X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fscsi%2Faic7xxx%2Faic79xx.seq;fp=drivers%2Fscsi%2Faic7xxx%2Faic79xx.seq;h=58bc17591b54ce56082d67aa937f9a8f7e51a0fe;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=65339bc1ca99cd3f9b960703aa2b5e3c1520d452;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git diff --git a/drivers/scsi/aic7xxx/aic79xx.seq b/drivers/scsi/aic7xxx/aic79xx.seq index 65339bc1c..58bc17591 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#99 $" +VERSION = "$Id: //depot/aic7xxx/aic7xxx/aic79xx.seq#120 $" PATCH_ARG_LIST = "struct ahd_softc *ahd" PREFIX = "ahd_" @@ -68,18 +68,50 @@ no_error_set: } SET_MODE(M_SCSI, M_SCSI) test SCSISEQ0, ENSELO|ENARBO jnz idle_loop_checkbus; - test SEQ_FLAGS2, SELECTOUT_QFROZEN jnz idle_loop_checkbus; + test SEQ_FLAGS2, SELECTOUT_QFROZEN jz check_waiting_list; + /* + * If the kernel has caught up with us, thaw the queue. + */ + mov A, KERNEL_QFREEZE_COUNT; + cmp QFREEZE_COUNT, A jne check_frozen_completions; + mov A, KERNEL_QFREEZE_COUNT[1]; + cmp QFREEZE_COUNT[1], A jne check_frozen_completions; + and SEQ_FLAGS2, ~SELECTOUT_QFROZEN; + jmp check_waiting_list; +check_frozen_completions: + test SSTAT0, SELDO|SELINGO jnz idle_loop_checkbus; +BEGIN_CRITICAL; + /* + * If we have completions stalled waiting for the qfreeze + * to take effect, move them over to the complete_scb list + * now that no selections are pending. + */ + cmp COMPLETE_ON_QFREEZE_HEAD[1],SCB_LIST_NULL je idle_loop_checkbus; + /* + * Find the end of the qfreeze list. The first element has + * to be treated specially. + */ + bmov SCBPTR, COMPLETE_ON_QFREEZE_HEAD, 2; + cmp SCB_NEXT_COMPLETE[1], SCB_LIST_NULL je join_lists; + /* + * Now the normal loop. + */ + bmov SCBPTR, SCB_NEXT_COMPLETE, 2; + cmp SCB_NEXT_COMPLETE[1], SCB_LIST_NULL jne . - 1; +join_lists: + bmov SCB_NEXT_COMPLETE, COMPLETE_SCB_HEAD, 2; + bmov COMPLETE_SCB_HEAD, COMPLETE_ON_QFREEZE_HEAD, 2; + mvi COMPLETE_ON_QFREEZE_HEAD[1], SCB_LIST_NULL; + jmp idle_loop_checkbus; +check_waiting_list: 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; @@ -90,6 +122,13 @@ idle_loop_check_nonpackreq: test SSTAT2, NONPACKREQ jz . + 2; call unexpected_nonpkt_phase_find_ctxt; if ((ahd->bugs & AHD_FAINT_LED_BUG) != 0) { + /* + * On Rev A. hardware, the busy LED is only + * turned on automaically during selections + * and re-selections. Make the LED status + * more useful by forcing it to be on so + * long as one of our data FIFOs is active. + */ and A, FIFO0FREE|FIFO1FREE, DFFSTAT; cmp A, FIFO0FREE|FIFO1FREE jne . + 3; and SBLKCTL, ~DIAGLEDEN|DIAGLEDON; @@ -101,9 +140,9 @@ idle_loop_check_nonpackreq: call idle_loop_cchan; jmp idle_loop; -BEGIN_CRITICAL; idle_loop_gsfifo: SET_MODE(M_SCSI, M_SCSI) +BEGIN_CRITICAL; idle_loop_gsfifo_in_scsi_mode: test LQISTAT2, LQIGSAVAIL jz return; /* @@ -152,11 +191,15 @@ END_CRITICAL; idle_loop_service_fifos: SET_MODE(M_DFF0, M_DFF0) +BEGIN_CRITICAL; test LONGJMP_ADDR[1], INVALID_ADDR jnz idle_loop_next_fifo; call longjmp; +END_CRITICAL; idle_loop_next_fifo: SET_MODE(M_DFF1, M_DFF1) +BEGIN_CRITICAL; test LONGJMP_ADDR[1], INVALID_ADDR jz longjmp; +END_CRITICAL; return: ret; @@ -170,7 +213,6 @@ BEGIN_CRITICAL; test CCSCBCTL, CCARREN|CCSCBEN jz scbdma_idle; test CCSCBCTL, CCSCBDIR jnz fetch_new_scb_inprog; test CCSCBCTL, CCSCBDONE jz return; -END_CRITICAL; /* FALLTHROUGH */ scbdma_tohost_done: test CCSCBCTL, CCARREN jz fill_qoutfifo_dmadone; @@ -180,26 +222,18 @@ scbdma_tohost_done: * bad SCSI status (currently only for underruns), we * queue the SCB for normal completion. Otherwise, we * wait until any select-out activity has halted, and - * then notify the host so that the transaction can be - * dealt with. + * then queue the completion. */ - test SCB_SCSI_STATUS, 0xff jnz scbdma_notify_host; and CCSCBCTL, ~(CCARREN|CCSCBEN); bmov COMPLETE_DMA_SCB_HEAD, SCB_NEXT_COMPLETE, 2; + cmp SCB_NEXT_COMPLETE[1], SCB_LIST_NULL jne . + 2; + mvi COMPLETE_DMA_SCB_TAIL[1], SCB_LIST_NULL; + test SCB_SCSI_STATUS, 0xff jz scbdma_queue_completion; + bmov SCB_NEXT_COMPLETE, COMPLETE_ON_QFREEZE_HEAD, 2; + bmov COMPLETE_ON_QFREEZE_HEAD, SCBPTR, 2 ret; +scbdma_queue_completion: bmov SCB_NEXT_COMPLETE, COMPLETE_SCB_HEAD, 2; bmov COMPLETE_SCB_HEAD, SCBPTR, 2 ret; -scbdma_notify_host: - SET_MODE(M_SCSI, M_SCSI) - test SCSISEQ0, ENSELO jnz return; - test SSTAT0, (SELDO|SELINGO) jnz return; - SET_MODE(M_CCHAN, M_CCHAN) - /* - * Remove SCB and notify host. - */ - and CCSCBCTL, ~(CCARREN|CCSCBEN); - bmov COMPLETE_DMA_SCB_HEAD, SCB_NEXT_COMPLETE, 2; - SET_SEQINTCODE(BAD_SCB_STATUS) - ret; fill_qoutfifo_dmadone: and CCSCBCTL, ~(CCARREN|CCSCBEN); call qoutfifo_updated; @@ -208,6 +242,7 @@ fill_qoutfifo_dmadone: 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; +END_CRITICAL; qoutfifo_updated: /* @@ -257,7 +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; @@ -279,43 +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 */ @@ -324,14 +432,15 @@ 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 A, QOUTFIFO_NEXT_ADDR; bmov SCBPTR, COMPLETE_SCB_HEAD, 2; fill_qoutfifo_loop: - mov CCSCBRAM, SCBPTR; - or CCSCBRAM, A, SCBPTR[1]; + bmov CCSCBRAM, SCBPTR, 2; + mov CCSCBRAM, SCB_SGPTR[0]; + mov CCSCBRAM, QOUTFIFO_ENTRY_VALID_TAG; mov NONE, SDSCB_QOFF; inc INT_COALESCING_CMDCOUNT; add CMDS_PENDING, -1; @@ -339,6 +448,18 @@ fill_qoutfifo_loop: 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 jnz fill_qoutfifo_done; + /* + * Don't cross an ADB or Cachline boundary when DMA'ing + * completion entries. In PCI mode, at least in 32/33 + * configurations, the SCB DMA engine may lose its place + * in the data-stream should the target force a retry on + * something other than an 8byte aligned boundary. In + * PCI-X mode, we do this to avoid split transactions since + * many chipsets seem to be unable to format proper split + * completions to continue the data transfer. + */ + add SINDEX, A, CCSCBADDR; + test SINDEX, CACHELINE_MASK jz fill_qoutfifo_done; bmov SCBPTR, SCB_NEXT_COMPLETE, 2; jmp fill_qoutfifo_loop; fill_qoutfifo_done: @@ -354,7 +475,6 @@ dma_complete_scb: bmov SCBPTR, COMPLETE_DMA_SCB_HEAD, 2; bmov SCBHADDR, SCB_BUSADDR, 4; mvi CCARREN|CCSCBEN|CCSCBRESET jmp dma_scb; -END_CRITICAL; /* * Either post or fetch an SCB from host memory. The caller @@ -371,9 +491,19 @@ dma_scb: mvi SCBHCNT, SCB_TRANSFER_SIZE; mov CCSCBCTL, SINDEX ret; -BEGIN_CRITICAL; setjmp: - bmov LONGJMP_ADDR, STACK, 2 ret; + /* + * At least on the A, a return in the same + * instruction as the bmov results in a return + * to the caller, not to the new address at the + * top of the stack. Since we want the latter + * (we use setjmp to register a handler from an + * interrupt context but not invoke that handler + * until we return to our idle loop), use a + * separate ret instruction. + */ + bmov LONGJMP_ADDR, STACK, 2; + ret; setjmp_inline: bmov LONGJMP_ADDR, STACK, 2; longjmp: @@ -392,11 +522,6 @@ set_mode_work_around: mvi SEQINTCTL, INTVEC1DSL; mov MODE_PTR, SINDEX; clr SEQINTCTL ret; - -toggle_dff_mode_work_around: - mvi SEQINTCTL, INTVEC1DSL; - xor MODE_PTR, MK_MODE(M_DFF1, M_DFF1); - clr SEQINTCTL ret; } @@ -490,6 +615,21 @@ allocate_fifo1: SET_SRC_MODE M_SCSI; SET_DST_MODE M_SCSI; select_in: + if ((ahd->bugs & AHD_FAINT_LED_BUG) != 0) { + /* + * On Rev A. hardware, the busy LED is only + * turned on automaically during selections + * and re-selections. Make the LED status + * more useful by forcing it to be on from + * the point of selection until our idle + * loop determines that neither of our FIFOs + * are busy. This handles the non-packetized + * case nicely as we will not return to the + * idle loop until the busfree at the end of + * each transaction. + */ + or SBLKCTL, DIAGLEDEN|DIAGLEDON; + } if ((ahd->bugs & AHD_BUSFREEREV_BUG) != 0) { /* * Test to ensure that the bus has not @@ -528,6 +668,21 @@ SET_SRC_MODE M_SCSI; SET_DST_MODE M_SCSI; select_out: BEGIN_CRITICAL; + if ((ahd->bugs & AHD_FAINT_LED_BUG) != 0) { + /* + * On Rev A. hardware, the busy LED is only + * turned on automaically during selections + * and re-selections. Make the LED status + * more useful by forcing it to be on from + * the point of re-selection until our idle + * loop determines that neither of our FIFOs + * are busy. This handles the non-packetized + * case nicely as we will not return to the + * idle loop until the busfree at the end of + * each transaction. + */ + or SBLKCTL, DIAGLEDEN|DIAGLEDON; + } /* Clear out all SCBs that have been successfully sent. */ if ((ahd->bugs & AHD_SENT_SCB_UPDATE_BUG) != 0) { /* @@ -587,27 +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: /* - * 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. + * 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: + /* + * 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); @@ -619,8 +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 @@ -1000,15 +1169,9 @@ not_found_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. + * 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. */ mesgin_complete: @@ -1053,6 +1216,7 @@ complete_nomsg: call queue_scb_completion; jmp await_busfree; +BEGIN_CRITICAL; freeze_queue: /* Cancel any pending select-out. */ test SSTAT0, SELDO|SELINGO jnz . + 2; @@ -1063,6 +1227,7 @@ freeze_queue: adc QFREEZE_COUNT[1], A; or SEQ_FLAGS2, SELECTOUT_QFROZEN; mov A, ACCUM_SAVE ret; +END_CRITICAL; /* * Complete the current FIFO's SCB if data for this same @@ -1085,8 +1250,10 @@ queue_scb_completion: test SCB_SGPTR, SG_FULL_RESID jnz upload_scb;/* Never xfered */ test SCB_RESIDUAL_SGPTR, SG_LIST_NULL jz upload_scb; complete: +BEGIN_CRITICAL; bmov SCB_NEXT_COMPLETE, COMPLETE_SCB_HEAD, 2; bmov COMPLETE_SCB_HEAD, SCBPTR, 2 ret; +END_CRITICAL; bad_status: cmp SCB_SCSI_STATUS, STATUS_PKT_SENSE je upload_scb; call freeze_queue; @@ -1097,9 +1264,18 @@ upload_scb: * it on the host. */ bmov SCB_TAG, SCBPTR, 2; - bmov SCB_NEXT_COMPLETE, COMPLETE_DMA_SCB_HEAD, 2; +BEGIN_CRITICAL; + or SCB_SGPTR, SG_STATUS_VALID; + mvi SCB_NEXT_COMPLETE[1], SCB_LIST_NULL; + cmp COMPLETE_DMA_SCB_HEAD[1], SCB_LIST_NULL jne add_dma_scb_tail; bmov COMPLETE_DMA_SCB_HEAD, SCBPTR, 2; - or SCB_SGPTR, SG_STATUS_VALID ret; + bmov COMPLETE_DMA_SCB_TAIL, SCBPTR, 2 ret; +add_dma_scb_tail: + bmov REG0, SCBPTR, 2; + bmov SCBPTR, COMPLETE_DMA_SCB_TAIL, 2; + bmov SCB_NEXT_COMPLETE, REG0, 2; + bmov COMPLETE_DMA_SCB_TAIL, REG0, 2 ret; +END_CRITICAL; /* * Is it a disconnect message? Set a flag in the SCB to remind us @@ -1146,8 +1322,18 @@ SET_DST_MODE M_DFF1; await_busfree_clrchn: mvi DFFSXFRCTL, CLRCHN; await_busfree_not_m_dff: - call clear_target_state; + /* clear target specific flags */ + mvi SEQ_FLAGS, NOT_IDENTIFIED|NO_CDB_SENT; test