| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * NCR 5380 generic driver routines. These should make it *trivial* |
| * to implement 5380 SCSI drivers under Linux with a non-trantor |
| * architecture. |
| * |
| * Note that these routines also work with NR53c400 family chips. |
| * |
| * Copyright 1993, Drew Eckhardt |
| * Visionary Computing |
| * (Unix and Linux consulting and custom programming) |
| * drew@colorado.edu |
| * +1 (303) 666-5836 |
| * |
| * For more information, please consult |
| * |
| * NCR 5380 Family |
| * SCSI Protocol Controller |
| * Databook |
| * |
| * NCR Microelectronics |
| * 1635 Aeroplaza Drive |
| * Colorado Springs, CO 80916 |
| * 1+ (719) 578-3400 |
| * 1+ (800) 334-5454 |
| */ |
| |
| /* |
| * With contributions from Ray Van Tassle, Ingmar Baumgart, |
| * Ronald van Cuijlenborg, Alan Cox and others. |
| */ |
| |
| /* Ported to Atari by Roman Hodek and others. */ |
| |
| /* Adapted for the Sun 3 by Sam Creasey. */ |
| |
| /* |
| * Design |
| * |
| * This is a generic 5380 driver. To use it on a different platform, |
| * one simply writes appropriate system specific macros (ie, data |
| * transfer - some PC's will use the I/O bus, 68K's must use |
| * memory mapped) and drops this file in their 'C' wrapper. |
| * |
| * As far as command queueing, two queues are maintained for |
| * each 5380 in the system - commands that haven't been issued yet, |
| * and commands that are currently executing. This means that an |
| * unlimited number of commands may be queued, letting |
| * more commands propagate from the higher driver levels giving higher |
| * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported, |
| * allowing multiple commands to propagate all the way to a SCSI-II device |
| * while a command is already executing. |
| * |
| * |
| * Issues specific to the NCR5380 : |
| * |
| * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead |
| * piece of hardware that requires you to sit in a loop polling for |
| * the REQ signal as long as you are connected. Some devices are |
| * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect |
| * while doing long seek operations. [...] These |
| * broken devices are the exception rather than the rule and I'd rather |
| * spend my time optimizing for the normal case. |
| * |
| * Architecture : |
| * |
| * At the heart of the design is a coroutine, NCR5380_main, |
| * which is started from a workqueue for each NCR5380 host in the |
| * system. It attempts to establish I_T_L or I_T_L_Q nexuses by |
| * removing the commands from the issue queue and calling |
| * NCR5380_select() if a nexus is not established. |
| * |
| * Once a nexus is established, the NCR5380_information_transfer() |
| * phase goes through the various phases as instructed by the target. |
| * if the target goes into MSG IN and sends a DISCONNECT message, |
| * the command structure is placed into the per instance disconnected |
| * queue, and NCR5380_main tries to find more work. If the target is |
| * idle for too long, the system will try to sleep. |
| * |
| * If a command has disconnected, eventually an interrupt will trigger, |
| * calling NCR5380_intr() which will in turn call NCR5380_reselect |
| * to reestablish a nexus. This will run main if necessary. |
| * |
| * On command termination, the done function will be called as |
| * appropriate. |
| * |
| * SCSI pointers are maintained in the SCp field of SCSI command |
| * structures, being initialized after the command is connected |
| * in NCR5380_select, and set as appropriate in NCR5380_information_transfer. |
| * Note that in violation of the standard, an implicit SAVE POINTERS operation |
| * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS. |
| */ |
| |
| /* |
| * Using this file : |
| * This file a skeleton Linux SCSI driver for the NCR 5380 series |
| * of chips. To use it, you write an architecture specific functions |
| * and macros and include this file in your driver. |
| * |
| * These macros MUST be defined : |
| * |
| * NCR5380_read(register) - read from the specified register |
| * |
| * NCR5380_write(register, value) - write to the specific register |
| * |
| * NCR5380_implementation_fields - additional fields needed for this |
| * specific implementation of the NCR5380 |
| * |
| * Either real DMA *or* pseudo DMA may be implemented |
| * |
| * NCR5380_dma_xfer_len - determine size of DMA/PDMA transfer |
| * NCR5380_dma_send_setup - execute DMA/PDMA from memory to 5380 |
| * NCR5380_dma_recv_setup - execute DMA/PDMA from 5380 to memory |
| * NCR5380_dma_residual - residual byte count |
| * |
| * The generic driver is initialized by calling NCR5380_init(instance), |
| * after setting the appropriate host specific fields and ID. |
| */ |
| |
| #ifndef NCR5380_io_delay |
| #define NCR5380_io_delay(x) |
| #endif |
| |
| #ifndef NCR5380_acquire_dma_irq |
| #define NCR5380_acquire_dma_irq(x) (1) |
| #endif |
| |
| #ifndef NCR5380_release_dma_irq |
| #define NCR5380_release_dma_irq(x) |
| #endif |
| |
| static unsigned int disconnect_mask = ~0; |
| module_param(disconnect_mask, int, 0444); |
| |
| static int do_abort(struct Scsi_Host *); |
| static void do_reset(struct Scsi_Host *); |
| static void bus_reset_cleanup(struct Scsi_Host *); |
| |
| /** |
| * initialize_SCp - init the scsi pointer field |
| * @cmd: command block to set up |
| * |
| * Set up the internal fields in the SCSI command. |
| */ |
| |
| static inline void initialize_SCp(struct scsi_cmnd *cmd) |
| { |
| /* |
| * Initialize the Scsi Pointer field so that all of the commands in the |
| * various queues are valid. |
| */ |
| |
| if (scsi_bufflen(cmd)) { |
| cmd->SCp.buffer = scsi_sglist(cmd); |
| cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); |
| cmd->SCp.this_residual = cmd->SCp.buffer->length; |
| } else { |
| cmd->SCp.buffer = NULL; |
| cmd->SCp.ptr = NULL; |
| cmd->SCp.this_residual = 0; |
| } |
| |
| cmd->SCp.Status = 0; |
| cmd->SCp.Message = 0; |
| } |
| |
| static inline void advance_sg_buffer(struct scsi_cmnd *cmd) |
| { |
| struct scatterlist *s = cmd->SCp.buffer; |
| |
| if (!cmd->SCp.this_residual && s && !sg_is_last(s)) { |
| cmd->SCp.buffer = sg_next(s); |
| cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); |
| cmd->SCp.this_residual = cmd->SCp.buffer->length; |
| } |
| } |
| |
| static inline void set_resid_from_SCp(struct scsi_cmnd *cmd) |
| { |
| int resid = cmd->SCp.this_residual; |
| struct scatterlist *s = cmd->SCp.buffer; |
| |
| if (s) |
| while (!sg_is_last(s)) { |
| s = sg_next(s); |
| resid += s->length; |
| } |
| scsi_set_resid(cmd, resid); |
| } |
| |
| /** |
| * NCR5380_poll_politely2 - wait for two chip register values |
| * @hostdata: host private data |
| * @reg1: 5380 register to poll |
| * @bit1: Bitmask to check |
| * @val1: Expected value |
| * @reg2: Second 5380 register to poll |
| * @bit2: Second bitmask to check |
| * @val2: Second expected value |
| * @wait: Time-out in jiffies |
| * |
| * Polls the chip in a reasonably efficient manner waiting for an |
| * event to occur. After a short quick poll we begin to yield the CPU |
| * (if possible). In irq contexts the time-out is arbitrarily limited. |
| * Callers may hold locks as long as they are held in irq mode. |
| * |
| * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT. |
| */ |
| |
| static int NCR5380_poll_politely2(struct NCR5380_hostdata *hostdata, |
| unsigned int reg1, u8 bit1, u8 val1, |
| unsigned int reg2, u8 bit2, u8 val2, |
| unsigned long wait) |
| { |
| unsigned long n = hostdata->poll_loops; |
| unsigned long deadline = jiffies + wait; |
| |
| do { |
| if ((NCR5380_read(reg1) & bit1) == val1) |
| return 0; |
| if ((NCR5380_read(reg2) & bit2) == val2) |
| return 0; |
| cpu_relax(); |
| } while (n--); |
| |
| if (irqs_disabled() || in_interrupt()) |
| return -ETIMEDOUT; |
| |
| /* Repeatedly sleep for 1 ms until deadline */ |
| while (time_is_after_jiffies(deadline)) { |
| schedule_timeout_uninterruptible(1); |
| if ((NCR5380_read(reg1) & bit1) == val1) |
| return 0; |
| if ((NCR5380_read(reg2) & bit2) == val2) |
| return 0; |
| } |
| |
| return -ETIMEDOUT; |
| } |
| |
| #if NDEBUG |
| static struct { |
| unsigned char mask; |
| const char *name; |
| } signals[] = { |
| {SR_DBP, "PARITY"}, |
| {SR_RST, "RST"}, |
| {SR_BSY, "BSY"}, |
| {SR_REQ, "REQ"}, |
| {SR_MSG, "MSG"}, |
| {SR_CD, "CD"}, |
| {SR_IO, "IO"}, |
| {SR_SEL, "SEL"}, |
| {0, NULL} |
| }, |
| basrs[] = { |
| {BASR_END_DMA_TRANSFER, "END OF DMA"}, |
| {BASR_DRQ, "DRQ"}, |
| {BASR_PARITY_ERROR, "PARITY ERROR"}, |
| {BASR_IRQ, "IRQ"}, |
| {BASR_PHASE_MATCH, "PHASE MATCH"}, |
| {BASR_BUSY_ERROR, "BUSY ERROR"}, |
| {BASR_ATN, "ATN"}, |
| {BASR_ACK, "ACK"}, |
| {0, NULL} |
| }, |
| icrs[] = { |
| {ICR_ASSERT_RST, "ASSERT RST"}, |
| {ICR_ARBITRATION_PROGRESS, "ARB. IN PROGRESS"}, |
| {ICR_ARBITRATION_LOST, "LOST ARB."}, |
| {ICR_ASSERT_ACK, "ASSERT ACK"}, |
| {ICR_ASSERT_BSY, "ASSERT BSY"}, |
| {ICR_ASSERT_SEL, "ASSERT SEL"}, |
| {ICR_ASSERT_ATN, "ASSERT ATN"}, |
| {ICR_ASSERT_DATA, "ASSERT DATA"}, |
| {0, NULL} |
| }, |
| mrs[] = { |
| {MR_BLOCK_DMA_MODE, "BLOCK DMA MODE"}, |
| {MR_TARGET, "TARGET"}, |
| {MR_ENABLE_PAR_CHECK, "PARITY CHECK"}, |
