SCSI bus protocol sometimes requires monitoring two related conditions
simultaneously. Enhance NCR5380_poll_politely() for this purpose, and
put it to use in the arbitration algorithm. It will also find use in
pseudo DMA.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Because interrupt handling is crucial to the core driver(s), all wrapper
drivers need to agree on this code. This patch removes discrepancies.
NCR5380_intr() in NCR5380.c has the following pointless loop that differs
from the code in atari_NCR5380.c.
done = 1;
do {
/* ... */
} while (!done);
The 'done' flag gets cleared when a reconnected command is to be processed
from the work queue. But in NCR5380.c, the flag is also used to cause the
interrupt conditions to be re-examined. Perhaps this was because
NCR5380_reselect() was expected to cause another interrupt, or perhaps
the remaining present interrupt conditions need to be handled after the
NCR5380_reselect() call?
Actually, both possibilities are bogus, as is the loop itself. It seems
have been overlooked in the hit-and-miss removal of scsi host instance
list iteration many years ago; see history/history.git commit 491447e1fcff
("[PATCH] next NCR5380 updates") and commit 69e1a9482e57 ("[PATCH] fix up
NCR5380 private data"). See also my earlier patch, "Always retry
arbitration and selection".
The datasheet says, "IRQ can be reset simply by reading the Reset
Parity/Interrupt Register". So don't treat the chip IRQ like a
level-triggered interrupt. Of the conditions that set the IRQ flag,
some are level-triggered and some are edge-triggered, which means IRQ
itself must be edge-triggered.
Some interrupt conditions are latched and some are not. Before clearing
the chip IRQ flag, clear all state that may cause it to be raised. That
means clearing the DMA Mode and Busy Monitor bits in the Mode Register
and clearing the host ID in the Select Enable register.
Also clean up some printk's and some comments. Keep atari_NCR5380.c and
NCR5380.c in agreement.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The complex main_running/queue_main mechanism is peculiar to
atari_NCR5380.c. It isn't SMP safe and offers little value given that
the work queue already offers concurrency management. Remove this
complexity to bring atari_NCR5380.c closer to NCR5380.c.
It is not a good idea to call the information transfer state machine from
queuecommand because, according to Documentation/scsi/scsi_mid_low_api.txt
that could happen in soft irq context. Fix this.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When there is a queued command and no connected command, NCR5380_select()
is called and arbitration begins. The chip waits for BUS FREE once the
MR_ARBITRATE bit in the mode register is enabled. That means there is
no need to wait for BUS FREE after disconnecting.
There is presently no polling for BUS FREE after sending an ABORT or
other message that might lead to disconnection. It only happens after
COMMAND COMPLETE or DISCONNECT messages, which seems inconsistent.
Remove the polling for !BSY in the COMMAND COMPLETE and DISCONNECT
cases.
BTW, the comments say "avoid nasty timeouts" and perhaps BUS FREE polling
was somehow helpful back in Linux v0.99.14u, when it was introduced.
The relevant timeout is presently 1 second (for bus arbitration).
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Allow target selection to fail with a timeout instead of waiting in
infinite loops. This gets rid of the unused NCR_TIMEOUT macro, it is more
defensive and has proved helpful in debugging.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use timeouts in do_abort() in atari_NCR5380.c instead of infinite loops.
Also fix the kernel-doc comment. Keep the two core driver forks in sync.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Some old drivers partially implemented support for linked commands using
a "proposed" next_link pointer in struct scsi_cmnd that never actually
existed. Remove this code.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Remove the DEF_SCSI_QCMD macro (already removed from atari_NCR5380.c). The
lock provided by DEF_SCSI_QCMD is only needed for queue data structures.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
According to the SCSI-2 draft revision 10L, atari_NCR5380.c is correct
when it says that the phase lines are valid up until ACK is negated
following the transmission of the last byte in MESSAGE IN phase. This is
true for all information transfer phases, from target to initiator.
Sample the phase bits in STATUS_REG so that NCR5380_transfer_pio() can
return the correct result. The return value is presently unused (perhaps
because of bugs like this) but this change at least fixes the caller's
phase variable, which is passed by reference.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The atari_NCR5380.c and NCR5380.c core drivers differ in their handling of
target disconnection. This is partly because atari_NCR5380.c had all of
the polling and sleeping removed to become entirely interrupt-driven, and
it is partly because of damage done to NCR5380.c after atari_NCR5380.c was
forked. See commit 37cd23b44929 ("Linux 2.1.105") in history/history.git.
