+++ /dev/null
-/*
- * 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
- */
-
-/* Ported to Atari by Roman Hodek and others. */
-
-/* Adapted for the sun3 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 control options :
- * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
- * for commands that return with a CHECK CONDITION status.
- *
- * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
- * transceivers.
- *
- * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
- *
- * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
- *
- * 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
- * Note that the DMA setup functions should return the number of bytes
- * that they were able to program the controller for.
- *
- * NCR5380_dma_write_setup(instance, src, count) - initialize
- * NCR5380_dma_read_setup(instance, dst, count) - initialize
- * NCR5380_dma_residual(instance); - residual count
- *
- * PSEUDO functions :
- * NCR5380_pwrite(instance, src, count)
- * NCR5380_pread(instance, dst, count);
- *
- * The generic driver is initialized by calling NCR5380_init(instance),
- * after setting the appropriate host specific fields and ID. If the
- * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
- * possible) function may be used.
- */
-
-static int do_abort(struct Scsi_Host *);
-static void do_reset(struct Scsi_Host *);
-
-#ifdef SUPPORT_TAGS
-
-/*
- * Functions for handling tagged queuing
- * =====================================
- *
- * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
- *
- * Using consecutive numbers for the tags is no good idea in my eyes. There
- * could be wrong re-usings if the counter (8 bit!) wraps and some early
- * command has been preempted for a long time. My solution: a bitfield for
- * remembering used tags.
- *
- * There's also the problem that each target has a certain queue size, but we
- * cannot know it in advance :-( We just see a QUEUE_FULL status being
- * returned. So, in this case, the driver internal queue size assumption is
- * reduced to the number of active tags if QUEUE_FULL is returned by the
- * target.
- *
- * We're also not allowed running tagged commands as long as an untagged
- * command is active. And REQUEST SENSE commands after a contingent allegiance
- * condition _must_ be untagged. To keep track whether an untagged command has
- * been issued, the host->busy array is still employed, as it is without
- * support for tagged queuing.
- *
- * One could suspect that there are possible race conditions between
- * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
- * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
- * which already guaranteed to be running at most once. It is also the only
- * place where tags/LUNs are allocated. So no other allocation can slip
- * between that pair, there could only happen a reselection, which can free a
- * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
- * important: the tag bit must be cleared before 'nr_allocated' is decreased.
- */
-
-static void __init init_tags(struct NCR5380_hostdata *hostdata)
-{
- int target, lun;
- struct tag_alloc *ta;
-
- if (!(hostdata->flags & FLAG_TAGGED_QUEUING))
- return;
-
- for (target = 0; target < 8; ++target) {
- for (lun = 0; lun < 8; ++lun) {
- ta = &hostdata->TagAlloc[target][lun];
- bitmap_zero(ta->allocated, MAX_TAGS);
- ta->nr_allocated = 0;
- /* At the beginning, assume the maximum queue size we could
- * support (MAX_TAGS). This value will be decreased if the target
- * returns QUEUE_FULL status.
- */
- ta->queue_size = MAX_TAGS;
- }
- }
-}
-
-
-/* Check if we can issue a command to this LUN: First see if the LUN is marked
- * busy by an untagged command. If the command should use tagged queuing, also
- * check that there is a free tag and the target's queue won't overflow. This
- * function should be called with interrupts disabled to avoid race
- * conditions.
- */
-
-static int is_lun_busy(struct scsi_cmnd *cmd, int should_be_tagged)
-{
- u8 lun = cmd->device->lun;
- struct Scsi_Host *instance = cmd->device->host;
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
-
- if (hostdata->busy[cmd->device->id] & (1 << lun))
- return 1;
- if (!should_be_tagged ||
- !(hostdata->flags & FLAG_TAGGED_QUEUING) ||
- !cmd->device->tagged_supported)
- return 0;
- if (hostdata->TagAlloc[scmd_id(cmd)][lun].nr_allocated >=
- hostdata->TagAlloc[scmd_id(cmd)][lun].queue_size) {
- dsprintk(NDEBUG_TAGS, instance, "target %d lun %d: no free tags\n",
- scmd_id(cmd), lun);
- return 1;
- }
- return 0;
-}
-
-
-/* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
- * must be called before!), or reserve the LUN in 'busy' if the command is
- * untagged.