| {MR_ENABLE_PAR_INTR, "PARITY INTR"}, |
| {MR_ENABLE_EOP_INTR, "EOP INTR"}, |
| {MR_MONITOR_BSY, "MONITOR BSY"}, |
| {MR_DMA_MODE, "DMA MODE"}, |
| {MR_ARBITRATE, "ARBITRATE"}, |
| {0, NULL} |
| }; |
| |
| /** |
| * NCR5380_print - print scsi bus signals |
| * @instance: adapter state to dump |
| * |
| * Print the SCSI bus signals for debugging purposes |
| */ |
| |
| static void NCR5380_print(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| unsigned char status, basr, mr, icr, i; |
| |
| status = NCR5380_read(STATUS_REG); |
| mr = NCR5380_read(MODE_REG); |
| icr = NCR5380_read(INITIATOR_COMMAND_REG); |
| basr = NCR5380_read(BUS_AND_STATUS_REG); |
| |
| printk(KERN_DEBUG "SR = 0x%02x : ", status); |
| for (i = 0; signals[i].mask; ++i) |
| if (status & signals[i].mask) |
| printk(KERN_CONT "%s, ", signals[i].name); |
| printk(KERN_CONT "\nBASR = 0x%02x : ", basr); |
| for (i = 0; basrs[i].mask; ++i) |
| if (basr & basrs[i].mask) |
| printk(KERN_CONT "%s, ", basrs[i].name); |
| printk(KERN_CONT "\nICR = 0x%02x : ", icr); |
| for (i = 0; icrs[i].mask; ++i) |
| if (icr & icrs[i].mask) |
| printk(KERN_CONT "%s, ", icrs[i].name); |
| printk(KERN_CONT "\nMR = 0x%02x : ", mr); |
| for (i = 0; mrs[i].mask; ++i) |
| if (mr & mrs[i].mask) |
| printk(KERN_CONT "%s, ", mrs[i].name); |
| printk(KERN_CONT "\n"); |
| } |
| |
| static struct { |
| unsigned char value; |
| const char *name; |
| } phases[] = { |
| {PHASE_DATAOUT, "DATAOUT"}, |
| {PHASE_DATAIN, "DATAIN"}, |
| {PHASE_CMDOUT, "CMDOUT"}, |
| {PHASE_STATIN, "STATIN"}, |
| {PHASE_MSGOUT, "MSGOUT"}, |
| {PHASE_MSGIN, "MSGIN"}, |
| {PHASE_UNKNOWN, "UNKNOWN"} |
| }; |
| |
| /** |
| * NCR5380_print_phase - show SCSI phase |
| * @instance: adapter to dump |
| * |
| * Print the current SCSI phase for debugging purposes |
| */ |
| |
| static void NCR5380_print_phase(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| unsigned char status; |
| int i; |
| |
| status = NCR5380_read(STATUS_REG); |
| if (!(status & SR_REQ)) |
| shost_printk(KERN_DEBUG, instance, "REQ not asserted, phase unknown.\n"); |
| else { |
| for (i = 0; (phases[i].value != PHASE_UNKNOWN) && |
| (phases[i].value != (status & PHASE_MASK)); ++i) |
| ; |
| shost_printk(KERN_DEBUG, instance, "phase %s\n", phases[i].name); |
| } |
| } |
| #endif |
| |
| /** |
| * NCR5380_info - report driver and host information |
| * @instance: relevant scsi host instance |
| * |
| * For use as the host template info() handler. |
| */ |
| |
| static const char *NCR5380_info(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| |
| return hostdata->info; |
| } |
| |
| /** |
| * NCR5380_init - initialise an NCR5380 |
| * @instance: adapter to configure |
| * @flags: control flags |
| * |
| * Initializes *instance and corresponding 5380 chip, |
| * with flags OR'd into the initial flags value. |
| * |
| * Notes : I assume that the host, hostno, and id bits have been |
| * set correctly. I don't care about the irq and other fields. |
| * |
| * Returns 0 for success |
| */ |
| |
| static int NCR5380_init(struct Scsi_Host *instance, int flags) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| int i; |
| unsigned long deadline; |
| unsigned long accesses_per_ms; |
| |
| instance->max_lun = 7; |
| |
| hostdata->host = instance; |
| hostdata->id_mask = 1 << instance->this_id; |
| hostdata->id_higher_mask = 0; |
| for (i = hostdata->id_mask; i <= 0x80; i <<= 1) |
| if (i > hostdata->id_mask) |
| hostdata->id_higher_mask |= i; |
| for (i = 0; i < 8; ++i) |
| hostdata->busy[i] = 0; |
| hostdata->dma_len = 0; |
| |
| spin_lock_init(&hostdata->lock); |
| hostdata->connected = NULL; |
| hostdata->sensing = NULL; |
| INIT_LIST_HEAD(&hostdata->autosense); |
| INIT_LIST_HEAD(&hostdata->unissued); |
| INIT_LIST_HEAD(&hostdata->disconnected); |
| |
| hostdata->flags = flags; |
| |
| INIT_WORK(&hostdata->main_task, NCR5380_main); |
| hostdata->work_q = alloc_workqueue("ncr5380_%d", |
| WQ_UNBOUND | WQ_MEM_RECLAIM, |
| 1, instance->host_no); |
| if (!hostdata->work_q) |
| return -ENOMEM; |
| |
| snprintf(hostdata->info, sizeof(hostdata->info), |
| "%s, irq %d, io_port 0x%lx, base 0x%lx, can_queue %d, cmd_per_lun %d, sg_tablesize %d, this_id %d, flags { %s%s%s}", |
| instance->hostt->name, instance->irq, hostdata->io_port, |
| hostdata->base, instance->can_queue, instance->cmd_per_lun, |
| instance->sg_tablesize, instance->this_id, |
| hostdata->flags & FLAG_DMA_FIXUP ? "DMA_FIXUP " : "", |
| hostdata->flags & FLAG_NO_PSEUDO_DMA ? "NO_PSEUDO_DMA " : "", |
| hostdata->flags & FLAG_TOSHIBA_DELAY ? "TOSHIBA_DELAY " : ""); |
| |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| NCR5380_write(MODE_REG, MR_BASE); |
| NCR5380_write(TARGET_COMMAND_REG, 0); |
| NCR5380_write(SELECT_ENABLE_REG, 0); |
| |
| /* Calibrate register polling loop */ |
| i = 0; |
| deadline = jiffies + 1; |
| do { |
| cpu_relax(); |
| } while (time_is_after_jiffies(deadline)); |
| deadline += msecs_to_jiffies(256); |
| do { |
| NCR5380_read(STATUS_REG); |
| ++i; |
| cpu_relax(); |
| } while (time_is_after_jiffies(deadline)); |
| accesses_per_ms = i / 256; |
| hostdata->poll_loops = NCR5380_REG_POLL_TIME * accesses_per_ms / 2; |
| |
| return 0; |
| } |
| |
| /** |
| * NCR5380_maybe_reset_bus - Detect and correct bus wedge problems. |
| * @instance: adapter to check |
| * |
| * If the system crashed, it may have crashed with a connected target and |
| * the SCSI bus busy. Check for BUS FREE phase. If not, try to abort the |
| * currently established nexus, which we know nothing about. Failing that |
| * do a bus reset. |
| * |
| * Note that a bus reset will cause the chip to assert IRQ. |
| * |
| * Returns 0 if successful, otherwise -ENXIO. |
| */ |
| |
| static int NCR5380_maybe_reset_bus(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| int pass; |
| |
| for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) { |
| switch (pass) { |
| case 1: |
| case 3: |
| case 5: |
| shost_printk(KERN_ERR, instance, "SCSI bus busy, waiting up to five seconds\n"); |
| NCR5380_poll_politely(hostdata, |
| STATUS_REG, SR_BSY, 0, 5 * HZ); |
| break; |
| case 2: |
| shost_printk(KERN_ERR, instance, "bus busy, attempting abort\n"); |
| do_abort(instance); |
| break; |
| case 4: |
| shost_printk(KERN_ERR, instance, "bus busy, attempting reset\n"); |
| do_reset(instance); |
| /* Wait after a reset; the SCSI standard calls for |
| * 250ms, we wait 500ms to be on the safe side. |
| * But some Toshiba CD-ROMs need ten times that. |
| */ |
| if (hostdata->flags & FLAG_TOSHIBA_DELAY) |
| msleep(2500); |
| else |
| msleep(500); |
| break; |
| case 6: |
| shost_printk(KERN_ERR, instance, "bus locked solid\n"); |
| return -ENXIO; |
| } |
| } |
| return 0; |
| } |
| |
| /** |
| * NCR5380_exit - remove an NCR5380 |
| * @instance: adapter to remove |
| * |
| * Assumes that no more work can be queued (e.g. by NCR5380_intr). |
| */ |
| |
| static void NCR5380_exit(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| |
| cancel_work_sync(&hostdata->main_task); |
| destroy_workqueue(hostdata->work_q); |
| } |
| |
| /** |
| * complete_cmd - finish processing a command and return it to the SCSI ML |
| * @instance: the host instance |
| * @cmd: command to complete |
| */ |
| |
| static void complete_cmd(struct Scsi_Host *instance, |
| struct scsi_cmnd *cmd) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| |
| dsprintk(NDEBUG_QUEUES, instance, "complete_cmd: cmd %p\n", cmd); |
| |
| if (hostdata->sensing == cmd) { |
| /* Autosense processing ends here */ |
| if (status_byte(cmd->result) != GOOD) { |
| scsi_eh_restore_cmnd(cmd, &hostdata->ses); |
| } else { |
| scsi_eh_restore_cmnd(cmd, &hostdata->ses); |
| set_driver_byte(cmd, DRIVER_SENSE); |
| } |
| hostdata->sensing = NULL; |
| } |
| |
| cmd->scsi_done(cmd); |
| } |
| |
| /** |
| * NCR5380_queue_command - queue a command |
| * @instance: the relevant SCSI adapter |
| * @cmd: SCSI command |
| * |
| * cmd is added to the per-instance issue queue, with minor |
| * twiddling done to the host specific fields of cmd. If the |
| * main coroutine is not running, it is restarted. |
| */ |
| |
| static int NCR5380_queue_command(struct Scsi_Host *instance, |
| struct scsi_cmnd *cmd) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd); |
| unsigned long flags; |
| |
| #if (NDEBUG & NDEBUG_NO_WRITE) |
| switch (cmd->cmnd[0]) { |
| case WRITE_6: |
| case WRITE_10: |
| shost_printk(KERN_DEBUG, instance, "WRITE attempted with NDEBUG_NO_WRITE set\n"); |
| cmd->result = (DID_ERROR << 16); |
| cmd->scsi_done(cmd); |
| return 0; |
| } |
| #endif /* (NDEBUG & NDEBUG_NO_WRITE) */ |
| |
| cmd->result = 0; |
| |
| if (!NCR5380_acquire_dma_irq(instance)) |
| return SCSI_MLQUEUE_HOST_BUSY; |
| |
| spin_lock_irqsave(&hostdata->lock, flags); |
| |
| /* |
| * Insert the cmd into the issue queue. Note that REQUEST SENSE |
| * commands are added to the head of the queue since any command will |
| * clear the contingent allegiance condition that exists and the |
| * sense data is only guaranteed to be valid while the condition exists. |
| */ |
| |
| if (cmd->cmnd[0] == REQUEST_SENSE) |
| list_add(&ncmd->list, &hostdata->unissued); |
| else |
| list_add_tail(&ncmd->list, &hostdata->unissued); |
| |