The polling changes that were made in v2.1.105 are questionable at best:
if REQ is not already asserted when NCR5380_transfer_pio() is invoked, and
if the expected phase is DATA IN or DATA OUT, the function will schedule
main() to execute after USLEEP_SLEEP jiffies and then return. The problems
here are the expected REQ timing and the sleep interval*. Avoid this issue
by using NCR5380_poll_politely() instead of scheduling main().
The atari_NCR5380.c core driver requires the use of the chip interrupt and
always permits target disconnection. It sets the cmd->device->disconnect
flag when a device disconnects, but never tests this flag.
The NCR5380.c core driver permits disconnection only when
instance->irq != NO_IRQ. It sets the cmd->device->disconnect flag when
a device disconnects and it tests this flag in a couple of places:
1. During NCR5380_information_transfer(), following COMMAND OUT phase,
if !cmd->device->disconnect, the initiator will take a guess as to
whether or not the target will then choose to go to MESSAGE IN phase
and disconnect. If the driver guesses "yes", it will schedule main()
to execute after USLEEP_SLEEP jiffies and then return there.
Unfortunately the driver may guess "yes" even after it has denied
the target the disconnection privilege. When the target does not
disconnect, the sleep can be beneficial, assuming the sleep interval
is appropriate (mostly it is not*).
And even if the driver guesses "yes" correctly, and the target would
then disconnect, the driver still has to go through the MESSAGE IN
phase in order to get to BUS FREE phase. The main loop can do nothing
useful until BUS FREE, and sleeping just delays the phase transition.
2. If !cmd->device->disconnect and REQ is not already asserted when
NCR5380_information_transfer() is invoked, the function polls for REQ
for USLEEP_POLL jiffies. If REQ is not asserted, it then schedules
main() to execute after USLEEP_SLEEP jiffies and returns.
The idea is apparently to yeild the CPU while waiting for REQ.
This is conditional upon !cmd->device->disconnect, but there seems
to be no rhyme or reason for that. For example, the flag may be
unset because disconnection privilege was denied because the driver
has no IRQ. Or the flag may be unset because the device has never
needed to disconnect before. Or if the flag is set, disconnection
may have no relevance to the present bus phase.
Another deficiency of the existing algorithm is as follows. When the
driver has no IRQ, it prevents disconnection, and generally polls and
sleeps more than it would normally. Now, if the driver is going to poll
anyway, why not allow the target to disconnect? That way the driver can do
something useful with the bus instead of polling unproductively!
Avoid this pointless latency, complexity and guesswork by using
NCR5380_poll_politely() instead of scheduling main().
* For g_NCR5380, the time intervals for USLEEP_SLEEP and USLEEP_POLL are
200 ms and 10 ms, respectively. They are 20 ms and 200 ms respectively
for the other NCR5380 drivers. There doesn't seem to be any reason for
this discrepancy. The timing seems to have no relation to the type of
adapter. Bizarrely, the timing in g_NCR5380 seems to relate only to one
particular type of target device. This patch attempts to solve the
problem for all NCR5380 drivers and all target devices.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Follow the example of the atari_NCR5380.c core driver and adopt the
NCR5380_dma_xfer_len() hook. Implement NCR5380_dma_xfer_len() for dtc.c
and g_NCR5380.c to take care of the limitations of these cards. Keep the
default for drivers using PSEUDO_DMA.
Eliminate the unused macro LIMIT_TRANSFERSIZE.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If NCR5380_select() returns -1, it means arbitration was lost or selection
failed and should be retried. If the main loop simply terminates when there
are still commands on the issue queue, they will remain queued until they
expire.
Fix this by clearing the 'done' flag after selection failure or lost
arbitration.
The "else break" clause in NCR5380_main() that gets removed here appears
to be a vestige of a long-gone loop that iterated over host instances.
See commit 491447e1fcff ("[PATCH] next NCR5380 updates") in
history/history.git.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Linux v2.1.105 changed the algorithm for polling for the BSY signal
in NCR5380_select() and NCR5380_main().
Presently, this code has a bug. Back then, NCR5380_set_timer(hostdata, 1)
meant reschedule main() after sleeping for 10 ms. Repeated 25 times this
provided the recommended 250 ms selection time-out delay. This got broken
when HZ became configurable.
We could fix this but there's no need to reschedule the main loop. This
BSY polling presently happens when the NCR5380_main() work queue item
calls NCR5380_select(), which in turn schedules NCR5380_main(), which
calls NCR5380_select() again, and so on.