- */
-
-static void cmd_get_tag(struct scsi_cmnd *cmd, int should_be_tagged)
-{
- u8 lun = cmd->device->lun;
- struct Scsi_Host *instance = cmd->device->host;
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
-
- /* If we or the target don't support tagged queuing, allocate the LUN for
- * an untagged command.
- */
- if (!should_be_tagged ||
- !(hostdata->flags & FLAG_TAGGED_QUEUING) ||
- !cmd->device->tagged_supported) {
- cmd->tag = TAG_NONE;
- hostdata->busy[cmd->device->id] |= (1 << lun);
- dsprintk(NDEBUG_TAGS, instance, "target %d lun %d now allocated by untagged command\n",
- scmd_id(cmd), lun);
- } else {
- struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun];
-
- cmd->tag = find_first_zero_bit(ta->allocated, MAX_TAGS);
- set_bit(cmd->tag, ta->allocated);
- ta->nr_allocated++;
- dsprintk(NDEBUG_TAGS, instance, "using tag %d for target %d lun %d (%d tags allocated)\n",
- cmd->tag, scmd_id(cmd), lun, ta->nr_allocated);
- }
-}
-
-
-/* Mark the tag of command 'cmd' as free, or in case of an untagged command,
- * unlock the LUN.
- */
-
-static void cmd_free_tag(struct scsi_cmnd *cmd)
-{
- u8 lun = cmd->device->lun;
- struct Scsi_Host *instance = cmd->device->host;
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
-
- if (cmd->tag == TAG_NONE) {
- hostdata->busy[cmd->device->id] &= ~(1 << lun);
- dsprintk(NDEBUG_TAGS, instance, "target %d lun %d untagged cmd freed\n",
- scmd_id(cmd), lun);
- } else if (cmd->tag >= MAX_TAGS) {
- shost_printk(KERN_NOTICE, instance,
- "trying to free bad tag %d!\n", cmd->tag);
- } else {
- struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun];
- clear_bit(cmd->tag, ta->allocated);
- ta->nr_allocated--;
- dsprintk(NDEBUG_TAGS, instance, "freed tag %d for target %d lun %d\n",
- cmd->tag, scmd_id(cmd), lun);
- }
-}
-
-
-static void free_all_tags(struct NCR5380_hostdata *hostdata)
-{
- int target, lun;
- struct tag_alloc *ta;
-
- if (!(hostdata->flags & FLAG_TAGGED_QUEUING))
- return;
-
- for (target = 0; target < 8; ++target) {
- for (lun = 0; lun < 8; ++lun) {
- ta = &hostdata->TagAlloc[target][lun];
- bitmap_zero(ta->allocated, MAX_TAGS);
- ta->nr_allocated = 0;
- }
- }
-}
-
-#endif /* SUPPORT_TAGS */
-
-/**
- * merge_contiguous_buffers - coalesce scatter-gather list entries
- * @cmd: command requesting IO
- *
- * Try to merge several scatter-gather buffers into one DMA transfer.
- * This is possible if the scatter buffers lie on physically
- * contiguous addresses. The first scatter-gather buffer's data are
- * assumed to be already transferred into cmd->SCp.this_residual.
- * Every buffer merged avoids an interrupt and a DMA setup operation.