| spin_unlock_irqrestore(&hostdata->lock, flags); |
| |
| dsprintk(NDEBUG_QUEUES, instance, "command %p added to %s of queue\n", |
| cmd, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"); |
| |
| /* Kick off command processing */ |
| queue_work(hostdata->work_q, &hostdata->main_task); |
| return 0; |
| } |
| |
| static inline void maybe_release_dma_irq(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| |
| /* Caller does the locking needed to set & test these data atomically */ |
| if (list_empty(&hostdata->disconnected) && |
| list_empty(&hostdata->unissued) && |
| list_empty(&hostdata->autosense) && |
| !hostdata->connected && |
| !hostdata->selecting) { |
| NCR5380_release_dma_irq(instance); |
| } |
| } |
| |
| /** |
| * dequeue_next_cmd - dequeue a command for processing |
| * @instance: the scsi host instance |
| * |
| * Priority is given to commands on the autosense queue. These commands |
| * need autosense because of a CHECK CONDITION result. |
| * |
| * Returns a command pointer if a command is found for a target that is |
| * not already busy. Otherwise returns NULL. |
| */ |
| |
| static struct scsi_cmnd *dequeue_next_cmd(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| struct NCR5380_cmd *ncmd; |
| struct scsi_cmnd *cmd; |
| |
| if (hostdata->sensing || list_empty(&hostdata->autosense)) { |
| list_for_each_entry(ncmd, &hostdata->unissued, list) { |
| cmd = NCR5380_to_scmd(ncmd); |
| dsprintk(NDEBUG_QUEUES, instance, "dequeue: cmd=%p target=%d busy=0x%02x lun=%llu\n", |
| cmd, scmd_id(cmd), hostdata->busy[scmd_id(cmd)], cmd->device->lun); |
| |
| if (!(hostdata->busy[scmd_id(cmd)] & (1 << cmd->device->lun))) { |
| list_del(&ncmd->list); |
| dsprintk(NDEBUG_QUEUES, instance, |
| "dequeue: removed %p from issue queue\n", cmd); |
| return cmd; |
| } |
| } |
| } else { |
| /* Autosense processing begins here */ |
| ncmd = list_first_entry(&hostdata->autosense, |
| struct NCR5380_cmd, list); |
| list_del(&ncmd->list); |
| cmd = NCR5380_to_scmd(ncmd); |
| dsprintk(NDEBUG_QUEUES, instance, |
| "dequeue: removed %p from autosense queue\n", cmd); |
| scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0); |
| hostdata->sensing = cmd; |
| return cmd; |
| } |
| return NULL; |
| } |
| |
| static void requeue_cmd(struct Scsi_Host *instance, struct scsi_cmnd *cmd) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd); |
| |
| if (hostdata->sensing == cmd) { |
| scsi_eh_restore_cmnd(cmd, &hostdata->ses); |
| list_add(&ncmd->list, &hostdata->autosense); |
| hostdata->sensing = NULL; |
| } else |
| list_add(&ncmd->list, &hostdata->unissued); |
| } |
| |
| /** |
| * NCR5380_main - NCR state machines |
| * |
| * NCR5380_main is a coroutine that runs as long as more work can |
| * be done on the NCR5380 host adapters in a system. Both |
| * NCR5380_queue_command() and NCR5380_intr() will try to start it |
| * in case it is not running. |
| */ |
| |
| static void NCR5380_main(struct work_struct *work) |
| { |
| struct NCR5380_hostdata *hostdata = |
| container_of(work, struct NCR5380_hostdata, main_task); |
| struct Scsi_Host *instance = hostdata->host; |
| int done; |
| |
| do { |
| done = 1; |
| |
| spin_lock_irq(&hostdata->lock); |
| while (!hostdata->connected && !hostdata->selecting) { |
| struct scsi_cmnd *cmd = dequeue_next_cmd(instance); |
| |
| if (!cmd) |
| break; |
| |
| dsprintk(NDEBUG_MAIN, instance, "main: dequeued %p\n", cmd); |
| |
| /* |
| * Attempt to establish an I_T_L nexus here. |
| * On success, instance->hostdata->connected is set. |
| * On failure, we must add the command back to the |
| * issue queue so we can keep trying. |
| */ |
| /* |
| * REQUEST SENSE commands are issued without tagged |
| * queueing, even on SCSI-II devices because the |
| * contingent allegiance condition exists for the |
| * entire unit. |
| */ |
| |
| if (!NCR5380_select(instance, cmd)) { |
| dsprintk(NDEBUG_MAIN, instance, "main: select complete\n"); |
| maybe_release_dma_irq(instance); |
| } else { |
| dsprintk(NDEBUG_MAIN | NDEBUG_QUEUES, instance, |
| "main: select failed, returning %p to queue\n", cmd); |
| requeue_cmd(instance, cmd); |
| } |
| } |
| if (hostdata->connected && !hostdata->dma_len) { |
| dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n"); |
| NCR5380_information_transfer(instance); |
| done = 0; |
| } |
| if (!hostdata->connected) |
| NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); |
| spin_unlock_irq(&hostdata->lock); |
| if (!done) |
| cond_resched(); |
| } while (!done); |
| } |
| |
| /* |
| * NCR5380_dma_complete - finish DMA transfer |
| * @instance: the scsi host instance |
| * |
| * Called by the interrupt handler when DMA finishes or a phase |
| * mismatch occurs (which would end the DMA transfer). |
| */ |
| |
| static void NCR5380_dma_complete(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| int transferred; |
| unsigned char **data; |
| int *count; |
| int saved_data = 0, overrun = 0; |
| unsigned char p; |
| |
| if (hostdata->read_overruns) { |
| p = hostdata->connected->SCp.phase; |
| if (p & SR_IO) { |
| 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_REG); |
| overrun = 1; |
| dsprintk(NDEBUG_DMA, instance, "read overrun handled\n"); |
| } |
| } |
| } |
| |
| #ifdef CONFIG_SUN3 |
| if ((sun3scsi_dma_finish(rq_data_dir(hostdata->connected->request)))) { |
| pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n", |
| instance->host_no); |
| BUG(); |
| } |
| |
| if ((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == |
| (BASR_PHASE_MATCH | BASR_ACK)) { |
| pr_err("scsi%d: BASR %02x\n", instance->host_no, |
| NCR5380_read(BUS_AND_STATUS_REG)); |
| pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n", |
| instance->host_no); |
| BUG(); |
| } |
| #endif |
| |
| NCR5380_write(MODE_REG, MR_BASE); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| NCR5380_read(RESET_PARITY_INTERRUPT_REG); |
| |
| transferred = hostdata->dma_len - NCR5380_dma_residual(hostdata); |
| hostdata->dma_len = 0; |
| |
| data = (unsigned char **)&hostdata->connected->SCp.ptr; |
| count = &hostdata->connected->SCp.this_residual; |
| *data += transferred; |
| *count -= transferred; |
| |
| if (hostdata->read_overruns) { |
| int cnt, toPIO; |
| |
| if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) { |
| cnt = toPIO = hostdata->read_overruns; |
| if (overrun) { |
| dsprintk(NDEBUG_DMA, instance, |
| "Got an input overrun, using saved byte\n"); |
| *(*data)++ = saved_data; |
| (*count)--; |
| cnt--; |
| toPIO--; |
| } |
| if (toPIO > 0) { |
| dsprintk(NDEBUG_DMA, instance, |
| "Doing %d byte PIO to 0x%p\n", cnt, *data); |
| NCR5380_transfer_pio(instance, &p, &cnt, data); |
| *count -= toPIO - cnt; |
| } |
| } |
| } |
| } |
| |
| /** |
| * NCR5380_intr - generic NCR5380 irq handler |
| * @irq: interrupt number |
| * @dev_id: device info |
| * |
| * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses |
| * from the disconnected queue, and restarting NCR5380_main() |
| * as required. |
| * |
| * The chip can assert IRQ in any of six different conditions. The IRQ flag |
| * is then cleared by reading the Reset Parity/Interrupt Register (RPIR). |
| * Three of these six conditions are latched in the Bus and Status Register: |
| * - End of DMA (cleared by ending DMA Mode) |
| * - Parity error (cleared by reading RPIR) |
| * - Loss of BSY (cleared by reading RPIR) |
| * Two conditions have flag bits that are not latched: |
| * - Bus phase mismatch (non-maskable in DMA Mode, cleared by ending DMA Mode) |
| * - Bus reset (non-maskable) |
| * The remaining condition has no flag bit at all: |
| * - Selection/reselection |
| * |
| * Hence, establishing the cause(s) of any interrupt is partly guesswork. |
| * In "The DP8490 and DP5380 Comparison Guide", National Semiconductor |
| * claimed that "the design of the [DP8490] interrupt logic ensures |
| * interrupts will not be lost (they can be on the DP5380)." |
| * The L5380/53C80 datasheet from LOGIC Devices has more details. |
| * |
| * Checking for bus reset by reading RST is futile because of interrupt |
| * latency, but a bus reset will reset chip logic. Checking for parity error |
| * is unnecessary because that interrupt is never enabled. A Loss of BSY |
| * condition will clear DMA Mode. We can tell when this occurs because the |
| * the Busy Monitor interrupt is enabled together with DMA Mode. |
| */ |
| |
| static irqreturn_t __maybe_unused NCR5380_intr(int irq, void *dev_id) |
| { |
| struct Scsi_Host *instance = dev_id; |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| int handled = 0; |
| unsigned char basr; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&hostdata->lock, flags); |
| |
| basr = NCR5380_read(BUS_AND_STATUS_REG); |
| if (basr & BASR_IRQ) { |
| unsigned char mr = NCR5380_read(MODE_REG); |
| unsigned char sr = NCR5380_read(STATUS_REG); |
| |
| dsprintk(NDEBUG_INTR, instance, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n", |
| irq, basr, sr, mr); |
| |
| 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"); |
| |
| if (hostdata->connected) { |
| NCR5380_dma_complete(instance); |
| queue_work(hostdata->work_q, &hostdata->main_task); |
| } else { |
| NCR5380_write(MODE_REG, MR_BASE); |
