Logically, SCR access ops should take @link; however, there was no
compelling reason to convert all SCR access ops when adding @link
abstraction as there's one-to-one mapping between a port and a non-PMP
link.  However, that assumption won't hold anymore with the scheduled
addition of slave link.

Make SCR access ops per-link.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

The following commit (4c9bf4e7):
libata: replace tf_read with qc_fill_rtf for non-SFF drivers

Broke the sata_fsl.c driver in 2.6.26-rc.  I know the following patch fixes
the issue, it clearly also adds port multipler support.  The current
2.6.26-rc driver is broken.

On boot with debug enabled we get something like (w/o this patch):

spurious interrupt!!, CC = 0x1
interrupt status 0x1
xx_scr_read, reg_in = 1
spurious interrupt!!, CC = 0x1
interrupt status 0x1
xx_scr_read, reg_in = 1
spurious interrupt!!, CC = 0x1
interrupt status 0x1
xx_scr_read, reg_in = 1

.. continues for ever.

This change fixes this as a side effect of adding port multiplier support.
Signed-off-by: NAshish Kalra <ashish.kalra@freescale.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

it's ata_link, not ata_linke
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, SATA softresets should do link onlineness check before
actually performing SRST protocol but it doesn't really belong to
softreset.

This patch moves onlineness check in softreset to ata_eh_reset() and
ata_eh_followup_srst_needed() to clean up code and help future sata_mv
changes which need clear separation between SCR and TF accesses.

sata_fsl is peculiar in that its softreset really isn't softreset but
combination of hardreset and softreset.  This patch adds dummy private
->prereset to keep the current behavior but the driver really should
implement separate hard and soft resets and return -EAGAIN from
hardreset if it should be follwed by softreset.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

ap->ioaddr is to carry addresses for TF and BMDMA registers of a SFF
controller, don't abuse it in non-SFF controllers.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Now that all SFF stuff is separated out of core layer, core layer
doesn't call ops->[alt_]check_status().  In fact, no one calls them
for non-SFF drivers anymore.  Kill them.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Now that all SFF stuff is separated out of core layer, core layer
doesn't call ops->tf_read directly.  It gets called only via
ops->qc_fill_rtf() for non-SFF drivers.  This patch directly
implements private ops->qc_fill_rtf() for non-SFF controllers and kill
ops->tf_read().

This is much cleaner for non-SFF controllers as some of them have to
cache SFF register values in private data structure and report the
cached values via ops->tf_read().  Also, ops->tf_read() gets nasty for
controllers which don't have clear notion of TF registers when
operation is not in progress.

As this change makes default ops->qc_fill_rtf unnecessary, move
ata_sff_qc_fill_rtf() form ata_base_port_ops to ata_sff_port_ops where
it belongs.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Add sff_ prefix to SFF specific port ops.

This rename is in preparation of separating SFF support out of libata
core layer.  This patch strictly renames ops and doesn't introduce any
behavior difference.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Currently reset methods are not specified directly in the
ata_port_operations table.  If a LLD wants to use custom reset
methods, it should construct and use a error_handler which uses those
reset methods.  It's done this way for two reasons.

First, the ops table already contained too many methods and adding
four more of them would noticeably increase the amount of necessary
boilerplate code all over low level drivers.

Second, as ->error_handler uses those reset methods, it can get
confusing.  ie. By overriding ->error_handler, those reset ops can be
made useless making layering a bit hazy.

Now that ops table uses inheritance, the first problem doesn't exist
anymore.  The second isn't completely solved but is relieved by
providing default values - most drivers can just override what it has
implemented and don't have to concern itself about higher level
callbacks.  In fact, there currently is no driver which actually
modifies error handling behavior.  Drivers which override
->error_handler just wraps the standard error handler only to prepare
the controller for EH.  I don't think making ops layering strict has
any noticeable benefit.

This patch makes ->prereset, ->softreset, ->hardreset, ->postreset and
their PMP counterparts propoer ops.  Default ops are provided in the
base ops tables and drivers are converted to override individual reset
methods instead of creating custom error_handler.

* ata_std_error_handler() doesn't use sata_std_hardreset() if SCRs
  aren't accessible.  sata_promise doesn't need to use separate
  error_handlers for PATA and SATA anymore.

* softreset is broken for sata_inic162x and sata_sx4.  As libata now
  always prefers hardreset, this doesn't really matter but the ops are
  forced to NULL using ATA_OP_NULL for documentation purpose.