- */
-
-static void merge_contiguous_buffers(struct scsi_cmnd *cmd)
-{
-#if !defined(CONFIG_SUN3)
- unsigned long endaddr;
-#if (NDEBUG & NDEBUG_MERGING)
- unsigned long oldlen = cmd->SCp.this_residual;
- int cnt = 1;
-#endif
-
- for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
- cmd->SCp.buffers_residual &&
- virt_to_phys(sg_virt(&cmd->SCp.buffer[1])) == endaddr;) {
- dprintk(NDEBUG_MERGING, "VTOP(%p) == %08lx -> merging\n",
- page_address(sg_page(&cmd->SCp.buffer[1])), endaddr);
-#if (NDEBUG & NDEBUG_MERGING)
- ++cnt;
-#endif
- ++cmd->SCp.buffer;
- --cmd->SCp.buffers_residual;
- cmd->SCp.this_residual += cmd->SCp.buffer->length;
- endaddr += cmd->SCp.buffer->length;
- }
-#if (NDEBUG & NDEBUG_MERGING)
- if (oldlen != cmd->SCp.this_residual)
- dprintk(NDEBUG_MERGING, "merged %d buffers from %p, new length %08x\n",
- cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
-#endif
-#endif /* !defined(CONFIG_SUN3) */
-}
-
-/**
- * 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.buffers_residual = scsi_sg_count(cmd) - 1;
- cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
- cmd->SCp.this_residual = cmd->SCp.buffer->length;
-
- merge_contiguous_buffers(cmd);
- } else {
- cmd->SCp.buffer = NULL;
- cmd->SCp.buffers_residual = 0;
- cmd->SCp.ptr = NULL;
- cmd->SCp.this_residual = 0;
- }
-
- cmd->SCp.Status = 0;
- cmd->SCp.Message = 0;
-}
-
-/**
- * NCR5380_poll_politely2 - wait for two chip register values
- * @instance: controller to poll
- * @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 Scsi_Host *instance,
- int reg1, int bit1, int val1,
- int reg2, int bit2, int val2, int wait)
-{
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
- unsigned long deadline = jiffies + wait;
- unsigned long n;
-
- /* Busy-wait for up to 10 ms */
- n = min(10000U, jiffies_to_usecs(wait));
- n *= hostdata->accesses_per_ms;
- n /= 2000;
- 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;
-}
-
-static inline int NCR5380_poll_politely(struct Scsi_Host *instance,
- int reg, int bit, int val, int wait)
-{
- return NCR5380_poll_politely2(instance, reg, bit, val,
- reg, bit, val, wait);
-}
-
-#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_ATN, "ATN"},
- {BASR_ACK, "ACK"},
- {0, NULL}
-},
-icrs[] = {
- {ICR_ASSERT_RST, "ASSERT RST"},
- {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, "MODE BLOCK DMA"},
- {MR_TARGET, "MODE TARGET"},
- {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"},
- {MR_ENABLE_PAR_INTR, "MODE PARITY INTR"},
- {MR_ENABLE_EOP_INTR, "MODE EOP INTR"},
- {MR_MONITOR_BSY, "MODE MONITOR BSY"},
- {MR_DMA_MODE, "MODE DMA"},
- {MR_ARBITRATE, "MODE ARBITRATION"},
- {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)
-{
- unsigned char status, data, basr, mr, icr, i;
-
- data = NCR5380_read(CURRENT_SCSI_DATA_REG);
- status = NCR5380_read(STATUS_REG);
- mr = NCR5380_read(MODE_REG);
- icr = NCR5380_read(INITIATOR_COMMAND_REG);
- basr = NCR5380_read(BUS_AND_STATUS_REG);
-
- printk("STATUS_REG: %02x ", status);
- for (i = 0; signals[i].mask; ++i)
- if (status & signals[i].mask)
- printk(",%s", signals[i].name);
- printk("\nBASR: %02x ", basr);
- for (i = 0; basrs[i].mask; ++i)
- if (basr & basrs[i].mask)
- printk(",%s", basrs[i].name);
- printk("\nICR: %02x ", icr);
- for (i = 0; icrs[i].mask; ++i)
- if (icr & icrs[i].mask)
- printk(",%s", icrs[i].name);
- printk("\nMODE: %02x ", mr);
- for (i = 0; mrs[i].mask; ++i)
- if (mr & mrs[i].mask)
- printk(",%s", mrs[i].name);
- printk("\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)
-{
- 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
-
-/**
- * NCR58380_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;
-}
-
-static void prepare_info(struct Scsi_Host *instance)
-{
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
-
- snprintf(hostdata->info, sizeof(hostdata->info),
- "%s, io_port 0x%lx, n_io_port %d, "
- "base 0x%lx, irq %d, "
- "can_queue %d, cmd_per_lun %d, "
- "sg_tablesize %d, this_id %d, "