This algorithm is a deviation from the simpler one in atari_NCR5380.c.
The extra complexity and state is pointless. There's no reason to
stop selection half-way and return to to the main loop when the main
loop can do nothing useful until selection completes.
So just poll for BSY. We can sleep while polling now that we have a
suitable workqueue.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When in process context, sleep during polling if doing so won't add
significant latency. In interrupt context or if the lock is held, poll
briefly then give up. Keep both core drivers in sync.
Calibrate busy-wait iterations to allow for variation in chip register
access times between different 5380 hardware implementations.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Allocate a work queue that will permit busy waiting and sleeping. This
means NCR5380_init() can potentially fail, so add this error path.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
NCR5380.c is not compliant with the SCSI-2 standard (at least, not with
the draft revision 10L that I have to refer to). The selection algorithm
in atari_NCR5380.c is correct, so use that.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If a target disappears from the SCSI bus, NCR5380_select() may
subsequently fail with a time-out. In this situation, scsi_done is
called and NCR5380_select() returns 0. Both hostdata->connected and
hostdata->selecting are NULL and the main loop should proceed with
the next command in the issue queue. Clarify this logic.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Remove the restart_select and targets_present variables introduced in
Linux v1.1.38. The former was used only for a questionable debug printk
and the latter "so we can call a select failure a retryable condition".
Well, retrying select failure in general is a different problem to a
target that doesn't assert BSY. We need to handle these two cases
differently; the latter case can be left to the SCSI ML.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The "failed" label in NCR5380_select() is not helpful. Some failures
return 0, others -1. Use return instead of goto to improve clarity and
brevity, like atari_NCR5380.c does. Fix the relevant comments.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Remove the duplicate write to the Select Enable Register that appeared
in v1.1.38.
Also remove the redundant write to Initiator Command Register prior to
calling do_abort().
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The aborted flag was introduced in v1.1.38 but never used. Remove it.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Make use of do_reset() in the bus reset handler in atari_NCR5380.c. The
version in NCR5380.c already does so. Keep them in sync.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The atari_NCR5380.c core driver now takes care of bus reset upon driver
initialization if required (same as NCR5380.c). Move the Toshiba CD-ROM
support into the core driver, enabled with a host flag, so that all
NCR5380 drivers can make use of it.
Drop the RESET_BOOT macros and the ATARI_SCSI_RESET_BOOT and
ATARI_SCSI_TOSHIBA_DELAY Kconfig symbols, which are now redundant.
Remove the atari_scsi_reset_boot(), mac_scsi_reset_boot() and
sun3_scsi_reset_boot() routines. None of this duplicated code is needed
now that all drivers can use NCR5380_maybe_reset_bus().
This brings atari_scsi, mac_scsi and sun3_scsi into line with all of the
other NCR5380 drivers.
The bus reset may raise an interrupt. That would be new behaviour for
atari_scsi only when CONFIG_ATARI_SCSI_RESET_BOOT=n. The ST DMA interrupt
is not assigned to atari_scsi at this stage, so
CONFIG_ATARI_SCSI_RESET_BOOT=y may well be problematic already.
Regardless, do_reset() now raises and clears the interrupt within
local_irq_save/restore which should avoid problems.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Merge the bus reset code from NCR5380.c into atari_NCR5380.c. This allows
for removal of a lot of duplicated code conditional on the RESET_BOOT
macro (in the next patch).
The atari_NCR5380.c fork lacks the do_reset() and NCR5380_poll_politely()
routines from NCR5380.c, so introduce them. They are indispensible. Keep
the two implementations in sync.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Instances of var * HZ / 1000 are replaced by msecs_to_jiffies(var).
In addition some timing constants that assumed HZ 100 were adjusted
to HZ independent settings based on review comments from Michael Schmitz
<schmitzmic@gmail.com> and review of the original drivers in 1.0.31 and
2.2.16.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Acked-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Using seq_putc to print a single character saves at least a strlen()
call and a memory access, and may also give a small .text reduction.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Using seq_printf to print a simple string is a lot more expensive than
it needs to be, since seq_puts exists. Replace seq_printf with
seq_puts when possible.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>
There's no need to run the cmd->done callback for aborted commands. Remove
the old EH code and the RESET_RUN_DONE macro.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Unlike NCR5380.c, the atari_NCR5380.c core driver is limited to a single
instance because co-routine state is stored globally.
