With ATAPI transfer chunk size properly programmed, libata PIO HSM
should be able to handle full spurious data chunks.  Also, it's a good
idea to suppress trailing data warning for misc ATAPI commands as
there can be many of them per command - for example, if the chunk size
is 16 and the drive tries to transfer 510 bytes, there can be 31
trailing data messages.

This patch makes the following updates to libata ATAPI PIO HSM
implementation.

* Make it drain full spurious chunks.

* Suppress trailing data warning message for misc commands.

* Put limit on how many bytes can be drained.

* If odd, round up consumed bytes and the number of bytes to be
  drained.  This gets the number of bytes to drain right for drivers
  which do 16bit PIO.

This patch is partial backport of improve-ATAPI-data-xfer patchset
pending for #upstream.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add two hooks - ata_acpi_dissociate() which is called during driver
detach after the whole host is shutdown and ata_acpi_on_disable()
which is called when a device is disabled.
Signed-off-by: NTejun heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

ata_port_detach() calls ata_dev_disable() with host lock held but
ata_dev_disable() should be called from EH context.  ata_port_detach()
steals EH context by setting ATA_PFLAG_UNLOADAING and flushing EH.
Drop locking around ata_dev_disable() and note that ata_port_detach()
owns EH context at that point.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Like ST380817AS / 3.42, ST3160023AS / 3.42 times out commands if NCQ
is used.  Blacklist it.  This is reported by Matheus Izvekov in the
following thread.

  http://thread.gmane.org/gmane.linux.ide/24202Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Matheus Izvekov <mizvekov@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

link->eh_info.serror is used to cache SError for controllers which
need it cleared from interrupt handler to clear IRQ.  It also should
be cleared after reset just like SError itself.

Make ata_std_postreset() clear link->eh_info.serror too and update
sata_sil such that it doesn't care about bookkeeping the value.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Spurious NCQ completion detection implemented in ahci was incorrect.
On AHCI receving and processing FISes and raising interrupts are not
interlocked and spurious interrupts are expected.

For example, if an interrupt occurs while interrupt handler is running
and the running interrupt handler handles the event the new IRQ
indicated, after IRQ handler finishes, it will be executed again
because IRQ pending bit is set by the new interrupt but there won't be
anything to process.

Please read the following message for more information.

  http://article.gmane.org/gmane.linux.ide/26012

This patch...

* Removes all spurious IRQ whining from ahci.  Spurious NCQ completion
  detection was completely wrong.  Spurious D2H Register FIS taught us
  that some early drives send spurious D2H Register FIS with I bit set
  while NCQ commands are in progress but none of recent drives does
  that and even the ones which show such behavior can do NCQ fine.

* Kills all NCQ blacklist entries which were added because of spurious
  NCQ completions.  I tracked down each commit and verified all
  removed ones are actually added because of spurious completions.

  WD740ADFD-00NLR1 wasn't deleted but moved upward because the drive
  not only had spurious NCQ completions but also is slow on sequential
  data transfers if NCQ is enabled.

  Maxtor 7V300F0 was added by 0e3dbc01
  from Alan Cox.  I can only find evidences that the drive only had
  troubles with spuruious completions by searching the mailing list.
  This entry needs to be verified and removed if it doesn't have other
  NCQ related problems.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

On Fri, 30 Nov 2007 14:34:11 +0200 (EET)
Meelis Roos <mroos@linux.ee> wrote:

> > Can you stick a stack trace in at that point ? That would help diagnose
> > it a great deal quicker.
>
> Finally done - found out hard way that BUG() is too bad and
> dump_st5ack() suits me better.

Thanks. This should fix the real cause, and also allow for port start to
fail politely with -ENODEV.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

libata: Add more TSST (Samsung/Toshiba) IDE drives with broken
cable detection validation bits.

signed-off-by: Peter Missel (peter.missel@onlinehome.de)
Acked-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

And next time I'll be able to find the ata tape spec easily...
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Per Mark's comments, maybe all ATAPI tape drives need ATA_HORKAGE_STUCK_ERR.
This patch applys ATA_HORKAGE_STUCK_ERR for all ATAPI tape drives.
Signed-off-by: NAlbert Lee <albertcc@tw.ibm.com>
Cc: Mark Lord <liml@rtr.ca>
Signed-off-by: NTejun Heo <htejun@gmail.com>

