Dave Müller sent a diff for the pata_oldpiix that highlighted a problem
where a lot of the ATA drivers assume dma_mode == 0 means "no DMA" while
the core code uses 0xFF.

This turns out to have other consequences such as code doing >= XFER_UDMA_0
also catching 0xFF as UDMAlots. Fortunately it doesn't generally affect
set_dma_mode, although some drivers call back into their own set mode code
from other points.

Having been through the drivers I've added helpers for using_udma/using_mwdma
dma_enabled so that people don't open code ranges that may change (eg if UDMA8
appears somewhere)

Thanks to David for the initial bits
[and added fix for pata_oldpiix from and signed-off-by Dave Mueller
 <dave.mueller@gmx.ch>  -jg]
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Use correct variable, achieve desired result...

Spotted by LKML/linux-ide poster whose name I lost (apologies!)
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

SFF functions have confusing names.  Some have sff prefix, some have
bmdma, some std, some pci and some none.  Unify the naming by...

* SFF functions which are common to both BMDMA and non-BMDMA are
  prefixed with ata_sff_.

* SFF functions which are specific to BMDMA are prefixed with
  ata_bmdma_.

* SFF functions which are specific to PCI but apply to both BMDMA and
  non-BMDMA are prefixed with ata_pci_sff_.

* SFF functions which are specific to PCI and BMDMA are prefixed with
  ata_pci_bmdma_.

* Drop generic prefixes from LLD specific routines.  For example,
  bfin_std_dev_select -> bfin_dev_select.

The following renames are noteworthy.

  ata_qc_issue_prot() -> ata_sff_qc_issue()
  ata_pci_default_filter() -> ata_bmdma_mode_filter()
  ata_dev_try_classify() -> ata_sff_dev_classify()

This rename is in preparation of separating SFF support out of libata
core layer.  This patch strictly renames functions 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>

port_info->private_data is currently used for two purposes - to record
private data about the port_info or to specify host->private_data to
use when allocating ata_host.

This overloading is confusing and counter-intuitive in that
port_info->private_data becomes host->private_data instead of
port->private_data.  In addition, port_info and host don't correspond
to each other 1-to-1.  Currently, the first non-NULL
port_info->private_data is used.

This patch makes port_info->private_data just be what it is -
private_data for the port_info where LLD can jot down extra info.
libata no longer sets host->private_data to the first non-NULL
port_info->private_data, @host_priv argument is added to
ata_pci_init_one() instead.  LLDs which use ata_pci_init_one() can use
this argument to pass in pointer to host private data.  LLDs which
don't should use init-register model anyway and can initialize
host->private_data directly.

Adding @host_priv instead of using init-register model for LLDs which
use ata_pci_init_one() is suggested by Alan Cox.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>

ata_pci_init_one() is the only function which uses ops->irq_handler
and pi->sht.  Other initialization functions take the same information
as arguments.  This causes confusion and duplicate unused entries in
structures.

Make ata_pci_init_one() take sht as an argument and use ata_interrupt
implicitly.  All current users use ata_interrupt and if different irq
handler is necessary open coding ata_pci_init_one() using
ata_prepare_sff_host() and ata_activate_sff_host can be done under ten
lines including error handling and driver which requires custom
interrupt handler is likely to require custom initialization anyway.

As ata_pci_init_one() was the last user of ops->irq_handler, this
patch also kills the field.
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>

AHCI needs sorting too but this deals with the old interface
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This avoids allocating DMA buffers if not needed but at the moment is
mostly just a neatness item.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

It was always set to ata_port_disable().  Removed the hook, and replaced
the very few ap->ops->port_disable() callsites with direct calls to
ata_port_disable().
Signed-off-by: NJeff Garzik <jeff@garzik.org>

* ->irq_ack() is redundant to what the irq handler already
  performs... chk-status + irq-clear.  Furthermore, it is only
  called in one place, when screaming-irq-debugging is enabled,
  so we don't want to bother with a hook just for that.

