Introduce a new "delayed error handling" mechanism in sata_mv,
to enable us to eventually deal with multiple simultaneous NCQ
failures on a single host link when a PM is present.

This involves a port flag (MV_PP_FLAG_DELAYED_EH) to prevent new
commands being queued, and a pmp bitmap to indicate which pmp links
had NCQ errors.

The new mv_pmp_error_handler() uses those values to invoke
ata_eh_analyze_ncq_error() on each failed link, prior to freezing
the port and passing control to sata_pmp_error_handler().

This is based upon a strategy suggested by Tejun.

For now, we just implement the delayed mechanism.
The next patch in this series will add the multiple-NCQ EH code
to take advantage of it.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Separate out the inner loop body of mv_host_intr()
into it's own function called mv_port_intr().

This should help maintainabilty.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Remove the unwanted reads of hc_irq_cause from mv_host_intr(),
thereby removing a bug whereby we were not always reading it when needed..
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Sigh.  Undo some earlier changes to mv_port_intr(),
so that we now read/clear SError again in all cases.

Arrange the top of the function to be as close as possible
to what we need for a later update (in this series) for ERR_DEV handling.

Fix things so that libata-eh can attempt a READ_LOG_EXT_10H
in response to a failed NCQ command, by just doing a local
mv_eh_freeze() rather than ata_port_freeze().

This will now fully handle NCQ errors much of the time,
but more fixes are needed for FBS/PMP, and for certain chip errata.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Rearrange mv_config_fbs() to more closely follow the (corrected) datasheet
recommendations for NCQ and FIS-based switching (FBS).

Also, maintain a port flag to let us know when FBS is enabled.
We will make more use of that flag later in this patch series.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Part 1 of workaround for errata "sata#25" for the 60x1 series
(the second half of this errata workaround is still in development.

Bit22 of the GPIO port has to be set "on" when in NCQ mode.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

The EDMA engine cannot tolerate a mix of NCQ/non-NCQ commands,
and cannot be used for PIO at all.  So we need to prevent libata
from trying to feed us such mixtures.

Introduce mv_qc_defer() for this purpose, and use it for all chip versions.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

When performing EH, it is recommended to wait for the EDMA engine
to empty out requests-in-progress before disabling EDMA.

Introduce code to poll the EDMA_STATUS register for idle/empty bits
before disabling EDMA.  For non-EH operation, this will normally exit
without delay, other than the register read.

A later series of patches may focus on eliminating this and various
other register reads (when possible) throughout the driver,
but for now we're focussing on solid reliablity.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Some of the GenIIe EDMA optimizations should not be used
for non-PCI (SOC) devices, and nor for certain configurations
of conventional PCI (non PCI-X, PCIe) buses.

Logic taken/simplified from that in the Marvell proprietary driver.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

More cosmetic changes; no code changes.

 -- try and improve consistency of naming.
 -- add missing _OFS to tails of register offset definitions.
 -- rename mv_setup_ifctl() to mv_setup_ifcfg(), since that's what it really does.
 -- remove/move some dead comments
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Tidy up naming of things associated with the PCI / SOC chip
"main irq cause/mask" registers, as inspired by Jeff.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Re-enable hotplug, now that the interrupt/error handling are mostly sane.
Also update the TODO list at the top.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Here it is again, minus the checkpatch.pl complaint:

Rework mv_err_intr() to leave the SError bits as-is,
so that libata-eh has a chance to see/use them.

We originally thought that clearing them here was necessary
before writing back to edma_err_cause (per the Marvell datasheets),
but we will end up reseting the chip regardless in those cases.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Continue fixing the interrupt handling logic.

Get rid of mv_intr_pio(), by using ata_sff_host_intr() for PIO..

Add a mv_unexpected_intr() catch-all for "impossible" scenarios,
where we get an interrupt that shouldn't have happened
(never seen in testing, but just in case..).

Rearrange the logic so that we always process completed
response queue entries before looking for other events,
This avoids having to re-issue commands that had already succeeded.

As part of this, we split out some duplicated functionality
into a new function, mv_get_active_qc().
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Tidy up host controller interrupt handling, by moving the weirdo
bit shifting from mv_interrupt() to mv_host_intr().

This lets us take advantage of the MV_PORT_TO_SHIFT_AND_HARDPORT() macro
from an earlier patch to greatly simplify the port numbering logic.

