTR, CURRSCB, 2; mvi CLRSINT0, CLRSELDO; - test LQOSTAT2, LQOPHACHGOUTPKT jnz unexpected_nonpkt_phase; - test LQOSTAT1, LQOPHACHGINPKT jnz unexpected_nonpkt_phase; + test LQOSTAT2, LQOPHACHGOUTPKT jnz unexpected_nonpkt_mode_cleared; + test LQOSTAT1, LQOPHACHGINPKT jnz unexpected_nonpkt_mode_cleared; /* * If this is a packetized connection, return to our @@ -2127,6 +2212,18 @@ SET_DST_MODE M_DFF0; mvi DFFSXFRCTL, CLRCHN; unexpected_nonpkt_mode_cleared: mvi CLRSINT2, CLRNONPACKREQ; + if ((ahd->bugs & AHD_BUSFREEREV_BUG) != 0) { + /* + * Test to ensure that the bus has not + * already gone free prior to clearing + * any stale busfree status. This avoids + * a window whereby a busfree just after + * a selection could be missed. + */ + test SCSISIGI, BSYI jz . + 2; + mvi CLRSINT1,CLRBUSFREE; + or SIMODE1, ENBUSFREE; + } test SCSIPHASE, ~(MSG_IN_PHASE|MSG_OUT_PHASE) jnz illegal_phase; SET_SEQINTCODE(ENTERING_NONPACK) jmp ITloop; |