| NCR5380_read(RESET_PARITY_INTERRUPT_REG); |
| } |
| } else 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 */ |
| NCR5380_write(SELECT_ENABLE_REG, 0); |
| NCR5380_read(RESET_PARITY_INTERRUPT_REG); |
| |
| dsprintk(NDEBUG_INTR, instance, "interrupt with SEL and IO\n"); |
| |
| if (!hostdata->connected) { |
| NCR5380_reselect(instance); |
| queue_work(hostdata->work_q, &hostdata->main_task); |
| } |
| if (!hostdata->connected) |
| NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); |
| } else { |
| /* Probably Bus Reset */ |
| NCR5380_read(RESET_PARITY_INTERRUPT_REG); |
| |
| if (sr & SR_RST) { |
| /* Certainly Bus Reset */ |
| shost_printk(KERN_WARNING, instance, |
| "bus reset interrupt\n"); |
| bus_reset_cleanup(instance); |
| } else { |
| dsprintk(NDEBUG_INTR, instance, "unknown interrupt\n"); |
| } |
| #ifdef SUN3_SCSI_VME |
| dregs->csr |= CSR_DMA_ENABLE; |
| #endif |
| } |
| handled = 1; |
| } else { |
| dsprintk(NDEBUG_INTR, instance, "interrupt without IRQ bit\n"); |
| #ifdef SUN3_SCSI_VME |
| dregs->csr |= CSR_DMA_ENABLE; |
| #endif |
| } |
| |
| spin_unlock_irqrestore(&hostdata->lock, flags); |
| |
| return IRQ_RETVAL(handled); |
| } |
| |
| /** |
| * NCR5380_select - attempt arbitration and selection for a given command |
| * @instance: the Scsi_Host instance |
| * @cmd: the scsi_cmnd to execute |
| * |
| * This routine establishes an I_T_L nexus for a SCSI command. This involves |
| * ARBITRATION, SELECTION and MESSAGE OUT phases and an IDENTIFY message. |
| * |
| * Returns true if the operation should be retried. |
| * Returns false if it should not be retried. |
| * |
| * Side effects : |
| * If bus busy, arbitration failed, etc, NCR5380_select() will exit |
| * with registers as they should have been on entry - ie |
| * SELECT_ENABLE will be set appropriately, the NCR5380 |
| * will cease to drive any SCSI bus signals. |
| * |
| * If successful : the I_T_L nexus will be established, and |
| * hostdata->connected will be set to cmd. |
| * SELECT interrupt will be disabled. |
| * |
| * If failed (no target) : cmd->scsi_done() will be called, and the |
| * cmd->result host byte set to DID_BAD_TARGET. |
| */ |
| |
| static bool NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) |
| __releases(&hostdata->lock) __acquires(&hostdata->lock) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| unsigned char tmp[3], phase; |
| unsigned char *data; |
| int len; |
| int err; |
| bool ret = true; |
| bool can_disconnect = instance->irq != NO_IRQ && |
| cmd->cmnd[0] != REQUEST_SENSE && |
| (disconnect_mask & BIT(scmd_id(cmd))); |
| |
| NCR5380_dprint(NDEBUG_ARBITRATION, instance); |
| dsprintk(NDEBUG_ARBITRATION, instance, "starting arbitration, id = %d\n", |
| instance->this_id); |
| |
| /* |
| * Arbitration and selection phases are slow and involve dropping the |
| * lock, so we have to watch out for EH. An exception handler may |
| * change 'selecting' to NULL. This function will then return false |
| * so that the caller will forget about 'cmd'. (During information |
| * transfer phases, EH may change 'connected' to NULL.) |
| */ |
| hostdata->selecting = cmd; |
| |
| /* |
| * Set the phase bits to 0, otherwise the NCR5380 won't drive the |
| * data bus during SELECTION. |
| */ |
| |
| NCR5380_write(TARGET_COMMAND_REG, 0); |
| |
| /* |
| * Start arbitration. |
| */ |
| |
| NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); |
| NCR5380_write(MODE_REG, MR_ARBITRATE); |
| |
| /* The chip now waits for BUS FREE phase. Then after the 800 ns |
| * Bus Free Delay, arbitration will begin. |
| */ |
| |
| spin_unlock_irq(&hostdata->lock); |
| err = NCR5380_poll_politely2(hostdata, MODE_REG, MR_ARBITRATE, 0, |
| INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, |
| ICR_ARBITRATION_PROGRESS, HZ); |
| spin_lock_irq(&hostdata->lock); |
| if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) { |
| /* Reselection interrupt */ |
| goto out; |
| } |
| if (!hostdata->selecting) { |
| /* Command was aborted */ |
| NCR5380_write(MODE_REG, MR_BASE); |
| return false; |
| } |
| if (err < 0) { |
| NCR5380_write(MODE_REG, MR_BASE); |
| shost_printk(KERN_ERR, instance, |
| "select: arbitration timeout\n"); |
| goto out; |
| } |
| spin_unlock_irq(&hostdata->lock); |
| |
| /* The SCSI-2 arbitration delay is 2.4 us */ |
| udelay(3); |
| |
| /* Check for lost arbitration */ |
| if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || |
| (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || |
| (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) { |
| NCR5380_write(MODE_REG, MR_BASE); |
| dsprintk(NDEBUG_ARBITRATION, instance, "lost arbitration, deasserting MR_ARBITRATE\n"); |
| spin_lock_irq(&hostdata->lock); |
| goto out; |
| } |
| |
| /* After/during arbitration, BSY should be asserted. |
| * IBM DPES-31080 Version S31Q works now |
| * Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) |
| */ |
| NCR5380_write(INITIATOR_COMMAND_REG, |
| ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY); |
| |
| /* |
| * Again, bus clear + bus settle time is 1.2us, however, this is |
| * a minimum so we'll udelay ceil(1.2) |
| */ |
| |
| if (hostdata->flags & FLAG_TOSHIBA_DELAY) |
| udelay(15); |
| else |
| udelay(2); |
| |
| spin_lock_irq(&hostdata->lock); |
| |
| /* NCR5380_reselect() clears MODE_REG after a reselection interrupt */ |
| if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) |
| goto out; |
| |
| if (!hostdata->selecting) { |
| NCR5380_write(MODE_REG, MR_BASE); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| return false; |
| } |
| |
| dsprintk(NDEBUG_ARBITRATION, instance, "won arbitration\n"); |
| |
| /* |
| * Now that we have won arbitration, start Selection process, asserting |
| * the host and target ID's on the SCSI bus. |
| */ |
| |
| NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask | (1 << scmd_id(cmd))); |
| |
| /* |
| * Raise ATN while SEL is true before BSY goes false from arbitration, |
| * since this is the only way to guarantee that we'll get a MESSAGE OUT |
| * phase immediately after selection. |
| */ |
| |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY | |
| ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL); |
| NCR5380_write(MODE_REG, MR_BASE); |
| |
| /* |
| * Reselect interrupts must be turned off prior to the dropping of BSY, |
| * otherwise we will trigger an interrupt. |
| */ |
| NCR5380_write(SELECT_ENABLE_REG, 0); |
| |
| spin_unlock_irq(&hostdata->lock); |
| |
| /* |
| * The initiator shall then wait at least two deskew delays and release |
| * the BSY signal. |
| */ |
| udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */ |
| |
| /* Reset BSY */ |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | |
| ICR_ASSERT_ATN | ICR_ASSERT_SEL); |
| |
| /* |
| * Something weird happens when we cease to drive BSY - looks |
| * like the board/chip is letting us do another read before the |
| * appropriate propagation delay has expired, and we're confusing |
| * a BSY signal from ourselves as the target's response to SELECTION. |
| * |
| * A small delay (the 'C++' frontend breaks the pipeline with an |
| * unnecessary jump, making it work on my 386-33/Trantor T128, the |
| * tighter 'C' code breaks and requires this) solves the problem - |
| * the 1 us delay is arbitrary, and only used because this delay will |
| * be the same on other platforms and since it works here, it should |
| * work there. |
| * |
| * wingel suggests that this could be due to failing to wait |
| * one deskew delay. |
| */ |
| |
| udelay(1); |
| |
| dsprintk(NDEBUG_SELECTION, instance, "selecting target %d\n", scmd_id(cmd)); |
| |
| /* |
| * The SCSI specification calls for a 250 ms timeout for the actual |
| * selection. |
| */ |
| |
| err = NCR5380_poll_politely(hostdata, STATUS_REG, SR_BSY, SR_BSY, |
| msecs_to_jiffies(250)); |
| |
| if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) { |
| spin_lock_irq(&hostdata->lock); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| NCR5380_reselect(instance); |
| shost_printk(KERN_ERR, instance, "reselection after won arbitration?\n"); |
| goto out; |
| } |
| |
| if (err < 0) { |
| spin_lock_irq(&hostdata->lock); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| |
| /* Can't touch cmd if it has been reclaimed by the scsi ML */ |
| if (!hostdata->selecting) |
| return false; |
| |
| cmd->result = DID_BAD_TARGET << 16; |
| complete_cmd(instance, cmd); |
| dsprintk(NDEBUG_SELECTION, instance, |
| "target did not respond within 250ms\n"); |
| ret = false; |
| goto out; |
| } |
| |
| /* |
| * No less than two deskew delays after the initiator detects the |
| * BSY signal is true, it shall release the SEL signal and may |
| * change the DATA BUS. -wingel |
| */ |
| |
| udelay(1); |
| |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); |
| |
| /* |
| * Since we followed the SCSI spec, and raised ATN while SEL |
| * was true but before BSY was false during selection, the information |
| * transfer phase should be a MESSAGE OUT phase so that we can send the |
| * IDENTIFY message. |
| */ |
| |
| /* Wait for start of REQ/ACK handshake */ |
| |
| err = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ); |
| spin_lock_irq(&hostdata->lock); |
