diff options
Diffstat (limited to 'drivers/scsi/NCR5380.c')
| -rw-r--r-- | drivers/scsi/NCR5380.c | 218 |
1 files changed, 10 insertions, 208 deletions
diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c index 98840bed05cb..826b63d1aa84 100644 --- a/drivers/scsi/NCR5380.c +++ b/drivers/scsi/NCR5380.c @@ -35,18 +35,10 @@ * code so that everything does the same thing that's done at the * end of a pseudo-DMA read operation. * - * 2. Fix REAL_DMA (interrupt driven, polled works fine) - - * basically, transfer size needs to be reduced by one - * and the last byte read as is done with PSEUDO_DMA. - * * 4. Test SCSI-II tagged queueing (I have no devices which support * tagged queueing) */ -#ifndef notyet -#undef REAL_DMA -#endif - #ifdef BOARD_REQUIRES_NO_DELAY #define io_recovery_delay(x) #else @@ -131,12 +123,6 @@ * * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases. * - * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. - * - * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't - * rely on phase mismatch and EOP interrupts to determine end - * of phase. - * * These macros MUST be defined : * * NCR5380_read(register) - read from the specified register @@ -147,15 +133,9 @@ * specific implementation of the NCR5380 * * Either real DMA *or* pseudo DMA may be implemented - * REAL functions : - * NCR5380_REAL_DMA should be defined if real DMA is to be used. * Note that the DMA setup functions should return the number of bytes * that they were able to program the controller for. * - * Also note that generic i386/PC versions of these macros are - * available as NCR5380_i386_dma_write_setup, - * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual. - * * NCR5380_dma_write_setup(instance, src, count) - initialize * NCR5380_dma_read_setup(instance, dst, count) - initialize * NCR5380_dma_residual(instance); - residual count @@ -486,12 +466,6 @@ static void prepare_info(struct Scsi_Host *instance) #ifdef DIFFERENTIAL "DIFFERENTIAL " #endif -#ifdef REAL_DMA - "REAL_DMA " -#endif -#ifdef REAL_DMA_POLL - "REAL_DMA_POLL " -#endif #ifdef PARITY "PARITY " #endif @@ -551,9 +525,8 @@ static int NCR5380_init(struct Scsi_Host *instance, int flags) hostdata->id_higher_mask |= i; for (i = 0; i < 8; ++i) hostdata->busy[i] = 0; -#ifdef REAL_DMA - hostdata->dmalen = 0; -#endif + hostdata->dma_len = 0; + spin_lock_init(&hostdata->lock); hostdata->connected = NULL; hostdata->sensing = NULL; @@ -850,11 +823,7 @@ static void NCR5380_main(struct work_struct *work) requeue_cmd(instance, cmd); } } - if (hostdata->connected -#ifdef REAL_DMA - && !hostdata->dmalen -#endif - ) { + if (hostdata->connected && !hostdata->dma_len) { dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n"); NCR5380_information_transfer(instance); done = 0; @@ -919,34 +888,6 @@ static irqreturn_t NCR5380_intr(int irq, void *dev_id) dsprintk(NDEBUG_INTR, instance, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n", irq, basr, sr, mr); -#if defined(REAL_DMA) - if ((mr & MR_DMA_MODE) || (mr & MR_MONITOR_BSY)) { - /* Probably End of DMA, Phase Mismatch or Loss of BSY. - * We ack IRQ after clearing Mode Register. Workarounds - * for End of DMA errata need to happen in DMA Mode. - */ - - dsprintk(NDEBUG_INTR, instance, "interrupt in DMA mode\n"); - - int transferred; - - if (!hostdata->connected) - panic("scsi%d : DMA interrupt with no connected cmd\n", - instance->hostno); - - transferred = hostdata->dmalen - NCR5380_dma_residual(instance); - hostdata->connected->SCp.this_residual -= transferred; - hostdata->connected->SCp.ptr += transferred; - hostdata->dmalen = 0; - - /* FIXME: we need to poll briefly then defer a workqueue task ! */ - NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2 * HZ); - - NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); - NCR5380_write(MODE_REG, MR_BASE); - NCR5380_read(RESET_PARITY_INTERRUPT_REG); - } else -#endif /* REAL_DMA */ if ((NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_mask) && (sr & (SR_SEL | SR_IO | SR_BSY | SR_RST)) == (SR_SEL | SR_IO)) { /* Probably reselected */ @@ -1495,7 +1436,7 @@ timeout: return -1; } -#if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL) +#if defined(PSEUDO_DMA) /* * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, * unsigned char *phase, int *count, unsigned char **data) @@ -1525,34 +1466,14 @@ static int NCR5380_transfer_dma(struct Scsi_Host *instance, register unsigned char *d = *data; unsigned char tmp; int foo; -#if defined(REAL_DMA_POLL) - int cnt, toPIO; - unsigned char saved_data = 0, overrun = 0, residue; -#endif if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) { *phase = tmp; return -1; } -#if defined(REAL_DMA) || defined(REAL_DMA_POLL) - if (p & SR_IO) { - if (!(hostdata->flags & FLAG_NO_DMA_FIXUPS)) - c -= 2; - } - hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c); - - dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n", - (p & SR_IO) ? "receive" : "send", c, *data); -#endif NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); -#ifdef REAL_DMA - NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY | - MR_ENABLE_EOP_INTR); -#elif defined(REAL_DMA_POLL) - NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY); -#else /* * Note : on my sample board, watch-dog timeouts occurred when interrupts * were not disabled for the duration of a single DMA transfer, from @@ -1564,7 +1485,6 @@ static int NCR5380_transfer_dma(struct Scsi_Host *instance, MR_ENABLE_EOP_INTR); else NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY); -#endif /* def REAL_DMA */ dprintk(NDEBUG_DMA, "scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG)); @@ -1584,14 +1504,8 @@ static int NCR5380_transfer_dma(struct Scsi_Host *instance, io_recovery_delay(1); } -#if defined(REAL_DMA_POLL) - do { - tmp = NCR5380_read(BUS_AND_STATUS_REG); - } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER))); - /* - * At this point, either we've completed DMA, or we have a phase mismatch, - * or we've unexpectedly lost BUSY (which is a real error). + * A note regarding the DMA errata workarounds for early NMOS silicon. * * For DMA sends, we want to wait until the last byte has been * transferred out over the bus before we turn off DMA mode. Alas, there @@ -1618,79 +1532,18 @@ static int NCR5380_transfer_dma(struct Scsi_Host *instance, * properly, or the target switches to MESSAGE IN phase to signal a * disconnection (either operation bringing the DMA to a clean halt). * However, in order to handle scatter-receive, we must work around the - * problem. The chosen fix is to DMA N-2 bytes, then check for the + * problem. The chosen fix is to DMA fewer bytes, then check for the * condition before taking the NCR5380 out of DMA mode. One or two extra * bytes are transferred via PIO as necessary to fill out the original * request. */ if (p & SR_IO) { - if (!(hostdata->flags & FLAG_NO_DMA_FIXUPS)) { - udelay(10); - if ((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == - (BASR_PHASE_MATCH | BASR_ACK)) { - saved_data = NCR5380_read(INPUT_DATA_REGISTER); - overrun = 1; - } - } - } else { - int limit = 100; - while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) { - if (!(tmp & BASR_PHASE_MATCH)) - break; - if (--limit < 0) - break; - } - } - - dsprintk(NDEBUG_DMA, "polled DMA transfer complete, basr 0x%02x, sr 0x%02x\n", - tmp, NCR5380_read(STATUS_REG)); - - NCR5380_write(MODE_REG, MR_BASE); - NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); - - residue = NCR5380_dma_residual(instance); - c -= residue; - *count -= c; - *data += c; - *phase = NCR5380_read(STATUS_REG) & PHASE_MASK; - - if (!(hostdata->flags & FLAG_NO_DMA_FIXUPS) && - *phase == p && (p & SR_IO) && residue == 0) { - if (overrun) { - dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n"); - **data = saved_data; - *data += 1; - *count -= 1; - cnt = toPIO = 1; - } else { - printk("No overrun??\n"); - cnt = toPIO = 2; - } - dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%X\n", cnt, *data); - NCR5380_transfer_pio(instance, phase, &cnt, data); - *count -= toPIO - cnt; - } - - dprintk(NDEBUG_DMA, "Return with data ptr = 0x%X, count %d, last 0x%X, next 0x%X\n", *data, *count, *(*data + *count - 1), *(*data + *count)); - return 0; - -#elif defined(REAL_DMA) - return 0; -#else /* defined(REAL_DMA_POLL) */ - if (p & SR_IO) { foo = NCR5380_pread(instance, d, hostdata->flags & FLAG_NO_DMA_FIXUP ? c : c - 1); if (!foo && !