Fix this by removing the static scsi host pointer. For the co-routine,
obtain this pointer from the work_struct pointer instead. For the interrupt
handler, obtain it from the dev_id argument.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The atari_NCR5380.c core driver keeps some per-host data in a static
variable which limits the driver to a single instance. Fix this by moving
TagAlloc to the hostdata struct.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The static variable setup_use_tagged_queuing is declared in mac_scsi.c,
sun3_scsi.c and atari_scsi.c and doesn't belong in the core driver.
None of the other NCR5380 drivers suffer from this layering issue which
makes merging the core drivers more difficult and will likely hinder plans
for future use of platform data to configure the driver.
Replace the static variable with a host flag. This way it can be reported
along with the other flags.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The NCR5380.c core driver has moved on since the atari_NCR5380.c fork.
Some of those changes are also relevant to atari_NCR5380.c so apply them
there as well.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
There is very little difference between the sun3_NCR5380.c core driver
and atari_NCR5380.c. The former is a fork of the latter.
Merge the sun3_NCR5380.c core driver into atari_NCR5380.c so that
sun3_scsi.c can adopt the latter and the former can be deleted.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Simplify falcon_release_lock_if_possible() by making callers responsible for
disabling local IRQ's, which they must do anyway to correctly synchronize
the ST DMA "lock" with core driver data structures. Move this
synchronization logic to the core driver with which it is tightly coupled.
Other LLD's like sun3_scsi and mac_scsi that can make use of this core
driver can just stub out the NCR5380_acquire_dma_irq() and
NCR5380_release_dma_irq() calls so the compiler will eliminate the
ST DMA code.
Remove a redundant local_irq_save/restore pair (irq's are disabled for
interrupt handlers these days). Revise the locking for
atari_scsi_bus_reset(): use local_irq_save/restore() instead of
atari_turnoff/turnon_irq(). There is no guarantee that atari_scsi still
holds the ST DMA lock during EH, so atari_turnoff/turnon_irq() could
end up dropping an IDE or floppy interrupt.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Make the atari_NCR5380.c core driver usable by sun3_scsi, mac_scsi and
others by moving some of the Falcon-specific code out of the core driver:
!IS_A_TT, atari_read_overruns and falcon_dont_release. Replace these with
hostdata variables and flags. FLAG_CHECK_LAST_BYTE_SENT is unused in
atari_NCR5380.c so don't set it.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
atari_NCR5380.c enables its IRQ when it is already enabled. Sun3 doesn't
use the ENABLE_IRQ/DISABLE_IRQ cruft. Remove it.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Don't disable irqs when waiting for the ST DMA "lock"; its release may
require an interrupt.
Introduce stdma_try_lock() for use in soft irq context. atari_scsi now tells
the SCSI mid-layer to defer queueing a command if the ST DMA lock is not
available, as per Michael's patch:
http://marc.info/?l=linux-m68k&m=139095335824863&w=2
The falcon_got_lock variable is race prone: we can't disable IRQs while
waiting to acquire the lock, so after acquiring it there must be some
interval during which falcon_got_lock remains false. Introduce
stdma_is_locked_by() to replace falcon_got_lock.
The falcon_got_lock tests in the EH handlers are incorrect these days. It
can happen that an EH handler is called after a command completes normally.
Remove these checks along with falcon_got_lock.
Also remove the complicated and racy fairness wait queues. If fairness is an
issue (when SCSI competes with IDE for the ST DMA interrupt), the solution
is likely to be a lower value for host->can_queue.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Convert Scsi_Cmnd to struct scsi_cmnd and drop the #include "scsi.h".
The sun3_NCR5380.c core driver already uses struct scsi_cmnd so converting
the other core drivers reduces the diff which makes them easier to unify.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The *_RELEASE macros don't tell me anything. In some cases the version in
the macro contradicts the version in the comments. Anyway, the Linux kernel
version is sufficient information. Remove these macros to improve readability.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
If the host->info() method is not set, then host->name is used by default.
For atari_scsi, that is exactly the same text. So remove the redundant
info() method. Keep sun3_scsi.c in line with atari_scsi.
Some NCR5380 drivers return an empty string from the info() method
(arm/cumana_1.c arm/oak.c mac_scsi.c) while other drivers use the default
(dmx3191d dtc.c g_NCR5380.c pas16.c t128.c).
Implement a common info() method to replace a lot of duplicated code which
the various drivers use to announce the same information.