| if (err < 0) { |
| shost_printk(KERN_ERR, instance, "select: REQ timeout\n"); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| goto out; |
| } |
| if (!hostdata->selecting) { |
| do_abort(instance); |
| return false; |
| } |
| |
| dsprintk(NDEBUG_SELECTION, instance, "target %d selected, going into MESSAGE OUT phase.\n", |
| scmd_id(cmd)); |
| tmp[0] = IDENTIFY(can_disconnect, cmd->device->lun); |
| |
| len = 1; |
| data = tmp; |
| phase = PHASE_MSGOUT; |
| NCR5380_transfer_pio(instance, &phase, &len, &data); |
| if (len) { |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| cmd->result = DID_ERROR << 16; |
| complete_cmd(instance, cmd); |
| dsprintk(NDEBUG_SELECTION, instance, "IDENTIFY message transfer failed\n"); |
| ret = false; |
| goto out; |
| } |
| |
| dsprintk(NDEBUG_SELECTION, instance, "nexus established.\n"); |
| |
| hostdata->connected = cmd; |
| hostdata->busy[cmd->device->id] |= 1 << cmd->device->lun; |
| |
| #ifdef SUN3_SCSI_VME |
| dregs->csr |= CSR_INTR; |
| #endif |
| |
| initialize_SCp(cmd); |
| |
| ret = false; |
| |
| out: |
| if (!hostdata->selecting) |
| return false; |
| hostdata->selecting = NULL; |
| return ret; |
| } |
| |
| /* |
| * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, |
| * unsigned char *phase, int *count, unsigned char **data) |
| * |
| * Purpose : transfers data in given phase using polled I/O |
| * |
| * Inputs : instance - instance of driver, *phase - pointer to |
| * what phase is expected, *count - pointer to number of |
| * bytes to transfer, **data - pointer to data pointer. |
| * |
| * Returns : -1 when different phase is entered without transferring |
| * maximum number of bytes, 0 if all bytes are transferred or exit |
| * is in same phase. |
| * |
| * Also, *phase, *count, *data are modified in place. |
| * |
| * XXX Note : handling for bus free may be useful. |
| */ |
| |
| /* |
| * Note : this code is not as quick as it could be, however it |
| * IS 100% reliable, and for the actual data transfer where speed |
| * counts, we will always do a pseudo DMA or DMA transfer. |
| */ |
| |
| static int NCR5380_transfer_pio(struct Scsi_Host *instance, |
| unsigned char *phase, int *count, |
| unsigned char **data) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| unsigned char p = *phase, tmp; |
| int c = *count; |
| unsigned char *d = *data; |
| |
| /* |
| * The NCR5380 chip will only drive the SCSI bus when the |
| * phase specified in the appropriate bits of the TARGET COMMAND |
| * REGISTER match the STATUS REGISTER |
| */ |
| |
| NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); |
| |
| do { |
| /* |
| * Wait for assertion of REQ, after which the phase bits will be |
| * valid |
| */ |
| |
| if (NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ) < 0) |
| break; |
| |
| dsprintk(NDEBUG_HANDSHAKE, instance, "REQ asserted\n"); |
| |
| /* Check for phase mismatch */ |
| if ((NCR5380_read(STATUS_REG) & PHASE_MASK) != p) { |
| dsprintk(NDEBUG_PIO, instance, "phase mismatch\n"); |
| NCR5380_dprint_phase(NDEBUG_PIO, instance); |
| break; |
| } |
| |
| /* Do actual transfer from SCSI bus to / from memory */ |
| if (!(p & SR_IO)) |
| NCR5380_write(OUTPUT_DATA_REG, *d); |
| else |
| *d = NCR5380_read(CURRENT_SCSI_DATA_REG); |
| |
| ++d; |
| |
| /* |
| * The SCSI standard suggests that in MSGOUT phase, the initiator |
| * should drop ATN on the last byte of the message phase |
| * after REQ has been asserted for the handshake but before |
| * the initiator raises ACK. |
| */ |
| |
| if (!(p & SR_IO)) { |
| if (!((p & SR_MSG) && c > 1)) { |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); |
| NCR5380_dprint(NDEBUG_PIO, instance); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | |
| ICR_ASSERT_DATA | ICR_ASSERT_ACK); |
| } else { |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | |
| ICR_ASSERT_DATA | ICR_ASSERT_ATN); |
| NCR5380_dprint(NDEBUG_PIO, instance); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | |
| ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK); |
| } |
| } else { |
| NCR5380_dprint(NDEBUG_PIO, instance); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); |
| } |
| |
| if (NCR5380_poll_politely(hostdata, |
| STATUS_REG, SR_REQ, 0, 5 * HZ) < 0) |
| break; |
| |
| dsprintk(NDEBUG_HANDSHAKE, instance, "REQ negated, handshake complete\n"); |
| |
| /* |
| * We have several special cases to consider during REQ/ACK handshaking : |
| * 1. We were in MSGOUT phase, and we are on the last byte of the |
| * message. ATN must be dropped as ACK is dropped. |
| * |
| * 2. We are in a MSGIN phase, and we are on the last byte of the |
| * message. We must exit with ACK asserted, so that the calling |
| * code may raise ATN before dropping ACK to reject the message. |
| * |
| * 3. ACK and ATN are clear and the target may proceed as normal. |
| */ |
| if (!(p == PHASE_MSGIN && c == 1)) { |
| if (p == PHASE_MSGOUT && c > 1) |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); |
| else |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| } |
| } while (--c); |
| |
| dsprintk(NDEBUG_PIO, instance, "residual %d\n", c); |
| |
| *count = c; |
| *data = d; |
| tmp = NCR5380_read(STATUS_REG); |
| /* The phase read from the bus is valid if either REQ is (already) |
| * asserted or if ACK hasn't been released yet. The latter applies if |
| * we're in MSG IN, DATA IN or STATUS and all bytes have been received. |
| */ |
| if ((tmp & SR_REQ) || ((tmp & SR_IO) && c == 0)) |
| *phase = tmp & PHASE_MASK; |
| else |
| *phase = PHASE_UNKNOWN; |
| |
| if (!c || (*phase == p)) |
| return 0; |
| else |
| return -1; |
| } |
| |
| /** |
| * do_reset - issue a reset command |
| * @instance: adapter to reset |
| * |
| * Issue a reset sequence to the NCR5380 and try and get the bus |
| * back into sane shape. |
| * |
| * This clears the reset interrupt flag because there may be no handler for |
| * it. When the driver is initialized, the NCR5380_intr() handler has not yet |
| * been installed. And when in EH we may have released the ST DMA interrupt. |
| */ |
| |
| static void do_reset(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata __maybe_unused *hostdata = shost_priv(instance); |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| NCR5380_write(TARGET_COMMAND_REG, |
| PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK)); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST); |
| udelay(50); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); |
| local_irq_restore(flags); |
| } |
| |
| /** |
| * do_abort - abort the currently established nexus by going to |
| * MESSAGE OUT phase and sending an ABORT message. |
| * @instance: relevant scsi host instance |
| * |
| * Returns 0 on success, negative error code on failure. |
| */ |
| |
| static int do_abort(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| unsigned char *msgptr, phase, tmp; |
| int len; |
| int rc; |
| |
| /* Request message out phase */ |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); |
| |
| /* |
| * Wait for the target to indicate a valid phase by asserting |
| * REQ. Once this happens, we'll have either a MSGOUT phase |
| * and can immediately send the ABORT message, or we'll have some |
| * other phase and will have to source/sink data. |
| * |
| * We really don't care what value was on the bus or what value |
| * the target sees, so we just handshake. |
| */ |
| |
| rc = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, 10 * HZ); |
| if (rc < 0) |
| goto out; |
| |
| tmp = NCR5380_read(STATUS_REG) & PHASE_MASK; |
| |
| NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); |
| |
| if (tmp != PHASE_MSGOUT) { |
| NCR5380_write(INITIATOR_COMMAND_REG, |
| ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK); |
| rc = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, 0, 3 * HZ); |
| if (rc < 0) |
| goto out; |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); |
| } |
| |
| tmp = ABORT; |
| msgptr = &tmp; |
| len = 1; |
| phase = PHASE_MSGOUT; |
| NCR5380_transfer_pio(instance, &phase, &len, &msgptr); |
| if (len) |
| rc = -ENXIO; |
| |
| /* |
| * If we got here, and the command completed successfully, |
| * we're about to go into bus free state. |
| */ |
| |
| out: |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| return rc; |
| } |
| |
| /* |
| * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, |
| * unsigned char *phase, int *count, unsigned char **data) |
| * |
| * Purpose : transfers data in given phase using either real |
| * or pseudo DMA. |
| * |
| * Inputs : instance - instance of driver, *phase - pointer to |
| * what phase is expected, *count - pointer to number of |
| * bytes to transfer, **data - pointer to data pointer. |
| * |
| * Returns : -1 when different phase is entered without transferring |
| * maximum number of bytes, 0 if all bytes or transferred or exit |
| * is in same phase. |
| * |
| * Also, *phase, *count, *data are modified in place. |
| */ |
| |
| |
| static int NCR5380_transfer_dma(struct Scsi_Host *instance, |
| unsigned char *phase, int *count, |
| unsigned char **data) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| int c = *count; |
| unsigned char p = *phase; |
| unsigned char *d = *data; |
