Add generic clock initialization support for UFSHCD platform
driver. The clock info is read from device tree using standard
clock bindings. A generic max-clock-frequency-hz property is
defined to save information on maximum operating clock frequency
the h/w supports.
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: NDolev Raviv <draviv@codeaurora.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

UFS devices are powered by at most three external power supplies -
- VCC - The flash memory core power supply, 2.7V to 3.6V or 1.70V to 1.95V
- VCCQ - The controller and I/O power supply, 1.1V to 1.3V
- VCCQ2 - Secondary controller and/or I/O power supply, 1.65V to 1.95V

For some devices VCCQ or VCCQ2 are optional as they can be
generated using internal LDO inside the UFS device.

Add DT bindings for voltage regulators that can be controlled
from host driver.
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: NDolev Raviv <draviv@codeaurora.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Some vendor specific controller versions might need to configure
vendor specific - registers, clocks, voltage regulators etc. to
initialize the host controller UTP layer and Uni-Pro stack.
Provide some common initialization operations that can be used
to configure vendor specifics. The methods can be extended in
future, for example, for power mode transitions.

The operations are vendor/board specific and hence determined with
the help of compatible property in device tree.
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: NDolev Raviv <draviv@codeaurora.org>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Error handling in UFS driver is broken and resets the host controller
for fatal errors without re-initialization. Correct the fatal error
handling sequence according to UFS Host Controller Interface (HCI)
v1.1 specification.

o Processed requests which are completed w/wo error are reported to
  SCSI layer and any pending commands that are not started are aborted
  in the controller and re-queued into scsi mid-layer queue.

o Upon determining fatal error condition the host controller may hang
  forever until a reset is applied. Block SCSI layer for sending new
  requests and apply reset in a separate error handling work.

o SCSI is informed about the expected Unit-Attention exception from the
  device for the immediate command after a reset so that the SCSI layer
  take necessary steps to establish communication with the device.
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Reviewed-by: NYaniv Gardi <ygardi@codeaurora.org>
Tested-by: NDolev Raviv <draviv@codeaurora.org>
Acked-by: NVinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

As of now SCSI initiated error handling is broken because,
the reset APIs don't try to bring back the device initialized and
ready for further transfers.

In case of timeouts, the scsi error handler takes care of handling aborts
and resets. Improve the error handling in such scenario by resetting the
device and host and re-initializing them in proper manner.
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Reviewed-by: NYaniv Gardi <ygardi@codeaurora.org>
Tested-by: NDolev Raviv <draviv@codeaurora.org>
Acked-by: NVinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Currently, sending Task Management (TM) command to the card might
be broken in some scenarios as listed below:

Problem: If there are more than 8 TM commands the implementation
         returns error to the caller.
Fix:     Wait for one of the slots to be emptied and send the command.

Problem: Sometimes it is necessary for the caller to know the TM service
         response code to determine the task status.
Fix:     Propogate the service response to the caller.

Problem: If the TM command times out no proper error recovery is
         implemented.
Fix:     Clear the command in the controller door-bell register, so that
         further commands for the same slot don't fail.

Problem: While preparing the TM command descriptor, the task tag used
         should be unique across SCSI/NOP/QUERY/TM commands and not the
	 task tag of the command which the TM command is trying to manage.
Fix:     Use a unique task tag instead of task tag of SCSI command.

Problem: Since the TM command involves H/W communication, abruptly ending
         the request on kill interrupt signal might cause h/w malfunction.
Fix:     Wait for hardware completion interrupt with TASK_UNINTERRUPTIBLE
         set.
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Reviewed-by: NYaniv Gardi <ygardi@codeaurora.org>
Tested-by: NDolev Raviv <draviv@codeaurora.org>
Acked-by: NVinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Make undeclared functions static and declare exported symbols
to suppress warnings from sparse tool.
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Acked-by: NVinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Setting PA_PWRMode using DME_SET triggers the power mode
change. And then the result will be given by the HCS.UPMCRS.
This operation should be done atomically.
Signed-off-by: NSeungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Tested-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NSantosh Y <santoshsy@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Implements to support GET and SET operations of the DME.
These operations are used to configure the behavior of
the UNIPRO. Along with basic operation, {Peer/AttrSetType}
can be mixed.
Signed-off-by: NSeungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Tested-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NSantosh Y <santoshsy@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Background operations in the UFS device can be disabled by
the host to reduce the response latency of transfer requests.
Add support for enabling/disabling the background operations
during runtime suspend/resume of the device.

