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>

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>

The strn_pattern_cmp routine does not handle a blank name parameter
properly. The only patterns which should match a blank name are "*"
and an explicit "". If the function is passed a blank name in current
code, it will always match against the patt parameter. The bug manifests
itself as the device with the empty model name always matching the first
device in the DMA blacklist, forcing it to revert to PIO mode.
Signed-off-by: NAndrew Paprocki <andrew@ishiboo.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

ST9160821AS / 3.CCD does spurious completions too.  Blacklist it.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

* remove pointless pci_dev_to_dev() wrapper.  Just directly reference
  the embedded struct device like everyone else does.

* pata_cs5520: delete cs5520_remove_one(), it was a duplicate of
  ata_pci_remove_one()

* linux/libata.h: don't bother including linux/pci.h, we don't need it.
  Simply declare 'struct pci_dev' and assume interested parties will
  include the header, as they should be doing anyway.

* linux/libata.h: consolidate all CONFIG_PCI declarations into a
  single location in the header.
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

PMP registers used to be accessed with dedicated accessors ->pmp_read
and ->pmp_write.  During reset, those callbacks are called with the
port frozen so they should be able to run without depending on
interrupt delivery.  To achieve this, they were implemented polling.

However, as resetting the host port makes the PMP to isolate fan-out
ports until SError.X is cleared, resetting fan-out ports while port is
frozen doesn't buy much additional safety.

This patch updates libata PMP support such that PMP registers are
accessed using regular ata_exec_internal() mechanism and kills
->pmp_read/write() callbacks.  The following changes are made.

* PMP access helpers - sata_pmp_read_init_tf(), sata_pmp_read_val(),
  sata_pmp_write_init_tf() are folded into sata_pmp_read/write() which
  are now standalone PMP register access functions.

* sata_pmp_read/write() returns err_mask instead of rc.  This is
  consistent with other functions which issue internal commands and
  allows more detailed error reporting.

* ahci interrupt handler is modified to ignore BAD_PMP and
  spurious/illegal completion IRQs while reset is in progress.  These
  conditions are expected during reset.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add @timeout argument to ata_exec_internal[_sg]().  If 0, default
timeout ata_probe_timeout is used.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

ehi description field is used to carry LLD specific controller
description.  Sometimes, it's used without clearing before and LLD
description gets printed with exception information one more time.
Clear after printing.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

ST9160821AS / 3.ALD also does spurious NCQ completions.  Disable NCQ.
Signed-off-by: NTejun Heo <teheo@suse.de>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

HDT722516DLA380 does spurious completion of NCQ commands.  Blacklist
it.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Frans Pop <elendil@planet.nl>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Seagate Barracuda ST380817AS has troubles with NCQ. For example,
unpacking a tarball on an XFS filesystem gives this:

ata1.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x2 frozen
ata1.00: cmd 61/40:00:29:a3:98/00:00:00:00:00/40 tag 0 cdb 0x0 data 32768 out
         res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)

More info here:
http://lkml.org/lkml/2007/1/21/76

Blacklist it!
Signed-off-by: NPaolo Ornati <ornati@fastwebnet.it>
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Let's see what explodes.
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Correct handling of SRST reset sequences.  After an SRST it is undefined
whether the drive has gone back to PIO0.  In order to talk safely we should
talk slowly and carefully until we know.

Thus when we do the reset if the controller has a pio setup method we call it
to flip back to PIO 0 and a known state.  After the reset completes the
identify will then be done at the safe speed and the drive/controller will
pick suitable faster modes and reconfigure the controller to these timings.

As a side effect it means we force the controller to PIO 0 as we bring it up
which fixes funnies on a few systems where the BIOS firmware leaves us in an
interesting choice of modes, or embedded boxes with no firmware which come up
in random states.

For smart controllers there is nothing to do - they know about this
internally.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This is useful when debugging, handling problem systems, or for
distributions just to get the system installed so it can be sorted
out later.