- "flags { %s%s}, "
- "options { %s} ",
- instance->hostt->name, instance->io_port, instance->n_io_port,
- instance->base, instance->irq,
- instance->can_queue, instance->cmd_per_lun,
- instance->sg_tablesize, instance->this_id,
- hostdata->flags & FLAG_TAGGED_QUEUING ? "TAGGED_QUEUING " : "",
- hostdata->flags & FLAG_TOSHIBA_DELAY ? "TOSHIBA_DELAY " : "",
-#ifdef DIFFERENTIAL
- "DIFFERENTIAL "
-#endif
-#ifdef PARITY
- "PARITY "
-#endif
-#ifdef SUPPORT_TAGS
- "SUPPORT_TAGS "
-#endif
- "");
-}
-
-/**
- * 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 __init NCR5380_init(struct Scsi_Host *instance, int flags)
-{
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
- int i;
- unsigned long deadline;
-
- 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;
-#ifdef SUPPORT_TAGS
- init_tags(hostdata);
-#endif
- 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;
-
- prepare_info(instance);
-
- 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));
- hostdata->accesses_per_ms = i / 256;
-
- 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(instance,
- 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 ((cmd->result & 0xff) != SAM_STAT_GOOD) {
- scsi_eh_restore_cmnd(cmd, &hostdata->ses);
- set_host_byte(cmd, DID_ERROR);
- } else
- scsi_eh_restore_cmnd(cmd, &hostdata->ses);
- hostdata->sensing = NULL;
- }
-
-#ifdef SUPPORT_TAGS
- cmd_free_tag(cmd);
-#else
- hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
-#endif
- 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;
-
- /*
- * ++roman: Just disabling the NCR interrupt isn't sufficient here,
- * because also a timer int can trigger an abort or reset, which would
- * alter queues and touch the lock.
- */
- 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 (
-#ifdef SUPPORT_TAGS
- !is_lun_busy(cmd, 1)
-#else
- !(hostdata->busy[scmd_id(cmd)] & (1 << cmd->device->lun))
-#endif
- ) {
- 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;
-
- /*
- * ++roman: Just disabling the NCR interrupt isn't sufficient here,
- * because also a timer int can trigger an abort or reset, which can
- * alter queues and touch the Falcon lock.
- */
-
- 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.
- */
- /* ++roman: ...and the standard also requires that
- * REQUEST SENSE command are untagged.
- */
-
-#ifdef SUPPORT_TAGS
- cmd_get_tag(cmd, cmd->cmnd[0] != REQUEST_SENSE);
-#endif
- 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);
-#ifdef SUPPORT_TAGS
- cmd_free_tag(cmd);
-#endif
- }
- }
- if (hostdata->connected && !hostdata->dma_len) {
- dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n");
- NCR5380_information_transfer(instance);
- done = 0;
- }
- spin_unlock_irq(&hostdata->lock);
- if (!done)
- cond_resched();
- } while (!done);
-}
-
-
-/*
- * 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.
- */
-
-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");
- }
- }
- }
-
-#if defined(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();
- }
-
- /* make sure we're not stuck in a data phase */
- 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(instance);
- 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) {
- dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n");
- *(*data)++ = saved_data;
- (*count)--;
- cnt--;
- toPIO--;
- }
- dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*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 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);
-
- dsprintk(NDEBUG_INTR, instance, "unknown interrupt\n");
-#ifdef SUN3_SCSI_VME
- dregs->csr |= CSR_DMA_ENABLE;
-#endif
- }
- handled = 1;
- } else {
- shost_printk(KERN_NOTICE, 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);
-}
-
-/*
- * Function : int NCR5380_select(struct Scsi_Host *instance,
- * struct scsi_cmnd *cmd)
- *
- * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
- * including ARBITRATION, SELECTION, and initial message out for
- * IDENTIFY and queue messages.