SSTAT1,REQINIT|BUSFREE jz .; + /* + * We only set BUSFREE status once either a new + * phase has been detected or we are really + * BUSFREE. This allows the driver to know + * that we are active on the bus even though + * no identified transaction exists should a + * timeout occur while awaiting busfree. + */ + mvi LASTPHASE, P_BUSFREE; test SSTAT1, BUSFREE jnz idle_loop; SET_SEQINTCODE(MISSED_BUSFREE) @@ -1202,11 +1388,6 @@ 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: if ((ahd->bugs & AHD_EARLY_REQ_BUG) != 0) { /* @@ -1297,6 +1478,47 @@ service_fifo: /* Are we actively fetching segments? */ test CCSGCTL, CCSGENACK jnz return; + /* + * Should the other FIFO get the S/G cache first? If + * both FIFOs have been allocated since we last checked + * any FIFO, it is important that we service a FIFO + * that is not actively on the bus first. This guarantees + * that a FIFO will be freed to handle snapshot requests for + * any FIFO that is still on the bus. Chips with RTI do not + * perform snapshots, so don't bother with this test there. + */ + if ((ahd->features & AHD_RTI) == 0) { + /* + * If we're not still receiving SCSI data, + * it is safe to allocate the S/G cache to + * this FIFO. + */ + test DFCNTRL, SCSIEN jz idle_sgfetch_start; + + /* + * Switch to the other FIFO. Non-RTI chips + * also have the "set mode" bug, so we must + * disable interrupts during the switch. + */ + mvi SEQINTCTL, INTVEC1DSL; + xor MODE_PTR, MK_MODE(M_DFF1, M_DFF1); + + /* + * If the other FIFO needs loading, then it + * must not have claimed the S/G cache yet + * (SG_CACHE_AVAIL would have been cleared in + * the orginal FIFO mode and we test this above). + * Return to the idle loop so we can process the + * FIFO not currently on the bus first. + */ + test SG_STATE, LOADING_NEEDED jz idle_sgfetch_okay; + clr SEQINTCTL ret; +idle_sgfetch_okay: + xor MODE_PTR, MK_MODE(M_DFF1, M_DFF1); + clr SEQINTCTL; + } + +idle_sgfetch_start: /* * We fetch a "cacheline aligned" and sized amount of data * so we don't end up referencing a non-existant page. @@ -1308,7 +1530,7 @@ service_fifo: mvi SGHCNT, SG_PREFETCH_CNT; if ((ahd->bugs & AHD_REG_SLOW_SETTLE_BUG) != 0) { /* - * Need two instruction between "touches" of SGHADDR. + * Need two instructions between "touches" of SGHADDR. */ nop; } @@ -1658,7 +1880,7 @@ export seq_isr: * savepointer in the current FIFO. We do this so that * a pending CTXTDONE or SAVEPTR is visible in the active * FIFO. This status is the only way we can detect if we - * have lost the race (e.g. host paused us) and our attepts + * have lost the race (e.g. host paused us) and our attempts * to disable the channel occurred after all REQs were * already seen and acked (REQINIT never comes true). */ @@ -1667,7 +1889,7 @@ export seq_isr: test DFCNTRL, DIRECTION jz interrupt_return; and DFCNTRL, ~SCSIEN; snapshot_wait_data_valid: - test SEQINTSRC, (CTXTDONE|SAVEPTRS) jnz snapshot_data_valid; + test SEQINTSRC, (CTXTDONE|SAVEPTRS) jnz interrupt_return; test SSTAT1, REQINIT jz snapshot_wait_data_valid; snapshot_data_valid: or DFCNTRL, SCSIEN; @@ -1834,7 +2056,6 @@ pkt_saveptrs_check_status: dec SCB_FIFO_USE_COUNT; test SCB_CONTROL, STATUS_RCVD jnz pkt_complete_scb_if_fifos_idle; mvi DFFSXFRCTL, CLRCHN ret; -END_CRITICAL; /* * LAST_SEG_DONE status has been seen in the current FIFO. @@ -1843,7 +2064,6 @@ END_CRITICAL; * Check for overrun and see if we can complete this command. */ pkt_last_seg_done: -BEGIN_CRITICAL; /* * Mark transfer as completed. */ @@ -1992,6 +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;