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![Finn Thain](/assets/img/avatar_default.png)
I'm told that some targets are liable to disconnect a REQUEST SENSE command. Theoretically this would cause a command undergoing autosense to be moved onto the disconnected list. The bus reset handler must call complete_cmd() for these commands, otherwise the hostdata->sensing pointer will not get cleared. That would cause autosense processing to stall and a timeout or an incorrect scsi_eh_restore_cmnd() would eventually follow. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reported-by: Michael Schmitz <schmitzmic@gmail.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2467 lines
72 KiB
C
2467 lines
72 KiB
C
/*
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* NCR 5380 generic driver routines. These should make it *trivial*
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* to implement 5380 SCSI drivers under Linux with a non-trantor
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* architecture.
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*
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* Note that these routines also work with NR53c400 family chips.
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*
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* Copyright 1993, Drew Eckhardt
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* Visionary Computing
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* (Unix and Linux consulting and custom programming)
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* drew@colorado.edu
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* +1 (303) 666-5836
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*
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* For more information, please consult
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*
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* NCR 5380 Family
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* SCSI Protocol Controller
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* Databook
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*
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* NCR Microelectronics
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* 1635 Aeroplaza Drive
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* Colorado Springs, CO 80916
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* 1+ (719) 578-3400
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* 1+ (800) 334-5454
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*/
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/*
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* With contributions from Ray Van Tassle, Ingmar Baumgart,
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* Ronald van Cuijlenborg, Alan Cox and others.
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*/
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/* Ported to Atari by Roman Hodek and others. */
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/* Adapted for the Sun 3 by Sam Creasey. */
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/*
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* Design
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*
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* This is a generic 5380 driver. To use it on a different platform,
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* one simply writes appropriate system specific macros (ie, data
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* transfer - some PC's will use the I/O bus, 68K's must use
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* memory mapped) and drops this file in their 'C' wrapper.
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*
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* As far as command queueing, two queues are maintained for
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* each 5380 in the system - commands that haven't been issued yet,
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* and commands that are currently executing. This means that an
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* unlimited number of commands may be queued, letting
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* more commands propagate from the higher driver levels giving higher
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* throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
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* allowing multiple commands to propagate all the way to a SCSI-II device
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* while a command is already executing.
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*
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*
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* Issues specific to the NCR5380 :
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*
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* When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
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* piece of hardware that requires you to sit in a loop polling for
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* the REQ signal as long as you are connected. Some devices are
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* brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
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* while doing long seek operations. [...] These
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* broken devices are the exception rather than the rule and I'd rather
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* spend my time optimizing for the normal case.
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*
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* Architecture :
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*
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* At the heart of the design is a coroutine, NCR5380_main,
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* which is started from a workqueue for each NCR5380 host in the
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* system. It attempts to establish I_T_L or I_T_L_Q nexuses by
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* removing the commands from the issue queue and calling
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* NCR5380_select() if a nexus is not established.
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*
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* Once a nexus is established, the NCR5380_information_transfer()
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* phase goes through the various phases as instructed by the target.
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* if the target goes into MSG IN and sends a DISCONNECT message,
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* the command structure is placed into the per instance disconnected
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* queue, and NCR5380_main tries to find more work. If the target is
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* idle for too long, the system will try to sleep.
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*
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* If a command has disconnected, eventually an interrupt will trigger,
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* calling NCR5380_intr() which will in turn call NCR5380_reselect
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* to reestablish a nexus. This will run main if necessary.
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*
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* On command termination, the done function will be called as
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* appropriate.
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*
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* SCSI pointers are maintained in the SCp field of SCSI command
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* structures, being initialized after the command is connected
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* in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
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* Note that in violation of the standard, an implicit SAVE POINTERS operation
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* is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
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*/
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/*
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* Using this file :
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* This file a skeleton Linux SCSI driver for the NCR 5380 series
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* of chips. To use it, you write an architecture specific functions
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* and macros and include this file in your driver.
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*
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* These macros control options :
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* AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be
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* defined.
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*
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* AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
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* for commands that return with a CHECK CONDITION status.
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*
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* DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
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* transceivers.
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*
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* PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
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*
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* REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
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*
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* These macros MUST be defined :
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*
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* NCR5380_read(register) - read from the specified register
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*
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* NCR5380_write(register, value) - write to the specific register
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*
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* NCR5380_implementation_fields - additional fields needed for this
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* specific implementation of the NCR5380
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*
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* Either real DMA *or* pseudo DMA may be implemented
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*
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* NCR5380_dma_write_setup(instance, src, count) - initialize
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* NCR5380_dma_read_setup(instance, dst, count) - initialize
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* NCR5380_dma_residual(instance); - residual count
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*
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* The generic driver is initialized by calling NCR5380_init(instance),
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* after setting the appropriate host specific fields and ID. If the
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* driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
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* possible) function may be used.