- *
- * Inputs : instance - instantiation of the 5380 driver on which this
- * target lives, cmd - SCSI command to execute.
- *
- * Returns cmd if selection failed but should be retried,
- * NULL if selection failed and should not be retried, or
- * NULL if selection succeeded (hostdata->connected == cmd).
- *
- * 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 : I_T_L or I_T_L_Q nexus will be established,
- * instance->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 struct scsi_cmnd *NCR5380_select(struct Scsi_Host *instance,
- struct scsi_cmnd *cmd)
-{
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
- unsigned char tmp[3], phase;
- unsigned char *data;
- int len;
- int err;
-
- 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 NULL
- * 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(instance, 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);
- goto out;
- }
- 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);
- goto out;
- }
-
- 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(instance, 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);
- if (!hostdata->connected)
- NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
- 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);
- NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
- /* Can't touch cmd if it has been reclaimed by the scsi ML */
- if (hostdata->selecting) {
- cmd->result = DID_BAD_TARGET << 16;
- complete_cmd(instance, cmd);
- dsprintk(NDEBUG_SELECTION, instance, "target did not respond within 250ms\n");
- cmd = NULL;
- }
- 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.
- *
- * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
- * message (2 bytes) with a tag ID that we increment with every command
- * until it wraps back to 0.
- *
- * XXX - it turns out that there are some broken SCSI-II devices,
- * which claim to support tagged queuing but fail when more than
- * some number of commands are issued at once.
- */
-
- /* Wait for start of REQ/ACK handshake */
-
- err = NCR5380_poll_politely(instance, 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);
- NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
- goto out;
- }
- if (!hostdata->selecting) {
- do_abort(instance);
- goto out;
- }
-
- dsprintk(NDEBUG_SELECTION, instance, "target %d selected, going into MESSAGE OUT phase.\n",
- scmd_id(cmd));
- tmp[0] = IDENTIFY(1, cmd->device->lun);
-
-#ifdef SUPPORT_TAGS
- if (cmd->tag != TAG_NONE) {
- tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
- tmp[2] = cmd->tag;
- len = 3;
- } else
- len = 1;
-#else
- len = 1;
- cmd->tag = 0;
-#endif /* SUPPORT_TAGS */
-
- /* Send message(s) */
- data = tmp;
- phase = PHASE_MSGOUT;
- NCR5380_transfer_pio(instance, &phase, &len, &data);
- dsprintk(NDEBUG_SELECTION, instance, "nexus established.\n");
- /* XXX need to handle errors here */
-
- hostdata->connected = cmd;
-#ifndef SUPPORT_TAGS
- hostdata->busy[cmd->device->id] |= 1 << cmd->device->lun;
-#endif
-#ifdef SUN3_SCSI_VME
- dregs->csr |= CSR_INTR;
-#endif
-
- initialize_SCp(cmd);
-
- cmd = NULL;
-
-out:
- if (!hostdata->selecting)
- return NULL;
- hostdata->selecting = NULL;
- return cmd;
-}
-
-/*
- * 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)
-{
- 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(instance, 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(instance,
- 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)
-{
- 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, -1 on failure.
- */
-
-static int do_abort(struct Scsi_Host *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(instance, STATUS_REG, SR_REQ, SR_REQ, 10 * HZ);
- if (rc < 0)
- goto timeout;
-
- 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(instance, STATUS_REG, SR_REQ, 0, 3 * HZ);
- if (rc < 0)
- goto timeout;
- 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 we got here, and the command completed successfully,
- * we're about to go into bus free state.