(hostdata->flags & FLAG_NO_DMA_FIXUP)) { /* - * We can't disable DMA mode after successfully transferring - * what we plan to be the last byte, since that would open up - * a race condition where if the target asserted REQ before - * we got the DMA mode reset, the NCR5380 would have latched - * an additional byte into the INPUT DATA register and we'd - * have dropped it. - * - * The workaround was to transfer one fewer bytes than we + * The workaround was to transfer fewer bytes than we * intended to with the pseudo-DMA read function, wait for * the chip to latch the last byte, read it, and then disable * pseudo-DMA mode. @@ -1738,9 +1591,8 @@ static int NCR5380_transfer_dma(struct Scsi_Host *instance, *count = 0; *phase = NCR5380_read(STATUS_REG) & PHASE_MASK; return foo; -#endif /* def REAL_DMA */ } -#endif /* defined(REAL_DMA) | defined(PSEUDO_DMA) */ +#endif /* PSEUDO_DMA */ /* * Function : NCR5380_information_transfer (struct Scsi_Host *instance) @@ -1831,7 +1683,7 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance) * in an unconditional loop. */ -#if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) +#if defined(PSEUDO_DMA) transfersize = 0; if (!cmd->device->borken) transfersize = NCR5380_dma_xfer_len(instance, cmd, phase); @@ -1855,7 +1707,7 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance) } else cmd->SCp.this_residual -= transfersize - len; } else -#endif /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */ +#endif /* PSEUDO_DMA */ { /* Break up transfer into 3 ms chunks, * presuming 6 accesses per handshake. @@ -2202,52 +2054,6 @@ static void NCR5380_reselect(struct Scsi_Host *instance) scmd_id(tmp), tmp->device->lun, tmp->tag); } -/* - * Function : void NCR5380_dma_complete (struct Scsi_Host *instance) - * - * Purpose : called by interrupt handler when DMA finishes or a phase - * mismatch occurs (which would finish the DMA transfer). - * - * Inputs : instance - this instance of the NCR5380. - * - * Returns : pointer to the scsi_cmnd structure for which the I_T_L - * nexus has been reestablished, on failure NULL is returned. - */ - -#ifdef REAL_DMA -static void NCR5380_dma_complete(NCR5380_instance * instance) { - struct NCR5380_hostdata *hostdata = shost_priv(instance); - int transferred; - - /* - * XXX this might not be right. - * - * Wait for final byte to transfer, ie wait for ACK to go false. - * - * We should use the Last Byte Sent bit, unfortunately this is - * not available on the 5380/5381 (only the various CMOS chips) - * - * FIXME: timeout, and need to handle long timeout/irq case - */ - - NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ); - - NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); - - /* - * The only places we should see a phase mismatch and have to send - * data from the same set of pointers will be the data transfer - * phases. So, residual, requested length are only important here. - */ - - if (!(hostdata->connected->SCp.phase & SR_CD)) { - transferred = instance->dmalen - NCR5380_dma_residual(); - hostdata->connected->SCp.this_residual -= transferred; - hostdata->connected->SCp.ptr += transferred; - } -} -#endif /* def REAL_DMA */ - /** * list_find_cmd - test for presence of a command in a linked list * @haystack: list of commands @@ -2359,9 +2165,7 @@ static int NCR5380_abort(struct scsi_cmnd *cmd) if (hostdata->connected == cmd) { dsprintk(NDEBUG_ABORT, instance, "abort: cmd %p is connected\n", cmd); hostdata->connected = NULL; -#ifdef REAL_DMA hostdata->dma_len = 0; -#endif if (do_abort(instance)) { set_host_byte(cmd, DID_ERROR); complete_cmd(instance, cmd); @@ -2464,9 +2268,7 @@ static int NCR5380_bus_reset(struct scsi_cmnd *cmd) for (i = 0; i < 8; ++i) hostdata->busy[i] = 0; -#ifdef REAL_DMA hostdata->dma_len = 0; -#endif queue_work(hostdata->work_q, &hostdata->main_task); spin_unlock_irqrestore(&hostdata->lock, flags); |