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*/
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#ifndef NCR5380_io_delay
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#define NCR5380_io_delay(x)
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#endif
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#ifndef NCR5380_acquire_dma_irq
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#define NCR5380_acquire_dma_irq(x) (1)
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#endif
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#ifndef NCR5380_release_dma_irq
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#define NCR5380_release_dma_irq(x)
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#endif
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static int do_abort(struct Scsi_Host *);
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static void do_reset(struct Scsi_Host *);
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/**
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* initialize_SCp - init the scsi pointer field
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* @cmd: command block to set up
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*
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* Set up the internal fields in the SCSI command.
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*/
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static inline void initialize_SCp(struct scsi_cmnd *cmd)
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{
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/*
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* Initialize the Scsi Pointer field so that all of the commands in the
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* various queues are valid.
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*/
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if (scsi_bufflen(cmd)) {
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cmd->SCp.buffer = scsi_sglist(cmd);
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cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
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cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
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cmd->SCp.this_residual = cmd->SCp.buffer->length;
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} else {
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cmd->SCp.buffer = NULL;
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cmd->SCp.buffers_residual = 0;
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cmd->SCp.ptr = NULL;
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cmd->SCp.this_residual = 0;
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}
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cmd->SCp.Status = 0;
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cmd->SCp.Message = 0;
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}
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/**
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* NCR5380_poll_politely2 - wait for two chip register values
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* @instance: controller to poll
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* @reg1: 5380 register to poll
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* @bit1: Bitmask to check
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* @val1: Expected value
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* @reg2: Second 5380 register to poll
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* @bit2: Second bitmask to check
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* @val2: Second expected value
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* @wait: Time-out in jiffies
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*
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* Polls the chip in a reasonably efficient manner waiting for an
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* event to occur. After a short quick poll we begin to yield the CPU
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* (if possible). In irq contexts the time-out is arbitrarily limited.
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* Callers may hold locks as long as they are held in irq mode.
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*
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* Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.
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*/
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static int NCR5380_poll_politely2(struct Scsi_Host *instance,
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int reg1, int bit1, int val1,
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int reg2, int bit2, int val2, int wait)
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{
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struct NCR5380_hostdata *hostdata = shost_priv(instance);
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unsigned long deadline = jiffies + wait;
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unsigned long n;
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/* Busy-wait for up to 10 ms */
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n = min(10000U, jiffies_to_usecs(wait));
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n *= hostdata->accesses_per_ms;
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n /= 2000;
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do {
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if ((NCR5380_read(reg1) & bit1) == val1)
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return 0;
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if ((NCR5380_read(reg2) & bit2) == val2)
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return 0;
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cpu_relax();
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} while (n--);
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if (irqs_disabled() || in_interrupt())
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return -ETIMEDOUT;
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/* Repeatedly sleep for 1 ms until deadline */
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while (time_is_after_jiffies(deadline)) {
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schedule_timeout_uninterruptible(1);
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if ((NCR5380_read(reg1) & bit1) == val1)
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return 0;
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if ((NCR5380_read(reg2) & bit2) == val2)
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return 0;
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}
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return -ETIMEDOUT;
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}
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static inline int NCR5380_poll_politely(struct Scsi_Host *instance,
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int reg, int bit, int val, int wait)
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{
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return NCR5380_poll_politely2(instance, reg, bit, val,
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reg, bit, val, wait);
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}
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#if NDEBUG
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static struct {
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unsigned char mask;
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const char *name;
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} signals[] = {
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{SR_DBP, "PARITY"},
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{SR_RST, "RST"},
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{SR_BSY, "BSY"},
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{SR_REQ, "REQ"},
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{SR_MSG, "MSG"},
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{SR_CD, "CD"},
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{SR_IO, "IO"},
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{SR_SEL, "SEL"},
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{0, NULL}
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},
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basrs[] = {
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{BASR_END_DMA_TRANSFER, "END OF DMA"},
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{BASR_DRQ, "DRQ"},
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{BASR_PARITY_ERROR, "PARITY ERROR"},
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{BASR_IRQ, "IRQ"},
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{BASR_PHASE_MATCH, "PHASE MATCH"},
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{BASR_BUSY_ERROR, "BUSY ERROR"},