- */
-
- return len ? -1 : 0;
-
-timeout:
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
- return -1;
-}
-
-
-/*
- * 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);
- register int c = *count;
- register unsigned char p = *phase;
-
-#if defined(CONFIG_SUN3)
- /* sanity check */
- if (!sun3_dma_setup_done) {
- pr_err("scsi%d: transfer_dma without setup!\n",
- instance->host_no);
- BUG();
- }
- hostdata->dma_len = c;
-
- dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n",
- (p & SR_IO) ? "receive" : "send", c, *data);
-
- /* netbsd turns off ints here, why not be safe and do it too */
-
- /* send start chain */
- sun3scsi_dma_start(c, *data);
-
- 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 (p & SR_IO) {
- NCR5380_write(INITIATOR_COMMAND_REG, 0);
- NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
- } else {
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_DATA);
- NCR5380_write(START_DMA_SEND_REG, 0);
- }
-
-#ifdef SUN3_SCSI_VME
- dregs->csr |= CSR_DMA_ENABLE;
-#endif
-
- sun3_dma_active = 1;
-
-#else /* !defined(CONFIG_SUN3) */
- register unsigned char *d = *data;
- unsigned char tmp;
-
- if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
- *phase = tmp;
- return -1;
- }
-
- if (hostdata->read_overruns && (p & SR_IO))
- c -= hostdata->read_overruns;
-
- dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n",
- (p & SR_IO) ? "receive" : "send", c, d);
-
- 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.
- */
- hostdata->dma_len = (p & SR_IO) ?
- NCR5380_dma_read_setup(instance, d, c) :
- NCR5380_dma_write_setup(instance, d, c);
- }
-
- if (p & SR_IO)
- NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
- else {
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
- NCR5380_write(START_DMA_SEND_REG, 0);
- }
-
- 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!
- */
- hostdata->dma_len = (p & SR_IO) ?
- NCR5380_dma_read_setup(instance, d, c) :
- NCR5380_dma_write_setup(instance, d, c);
- }
-#endif /* !defined(CONFIG_SUN3) */
-
- return 0;
-}
-
-/*
- * 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)
-{
- 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);
- }
-#if defined(CONFIG_SUN3)
- if (phase == PHASE_CMDOUT) {
- void *d;
- unsigned long count;
-
- if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
- count = cmd->SCp.buffer->length;
- d = sg_virt(cmd->SCp.buffer);
- } else {
- count = cmd->SCp.this_residual;
- d = cmd->SCp.ptr;
- }
- /* this command setup for dma yet? */
- if (sun3_dma_setup_done != cmd &&
- sun3scsi_dma_xfer_len(count, cmd) > 0) {
- sun3scsi_dma_setup(instance, d, count,
- rq_data_dir(cmd->request));
- 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;
- 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.
- */
-
- if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
- ++cmd->SCp.buffer;
- --cmd->SCp.buffers_residual;
- cmd->SCp.this_residual = cmd->SCp.buffer->length;
- cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
- merge_contiguous_buffers(cmd);
- dsprintk(NDEBUG_INFORMATION, instance, "%d bytes and %d buffers left\n",
- cmd->SCp.this_residual,
- cmd->SCp.buffers_residual);
- }
-
- /*
- * 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.
- */
-
-#if !defined(CONFIG_SUN3)
- transfersize = 0;
- if (!cmd->device->borken)
-#endif
- transfersize = NCR5380_dma_xfer_len(instance, cmd, phase);
-
- if (transfersize > 0) {
- len = transfersize;
- cmd->SCp.phase = phase;
- 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;
- sink = 1;
- do_abort(instance);
- cmd->result = DID_ERROR << 16;
- /* XXX - need to source or sink data here, as appropriate */
- } else
- return;
- } else {
- /* Break up transfer into 3 ms chunks,
- * presuming 6 accesses per handshake.
- */
- transfersize = min((unsigned long)cmd->SCp.this_residual,
- hostdata->accesses_per_ms / 2);
- len = transfersize;
- NCR5380_transfer_pio(instance, &phase, &len,
- (unsigned char **)&cmd->SCp.ptr);
- cmd->SCp.this_residual -= transfersize - len;
- }
-#if defined(CONFIG_SUN3)
- /* if we had intended to dma that command clear it */
- 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 */
- 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;
-#ifdef SUPPORT_TAGS
- cmd_free_tag(cmd);
- if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
- u8 lun = cmd->device->lun;
- struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun];
-
- dsprintk(NDEBUG_TAGS, instance,
- "QUEUE_FULL %p target %d lun %d nr_allocated %d\n",
- cmd, scmd_id(cmd), lun, ta->nr_allocated);
- if (ta->queue_size > ta->nr_allocated)
- ta->queue_size = ta->nr_allocated;
- }
-#endif
-
- cmd->result &= ~0xffff;
- cmd->result |= cmd->SCp.Status;
- cmd->result |= cmd->SCp.Message << 8;
-
- 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);
-
- /* Enable reselect interrupts */
- NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
-
- 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:
- /* The target obviously doesn't support tagged
- * queuing, even though it announced this ability in
- * its INQUIRY data ?!? (maybe only this LUN?) Ok,
- * clear 'tagged_supported' and lock the LUN, since
- * the command is treated as untagged further on.