| unsigned char tmp; |
| int result = 0; |
| |
| if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) { |
| *phase = tmp; |
| return -1; |
| } |
| |
| hostdata->connected->SCp.phase = p; |
| |
| if (p & SR_IO) { |
| if (hostdata->read_overruns) |
| c -= hostdata->read_overruns; |
| else if (hostdata->flags & FLAG_DMA_FIXUP) |
| --c; |
| } |
| |
| dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n", |
| (p & SR_IO) ? "receive" : "send", c, d); |
| |
| #ifdef CONFIG_SUN3 |
| /* send start chain */ |
| sun3scsi_dma_start(c, *data); |
| #endif |
| |
| NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); |
| NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY | |
| MR_ENABLE_EOP_INTR); |
| |
| if (!(hostdata->flags & FLAG_LATE_DMA_SETUP)) { |
| /* On the Medusa, it is a must to initialize the DMA before |
| * starting the NCR. This is also the cleaner way for the TT. |
| */ |
| if (p & SR_IO) |
| result = NCR5380_dma_recv_setup(hostdata, d, c); |
| else |
| result = NCR5380_dma_send_setup(hostdata, d, c); |
| } |
| |
| /* |
| * On the PAS16 at least I/O recovery delays are not needed here. |
| * Everyone else seems to want them. |
| */ |
| |
| if (p & SR_IO) { |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| NCR5380_io_delay(1); |
| NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); |
| } else { |
| NCR5380_io_delay(1); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); |
| NCR5380_io_delay(1); |
| NCR5380_write(START_DMA_SEND_REG, 0); |
| NCR5380_io_delay(1); |
| } |
| |
| #ifdef CONFIG_SUN3 |
| #ifdef SUN3_SCSI_VME |
| dregs->csr |= CSR_DMA_ENABLE; |
| #endif |
| sun3_dma_active = 1; |
| #endif |
| |
| if (hostdata->flags & FLAG_LATE_DMA_SETUP) { |
| /* On the Falcon, the DMA setup must be done after the last |
| * NCR access, else the DMA setup gets trashed! |
| */ |
| if (p & SR_IO) |
| result = NCR5380_dma_recv_setup(hostdata, d, c); |
| else |
| result = NCR5380_dma_send_setup(hostdata, d, c); |
| } |
| |
| /* On failure, NCR5380_dma_xxxx_setup() returns a negative int. */ |
| if (result < 0) |
| return result; |
| |
| /* For real DMA, result is the byte count. DMA interrupt is expected. */ |
| if (result > 0) { |
| hostdata->dma_len = result; |
| return 0; |
| } |
| |
| /* The result is zero iff pseudo DMA send/receive was completed. */ |
| hostdata->dma_len = c; |
| |
| /* |
| * 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 |
| * seems to be no terribly good way of doing this on a 5380 under all |
| * conditions. For non-scatter-gather operations, we can wait until REQ |
| * and ACK both go false, or until a phase mismatch occurs. Gather-sends |
| * are nastier, since the device will be expecting more data than we |
| * are prepared to send it, and REQ will remain asserted. On a 53C8[01] we |
| * could test Last Byte Sent to assure transfer (I imagine this is precisely |
| * why this signal was added to the newer chips) but on the older 538[01] |
| * this signal does not exist. The workaround for this lack is a watchdog; |
| * we bail out of the wait-loop after a modest amount of wait-time if |
| * the usual exit conditions are not met. Not a terribly clean or |
| * correct solution :-% |
| * |
| * DMA receive is equally tricky due to a nasty characteristic of the NCR5380. |
| * If the chip is in DMA receive mode, it will respond to a target's |
| * REQ by latching the SCSI data into the INPUT DATA register and asserting |
| * ACK, even if it has _already_ been notified by the DMA controller that |
| * the current DMA transfer has completed! If the NCR5380 is then taken |
| * out of DMA mode, this already-acknowledged byte is lost. This is |
| * not a problem for "one DMA transfer per READ command", because |
| * the situation will never arise... either all of the data is DMA'ed |
| * 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 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 (hostdata->flags & FLAG_DMA_FIXUP) { |
| if (p & SR_IO) { |
| /* |
| * 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. |
| * |
| * After REQ is asserted, the NCR5380 asserts DRQ and ACK. |
| * REQ is deasserted when ACK is asserted, and not reasserted |
| * until ACK goes false. Since the NCR5380 won't lower ACK |
| * until DACK is asserted, which won't happen unless we twiddle |
| * the DMA port or we take the NCR5380 out of DMA mode, we |
| * can guarantee that we won't handshake another extra |
| * byte. |
| */ |
| |
| if (NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, |
| BASR_DRQ, BASR_DRQ, HZ) < 0) { |
| result = -1; |
| shost_printk(KERN_ERR, instance, "PDMA read: DRQ timeout\n"); |
| } |
| if (NCR5380_poll_politely(hostdata, STATUS_REG, |
| SR_REQ, 0, HZ) < 0) { |
| result = -1; |
| shost_printk(KERN_ERR, instance, "PDMA read: !REQ timeout\n"); |
| } |
| d[*count - 1] = NCR5380_read(INPUT_DATA_REG); |
| } else { |
| /* |
| * Wait for the last byte to be sent. If REQ is being asserted for |
| * the byte we're interested, we'll ACK it and it will go false. |
| */ |
| if (NCR5380_poll_politely2(hostdata, |
| BUS_AND_STATUS_REG, BASR_DRQ, BASR_DRQ, |
| BUS_AND_STATUS_REG, BASR_PHASE_MATCH, 0, HZ) < 0) { |
| result = -1; |
| shost_printk(KERN_ERR, instance, "PDMA write: DRQ and phase timeout\n"); |
| } |
| } |
| } |
| |
| NCR5380_dma_complete(instance); |
| return result; |
| } |
| |
| /* |
| * Function : NCR5380_information_transfer (struct Scsi_Host *instance) |
| * |
| * Purpose : run through the various SCSI phases and do as the target |
| * directs us to. Operates on the currently connected command, |
| * instance->connected. |
| * |
| * Inputs : instance, instance for which we are doing commands |
| * |
| * Side effects : SCSI things happen, the disconnected queue will be |
| * modified if a command disconnects, *instance->connected will |
| * change. |
| * |
| * XXX Note : we need to watch for bus free or a reset condition here |
| * to recover from an unexpected bus free condition. |
| */ |
| |
| static void NCR5380_information_transfer(struct Scsi_Host *instance) |
| __releases(&hostdata->lock) __acquires(&hostdata->lock) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| unsigned char msgout = NOP; |
| int sink = 0; |
| int len; |
| int transfersize; |
| unsigned char *data; |
| unsigned char phase, tmp, extended_msg[10], old_phase = 0xff; |
| struct scsi_cmnd *cmd; |
| |
| #ifdef SUN3_SCSI_VME |
| dregs->csr |= CSR_INTR; |
| #endif |
| |
| while ((cmd = hostdata->connected)) { |
| struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd); |
| |
| tmp = NCR5380_read(STATUS_REG); |
| /* We only have a valid SCSI phase when REQ is asserted */ |
| if (tmp & SR_REQ) { |
| phase = (tmp & PHASE_MASK); |
| if (phase != old_phase) { |
| old_phase = phase; |
| NCR5380_dprint_phase(NDEBUG_INFORMATION, instance); |
| } |
| #ifdef CONFIG_SUN3 |
| if (phase == PHASE_CMDOUT && |
| sun3_dma_setup_done != cmd) { |
| int count; |
| |
| advance_sg_buffer(cmd); |
| |
| count = sun3scsi_dma_xfer_len(hostdata, cmd); |
| |
| if (count > 0) { |
| if (rq_data_dir(cmd->request)) |
| sun3scsi_dma_send_setup(hostdata, |
| cmd->SCp.ptr, count); |
| else |
| sun3scsi_dma_recv_setup(hostdata, |
| cmd->SCp.ptr, count); |
| sun3_dma_setup_done = cmd; |
| } |
| #ifdef SUN3_SCSI_VME |
| dregs->csr |= CSR_INTR; |
| #endif |
| } |
| #endif /* CONFIG_SUN3 */ |
| |
| if (sink && (phase != PHASE_MSGOUT)) { |
| NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); |
| |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | |
| ICR_ASSERT_ACK); |
| while (NCR5380_read(STATUS_REG) & SR_REQ) |
| ; |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | |
| ICR_ASSERT_ATN); |
| sink = 0; |
| continue; |
| } |
| |
| switch (phase) { |
| case PHASE_DATAOUT: |
| #if (NDEBUG & NDEBUG_NO_DATAOUT) |
| shost_printk(KERN_DEBUG, instance, "NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n"); |
| sink = 1; |
| do_abort(instance); |
| cmd->result = DID_ERROR << 16; |
| complete_cmd(instance, cmd); |
| hostdata->connected = NULL; |
| hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun); |
| return; |
| #endif |
| case PHASE_DATAIN: |
| /* |
| * If there is no room left in the current buffer in the |
| * scatter-gather list, move onto the next one. |
| */ |
| |
| advance_sg_buffer(cmd); |
| dsprintk(NDEBUG_INFORMATION, instance, |
| "this residual %d, sg ents %d\n", |
| cmd->SCp.this_residual, |
| sg_nents(cmd->SCp.buffer)); |
| |
| /* |
| * The preferred transfer method is going to be |
| * PSEUDO-DMA for systems that are strictly PIO, |
| * since we can let the hardware do the handshaking. |
| * |
| * For this to work, we need to know the transfersize |
| * ahead of time, since the pseudo-DMA code will sit |
| * in an unconditional loop. |
| */ |
| |
| transfersize = 0; |
| if (!cmd->device->borken) |
| transfersize = NCR5380_dma_xfer_len(hostdata, cmd); |
| |
| if (transfersize > 0) { |
| len = transfersize; |
| if (NCR5380_transfer_dma(instance, &phase, |
| &len, (unsigned char **)&cmd->SCp.ptr)) { |
| /* |
| * If the watchdog timer fires, all future |
| * accesses to this device will use the |
| * polled-IO. |
| */ |
| scmd_printk(KERN_INFO, cmd, |
| "switching to slow handshake\n"); |