* pata_hpt374 needs to use different prereset for the first and second
  PCI functions.  This used to be done by branching from
  hpt374_error_handler().  The proper way to do this is to use
  separate ops and port_info tables for each function.  Converted.
Signed-off-by: NTejun Heo <htejun@gmail.com>

libata lets low level drivers build ata_port_operations table and
register it with libata core layer.  This allows low level drivers
high level of flexibility but also burdens them with lots of
boilerplate entries.

This becomes worse for drivers which support related similar
controllers which differ slightly.  They share most of the operations
except for a few.  However, the driver still needs to list all
operations for each variant.  This results in large number of
duplicate entries, which is not only inefficient but also error-prone
as it becomes very difficult to tell what the actual differences are.

This duplicate boilerplates all over the low level drivers also make
updating the core layer exteremely difficult and error-prone.  When
compounded with multi-branched development model, it ends up
accumulating inconsistencies over time.  Some of those inconsistencies
cause immediate problems and fixed.  Others just remain there dormant
making maintenance increasingly difficult.

To rectify the problem, this patch implements ata_port_operations
inheritance.  To allow LLDs to easily re-use their own ops tables
overriding only specific methods, this patch implements poor man's
class inheritance.  An ops table has ->inherits field which can be set
to any ops table as long as it doesn't create a loop.  When the host
is started, the inheritance chain is followed and any operation which
isn't specified is taken from the nearest ancestor which has it
specified.  This operation is called finalization and done only once
per an ops table and the LLD doesn't have to do anything special about
it other than making the ops table non-const such that libata can
update it.

libata provides four base ops tables lower drivers can inherit from -
base, sata, pmp, sff and bmdma.  To avoid overriding these ops
accidentaly, these ops are declared const and LLDs should always
inherit these instead of using them directly.

After finalization, all the ops table are identical before and after
the patch except for setting .irq_handler to ata_interrupt in drivers
which didn't use to.  The .irq_handler doesn't have any actual effect
and the field will soon be removed by later patch.

* sata_sx4 is still using old style EH and currently doesn't take
  advantage of ops inheritance.
Signed-off-by: NTejun Heo <htejun@gmail.com>

libata lets low level drivers build scsi_host_template and register it
to the SCSI layer.  This allows low level drivers high level of
flexibility but also burdens them with lots of boilerplate entries.

This patch implements SHT initializers which can be used to initialize
all the boilerplate entries in a sht.  Three variants of them are
implemented - BASE, BMDMA and NCQ - for different types of drivers.
Note that entries can be overriden by putting individual initializers
after the helper macro.

All sht tables are identical before and after this patch.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Over the time, port info, ops and sht structures developed quite a bit
of inconsistencies.  This patch updates drivers.

* Enable/disable_pm callbacks added to all ahci ops tables.

* Every driver for SFF controllers now uses ata_sff_port_start()
  instead of ata_port_start() unless the driver has custom
  implementation.

* Every driver for SFF controllers now uses ata_pci_default_filter()
  unless the driver has custom implementation.

* Removed an odd port_info->sht initialization from ata_piix.c.
  Likely a merge byproduct.

* A port which has ATA_FLAG_SATA set doesn't need to set cable_detect
  to ata_cable_sata().  Remove it from via and mv port ops.

* Some drivers had unnecessary .max_sectors initialization which is
  ignored and was missing .slave_destroy callback.  Fixed.

* Removed unnecessary sht initializations port_info's.

* Removed onsolete scsi device suspend/resume callbacks from
  pata_bf54x.

* No reason to set ata_pci_default_filter() and bmdma functions for
  PIO-only drivers.  Remove those callbacks and replace
  ata_bmdma_irq_clear with ata_noop_irq_clear.

* pata_platform sets port_start to ata_dummy_ret0.  port_start can
  just be set to NULL.

* sata_fsl supports NCQ but was missing qc_defer.  Fixed.

* pata_rb600_cf implements dummy port_start.  Removed.
Signed-off-by: NTejun Heo <htejun@gmail.com>

->irq_clear() is used to clear IRQ bit of a SFF controller and isn't
useful for drivers which don't use libata SFF HSM implementation.
However, it's a required callback and many drivers implement their own
noop version as placeholder.  This patch implements ata_noop_irq_clear
and use it to replace those custom placeholders.