Also, defer reading the hc_irq_cause (one per hc) until it is
actually proven to be needed.  This may save a microsecond or
so per interrupt, on average (a later patchset will further reduce
unnecessary register reads throughout the driver).

Apart from that, we still leave the actual IRQ handling logic alone.
Subsequent patches in this series will address that.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Try and simplify handling of the request/response queues.

Maintain the cached copies of queue indexes in a fully-masked state,
rather than having each use of them have to do the masking.

Split off handling of a single crpb response into a separate function,
to reduce complexity in the main mv_process_crpb_entries() routine.

Ignore the rarely-valid error bits from the crpb status field,
as we already handle that information in mv_err_intr().

For now, preserve the rest of the original logic.
A later patch will deal with fixing that separately.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Introduce the MV_PORT_TO_SHIFT_AND_HARDPORT() macro,
to centralize/simplify various scattered bits of logic
for calculating bit shifts and the like.

Some of the places that do this get it wrong, too,
so consolidating the algorithm at one place will help
keep the code correct.

For now, we use the new macro in mv_eh_{freeze,thaw}.
A subsequent patch will re-use this in the interrupt handlers
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Ignore *all* interrupt coalescing bits on all controllers,
not just some of each.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

More cosmetic cleanups prior to the interrupt/error handling logic changes.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

sata_mv does not yet fully support hotplug (coming soon, though).
This means that the driver may not find a Silicon Image port-multiplier
when first loaded, because those devices take in exceess of 3 seconds
to sync up the SATA PHY (most devices do this in mere microseconds).

So, as a short-term interim measure, here we insert a 3-second pause
on initial driver load, once per controller board (not once per port!),
to allow the Silicon Image port-multipliers to be detected later.

This will be removed again (soon!) once hotplug is fully implemented/working.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Remove unnecessary edma init code from port_start.
This sequence gets done later on the first I/O to the port.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Add basic port-multiplier support to sata_mv.
This works in Command-based-switching mode for Gen-II chipsets,
and in FIS-based-switching mode for Gen-IIe chipsets.

Error handling remains at the primary port level for now
(works okay, but not great).  This will get fixed in a subsequent
patch series for IRQ/EH handling fixes.  There are also some
known NCQ/PMP errata to be dealt with in the near future,
once we have this basic PMP support in place.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

The System-On-Chip (SOC) core supports all of the same
features as the other recent Marvell chips,
including NCQ and IRQ coalescing.

Fix the chip_soc flags to enable these capabilities
(note that the driver currently does nothing special
for IRQ coalescing, though).
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Disable hot plug/unplug detection in sata_mv for now.
It is currently broken, and also interferes with PMP support.

This will get fixed in a subsequent patch series.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

More cosmetic cleanups to unclutter the changes needed for PMP support.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Rework and simplify sata_mv's hardreset code to take advantage of
libata improvements since it was first coded.

Also, get rid of the now unnecessary prereset, postreset, and phy_reset
functions.

This patch also paves the way for subsequent pmp support patches,
which will follow once this one passes muster.
Signed-off-by: NMark Lord <mlord@pobox.com>
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>

Fix handling of the SATA_INTERFACE_CFG register to match datasheet requirements.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Clean up uses of mv_stop_edma{_engine}() to match datasheet requirements.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Various cosmetic fixes in preparation for real code changes later on.
Signed-off-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

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>

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>

Make it possible to pass mbus_dram_target_info to the sata_mv
driver via the platform data, make the sata_mv driver program
the window registers based on this data if it is passed in, and
make the Orion platform setup code use this method instead of
programming the SATA mbus window registers by hand.
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Reviewed-by: NTzachi Perelstein <tzachi@marvell.com>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NNicolas Pitre <nico@marvell.com>

this will fix crash bug when doing rmmod to the driver, this is because the
port_stop function get called later and it could access the device's registers.
Signed-off-by: NSaeed Bishara <saeed@marvell.com>
Acked-by: NMark Lord <mlord@pobox.com>
Acked-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

this fixes crash bug as the iomap table is not valid for integrated controllers.
Signed-off-by: NSaeed Bishara <saeed@marvell.com>
Acked-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The sata_mv driver can be loaded as a platform device, as is done by
various Orion (ARM) based devices.  The driver needs to define a module
alias for the platform driver so udev will load it automatically.
Tested with Debian on a QNAP TS-209.
Signed-off-by: NMartin Michlmayr <tbm@cyrius.com>
Acked-by: NMark Lord <mlord@pobox.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>