After an error condition, some ATAPI tape drives set DRQ=1 together
with ERR=1 when asking the host to transfer the CDB of the next packet
command (i.e. request sense).  This patch, a revised version of
Alan/Mark's previous patch, adds ATA_HORKAGE_STUCK_ERR to workaround
the problem by ignoring the ERR bit and proceed sending the CDB.
Signed-off-by: NAlbert Lee <albertcc@tw.ibm.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Mark Lord <liml@rtr.ca>
Signed-off-by: NTejun Heo <htejun@gmail.com>

This patch removes the following obsolete functions:
- libata-core.c: __sata_phy_reset()
- libata-core.c: sata_phy_reset()
- libata-eh.c: ata_qc_timeout()
- libata-eh.c: ata_eng_timeout()
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NTejun Heo <htejun@gmail.com>

Port / host stop calls used to be made from ata_host_release() which
is called after all hardware resources acquired after host allocation
are released.  This is wrong as port and host stop routines often
access the hardware.

Add separate devres for port / host stop which is invoked right after
IRQ is released but with all other hardware resources intact.  The
devres is added iff ->host_stop and/or ->port_stop exist.

This problem has been spotted by Mark Lord.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Mark Lord <liml@rtr.ca>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

In a presentation of true workmanship, pata_ali asserts IRQ
permanantly if the TF status register is read more than once when
there's no device attached to the port.

Avoid waiting polling for !0xff if it's PATA.  It's needed only for
some rare SATA devices anyway.

This problem is reported by Luca Tettamanti in bugzilla bug 9298.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Tested-By: NLuca Tettamanti <kronos.it@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

By default ata_host_activate() expects a valid IRQ in order to
successfully register the host. This patch enables a special case
for registering polling-only hosts that either don't have IRQs
or have buggy IRQ generation (either in terms of handling or
sensing), which otherwise work fine.

Hosts that want to use polling mode can simply set ATA_FLAG_PIO_POLLING
and pass in an invalid IRQ.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

One or two ancient drives predated the cable spec and didn't sent the
valid bits for the field. I had hoped to leave this out of libata as a
piece of historical annoyance but a recent CD drive shows the same bug so
we have to import support for it.

Same concept as Bartlomiej's changes old IDE except that as we have
centralised blacklists we can avoid keeping another private table of stuff
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

LPM seems to get hung up while disabling DIPM, and after thinking
about this a bit, I don't think we really need to manually disable it
anyway.
Signed-off-by: NKristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

There's nothing to be gained by configuring downstream links faster
than the upstream link and such configurations cause problems on
certain PMPs.  Limit downstream link speed by the upstream link speed.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

In sata_set_spd_needed(), if SControl read failed, it returned 0 and
skipped PHY speed configuration.  However, if SControl access fails,
it's far more logical to request PHY speed configuration.  Reverse the
logic.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Commands sent to ATAPI tape drives via the SCSI generic (sg) driver are
limited in the amount of data that they can transfer by the max_sectors
value.  The max_sectors value is currently calculated according to the
command set for disk drives, which doesn't apply to tape drives.  The
default max_sectors value of 256 limits ATAPI tape drive commands to
128 KB.  This patch against 2.6.24-rc1 increases the max_sectors value
for tape drives to 65535, which permits tape drive commands to transfer
just under 32 MB.

Tested with a SuperMicro PDSME motherboard, AHCI, and a Sony SDX-570V
SATA tape drive.

Note that some of the chipset drivers also set their own max_sectors
value, which may override the value set in libata-core.  I don't have
any of these chipsets to test, so I didn't go messing with them.  Also,
ATAPI devices other than tape drives may benefit from similar changes,
but I have only tape drives and disk drives to test.
Signed-off-by: NTony Battersby <tonyb@cybernetics.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Fix docbook format in the comments.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

drivers/ata/libata-core.c:768: warning: 'ata_lpm_enable' defined but not used
drivers/ata/libata-core.c:784: warning: 'ata_lpm_disable' defined but not used
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Device Initiated Power Management, which is defined
in SATA 2.5 can be enabled for disks which support it.
This patch enables DIPM when the user sets the link
power management policy to "min_power".

Additionally, libata drivers can define a function
(enable_pm) that will perform hardware specific actions to
enable whatever power management policy the user set up
for Host Initiated Power management (HIPM).
This power management policy will be activated after all
disks have been enumerated and intialized.  Drivers should
also define disable_pm, which will turn off link power
management, but not change link power management policy.