This replaces most of the (deprecated) show_info() output and all of the
NCR5380_print_info() output. This also eliminates a bunch of code in
g_NCR5380 which just duplicates functionality in the core driver.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The NCR5380_STATS option is only enabled by g_NCR5380 yet it adds
clutter to all three core drivers. The atari_NCR5380.c and sun3_NCR5380.c
core drivers have a slightly different implementation of the
NCR5380_STATS option.
Out of all ten NCR5380 drivers, only one of them (g_NCR5380) actually
has the code to report on the collected stats. Aside from being unreadable,
that code seems to be broken because there's no initialization of timebase.
sun3_NCR5380.c and atari_NCR5380.c have the timebase initialization but
lack the code to report the stats.
Remove all of this code to improve readability and reduce divergence
between the three core drivers.
This patch and the next one completely eliminate the PRINTP and ANDP
pre-processor abuse.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Every NCR5380 driver sets AUTOSENSE so it need not be optional (and the
mid-layer expects it). Remove this redundant macro to improve readability.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Both atari_NCR5380.c and sun3_NCR5380.c core drivers #undef TAG_NONE and
then redefine it. But the original definition is unused because NCR5380.c
lacks support for tagged queueing. So just define it once.
The TAG_NEXT macro only appears in the arguments to NCR5380_select() calls.
But that routine doesn't use its tag argument as the tag was already
assigned in NCR5380_main(). So remove the unused argument and the macro.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Make use of the host template static initializer instead of assigning
handlers at run-time. Move __maybe_unused qualifiers from declarations
to definitions. Move the atari_scsi_bus_reset() wrapper after the
definition of NCR5380_bus_reset(). All of the host template handler
prototypes are now redundant so remove them.
The write_info() handler is only relevant to drivers using PSEUDO_DMA so
this patch fixes the compiler warning in atari_NCR5380.c and sun3_NCR5380.c:
CC drivers/scsi/atari_scsi.o
drivers/scsi/NCR5380.h:329: warning: 'NCR5380_write_info' declared 'static' but never defined
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The .eh_abort_handler needs to return SUCCESS, FAILED, or
FAST_IO_FAIL. So fixup all callers to adhere to this requirement.
Reviewed-by: Robert Elliott <elliott@hp.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Calling scsi_print_command should not be necessary during abort;
if the information is required one should enable scsi logging.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The SCSI standard defines 64-bit values for LUNs, and large arrays
employing large or hierarchical LUN numbers become more and more
common.
So update the linux SCSI stack to use 64-bit LUN numbers.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
All three NCR5380 core driver implementations share the same NCR5380.h
header file so they need to agree on certain macro definitions.
The flag bit used by the NDEBUG_MERGING macro in atari_NCR5380 and
sun3_NCR5380 collides with the bit used by NDEBUG_LISTS.
Moreover, NDEBUG_ABORT appears in NCR5380.c so it should be defined in
NCR5380.h rather than in each of the many drivers using that core.
An undefined NDEBUG_ABORT macro caused compiler errors and led to dodgy
workarounds in the core driver that can now be removed.
(See commits f566a576bc and
185a7a1cd79b9891e3c17abdb103ba1c98d6ca7a.)
Move all of the NDEBUG_ABORT, NDEBUG_TAGS and NDEBUG_MERGING macro
definitions into NCR5380.h where all the other NDEBUG macros live.
Also, incorrect "#ifdef NDEBUG" becomes "#if NDEBUG" to fix the warning:
drivers/scsi/mac_scsi.c: At top level:
drivers/scsi/NCR5380.c:418: warning: 'NCR5380_print' defined but not used
drivers/scsi/NCR5380.c:459: warning: 'NCR5380_print_phase' defined but not used
The debugging code is now enabled when NDEBUG != 0.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Acked-by: Sam Creasey <sammy@sammy.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
All NCR5380 drivers already include the NCR5380.h header. Better to
adopt those macros rather than have three variations on them.
Moreover, the macros in NCR5380.h are preferable because the atari_NCR5380
and sun3_NCR5380 versions are inflexible. For example, they can't accomodate
dprintk(NDEBUG_MAIN | NDEBUG_QUEUES, ...)
Replace the *_PRINTK macros from atari_NCR5380.h and sun3_NCR5380.h with
the equivalent macros from NCR5380.h.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Acked-by: Sam Creasey <sammy@sammy.net>
Acked-by: Michael Schmitz <schmitz@debian.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
