"No task timeout timer reduced from 20 to 2 This timer controls how
long the SCU hardware will hold open the TX side of the connection
before sending a DONE.  The timer allows the hardware to attempt to
optimize the DONE/CLOSE behavior to allow for new COMMAND IU to be
posted.  In practice closing the connection quicker is better."
Signed-off-by: NMarcin Tomczak <marcin.tomczak@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

v1.3 allows the attenuation of the attached cables to be specified to
the driver in terms of 'short', 'medium', and 'long' (see probe_roms.h).
These settings (per phy) are retrieved from the platform oem-parameters
(BIOS rom) or via a module parameter override.
Reviewed-by: NJiangbi Liu <jiangbi.liu@intel.com>
Signed-off-by: NJeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

v1.1 allows finer grained tuning of the SSC (spread-spectrum-clocking)
settings for SAS and SATA.  See notes in probe_roms.h
Signed-off-by: NDave Jiang <dave.jiang@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

C1 silicon requires updates to the phy tuning recipe and also support
for user provided cable selects (per-phy) for short, medium, and long
cables.  Default to 'short' awaiting support for selecting the cable via
oem parameters.
Reviewed-by: NJiangbi Liu <jiangbi.liu@intel.com>
Signed-off-by: NMarcin Tomczak <marcin.tomczak@intel.com>
Signed-off-by: NJeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Before updating the code to support the latest platform updates and
silicon revision cleanup some of the long deref chains.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Fixes bug where max_concurr_spinup oem parameter should be
overriden by max_concurr_spinup user parameter. Override should
happen only when max_concurr_spinup user parameter is specified
in command line (greater than 0). Also this fix shortens variables
representing max_conxurr_spinup for oem and user parameters.
Signed-off-by: NAndrzej Jakowski <andrzej.jakowski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Basic support to initialize the gpio unit, accept an incomming
SAS_GPIO_REG_TX_GP bitstream, and translate it to the ODx.n fields in
the hardware registers.  If register indexes outside the supported range
are specified in the SMP frame we simply accept the write and return how
many registers (SFF-8485) were written (libsas reports this as residue
in the request).
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Hardware only increments the put pointer on event types >= 4.  Do not
increment the get pointer for event type 3.
Reported-by: NKapil Karkra <kapil.karkra@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Hardware allows both an outstanding number commands and a timeout value
(whichever occurs first) as a gate to the next interrupt generation.  This
scheme at completion time looks at the remaining number of outstanding tasks
and sets the timeout to maximize small transaction operation.  If transactions
are large (take more than a few 10s of microseconds to complete) then
performance is not interrupt processing bound, so the small timeouts this
scheme generates are overridden by the time it takes for a completion to
arrive.
Tested-by: NDave Jiang <dave.jiang@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Perform checking per-pci device (even though all systems will only have
1 pci device in this generation), and delete support for silicon that
does not report a proper revision (i.e. A0).
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Does not need its own file.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Most of these simple dereference macros are longer than their open coded
equivalent.  Deleting enum sci_controller_mode is thrown in for good
measure.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

The distinction between scic_sds_ scic_ and sci_ are no longer relevant
so just unify the prefixes on sci_.  The distinction between isci_ and
sci_ is historically significant, and useful for comparing the old
'core' to the current Linux driver. 'sci_' represents the former core as
well as the routines that are closer to the hardware and protocol than
their 'isci_' brethren. sci == sas controller interface.

Also unwind the 'sds1' out of the parameter structs.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Remove the distinction between these two implementations and unify on
isci_host (local instances named ihost).  Hmmm, we had two
'oem_parameters' instances, one was unused... nice.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Remove the distinction between these two implementations and unify on
isci_remote_device (local instances named idev).
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Remove the distinction between these two implementations and unify on
isci_port (local instances named iport).  The duplicate '->owning_port' and
'->isci_port' in both isci_phy and isci_remote_device will be fixed in a later
patch... this is just the straightforward rename/unification.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

They are one in the same object so remove the distinction.  The near
duplicate fields (owning_port, and isci_port) will be cleaned up
after the scic_sds_port isci_port unification.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

They are one in the same object so remove the distinction.  The near
duplicate fields (owning_controller, and isci_host) will be cleaned up
after the scic_sds_contoller isci_host unification.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

the dma_pool interface is optimized for object_size << page_size which
is not the case with isci_request objects and the dma_pool routines show
up in the top of the profile.