Documentation/scsi/link_power_management_policy.txt has additional
information.
Signed-off-by: NKristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

MAXTOR 7V300F0/VA111900 does spurious NCQ completions.  Add it to
blacklist.  This problem is reported by Carsten Otto.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Carsten Otto <c-otto@gmx.de>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Forcing PIO0 on reset was done inside ata_bus_softreset(), which is a
bit out of place as it should be applied to all resets - hard, soft
and implementation which don't use ata_bus_softreset().  Relocate it
such that...

* For new EH, it's done in ata_eh_reset() before calling prereset.

* For old EH, it's done before calling ap->ops->phy_reset() in
  ata_bus_probe().

This makes PIO0 forced after all resets.  Another difference is that
reset itself is done after PIO0 is forced.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Acked-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

On certain device/controller combination, 0xff status is asserted
after reset and doesn't get cleared during 150ms post-reset wait.  As
0xff status is interpreted as no device (for good reasons), this can
lead to misdetection on such cases.

This patch implements ata_wait_after_reset() which replaces the 150ms
sleep and waits upto ATA_TMOUT_FF_WAIT if status is 0xff.
ATA_TMOUT_FF_WAIT is currently 800ms which is enough for
HHD424020F7SV00 to get detected but not enough for Quantum GoVault
drive which is known to take upto 2s.

Without parallel probing, spending 2s on 0xff port would incur too
much delay on ata_piix's which use 0xff to indicate empty port and
doesn't have SCR register, so GoVault needs to wait till parallel
probing.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

ATA devices in SLEEP mode don't respond to any commands.  SRST is
necessary to wake it up.  Till now, when a command is issued to a
device in SLEEP mode, the command times out, which makes EH reset the
device and retry the command after that, causing a long delay.

This patch makes libata track SLEEP state and issue SRST automatically
if a command is about to be issued to a device in SLEEP.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Bruce Allen <ballen@gravity.phys.uwm.edu>
Cc: Andrew Paprocki <andrew@ishiboo.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Some commands need post-processing after successful completion.  This
was done in ata_scsi_qc_complete() till now but this has the following
problems.

* Post-command processing gets executed when qc is completed from EH.
  Some qc's are retried from EH with zero err_mask and thus triggers
  unnecessary/incorrect post-command processing.

* Command post processing doesn't belong to SAT layer.

* Link-wide revalidation was scheduled where device revalidation
  suffices.

This patch moves post-command processing to success completion path of
ata_qc_complete() which is travelled iff the command is going to be
completed without passing through EH and updates post-command
processing such that device-specific action is used.  While at it,
restructure code a bit for readability.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

After turning on DEBUG_SG I hit a fail:

kernel BUG at include/linux/scatterlist.h:50!

	ata_qc_issue
	ata_scsi_translate
	ipr_queuecommand
	scsi_dispatch_cmd
	scsi_request_fn
	elv_insert
	blk_execute_rq_nowait
	blk_execute_rq
	sg_io
	scsi_cmd_ioctl
	cdrom_ioctl
	sr_block_ioctl
	blkdev_driver_ioctl
	blkdev_ioctl
	block_ioctl
	do_ioctl
	vfs_ioctl
	sys_ioctl
	sg_ioctl_trans

It looks like ata_sg_setup is working on an uninitialised sg table. Call
sg_init_table to initialise it before use.
Signed-off-by: NAnton Blanchard <anton@samba.org>

Note: this patch will fix it, but you could also get away with just
doing the sg_init_table() once at qc creation time.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

I guess Windows didn't care about the command so neither did they
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

strn_pattern_cmp() and ata_port_detach() can become static.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Most drivers need to set length and offset as well, so may as well fold
those three lines into one.

Add sg_assign_page() for those two locations that only needed to set
the page, where the offset/length is set outside of the function context.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Another one doing spurious NCQ completions.  Blacklist it.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Luca Tettamanti <kronos.it@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Did a complete audit of these and found we have another error case.

ata_bus_softreset calls ata_check_status which means that it tries to do
an ioread8 on the port blindly and check versus 0xFF for an error.

It should of course be using the ap->ops method for this via chk_status,
and this bug causes a wrog status call on the NS87415 at least.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Tackle the relatively sane complaints of checkpatch --file.

The vast majority is indentation and whitespace changes, the rest are

* #include fixes
* printk KERN_xxx prefix addition
* BSS/initializer cleanups
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Fix libata kernel-doc parameter name.

Warning(linux-2.6.23-git13//drivers/ata/libata-core.c:1415): No description found for parameter 'sgl'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This converts libata to using the sg helpers for looking up sg
elements, instead of doing it manually.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>