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{BASR_ATN, "ATN"},
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{BASR_ACK, "ACK"},
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{0, NULL}
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},
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icrs[] = {
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{ICR_ASSERT_RST, "ASSERT RST"},
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{ICR_ARBITRATION_PROGRESS, "ARB. IN PROGRESS"},
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{ICR_ARBITRATION_LOST, "LOST ARB."},
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{ICR_ASSERT_ACK, "ASSERT ACK"},
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{ICR_ASSERT_BSY, "ASSERT BSY"},
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{ICR_ASSERT_SEL, "ASSERT SEL"},
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{ICR_ASSERT_ATN, "ASSERT ATN"},
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{ICR_ASSERT_DATA, "ASSERT DATA"},
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{0, NULL}
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},
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mrs[] = {
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{MR_BLOCK_DMA_MODE, "BLOCK DMA MODE"},
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{MR_TARGET, "TARGET"},
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{MR_ENABLE_PAR_CHECK, "PARITY CHECK"},
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{MR_ENABLE_PAR_INTR, "PARITY INTR"},
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{MR_ENABLE_EOP_INTR, "EOP INTR"},
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{MR_MONITOR_BSY, "MONITOR BSY"},
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{MR_DMA_MODE, "DMA MODE"},
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{MR_ARBITRATE, "ARBITRATE"},
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{0, NULL}
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};
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/**
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* NCR5380_print - print scsi bus signals
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* @instance: adapter state to dump
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*
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* Print the SCSI bus signals for debugging purposes
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*/
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static void NCR5380_print(struct Scsi_Host *instance)
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{
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unsigned char status, data, basr, mr, icr, i;
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data = NCR5380_read(CURRENT_SCSI_DATA_REG);
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status = NCR5380_read(STATUS_REG);
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mr = NCR5380_read(MODE_REG);
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icr = NCR5380_read(INITIATOR_COMMAND_REG);
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basr = NCR5380_read(BUS_AND_STATUS_REG);
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printk(KERN_DEBUG "SR = 0x%02x : ", status);
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for (i = 0; signals[i].mask; ++i)
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if (status & signals[i].mask)
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printk(KERN_CONT "%s, ", signals[i].name);
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printk(KERN_CONT "\nBASR = 0x%02x : ", basr);
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for (i = 0; basrs[i].mask; ++i)
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if (basr & basrs[i].mask)
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printk(KERN_CONT "%s, ", basrs[i].name);
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printk(KERN_CONT "\nICR = 0x%02x : ", icr);
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for (i = 0; icrs[i].mask; ++i)
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if (icr & icrs[i].mask)
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printk(KERN_CONT "%s, ", icrs[i].name);
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printk(KERN_CONT "\nMR = 0x%02x : ", mr);
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for (i = 0; mrs[i].mask; ++i)
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if (mr & mrs[i].mask)
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printk(KERN_CONT "%s, ", mrs[i].name);
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printk(KERN_CONT "\n");
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}
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static struct {
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unsigned char value;
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const char *name;
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} phases[] = {
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{PHASE_DATAOUT, "DATAOUT"},
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{PHASE_DATAIN, "DATAIN"},
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{PHASE_CMDOUT, "CMDOUT"},
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{PHASE_STATIN, "STATIN"},
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{PHASE_MSGOUT, "MSGOUT"},
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{PHASE_MSGIN, "MSGIN"},
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{PHASE_UNKNOWN, "UNKNOWN"}
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};
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/**
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* NCR5380_print_phase - show SCSI phase
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* @instance: adapter to dump
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*
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* Print the current SCSI phase for debugging purposes
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*/
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static void NCR5380_print_phase(struct Scsi_Host *instance)
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{
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unsigned char status;
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int i;
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status = NCR5380_read(STATUS_REG);
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if (!(status & SR_REQ))
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shost_printk(KERN_DEBUG, instance, "REQ not asserted, phase unknown.\n");
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else {
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for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
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(phases[i].value != (status & PHASE_MASK)); ++i)
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;
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shost_printk(KERN_DEBUG, instance, "phase %s\n", phases[i].name);
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}
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}
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#endif
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static int probe_irq __initdata;
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/**
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* probe_intr - helper for IRQ autoprobe
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* @irq: interrupt number
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* @dev_id: unused
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* @regs: unused
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*
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* Set a flag to indicate the IRQ in question was received. This is
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* used by the IRQ probe code.
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*/
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static irqreturn_t __init probe_intr(int irq, void *dev_id)
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{
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probe_irq = irq;
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return IRQ_HANDLED;
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}
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/**
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* NCR5380_probe_irq - find the IRQ of an NCR5380
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* @instance: NCR5380 controller
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* @possible: bitmask of ISA IRQ lines
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*
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* Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ
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* and then looking to see what interrupt actually turned up.