- */
- cmd->device->tagged_supported = 0;
- hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
- cmd->tag = TAG_NONE;
- dsprintk(NDEBUG_TAGS, instance, "target %d lun %llu rejected QUEUE_TAG message; tagged queuing disabled\n",
- scmd_id(cmd), cmd->device->lun);
- 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);
-
- /* Enable reselect interrupts */
- NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
-#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:
- case EXTENDED_MODIFY_DATA_POINTER:
- case EXTENDED_EXTENDED_IDENTIFY:
- 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;
-
- /* Fall through to reject message */
-
- /*
- * If we get something weird that we aren't expecting,
- * reject it.
- */
- default:
- if (!tmp) {
- shost_printk(KERN_ERR, instance, "rejecting message ");
- spi_print_msg(extended_msg);
- printk("\n");
- } else if (tmp != EXTENDED_MESSAGE)
- scmd_printk(KERN_INFO, cmd,
- "rejecting unknown message %02x\n",
- tmp);
- else
- scmd_printk(KERN_INFO, cmd,
- "rejecting unknown extended message code %02x, length %d\n",
- extended_msg[1], extended_msg[0]);
-
- 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;
- cmd->result = DID_ERROR << 16;
- complete_cmd(instance, cmd);
- maybe_release_dma_irq(instance);
- NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
- 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(instance, 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.
- */
-
-
-/* it might eventually prove necessary to do a dma setup on
- reselection, but it doesn't seem to be needed now -- sam */
-
-static void NCR5380_reselect(struct Scsi_Host *instance)
-{
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
- unsigned char target_mask;
- unsigned char lun;
-#ifdef SUPPORT_TAGS
- unsigned char tag;
-#endif
- unsigned char msg[3];
- int __maybe_unused len;
- unsigned char __maybe_unused *data, __maybe_unused phase;
- 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);
-
- dsprintk(NDEBUG_RESELECTION, instance, "reselect\n");
-
- /*
- * 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(instance,
- STATUS_REG, SR_SEL, 0, 2 * HZ) < 0) {
- 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(instance,
- STATUS_REG, SR_REQ, SR_REQ, 2 * HZ) < 0) {
- do_abort(instance);
- return;
- }
-
-#if defined(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
- len = 1;
- data = msg;
- phase = PHASE_MSGIN;
- NCR5380_transfer_pio(instance, &phase, &len, &data);
-
- if (len) {
- do_abort(instance);
- return;
- }
-#endif
-
- 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;
-
-#if defined(SUPPORT_TAGS) && !defined(CONFIG_SUN3)
- /* If the phase is still MSGIN, the target wants to send some more
- * messages. In case it supports tagged queuing, this is probably a
- * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
- */
- tag = TAG_NONE;
- if (phase == PHASE_MSGIN && (hostdata->flags & FLAG_TAGGED_QUEUING)) {
- /* Accept previous IDENTIFY message by clearing ACK */
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
- len = 2;
- data = msg + 1;
- if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
- msg[1] == SIMPLE_QUEUE_TAG)
- tag = msg[2];
- dsprintk(NDEBUG_TAGS, instance, "reselect: target mask %02x, lun %d sent tag %d\n",
- target_mask, lun, tag);
- }
-#endif
-
- /*
- * 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
-#ifdef SUPPORT_TAGS
- && (tag == cmd->tag)
-#endif
- ) {
- list_del(&ncmd->list);
- tmp = cmd;
- break;
- }
- }
-
- if (tmp) {
- dsprintk(NDEBUG_RESELECTION | NDEBUG_QUEUES, instance,
- "reselect: removed %p from disconnected queue\n", tmp);
- } else {
-
-#ifdef SUPPORT_TAGS
- shost_printk(KERN_ERR, instance, "target bitmask 0x%02x lun %d tag %d not in disconnected queue.\n",
- target_mask, lun, tag);
-#else
- shost_printk(KERN_ERR, instance, "target bitmask 0x%02x lun %d not in disconnected queue.\n",
- target_mask, lun);
-#endif
- /*
- * Since we have an established nexus that we can't do anything
- * with, we must abort it.