If the device is in critical need of BKOPS it will raise an
URGENT_BKOPS exception which should be handled by the host to
make sure the device performs as expected.

During bootup, the BKOPS is enabled in the device by default.
The disable of BKOPS is supported only when the driver supports
runtime suspend/resume operations as the runtime PM framework
provides a way to determine the device idleness and hence BKOPS
can be managed effectively. During runtime resume the BKOPS is
disabled to reduce latency and during runtime suspend the BKOPS
is enabled to allow device to carry out idle time BKOPS.

In some cases where the BKOPS is disabled during runtime resume
and due to continuous data transfers the runtime suspend is not
triggered, the BKOPS is enabled when the device raises a level-2
exception (outstanding operations - performance impact).
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: NSantosh Y <santoshsy@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Allow UFS device to complete its initialization and accept
SCSI commands by setting fDeviceInit flag. The device may take
time for this operation and hence the host should poll until
fDeviceInit flag is toggled to zero. This step is mandated by
UFS device specification for device initialization completion.
Signed-off-by: NDolev Raviv <draviv@codeaurora.org>
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: NSantosh Y <santoshsy@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

As part of device initialization sequence, sending NOP OUT UPIU and
waiting for NOP IN UPIU response is mandatory. This confirms that the
device UFS Transport (UTP) layer is functional and the host can configure
the device with further commands. Add support for sending NOP OUT UPIU to
check the device connection path and test whether the UTP layer on the
device side is functional during initialization.

A tag is acquired from the SCSI tag map space in order to send the device
management command. When the tag is acquired by internal command the scsi
command is rejected with host busy flag in order to requeue the request.
To avoid frequent collisions between internal commands and scsi commands
the device management command tag is allocated in the opposite direction
w.r.t block layer tag allocation.
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: NDolev Raviv <draviv@codeaurora.org>
Signed-off-by: NSantosh Y <santoshsy@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Link start-up requires long time with multiphase handshakes
between UFS host and device. This affects driver's probe time.
This patch let link start-up run asynchronously. Link start-up
will be executed at the end of prove separately.
Along with this change, the following is worked.

Defined completion time of uic command to avoid a permanent wait.
Added mutex to guarantee of uic command at a time.
Adapted some sequence of controller initialization after link statup
according to HCI standard.
Signed-off-by: NSeungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: NSujit Reddy Thumma <sthumma@codeaurora.org>
Tested-by: NMaya Erez <merez@codeaurora.org>
Signed-off-by: NSantosh Y <santoshsy@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

It makes interrupt setting more flexible especially
for disabling. And wrong bit mask is fixed for ver 1.0.
[17:16] is added for mask.
Signed-off-by: NSeungwon Jeon <tgih.jun@samsung.com>
Tested-by: NMaya Erez <merez@codeaurora.org>
Signed-off-by: NSantosh Y <santoshsy@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Simplify operations with hiding mmio_base.
Signed-off-by: NSeungwon Jeon <tgih.jun@samsung.com>
Tested-by: NMaya Erez <merez@codeaurora.org>
Signed-off-by: NSantosh Y <santoshsy@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This patch separates PCI code from ufshcd.c and makes it as a
core driver module and adds a new file ufshcd-pci.c as PCI glue
driver.

[jejb: strip __devinit and devexit_p()]
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NNamjae Jeon <linkinjeon@gmail.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Tested-by: NMaya Erez <merez@codeaurora.org>
Signed-off-by: NVinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: NSantosh Yaraganavi <santoshsy@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>