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*/
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static int __init __maybe_unused NCR5380_probe_irq(struct Scsi_Host *instance,
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int possible)
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{
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struct NCR5380_hostdata *hostdata = shost_priv(instance);
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unsigned long timeout;
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int trying_irqs, i, mask;
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for (trying_irqs = 0, i = 1, mask = 2; i < 16; ++i, mask <<= 1)
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if ((mask & possible) && (request_irq(i, &probe_intr, 0, "NCR-probe", NULL) == 0))
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trying_irqs |= mask;
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timeout = jiffies + msecs_to_jiffies(250);
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probe_irq = NO_IRQ;
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/*
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* A interrupt is triggered whenever BSY = false, SEL = true
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* and a bit set in the SELECT_ENABLE_REG is asserted on the
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* SCSI bus.
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*
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* Note that the bus is only driven when the phase control signals
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* (I/O, C/D, and MSG) match those in the TCR, so we must reset that
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* to zero.
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*/
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NCR5380_write(TARGET_COMMAND_REG, 0);
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NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
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NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
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NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL);
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while (probe_irq == NO_IRQ && time_before(jiffies, timeout))
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schedule_timeout_uninterruptible(1);
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NCR5380_write(SELECT_ENABLE_REG, 0);
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NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
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for (i = 1, mask = 2; i < 16; ++i, mask <<= 1)
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if (trying_irqs & mask)
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free_irq(i, NULL);
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return probe_irq;
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}
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|
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/**
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* NCR58380_info - report driver and host information
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* @instance: relevant scsi host instance
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*
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* For use as the host template info() handler.
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*/
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static const char *NCR5380_info(struct Scsi_Host *instance)
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{
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struct NCR5380_hostdata *hostdata = shost_priv(instance);
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return hostdata->info;
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}
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static void prepare_info(struct Scsi_Host *instance)
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{
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struct NCR5380_hostdata *hostdata = shost_priv(instance);
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snprintf(hostdata->info, sizeof(hostdata->info),
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"%s, io_port 0x%lx, n_io_port %d, "
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"base 0x%lx, irq %d, "
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"can_queue %d, cmd_per_lun %d, "
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"sg_tablesize %d, this_id %d, "
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"flags { %s%s%s}, "
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"options { %s} ",
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instance->hostt->name, instance->io_port, instance->n_io_port,
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instance->base, instance->irq,
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instance->can_queue, instance->cmd_per_lun,
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instance->sg_tablesize, instance->this_id,
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hostdata->flags & FLAG_DMA_FIXUP ? "DMA_FIXUP " : "",
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hostdata->flags & FLAG_NO_PSEUDO_DMA ? "NO_PSEUDO_DMA " : "",
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hostdata->flags & FLAG_TOSHIBA_DELAY ? "TOSHIBA_DELAY " : "",
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#ifdef DIFFERENTIAL
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"DIFFERENTIAL "
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#endif
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#ifdef PARITY
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"PARITY "
|
|
#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 NCR5380_init(struct Scsi_Host *instance, int flags)
|
|
{
|
|
struct NCR5380_hostdata *hostdata = shost_priv(instance);
|
|
int i;
|
|
unsigned long deadline;
|
|
|
|
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;
|
|
|
|
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;
|
|
}
|
|
|
|
hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
|
|
|
|
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;
|
|
}
|
|
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(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) {
|
|
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);
|
|
|
|
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.
|
|
*/
|
|
|
|
/* 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(((instance->irq == NO_IRQ) ? 0 : 1), cmd->device->lun);
|
|
|
|
len = 1;
|
|
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;
|
|
hostdata->busy[cmd->device->id] |= 1 << cmd->device->lun;
|
|
|
|
#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);
|
|
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(instance, d, c);
|
|
else
|
|
result = NCR5380_dma_send_setup(instance, 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(instance, d, c);
|
|
else
|
|
result = NCR5380_dma_send_setup(instance, 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(instance, 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(instance, 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(instance,
|
|
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)
|
|
{
|
|
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) {
|
|
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;
|
|
}
|
|
|
|
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);
|
|
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.
|
|
*/
|
|
|
|
transfersize = 0;
|
|
if (!cmd->device->borken)
|
|
transfersize = NCR5380_dma_xfer_len(instance, cmd, phase);
|
|
|
|
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;
|
|
sink = 1;
|
|
do_abort(instance);
|
|
cmd->result = DID_ERROR << 16;
|
|
/* XXX - need to source or sink data here, as appropriate */
|
|
}
|
|
} 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;
|
|
}
|
|
#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;
|
|
|
|
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:
|
|
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);
|
|
|
|
/* 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.
|
|
*/
|
|
|
|
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);
|
|
|
|
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;
|
|
}
|
|
|
|
#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 {
|
|
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.
|
|
*/
|
|
do_abort(instance);
|
|
return;
|
|
}
|
|
|
|
#ifdef CONFIG_SUN3
|
|
{
|
|
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;
|
|
}
|
|
|
|
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 /* 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)) {
|
|
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);
|
|
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);
|
|
|
|
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;
|
|
}
|
|
|
|
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;
|
|
}
|