- */
- do_abort(instance);
- return;
- }
-
-#if defined(CONFIG_SUN3)
- /* engage dma setup for the command we just saw */
- {
- void *d;
- unsigned long count;
-
- if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
- count = tmp->SCp.buffer->length;
- d = sg_virt(tmp->SCp.buffer);
- } else {
- count = tmp->SCp.this_residual;
- d = tmp->SCp.ptr;
- }
- /* setup this command for dma if not already */
- if (sun3_dma_setup_done != tmp &&
- sun3scsi_dma_xfer_len(count, tmp) > 0) {
- sun3scsi_dma_setup(instance, d, count,
- rq_data_dir(tmp->request));
- sun3_dma_setup_done = tmp;
- }
- }
-
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
-#endif
-
- /* Accept message by clearing ACK */
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
-
-#if defined(SUPPORT_TAGS) && defined(CONFIG_SUN3)
- /* If the phase is still MSGIN, the target wants to send some more
- * messages. In case it supports tagged queuing, this is probably a
- * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
- */
- tag = TAG_NONE;
- if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
- /* Accept previous IDENTIFY message by clearing ACK */
- NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
- len = 2;
- data = msg + 1;
- if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
- msg[1] == SIMPLE_QUEUE_TAG)
- tag = msg[2];
- dsprintk(NDEBUG_TAGS, instance, "reselect: target mask %02x, lun %d sent tag %d\n"
- target_mask, lun, tag);
- }
-#endif
-
- hostdata->connected = tmp;
- dsprintk(NDEBUG_RESELECTION, instance, "nexus established, target %d, lun %llu, tag %d\n",
- scmd_id(tmp), tmp->device->lun, tmp->tag);
-}
-
-
-/**
- * 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)) {
- 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);
- set_host_byte(cmd, DID_ERROR);
- complete_cmd(instance, cmd);
- }
-
-out:
- if (result == FAILED)
- dsprintk(NDEBUG_ABORT, instance, "abort: failed to abort %p\n", cmd);
- else
- 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;
-}
-
-
-/**
- * NCR5380_bus_reset - reset the SCSI bus
- * @cmd: SCSI command undergoing EH
- *
- * Returns SUCCESS
- */
-
-static int NCR5380_bus_reset(struct scsi_cmnd *cmd)
-{
- struct Scsi_Host *instance = cmd->device->host;
- struct NCR5380_hostdata *hostdata = shost_priv(instance);
- int i;
- unsigned long flags;
- struct NCR5380_cmd *ncmd;
-
- 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);
-
- do_reset(instance);
-
- /* 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 (list_del_cmd(&hostdata->unissued, cmd)) {
- cmd->result = DID_RESET << 16;
- cmd->scsi_done(cmd);
- }
-
- 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);
- cmd->scsi_done(cmd);
- }
- INIT_LIST_HEAD(&hostdata->disconnected);
-
- list_for_each_entry(ncmd, &hostdata->autosense, list) {
- struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd);
-
- set_host_byte(cmd, DID_RESET);
- 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;
- }
-
-#ifdef SUPPORT_TAGS
- free_all_tags(hostdata);
-#endif
- 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);
- spin_unlock_irqrestore(&hostdata->lock, flags);
-
- return SUCCESS;
-}
projects / users / hch / dma-mapping.git / commitdiff