* ata_dummy_irq_on() is only ever used in drivers that have
  no callpath reaching ->irq_on().  Remove .irq_on hook from
  those drivers, and the now-unused ata_dummy_irq_on()
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Make reset methods and related functions deal with ata_link instead of
ata_port.

* ata_do_reset()
* ata_eh_reset()
* all prereset/reset/postreset methods and related functions

This patch introduces no behavior change.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Bump the versions for drivers that were modified, but had not already
had a version number bump.
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This flag only has meaning in old-EH drivers, and these drivers have
already been converted to the new EH.  Remove.
Signed-off-by: NJeff Garzik <jeff@garzik.org>

From AMD.
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The intention of using port_mask in SFF init helpers was to eventually
support exoctic configurations such as combination of legacy and
native port on the same controller.  This never became actually
necessary and the related code always has been subtly broken one way
or the other.  Now that new init model is in place, there is no reason
to make common helpers capable of handling all corner cases.  Exotic
cases can simply dealt within LLDs as necessary.

This patch removes port_mask handling in SFF init helpers.  SFF init
helpers don't take n_ports argument and interpret it into port_mask
anymore.  All information is carried via port_info.  n_ports argument
is dropped and always two ports are allocated.  LLD can tell SFF to
skip certain port by marking it dummy.  Note that SFF code has been
treating unuvailable ports this way for a long time until recent
breakage fix from Linus and is consistent with how other drivers
handle with unavailable ports.

This fixes 1-port legacy host handling still broken after the recent
native mode fix and simplifies SFF init logic.  The following changes
are made...

* ata_pci_init_native_host() and ata_init_legacy_host() both now try
  to initialized whatever they can and mark failed ports dummy.  They
  return 0 if any port is successfully initialized.

* ata_pci_prepare_native_host() and ata_pci_init_one() now doesn't
  take n_ports argument.  All info should be specified via port_info
  array.  Always two ports are allocated.

* ata_pci_init_bmdma() exported to be used by LLDs in exotic cases.

* port_info handling in all LLDs are standardized - all port_info
  arrays are const stack variable named ppi.  Unless the second port
  is different from the first, its port_info is specified as NULL
  (tells libata that it's identical to the last non-NULL port_info).

* pata_hpt37x/hpt3x2n: don't modify static variable directly.  Make an
  on-stack copy instead as ata_piix does.

* pata_uli: It has 4 ports instead of 2.  Don't use
  ata_pci_prepare_native_host().  Allocate the host explicitly and use
  init helpers.  It's simple enough.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Reimplement suspend/resume support using sdev->manage_start_stop.

* Device suspend/resume is now SCSI layer's responsibility and the
  code is simplified a lot.

* DPM is dropped.  This also simplifies code a lot.  Suspend/resume
  status is port-wide now.

* ata_scsi_device_suspend/resume() and ata_dev_ready() removed.

* Resume now has to wait for disk to spin up before proceeding.  I
  couldn't find easy way out as libata is in EH waiting for the
  disk to be ready and sd is waiting for EH to complete to issue
  START_STOP.

* sdev->manage_start_stop is set to 1 in ata_scsi_slave_config().
  This fixes spindown on shutdown and suspend-to-disk.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add @deadline to prereset and reset methods and make them honor it.
ata_wait_ready() which directly takes @deadline is implemented to be
used as the wait function.  This patch is in preparation for EH timing
improvements.

* ata_wait_ready() never does busy sleep.  It's only used from EH and
  no wait in EH is that urgent.  This function also prints 'be
  patient' message automatically after 5 secs of waiting if more than
  3 secs is remaining till deadline.

* ata_bus_post_reset() now fails with error code if any of its wait
  fails.  This is important because earlier reset tries will have
  shorter timeout than the spec requires.  If a device fails to
  respond before the short timeout, reset should be retried with
  longer timeout rather than silently ignoring the device.

  There are three behavior differences.

  1. Timeout is applied to both devices at once, not separately.  This
     is more consistent with what the spec says.

  2. When a device passes devchk but fails to become ready before
     deadline.  Previouly, post_reset would just succeed and let
     device classification remove the device.  New code fails the
     reset thus causing reset retry.  After a few times, EH will give
     up disabling the port.