The old io_request_table which tracked whether tci slots were in-flight
or not is replaced with an IREQ_ACTIVE flag per request.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

The tci_pool tracks our outstanding command slots which are also the 'index'
portion of our tags.  Grabbing the tag early in ->lldd_execute_task let's us
drop the isci_host_can_queue() and ->was_tag_assigned_by_user infrastructure.
->was_tag_assigned_by_user required the task context to be duplicated in
request-local buffer.  With the tci established early we can build the
task_context directly into its final location and skip a memcpy.

With the task context buffer at a known address at request construction we
have the opportunity/obligation to also fix sgl handling.  This rework feels
like it belongs in another patch but the sgl handling and task_context are too
intertwined.
1/ fix the 'ab' pair embedded in the task context to point to the 'cd' pair in
   the task context (previously we were prematurely linking to the staging
   buffer).
2/ fix the broken iteration of pio sgls that assumes all sgls are relative to
   the request, and does a dangerous looking reverse lookup of physical
   address to virtual address.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Now that "stopping/stopped" are one in the same and signalled by a NULL device
pointer the rest of the device status infrastructure can be removed (->status
and ->state_lock).  The "not ready for i/o state" is replaced with a state
flag, and is evaluated under scic_lock so that we don't see transients from
taking the device reference to submitting the i/o.

This also fixes a potential leakage of can_queue slots in the rare case that
SAS_TASK_ABORTED is set at submission.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

We have unsafe references to remote devices that are notified to
disappear at lldd_dev_gone.  In order to clean this up we need a single
canonical source for device lookups and stable references once a lookup
succeeds.  Towards that end guarantee that domain_device.lldd_dev is
NULL as soon as we start the process of stopping a device.  Any code
path that wants to safely lookup a remote device must do so through
task->dev->lldd_dev (isci_lookup_device()).

For in-flight references outside of scic_lock we need reference counting
to ensure that the device is not recycled before we are done with it.
Simplify device back references to just scic_sds_request.target_device
which is now the only permissible internal reference that is maintained
relative to the reference count.

There were two occasions where we wanted new i/o's to be treated as
SAS_TASK_UNDELIVERED but where the domain_dev->lldd_dev link is still
intact.  Introduce a 'gone' flag to prevent i/o while waiting for libsas
to take action on the port down event.

One 'core' leftover is that we currently call
scic_remote_device_destruct() from isci_remote_device_deconstruct()
which is called when the 'core' says the device is stopped.  It would be
more natural for the final put to trigger
isci_remote_device_deconstruct() but this implementation is deferred as
it requires other changes.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Every single i/o or event completion incurs a test and branch to see if
the cycle bit changed.  For power-of-2 queue sizes the cycle bit can be
read directly from the rollover of the queue pointer.

Likely premature optimization, but the hidden if() and hidden
assignments / side-effects in the macros were already asking to be
cleaned up.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

A tag is a 16 bit number where the upper four bits is a sequence number
and the remainder is the task context index (tci).  Sanitize the macro
names and shave 256-bytes out of scic_sds_controller by reducing the size of
io_request_sequence.

scic_sds_io_tag_construct --> ISCI_TAG
scic_sds_io_tag_get_sequence --> ISCI_TAG_SEQ
scic_sds_io_tag_get_index() --> ISCI_TAG_TCI
scic_sds_io_sequence_increment() [delete / open code]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

The circ_buf macros are ~6% faster, as measured by perf, because they take
advantage of power-of-two math assumptions i.e. no test and branch for
rollover. Their semantics are clearer than the hidden side effects in pool.h
(like sci_pool_get() which hides an assignment).
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

The old 'core' had aspirations of running in severely memory constrained
environments like bios option-rom, it's not needed for Linux and gets in
the way of other cleanups (like unifying/reducing the number of structure
members in scic_sds_controller/isci_host).