| cmd->device->borken = 1; |
| do_reset(instance); |
| bus_reset_cleanup(instance); |
| } |
| } else { |
| /* Transfer a small chunk so that the |
| * irq mode lock is not held too long. |
| */ |
| transfersize = min(cmd->SCp.this_residual, |
| NCR5380_PIO_CHUNK_SIZE); |
| len = transfersize; |
| NCR5380_transfer_pio(instance, &phase, &len, |
| (unsigned char **)&cmd->SCp.ptr); |
| cmd->SCp.this_residual -= transfersize - len; |
| } |
| #ifdef CONFIG_SUN3 |
| if (sun3_dma_setup_done == cmd) |
| sun3_dma_setup_done = NULL; |
| #endif |
| return; |
| case PHASE_MSGIN: |
| len = 1; |
| data = &tmp; |
| NCR5380_transfer_pio(instance, &phase, &len, &data); |
| cmd->SCp.Message = tmp; |
| |
| switch (tmp) { |
| case ABORT: |
| case COMMAND_COMPLETE: |
| /* Accept message by clearing ACK */ |
| sink = 1; |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| dsprintk(NDEBUG_QUEUES, instance, |
| "COMMAND COMPLETE %p target %d lun %llu\n", |
| cmd, scmd_id(cmd), cmd->device->lun); |
| |
| hostdata->connected = NULL; |
| hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun); |
| |
| cmd->result &= ~0xffff; |
| cmd->result |= cmd->SCp.Status; |
| cmd->result |= cmd->SCp.Message << 8; |
| |
| set_resid_from_SCp(cmd); |
| |
| if (cmd->cmnd[0] == REQUEST_SENSE) |
| complete_cmd(instance, cmd); |
| else { |
| if (cmd->SCp.Status == SAM_STAT_CHECK_CONDITION || |
| cmd->SCp.Status == SAM_STAT_COMMAND_TERMINATED) { |
| dsprintk(NDEBUG_QUEUES, instance, "autosense: adding cmd %p to tail of autosense queue\n", |
| cmd); |
| list_add_tail(&ncmd->list, |
| &hostdata->autosense); |
| } else |
| complete_cmd(instance, cmd); |
| } |
| |
| /* |
| * Restore phase bits to 0 so an interrupted selection, |
| * arbitration can resume. |
| */ |
| NCR5380_write(TARGET_COMMAND_REG, 0); |
| |
| maybe_release_dma_irq(instance); |
| return; |
| case MESSAGE_REJECT: |
| /* Accept message by clearing ACK */ |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| switch (hostdata->last_message) { |
| case HEAD_OF_QUEUE_TAG: |
| case ORDERED_QUEUE_TAG: |
| case SIMPLE_QUEUE_TAG: |
| cmd->device->simple_tags = 0; |
| hostdata->busy[cmd->device->id] |= (1 << (cmd->device->lun & 0xFF)); |
| break; |
| default: |
| break; |
| } |
| break; |
| case DISCONNECT: |
| /* Accept message by clearing ACK */ |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| hostdata->connected = NULL; |
| list_add(&ncmd->list, &hostdata->disconnected); |
| dsprintk(NDEBUG_INFORMATION | NDEBUG_QUEUES, |
| instance, "connected command %p for target %d lun %llu moved to disconnected queue\n", |
| cmd, scmd_id(cmd), cmd->device->lun); |
| |
| /* |
| * Restore phase bits to 0 so an interrupted selection, |
| * arbitration can resume. |
| */ |
| NCR5380_write(TARGET_COMMAND_REG, 0); |
| |
| #ifdef SUN3_SCSI_VME |
| dregs->csr |= CSR_DMA_ENABLE; |
| #endif |
| return; |
| /* |
| * The SCSI data pointer is *IMPLICITLY* saved on a disconnect |
| * operation, in violation of the SCSI spec so we can safely |
| * ignore SAVE/RESTORE pointers calls. |
| * |
| * Unfortunately, some disks violate the SCSI spec and |
| * don't issue the required SAVE_POINTERS message before |
| * disconnecting, and we have to break spec to remain |
| * compatible. |
| */ |
| case SAVE_POINTERS: |
| case RESTORE_POINTERS: |
| /* Accept message by clearing ACK */ |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| break; |
| case EXTENDED_MESSAGE: |
| /* |
| * Start the message buffer with the EXTENDED_MESSAGE |
| * byte, since spi_print_msg() wants the whole thing. |
| */ |
| extended_msg[0] = EXTENDED_MESSAGE; |
| /* Accept first byte by clearing ACK */ |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| |
| spin_unlock_irq(&hostdata->lock); |
| |
| dsprintk(NDEBUG_EXTENDED, instance, "receiving extended message\n"); |
| |
| len = 2; |
| data = extended_msg + 1; |
| phase = PHASE_MSGIN; |
| NCR5380_transfer_pio(instance, &phase, &len, &data); |
| dsprintk(NDEBUG_EXTENDED, instance, "length %d, code 0x%02x\n", |
| (int)extended_msg[1], |
| (int)extended_msg[2]); |
| |
| if (!len && extended_msg[1] > 0 && |
| extended_msg[1] <= sizeof(extended_msg) - 2) { |
| /* Accept third byte by clearing ACK */ |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| len = extended_msg[1] - 1; |
| data = extended_msg + 3; |
| phase = PHASE_MSGIN; |
| |
| NCR5380_transfer_pio(instance, &phase, &len, &data); |
| dsprintk(NDEBUG_EXTENDED, instance, "message received, residual %d\n", |
| len); |
| |
| switch (extended_msg[2]) { |
| case EXTENDED_SDTR: |
| case EXTENDED_WDTR: |
| tmp = 0; |
| } |
| } else if (len) { |
| shost_printk(KERN_ERR, instance, "error receiving extended message\n"); |
| tmp = 0; |
| } else { |
| shost_printk(KERN_NOTICE, instance, "extended message code %02x length %d is too long\n", |
| extended_msg[2], extended_msg[1]); |
| tmp = 0; |
| } |
| |
| spin_lock_irq(&hostdata->lock); |
| if (!hostdata->connected) |
| return; |
| |
| /* Reject message */ |
| /* Fall through */ |
| default: |
| /* |
| * If we get something weird that we aren't expecting, |
| * log it. |
| */ |
| if (tmp == EXTENDED_MESSAGE) |
| scmd_printk(KERN_INFO, cmd, |
| "rejecting unknown extended message code %02x, length %d\n", |
| extended_msg[2], extended_msg[1]); |
| else if (tmp) |
| scmd_printk(KERN_INFO, cmd, |
| "rejecting unknown message code %02x\n", |
| tmp); |
| |
| msgout = MESSAGE_REJECT; |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); |
| break; |
| } /* switch (tmp) */ |
| break; |
| case PHASE_MSGOUT: |
| len = 1; |
| data = &msgout; |
| hostdata->last_message = msgout; |
| NCR5380_transfer_pio(instance, &phase, &len, &data); |
| if (msgout == ABORT) { |
| hostdata->connected = NULL; |
| hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun); |
| cmd->result = DID_ERROR << 16; |
| complete_cmd(instance, cmd); |
| maybe_release_dma_irq(instance); |
| return; |
| } |
| msgout = NOP; |
| break; |
| case PHASE_CMDOUT: |
| len = cmd->cmd_len; |
| data = cmd->cmnd; |
| /* |
| * XXX for performance reasons, on machines with a |
| * PSEUDO-DMA architecture we should probably |
| * use the dma transfer function. |
| */ |
| NCR5380_transfer_pio(instance, &phase, &len, &data); |
| break; |
| case PHASE_STATIN: |
| len = 1; |
| data = &tmp; |
| NCR5380_transfer_pio(instance, &phase, &len, &data); |
| cmd->SCp.Status = tmp; |
| break; |
| default: |
| shost_printk(KERN_ERR, instance, "unknown phase\n"); |
| NCR5380_dprint(NDEBUG_ANY, instance); |
| } /* switch(phase) */ |
| } else { |
| spin_unlock_irq(&hostdata->lock); |
| NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ); |
| spin_lock_irq(&hostdata->lock); |
| } |
| } |
| } |
| |
| /* |
| * Function : void NCR5380_reselect (struct Scsi_Host *instance) |
| * |
| * Purpose : does reselection, initializing the instance->connected |
| * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q |
| * nexus has been reestablished, |
| * |
| * Inputs : instance - this instance of the NCR5380. |
| */ |
| |
| static void NCR5380_reselect(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| unsigned char target_mask; |
| unsigned char lun; |
| unsigned char msg[3]; |
| struct NCR5380_cmd *ncmd; |
| struct scsi_cmnd *tmp; |
| |
| /* |
| * Disable arbitration, etc. since the host adapter obviously |
| * lost, and tell an interrupted NCR5380_select() to restart. |
| */ |
| |
| NCR5380_write(MODE_REG, MR_BASE); |
| |
| target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask); |
| if (!target_mask || target_mask & (target_mask - 1)) { |
| shost_printk(KERN_WARNING, instance, |
| "reselect: bad target_mask 0x%02x\n", target_mask); |
| return; |
| } |
| |
| /* |
| * At this point, we have detected that our SCSI ID is on the bus, |
| * SEL is true and BSY was false for at least one bus settle delay |
| * (400 ns). |
| * |
| * We must assert BSY ourselves, until the target drops the SEL |
| * signal. |
| */ |
| |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY); |
| if (NCR5380_poll_politely(hostdata, |
| STATUS_REG, SR_SEL, 0, 2 * HZ) < 0) { |
| shost_printk(KERN_ERR, instance, "reselect: !SEL timeout\n"); |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| return; |
| } |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| |
| /* |
| * Wait for target to go into MSGIN. |
| */ |
| |
| if (NCR5380_poll_politely(hostdata, |
| STATUS_REG, SR_REQ, SR_REQ, 2 * HZ) < 0) { |
| if ((NCR5380_read(STATUS_REG) & (SR_BSY | SR_SEL)) == 0) |
| /* BUS FREE phase */ |
| return; |
| shost_printk(KERN_ERR, instance, "reselect: REQ timeout\n"); |
| do_abort(instance); |
| return; |
| } |
| |
| #ifdef CONFIG_SUN3 |
| /* acknowledge toggle to MSGIN */ |
| NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN)); |
| |
| /* peek at the byte without really hitting the bus */ |
| msg[0] = NCR5380_read(CURRENT_SCSI_DATA_REG); |
| #else |
| { |
| int len = 1; |
| unsigned char *data = msg; |
| unsigned char phase = PHASE_MSGIN; |
| |
| NCR5380_transfer_pio(instance, &phase, &len, &data); |
| |
| if (len) { |
| do_abort(instance); |
| return; |
| } |
| } |
| #endif /* CONFIG_SUN3 */ |
| |
| if (!(msg[0] & 0x80)) { |
| shost_printk(KERN_ERR, instance, "expecting IDENTIFY message, got "); |
| spi_print_msg(msg); |