  3. When slave device passes devchk but fails to become accessible
     (TF-wise) after reset.  Original code disables dev1 after 30s
     timeout and continues as if the device doesn't exist, while the
     patched code fails reset.  When this happens, new code fails
     reset on whole port rather than proceeding with only the primary
     device.

  If the failing device is suffering transient problems, new code
  retries reset which is a better behavior.  If the failing device is
  actually broken, the net effect is identical to it, but not to the
  other device sharing the channel.  In the previous code, reset would
  have succeeded after 30s thus detecting the working one.  In the new
  code, reset fails and whole port gets disabled.  IMO, it's a
  pathological case anyway (broken device sharing bus with working
  one) and doesn't really matter.

* ata_bus_softreset() is changed to return error code from
  ata_bus_post_reset().  It used to return 0 unconditionally.

* Spin up waiting is to be removed and not converted to honor
  deadline.

* To be on the safe side, deadline is set to 40s for the time being.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add missing #ifdef CONFIG_PM conditionals around all PM related parts
in libata LLDs.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch is against each libata driver.

Two IRQ calls are added in ata_port_operations.
- irq_on() is used to enable interrupts.
- irq_ack() is used to acknowledge a device interrupt.

In most drivers, ata_irq_on() and ata_irq_ack() are used for
irq_on and irq_ack respectively.

In some drivers (ex: ahci, sata_sil24) which cannot use them
as is, ata_dummy_irq_on() and ata_dummy_irq_ack() are used.
Signed-off-by: NKou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: NAkira Iguchi <akira2.iguchi@toshiba.co.jp>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Convert libata core layer and LLDs to use iomap.

* managed iomap is used.  Pointer to pcim_iomap_table() is cached at
  host->iomap and used through out LLDs.  This basically replaces
  host->mmio_base.

* if possible, pcim_iomap_regions() is used

Most iomap operation conversions are taken from Jeff Garzik
<jgarzik@pobox.com>'s iomap branch.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Update libata LLDs to use devres.  Core layer is already converted to
support managed LLDs.  This patch simplifies initialization and fixes
many resource related bugs in init failure and detach path.  For
example, all converted drivers now handle ata_device_add() failure
gracefully without excessive resource rollback code.

As most resources are released automatically on driver detach, many
drivers don't need or can do with much simpler ->{port|host}_stop().
In general, stop callbacks are need iff port or host needs to be given
commands to shut it down.  Note that freezing is enough in many cases
and ports are automatically frozen before being detached.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

sht->max_sectors is overrided unconditionally in ->slave_configure.
There's no reason to set it to any value.
Signed-off-by: NTejun Heo <htejun@gmail.com>

This patch adds the suspend/resume callbacks for drivers which don't need
any additional help (beyond the pci resume quirk patch I posted earlier
anyway). Also bring version numbers back inline with master copies.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Many LLDs are missing sht->slave_destroy.  The method is mandatory to
support device warm unplugging (echo 1 > /sys/.../delete).  Without
it, libata might access released scsi device.
Signed-off-by: NTejun Heo <htejun@gmail.com>

* Use PCI_VDEVICE() macro
* const-ify pci_device_id table
* standardize list terminator as "{ }"
* convert spaces to tab in pci_driver struct (Alan-ism)
* various minor whitespace cleanups
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The PATA driver set got converted to the new error handling setup, but
the old hooks were accidentally left in place.  Now, removed.
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This removes the layering violation where drivers have to fiddle
directly with EH flags. Instead we now recognize -ENOENT means "no port"
and do the handling in the core code.

This also removes an instance of a call to disable the port, and an
identical printk from each driver doing this. Even better - future rule
changes will be in one place only.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The vast majority of drivers and changes are from Alan Cox.  Albert Lee
contributed and maintains pata_pdc2027x.  Adrian Bunk, Andrew Morton,
and Tejun Heo contributed various minor fixes and updates.
Signed-off-by: NJeff Garzik <jeff@garzik.org>