This also fixes a theoretical bug in that the driver would blindly override
the silicon advertised limits for number of ports, task contexts, and remote
node contexts.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

C0 silicon updates the pci revision id and requires new AFE parameters
for phy signal integrity.  Support for previous silicon revisions is
deprecated (it's also broken for the theoretical case of multiple
controllers at different silicon revisions, all the more reason to get
it removed as soon as possible)
Signed-off-by: NAdam Gruchala <adam.gruchala@intel.com>
[fixed up deprecated silicon support]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Additional state machine cleanups:

 o Remove static functions sci_state_machine_exit_state() and
   sci_state_machine_enter_state()
 o Combines sci_base_state_machine_construct() and
   sci_base_state_machine_start() into a single function,
   sci_init_sm()
 o Remove sci_base_state_machine_stop() which is unused.
 o Kill state_machine.[ch]
Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
[fixed too large to inline functions]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

This cleans up several areas of the state machine mechanism:

 o Rename sci_base_state_machine_change_state to sci_change_state
 o Remove sci_base_state_machine_get_state function
 o Rename 'state_machine' struct member to 'sm' in client structs
 o Shorten the name of request states
 o Shorten state machine state names as follows:
        SCI_BASE_CONTROLLER_STATE_xxx to SCIC_xxx
        SCI_BASE_PHY_STATE_xxx to SCI_PHY_xxx
        SCIC_SDS_PHY_STARTING_SUBSTATE_xxx to SCI_PHY_SUB_xxx
        SCI_BASE_PORT_STATE_xxx to SCI_PORT_xxx and
        SCIC_SDS_PORT_READY_SUBSTATE_xxx to SCI_PORT_SUB_xxx
        SCI_BASE_REMOTE_DEVICE_STATE_xxx to SCI_DEV_xxx
        SCIC_SDS_STP_REMOTE_DEVICE_READY_SUBSTATE_xxx to SCI_STP_DEV_xxx
        SCIC_SDS_SMP_REMOTE_DEVICE_READY_SUBSTATE_xxx to SCI_SMP_DEV_xxx
        SCIC_SDS_REMOTE_NODE_CONTEXT_xxx_STATE to SCI_RNC_xxx
Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: NDave Jiang <dave.jiang@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Delete code which is no longer used.
Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Convert the sata_timeout_timer in the scic_sds_phy struct to
use a struct sci_timer
Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
[squashed collateral cleanups]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Rather than preallocating a list of timers and doling them out at runtime,
embed a struct timerlist in each object that needs one.  A struct sci_timer
interface is introduced to manage the timer cancellation semantics which
currently need to guarantee the timer is cancelled while holding
spin_lock(ihost->scic_lock).  Since the timeout functions also need to acquire
the lock it currently prevents the driver from using del_timer_sync() for
runtime cancellations.

del_timer_sync() is used however before the objects go out of scope.
Signed-off-by: NEdmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Now that any given object type only has one state_machine we can use
container_of() to get back to the given state machine owner.
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Implement the stop handlers directly in scic_sds_port_stop()
Reported-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NPiotr Sawicki <piotr.sawicki@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

remove the handler from the port state handler table and implement the
logic directly in scic_sds_port_start().
Signed-off-by: NPiotr Sawicki <piotr.sawicki@intel.com>
[remove a level of indirection]
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

While cleaning up the driver it is very tempting to convert scic_sds_get_*
macros to their open coded equivalent.  They are all just pointer dereferences
*except* scic_sds_phy_get_port() which returns NULL if the phy is assigned to
the dummy port.  Clarify this by renaming it to phy_get_non_dummy_port().
Signed-off-by: NDan Williams <dan.j.williams@intel.com>