Also, SFF drivers which don't support BMDMA don't need to use
ata_bmdma_irq_clear().  It becomes noop if BMDMA address isn't
initialized.  Convert them to use ata_noop_irq_clear().
Signed-off-by: NTejun Heo <htejun@gmail.com>

Some controllers can't reliably record the initial D2H FIS after SATA
link is brought online for whatever reason.  Advanced controllers
which don't have traditional TF register based interface often have
this problem as they don't really have the TF registers to update
while the controller and link are being initialized.

SKIP_D2H_BSY works around the problem by skipping the wait for device
readiness before issuing SRST, so for such controllers libata issues
SRST blindly and hopes for the best.

Now that libata defaults to hardreset, this workaround is no longer
necessary.  For controllers which have support for hardreset, SRST is
never issued by itself.  It is only issued as follow-up SRST for
device classification and PMP initialization, so there's no need to
wait for it from prereset.

Kill ATA_LFLAG_SKIP_D2H_BSY.
Signed-off-by: NTejun Heo <htejun@gmail.com>

When both soft and hard resets are available, libata preferred
softreset till now.  The logic behind it was to be softer to devices;
however, this doesn't really help much.  Rationales for the change:

* BIOS may freeze lock certain things during boot and softreset can't
  unlock those.  This by itself is okay but during operation PHY event
  or other error conditions can trigger hardreset and the device may
  end up with different configuration.

  For example, after a hardreset, previously unlockable HPA can be
  unlocked resulting in different device size and thus revalidation
  failure.  Similar condition can occur during or after resume.

* Certain ATAPI devices require hardreset to recover after certain
  error conditions.  On PATA, this is done by issuing the DEVICE RESET
  command.  On SATA, COMRESET has equivalent effect.  The problem is
  that DEVICE RESET needs its own execution protocol.

  For SFF controllers with bare TF access, it can be easily
  implemented but more advanced controllers (e.g. ahci and sata_sil24)
  require specialized implementations.  Simply using hardreset solves
  the problem nicely.

* COMRESET initialization sequence is the norm in SATA land and many
  SATA devices don't work properly if only SRST is used.  For example,
  some PMPs behave this way and libata works around by always issuing
  hardreset if the host supports PMP.

  Like the above example, libata has developed a number of mechanisms
  aiming to promote softreset to hardreset if softreset is not going
  to work.  This approach is time consuming and error prone.

  Also, note that, dependingon how you read the specs, it could be
  argued that PMP fan-out ports require COMRESET to start operation.
  In fact, all the PMPs on the market except one don't work properly
  if COMRESET is not issued to fan-out ports after PMP reset.

* COMRESET is an integral part of SATA connection and any working
  device should be able to handle COMRESET properly.  After all, it's
  the way to signal hardreset during reboot.  This is the most used
  and recommended (at least by the ahci spec) method of resetting
  devices.

So, this patch makes libata prefer hardreset over softreset by making
the following changes.

* Rename ATA_EH_RESET_MASK to ATA_EH_RESET and use it whereever
  ATA_EH_{SOFT|HARD}RESET used to be used.  ATA_EH_{SOFT|HARD}RESET is
  now only used to tell prereset whether soft or hard reset will be
  issued.

* Strip out now unneeded promote-to-hardreset logics from
  ata_eh_reset(), ata_std_prereset(), sata_pmp_std_prereset() and
  other places.
Signed-off-by: NTejun Heo <htejun@gmail.com>

In sata_fsl_probe memory is allocated but never used or deallocated.
Fixes: http://bugzilla.kernel.org/show_bug.cgi?id=10404

Thanks to Daniel Marjamäki for the bug report.
Reported-by: NDaniel Marjamäki <danielm77@spray.se>
Signed-off-by: NJohann Felix Soden <johfel@users.sourceforge.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

as prescribed in Documentation/powerpc/booting-without-of.txt.
Signed-off-by: NKim Phillips <kim.phillips@freescale.com>
Acked-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

This patch fixes build and few warnings when ATA_VERBOSE_DEBUG
is defined:

  CC      drivers/ata/sata_fsl.o
drivers/ata/sata_fsl.c: In function ‘sata_fsl_fill_sg’:
drivers/ata/sata_fsl.c:338: warning: format ‘%x’ expects type ‘unsigned int’, but argument 3 has type ‘void *’
drivers/ata/sata_fsl.c:338: warning: format ‘%x’ expects type ‘unsigned int’, but argument 4 has type ‘struct prde *’
drivers/ata/sata_fsl.c: In function ‘sata_fsl_qc_issue’:
drivers/ata/sata_fsl.c:459: error: ‘csr_base’ undeclared (first use in this function)
drivers/ata/sata_fsl.c:459: error: (Each undeclared identifier is reported only once
drivers/ata/sata_fsl.c:459: error: for each function it appears in.)
drivers/ata/sata_fsl.c: In function ‘sata_fsl_freeze’:
drivers/ata/sata_fsl.c:525: error: ‘csr_base’ undeclared (first use in this function)
make[2]: *** [drivers/ata/sata_fsl.o] Error 1
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

that provided by the block layer

ATA requires that all DMA transfers begin and end on word boundaries.
Because of this, a large amount of machinery grew up in ide to adjust
scatterlists on this basis.  However, as of 2.5, the block layer has a
dma_alignment variable which ensures both the beginning and length of a
DMA transfer are aligned on the dma_alignment boundary.  Although the
block layer does adjust the beginning of the transfer to ensure this
happens, it doesn't actually adjust the length, it merely makes sure
that space is allocated for transfers beyond the declared length.  The
upshot of this is that scatterlists may be padded to any size between
the actual length and the length adjusted to the dma_alignment safely
knowing that memory is allocated in this region.

Right at the moment, SCSI takes the default dma_aligment which is on a
512 byte boundary.  Note that this aligment only applies to transfers
coming in from user space.  However, since all kernel allocations are
automatically aligned on a minimum of 32 byte boundaries, it is safe to
adjust them in this manner as well.

tj: * Adjusting sg after padding is done in block layer.  Make libata
      set queue alignment correctly for ATAPI devices and drop broken
      sg mangling from ata_sg_setup().
    * Use request->raw_data_len for ATAPI transfer chunk size.
    * Killed qc->raw_nbytes.
    * Separated out killing qc->n_iter.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

qc->n_iter was used for libata's own sg walking before sg chaining
replaced it.  During conversion, the field and its usage in sata_fsl
were left behind.  Kill the filed and update sata_fsl.

tj: This was part of James's libata-use-block-layer-padding patch.
    Separated out by me.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Li Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

drivers/ata/sata_fsl.c: In function 'sata_fsl_fill_sg':
drivers/ata/sata_fsl.c:337: error: redeclaration of 'si' with no linkage
drivers/ata/sata_fsl.c:326: error: previous declaration of 'si' was here
Reported-by: NOlof Johansson <olof@lixom.net>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

libata used private sg iterator to handle padding sg.  Now that sg can
be chained, padding can be handled using standard sg ops.  Convert to
chained sg.

* s/qc->__sg/qc->sg/

* s/qc->pad_sgent/qc->extra_sg[]/.  Because chaining consumes one sg
  entry.  There need to be two extra sg entries.  The renaming is also
  for future addition of other extra sg entries.

* Padding setup is moved into ata_sg_setup_extra() which is organized
  in a way that future addition of other extra sg entries is easy.

* qc->orig_n_elem is unused and removed.

* qc->n_elem now contains the number of sg entries that LLDs should
  map.  qc->mapped_n_elem is added to carry the original number of
  mapped sgs for unmapping.

* The last sg of the original sg list is used to chain to extra sg
  list.  The original last sg is pointed to by qc->last_sg and the
  content is stored in qc->saved_last_sg.  It's restored during
  ata_sg_clean().

* All sg walking code has been updated.  Unnecessary assertions and
  checks for conditions the core layer already guarantees are removed.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Implement protocol tests - ata_is_atapi(), ata_is_nodata(),
ata_is_pio(), ata_is_dma(), ata_is_ncq() and ata_is_data() and use
them to replace is_atapi_taskfile() and hard coded protocol tests.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: Nashish kalra <ashish.kalra@freescale.com>
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: Nashish kalra <ashish.kalra@freescale.com>
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: Nashish kalra <ashish.kalra@freescale.com>
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Remove unneeded on-stack copy of FIS
in sata_fsl_cache_taskfile_from_d2h_fis().
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

SCRs in the driver map to the standard values found in include/linux/ata.h,
so no need for individual scr_read/scr_write case statements duplicating
the natural value.
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Powerpc uses virtual irq which has to be unmapped.
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Update the driver to use the newly added ata_link structure.
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch adds support for Freescale 3.0Gbps SATA Controller supporting
Native Command Queueing(NCQ), device hotplug, and ATAPI.  This controller
can be found on MPC8315 and MPC8378.
Signed-off-by: NAshish Kalra <ashish.kalra@freescale.com>
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>