| printk("\n"); |
| do_abort(instance); |
| return; |
| } |
| lun = msg[0] & 0x07; |
| |
| /* |
| * We need to add code for SCSI-II to track which devices have |
| * I_T_L_Q nexuses established, and which have simple I_T_L |
| * nexuses so we can chose to do additional data transfer. |
| */ |
| |
| /* |
| * Find the command corresponding to the I_T_L or I_T_L_Q nexus we |
| * just reestablished, and remove it from the disconnected queue. |
| */ |
| |
| tmp = NULL; |
| list_for_each_entry(ncmd, &hostdata->disconnected, list) { |
| struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd); |
| |
| if (target_mask == (1 << scmd_id(cmd)) && |
| lun == (u8)cmd->device->lun) { |
| list_del(&ncmd->list); |
| tmp = cmd; |
| break; |
| } |
| } |
| |
| if (tmp) { |
| dsprintk(NDEBUG_RESELECTION | NDEBUG_QUEUES, instance, |
| "reselect: removed %p from disconnected queue\n", tmp); |
| } else { |
| int target = ffs(target_mask) - 1; |
| |
| shost_printk(KERN_ERR, instance, "target bitmask 0x%02x lun %d not in disconnected queue.\n", |
| target_mask, lun); |
| /* |
| * Since we have an established nexus that we can't do anything |
| * with, we must abort it. |
| */ |
| if (do_abort(instance) == 0) |
| hostdata->busy[target] &= ~(1 << lun); |
| return; |
| } |
| |
| #ifdef CONFIG_SUN3 |
| if (sun3_dma_setup_done != tmp) { |
| int count; |
| |
| advance_sg_buffer(tmp); |
| |
| count = sun3scsi_dma_xfer_len(hostdata, tmp); |
| |
| if (count > 0) { |
| if (rq_data_dir(tmp->request)) |
| sun3scsi_dma_send_setup(hostdata, |
| tmp->SCp.ptr, count); |
| else |
| sun3scsi_dma_recv_setup(hostdata, |
| tmp->SCp.ptr, count); |
| sun3_dma_setup_done = tmp; |
| } |
| } |
| |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); |
| #endif /* CONFIG_SUN3 */ |
| |
| /* Accept message by clearing ACK */ |
| NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); |
| |
| hostdata->connected = tmp; |
| dsprintk(NDEBUG_RESELECTION, instance, "nexus established, target %d, lun %llu\n", |
| scmd_id(tmp), tmp->device->lun); |
| } |
| |
| /** |
| * list_find_cmd - test for presence of a command in a linked list |
| * @haystack: list of commands |
| * @needle: command to search for |
| */ |
| |
| static bool list_find_cmd(struct list_head *haystack, |
| struct scsi_cmnd *needle) |
| { |
| struct NCR5380_cmd *ncmd; |
| |
| list_for_each_entry(ncmd, haystack, list) |
| if (NCR5380_to_scmd(ncmd) == needle) |
| return true; |
| return false; |
| } |
| |
| /** |
| * list_remove_cmd - remove a command from linked list |
| * @haystack: list of commands |
| * @needle: command to remove |
| */ |
| |
| static bool list_del_cmd(struct list_head *haystack, |
| struct scsi_cmnd *needle) |
| { |
| if (list_find_cmd(haystack, needle)) { |
| struct NCR5380_cmd *ncmd = scsi_cmd_priv(needle); |
| |
| list_del(&ncmd->list); |
| return true; |
| } |
| return false; |
| } |
| |
| /** |
| * NCR5380_abort - scsi host eh_abort_handler() method |
| * @cmd: the command to be aborted |
| * |
| * Try to abort a given command by removing it from queues and/or sending |
| * the target an abort message. This may not succeed in causing a target |
| * to abort the command. Nonetheless, the low-level driver must forget about |
| * the command because the mid-layer reclaims it and it may be re-issued. |
| * |
| * The normal path taken by a command is as follows. For EH we trace this |
| * same path to locate and abort the command. |
| * |
| * unissued -> selecting -> [unissued -> selecting ->]... connected -> |
| * [disconnected -> connected ->]... |
| * [autosense -> connected ->] done |
| * |
| * If cmd was not found at all then presumably it has already been completed, |
| * in which case return SUCCESS to try to avoid further EH measures. |
| * |
| * If the command has not completed yet, we must not fail to find it. |
| * We have no option but to forget the aborted command (even if it still |
| * lacks sense data). The mid-layer may re-issue a command that is in error |
| * recovery (see scsi_send_eh_cmnd), but the logic and data structures in |
| * this driver are such that a command can appear on one queue only. |
| * |
| * The lock protects driver data structures, but EH handlers also use it |
| * to serialize their own execution and prevent their own re-entry. |
| */ |
| |
| static int NCR5380_abort(struct scsi_cmnd *cmd) |
| { |
| struct Scsi_Host *instance = cmd->device->host; |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| unsigned long flags; |
| int result = SUCCESS; |
| |
| spin_lock_irqsave(&hostdata->lock, flags); |
| |
| #if (NDEBUG & NDEBUG_ANY) |
| scmd_printk(KERN_INFO, cmd, __func__); |
| #endif |
| NCR5380_dprint(NDEBUG_ANY, instance); |
| NCR5380_dprint_phase(NDEBUG_ANY, instance); |
| |
| if (list_del_cmd(&hostdata->unissued, cmd)) { |
| dsprintk(NDEBUG_ABORT, instance, |
| "abort: removed %p from issue queue\n", cmd); |
| cmd->result = DID_ABORT << 16; |
| cmd->scsi_done(cmd); /* No tag or busy flag to worry about */ |
| goto out; |
| } |
| |
| if (hostdata->selecting == cmd) { |
| dsprintk(NDEBUG_ABORT, instance, |
| "abort: cmd %p == selecting\n", cmd); |
| hostdata->selecting = NULL; |
| cmd->result = DID_ABORT << 16; |
| complete_cmd(instance, cmd); |
| goto out; |
| } |
| |
| if (list_del_cmd(&hostdata->disconnected, cmd)) { |
| dsprintk(NDEBUG_ABORT, instance, |
| "abort: removed %p from disconnected list\n", cmd); |
| /* Can't call NCR5380_select() and send ABORT because that |
| * means releasing the lock. Need a bus reset. |
| */ |
| set_host_byte(cmd, DID_ERROR); |
| complete_cmd(instance, cmd); |
| result = FAILED; |
| goto out; |
| } |
| |
| if (hostdata->connected == cmd) { |
| dsprintk(NDEBUG_ABORT, instance, "abort: cmd %p is connected\n", cmd); |
| hostdata->connected = NULL; |
| hostdata->dma_len = 0; |
| if (do_abort(instance) < 0) { |
| set_host_byte(cmd, DID_ERROR); |
| complete_cmd(instance, cmd); |
| result = FAILED; |
| goto out; |
| } |
| set_host_byte(cmd, DID_ABORT); |
| complete_cmd(instance, cmd); |
| goto out; |
| } |
| |
| if (list_del_cmd(&hostdata->autosense, cmd)) { |
| dsprintk(NDEBUG_ABORT, instance, |
| "abort: removed %p from sense queue\n", cmd); |
| complete_cmd(instance, cmd); |
| } |
| |
| out: |
| if (result == FAILED) |
| dsprintk(NDEBUG_ABORT, instance, "abort: failed to abort %p\n", cmd); |
| else { |
| hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun); |
| dsprintk(NDEBUG_ABORT, instance, "abort: successfully aborted %p\n", cmd); |
| } |
| |
| queue_work(hostdata->work_q, &hostdata->main_task); |
| maybe_release_dma_irq(instance); |
| spin_unlock_irqrestore(&hostdata->lock, flags); |
| |
| return result; |
| } |
| |
| |
| static void bus_reset_cleanup(struct Scsi_Host *instance) |
| { |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| int i; |
| struct NCR5380_cmd *ncmd; |
| |
| /* reset NCR registers */ |
| NCR5380_write(MODE_REG, MR_BASE); |
| NCR5380_write(TARGET_COMMAND_REG, 0); |
| NCR5380_write(SELECT_ENABLE_REG, 0); |
| |
| /* After the reset, there are no more connected or disconnected commands |
| * and no busy units; so clear the low-level status here to avoid |
| * conflicts when the mid-level code tries to wake up the affected |
| * commands! |
| */ |
| |
| if (hostdata->selecting) { |
| hostdata->selecting->result = DID_RESET << 16; |
| complete_cmd(instance, hostdata->selecting); |
| hostdata->selecting = NULL; |
| } |
| |
| list_for_each_entry(ncmd, &hostdata->disconnected, list) { |
| struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd); |
| |
| set_host_byte(cmd, DID_RESET); |
| complete_cmd(instance, cmd); |
| } |
| INIT_LIST_HEAD(&hostdata->disconnected); |
| |
| list_for_each_entry(ncmd, &hostdata->autosense, list) { |
| struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd); |
| |
| cmd->scsi_done(cmd); |
| } |
| INIT_LIST_HEAD(&hostdata->autosense); |
| |
| if (hostdata->connected) { |
| set_host_byte(hostdata->connected, DID_RESET); |
| complete_cmd(instance, hostdata->connected); |
| hostdata->connected = NULL; |
| } |
| |
| for (i = 0; i < 8; ++i) |
| hostdata->busy[i] = 0; |
| hostdata->dma_len = 0; |
| |
| queue_work(hostdata->work_q, &hostdata->main_task); |
| maybe_release_dma_irq(instance); |
| } |
| |
| /** |
| * NCR5380_host_reset - reset the SCSI host |
| * @cmd: SCSI command undergoing EH |
| * |
| * Returns SUCCESS |
| */ |
| |
| static int NCR5380_host_reset(struct scsi_cmnd *cmd) |
| { |
| struct Scsi_Host *instance = cmd->device->host; |
| struct NCR5380_hostdata *hostdata = shost_priv(instance); |
| unsigned long flags; |
| struct NCR5380_cmd *ncmd; |
| |
| spin_lock_irqsave(&hostdata->lock, flags); |
| |
| #if (NDEBUG & NDEBUG_ANY) |
| shost_printk(KERN_INFO, instance, __func__); |
| #endif |
| NCR5380_dprint(NDEBUG_ANY, instance); |
| NCR5380_dprint_phase(NDEBUG_ANY, instance); |
| |
| list_for_each_entry(ncmd, &hostdata->unissued, list) { |
| struct scsi_cmnd *scmd = NCR5380_to_scmd(ncmd); |
| |
| scmd->result = DID_RESET << 16; |
| scmd->scsi_done(scmd); |
| } |
| INIT_LIST_HEAD(&hostdata->unissued); |
| |
| do_reset(instance); |
| bus_reset_cleanup(instance); |
| |
| spin_unlock_irqrestore(&hostdata->lock, flags); |
| |
| return SUCCESS; |
| } |