diff options
Diffstat (limited to 'sys/dev/tc/asc.c')
| -rw-r--r-- | sys/dev/tc/asc.c | 75 |
1 files changed, 68 insertions, 7 deletions
diff --git a/sys/dev/tc/asc.c b/sys/dev/tc/asc.c index 052ef1eedc4..c306a732d2d 100644 --- a/sys/dev/tc/asc.c +++ b/sys/dev/tc/asc.c @@ -1,4 +1,4 @@ -/* $NetBSD: asc.c,v 1.19.2.2 1996/06/04 21:21:44 mhitch Exp $ */ +/* $NetBSD: asc.c,v 1.19.2.3 1996/06/11 05:19:49 mhitch Exp $ */ /*- * Copyright (c) 1992, 1993 @@ -843,6 +843,13 @@ asc_startcmd(asc, target) } #endif + /* Try to avoid reselect collisions */ + if ((regs->asc_status & (ASC_CSR_INT|SCSI_PHASE_MSG_IN)) == + (ASC_CSR_INT|SCSI_PHASE_MSG_IN)) { +/* printf("asc_startcmd: possible reselect in progress\n"); */ + return; + } + /* * Init the chip and target state. */ @@ -912,11 +919,41 @@ asc_startcmd(asc, target) regs->asc_syn_o = state->sync_offset; readback(regs->asc_syn_o); + /* Try to avoid reselect collisions */ + if ((regs->asc_status & (ASC_CSR_INT|SCSI_PHASE_MSG_IN)) == + (ASC_CSR_INT|SCSI_PHASE_MSG_IN)) { +/* printf("asc_startcmd: reselect in progress (before select)\n");*/ + return; + } + if (state->flags & TRY_SYNC) - regs->asc_cmd = ASC_CMD_SEL_ATN_STOP; + regs->asc_cmd = len = ASC_CMD_SEL_ATN_STOP; else - regs->asc_cmd = ASC_CMD_SEL_ATN | ASC_CMD_DMA; + regs->asc_cmd = len = ASC_CMD_SEL_ATN | ASC_CMD_DMA; readback(regs->asc_cmd); + + /* Try to avoid reselect collisions */ + if ((regs->asc_status & (ASC_CSR_INT|SCSI_PHASE_MSG_IN)) == + (ASC_CSR_INT|SCSI_PHASE_MSG_IN)) { +/* printf("asc_startcmd: reselect in progress after select\n");*/ + return; + } else { + /* + * Here's a potentially nasty but infrequent problem: a + * reselect may have occurred, but did not interrupt. + */ + if (regs->asc_cmd != len && + regs->asc_cmd == (ASC_CMD_NOP|ASC_CMD_DMA)) { + if ((regs->asc_status & ASC_CSR_INT) == 0) { + delay(250); + if (regs->asc_status == SCSI_PHASE_MSG_IN) { + printf("asc_startcmd: reselect failed to interrupt?\n"); + /* XXXX THIS NEEDS FIXING */ + } + } + } + } + } /* @@ -966,6 +1003,12 @@ again: status, ss, ir, scpt - asc_scripts, scpt->condition); #endif + /* This must be done withing 250msec of disconnect */ + if (ir & ASC_INT_DISC) { + regs->asc_cmd = ASC_CMD_ENABLE_SEL; + readback(regs->asc_cmd); + } + /* check the expected state */ if (SCRIPT_MATCH(ir, status) == scpt->condition) { /* @@ -1007,6 +1050,21 @@ again: state = &asc->st[asc->target]; switch (ASC_PHASE(status)) { case SCSI_PHASE_DATAI: + if ((asc->script - asc_scripts) == SCRIPT_GET_STATUS) { + /* + * From the Mach driver: + * After a reconnect and restart dma in, we + * seem to have gotten an interrupt even though + * the DMA is running. The Mach driver just + * ignores this interrupt. + */ + ASC_TC_GET(regs, len); + fifo = regs->asc_flags & ASC_FLAGS_FIFO_CNT; + printf("asc_intr: ignoring strange interrupt"); + printf(" tc %d fifo residue\n", len, fifo); + goto done; + } + /* FALLTHROUGH */ case SCSI_PHASE_DATAO: ASC_TC_GET(regs, len); fifo = regs->asc_flags & ASC_FLAGS_FIFO_CNT; @@ -1184,10 +1242,6 @@ again: return 0 ; /* XXX ??? */ } - /* check for command errors */ - if (ir & ASC_INT_ILL) - goto abort; - /* check for disconnect */ if (ir & ASC_INT_DISC) { state = &asc->st[asc->target]; @@ -1246,6 +1300,13 @@ again: } } + /* mhitch - debug - check select/reselect collision */ + if ((ir & ASC_INT_ILL) && (regs->asc_cmd & ASC_CMD_SEL_ATN)) { + printf("asc_intr: Illegal command status %x ir %x\n", + status, ir); + /* Should process reselect? */ + } + /* check for reselect */ if (ir & ASC_INT_RESEL) { unsigned fifo, id, msg; |