This is a bit smarter than the old IDE one and lets you do

libata.dma=0	Disable all PATA DMA like old IDE
libata.dma=1	Disk DMA only
libata.dma=2	ATAPI DMA only
libata.dma=4	CF DMA only

(or combinations thereof - 0,1,3 being the useful ones I suspect)

(I've split CF as it seems to be a seperate case of pain and suffering
different to the others and caused by assorted PIO wired adapters etc)
Signed-off-by: NAlan Cox <alan@redhat.com>

[edited to work on SATA too, changing name from 'pata_dma' to 'dma']
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Implement sata_pmp_qc_defer_cmd_switch() - standard qc_defer for
command switching PMP support.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Hook PMP support into libata and enable it.  Connect SCR and probing
functions, and update ata_dev_classify() to detect PMP.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Implement Port Multiplier support.  To support PMP, a LLDD has to
supply ops->pmp_read() and pmp_write().  If non-null, ->pmp_attach and
->pmp_detach are called on PMP attach and detach, respectively.

->pmp_read/write() can be called while the port is frozen, so they
must be implemented by polling.  This patch supplies several helpers
to ease ->pmp_read/write() implementation.

Also, irq_handler and error_handler must be PMP aware.  Most of PMP
aware EH can be done by calling ata_pmp_do_eh() with appropriate
methods.  PMP EH uses separate set of reset methods and this patch
implements standard prereset, hardreset and postreset methods.

This patch only implements PMP support.  The next patch will integrate
PMP into the reset of libata and thus enable PMP support.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Restore the support for handling drives that report one sector too many
(ie SCSI not ATA style). This worked before the HPA update but was
removed in that process.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Blacklist HITACHI HDS7250SASUN500G and HITACHI HDS7225SBSUN250G
drives using wildcard matching.

Signed-off-by David Milburn <dmilburn@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

* The firmware version of ST3160812AS is "3.ADJ" no "3.AD".
* Add several entries from various sources.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

In ata_set_max_sectors(), the highest nibble in LBA28 mode was
missing.  This made drives sized between 8G and 128G with HPA turned
on to be resized to under 8G.  Fix it.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

AN serves multiple purposes.  For ATAPI, it's used for media change
notification.  For PMP, for downstream PHY status change notification.
Implement sata_async_notification() which demultiplexes AN.

To avoid unnecessary port events, ATAPI AN is not enabled if PMP is
attached but SNTF is not available.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Kriten Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Implement ap->nr_active_links (the number of links with active qcs),
ap->excl_link (pointer to link which can be used by ->qc_defer and is
cleared when a qc with ATA_QCFLAG_CLEAR_EXCL completes), and
ata_link_active().

These can be used by ->qc_defer() to implement proper command
exclusion.  This set of helpers seem enough for both sil24 (ATAPI
exclusion needed) and cmd-switching PMP.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Controllers which support PMP have various restrictions on which
combinations of commands are allowed to what number of devices
concurrently.  This patch implements ops->qc_defer() which determines
whether a qc can be issued at the moment or should be deferred.

If the function returns ATA_DEFER_LINK, the qc will be deferred until
a qc completes on the link.  If ATA_DEFER_PORT, until a qc completes
on any link.  The defer conditions are advisory and in general
ATA_DEFER_LINK can be considered as lower priority deferring than
ATA_DEFER_PORT.

ops->qc_defer() replaces fixed ata_scmd_need_defer().  For standard
NCQ/non-NCQ exclusion, ata_std_qc_defer() is implemented.  ahci and
sata_sil24 are converted to use ata_std_qc_defer().

ops->qc_defer() is heavier than the original mechanism because full qc
is prepped before determining to defer it, but various information is
needed to determine defer conditinos and fully translating a qc is the
only way to supply such information in generic manner.

IMHO, this shouldn't cause any noticeable performance issues as

* for most cases deferring occurs rarely (except for NCQ-aware
  cmd-switching PMP)
* translation itself isn't that expensive
* once deferred the command won't be repeated until another command
  completes which usually is a very long time cpu-wise.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Make a number of functions from libata-core.c and libata-eh.c global
to libata (drivers/ata/libata.h).  These will be used by PMP.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>