Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
All drivers use the implementation for ramping the queue up and down, so
instead of overloading the change_queue_depth method call the
implementation diretly if the driver opts into it by setting the
track_queue_depth flag in the host template.
Note that a few drivers validated the new queue depth in their
change_queue_depth method, but as we never go over the queue depth
set during slave_configure or the sysfs file this isn't nessecary
and can safely be removed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Venkatesh Srinivas <venkateshs@google.com>
This patch fixes newly introduced static checker warning in
ufshcd_parse_clock_info, introduced by UFS power management series.
Warning:
drivers/scsi/ufs/ufshcd-pltfrm.c:138 ufshcd_parse_clock_info()
warn: passing devm_ allocated variable to kfree. 'clkfreq'
To fix it we remove the kfree(clkfreq) statement.
In addition we removed the redundant goto label.
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Reviewed-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This patch fixes newly introduced static checker warning in
__ufshcd_setup_clocks, introduced by UFS power management series.
Warning:
drivers/scsi/ufs/ufshcd.c:4474 __ufshcd_setup_clocks()
warn: we tested 'ret' before and it was 'false'
To fix it we remove the (!ret) from the condition.
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Reviewed-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This patch fixes newly introduced sparse warning in
ufshcd_system_suspend, introduced by UFS power management series.
Sparse warning:
drivers/scsi/ufs/ufshcd.c:5118 ufshcd_system_suspend()
error: we previously assumed 'hba' could be null (see line 5089)
To fix it, we return 0 in case HBA is not initialized or is
not powered.
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Reviewed-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
After link start-up power mode will always be PWM G1. This is not
reflected in the pwr_info struct which will keep the previous values.
Since ufshcd_change_power_mode() tries to avoid unnecessary power mode
change if the requested power mode and current power mode are same,
power mode change won't execute again after driver initialization.
This patch solves the problem by setting pwr_info to PWM G1 after link
start-up.
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Reviewed-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
UFS driver adds three well known LUs in the initialization, but those
reference counts are not decremented, so it makes ufshcd module
impossible to unload.
This fixes it by putting scsi_device_put() in the initalization, and in
order to protect concurrent access to hba->sdev_ufs_device (UFS Device
W-LU) from manual delete, increment the reference count while requesting
device power mode setting.
The rest of W-LUs (hba->sdev_boot and hba->sdev_rpmb) are not directly
used from driver, so these references in struct ufs_hba are removed.
Signed-off-by: Akinobu Mita <mita@fixstars.com>
Reviewed-by: Maya Erez <merez@codeaurora.org>
Reviewed-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
ufs never looks at the tag type, so there is no need to set it either.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Now that we also get proper values in cmd->request->tag for untagged
commands, there is no need to force tagged_supported to on in drivers
that need host-wide tags.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Remove the tagged argument from scsi_adjust_queue_depth, and just let it
handle the queue depth. For most drivers those two are fairly separate,
given that most modern drivers don't care about the SCSI "tagged" status
of a command at all, and many old drivers allow queuing of multiple
untagged commands in the driver.
Instead we start out with the ->simple_tags flag set before calling
->slave_configure, which is how all drivers actually looking at
->simple_tags except for one worke anyway. The one other case looks
broken, but I've kept the behavior as-is for now.
Except for that we only change ->simple_tags from the ->change_queue_type,
and when rejecting a tag message in a single driver, so keeping this
churn out of scsi_adjust_queue_depth is a clear win.
Now that the usage of scsi_adjust_queue_depth is more obvious we can
also remove all the trivial instances in ->slave_alloc or ->slave_configure
that just set it to the cmd_per_lun default.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Allow a driver to ask for block layer tags by setting .use_blk_tags in the
host template, in which case it will always see a valid value in
request->tag, similar to the behavior when using blk-mq. This means even
SCSI "untagged" commands will now have a tag, which is especially useful
when using a host-wide tag map.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Open-code scsi_print_result in sd.c, and cleanup logging to
not print duplicate informations.
Also remove the call to scsi_show_result() in ufshcd.c
to be consistent with other callers of scsi_execute().
With that we can remove scsi_show_result in constants.c
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
We should be using the standard dev_printk() variants for
sense code printing.
[hch: remove __scsi_print_sense call in xen-scsiback, Acked by Juergen]
[hch: folded bracing fix from Dan Carpenter]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
- Adding some of the definitions missing in unipro.h, including power
enumeration.
- Read Modify Write Line helper function
- Indication for the type of suspend
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add capability to control the auto bkops during suspend.
If host explicitly enables the auto bkops (background operation) on device
then only device would perform the bkops on its own. If auto bkops is not
enabled explicitly and if the device reaches to state where it must do
background operation, device would raise the urgent bkops exception event
to host and then host will enable the auto bkops on device. This patch
adds the option to choose whether auto bkops should be enabled during
runtime suspend or not. Since we don't want to keep the device active to
perform the non critical bkops, host will enable urgent bkops only.
Keep auto-bkops enabled after resume if urgent bkops needed.
If device bkops status shows that its in critical need of executing
background operations, host should allow the device to continue doing
background operations.
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The clocks for UFS device will be managed by generic DVFS (Dynamic
Voltage and Frequency Scaling) framework within kernel. This devfreq
framework works with different governors to scale the clocks. By default,
UFS devices uses simple_ondemand governor which scales the clocks up if
the load is more than upthreshold and scales down if the load is less than
downthreshold.
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The UFS controller clocks can be gated after certain period of
inactivity, which is typically less than runtime suspend timeout.
In addition to clocks the link will also be put into Hibern8 mode
to save more power.
The clock gating can be turned on by enabling the capability
UFSHCD_CAP_CLK_GATING. To enable entering into Hibern8 mode as part of
clock gating, set the capability UFSHCD_CAP_HIBERN8_WITH_CLK_GATING.
The tracing events for clock gating can be enabled through debugfs as:
echo 1 > /sys/kernel/debug/tracing/events/ufs/ufshcd_clk_gating/enable
cat /sys/kernel/debug/tracing/trace_pipe
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Sometimes, the device shall report its maximum power and speed
capabilities, but we might not wish to configure it to use those
maximum capabilities.
This change adds support for the vendor specific host driver to
implement power change notify callback.
To enable configuring different power modes (number of lanes,
gear number and fast/slow modes) it is necessary to split the
configuration stage from the stage that reads the device max power mode.
In addition, it is not required to read the configuration more than
once, thus the configuration is stored after reading it once.
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This patch adds support for UFS device and UniPro link power management
during runtime/system PM.
Main idea is to define multiple UFS low power levels based on UFS device
and UFS link power states. This would allow any specific platform or pci
driver to choose the best suited low power level during runtime and
system suspend based on their power goals.
bkops handlig:
To put the UFS device in sleep state when bkops is disabled, first query
the bkops status from the device and enable bkops on device only if
device needs time to perform the bkops.
START_STOP handling:
Before sending START_STOP_UNIT to the device well-known logical unit
(w-lun) to make sure that the device w-lun unit attention condition is
cleared.
Write protection:
UFS device specification allows LUs to be write protected, either
permanently or power on write protected. If any LU is power on write
protected and if the card is power cycled (by powering off VCCQ and/or
VCC rails), LU's write protect status would be lost. So this means those
LUs can be written now. To ensures that UFS device is power cycled only
if the power on protect is not set for any of the LUs, check if power on
write protect is set and if device is in sleep/power-off state & link in
inactive state (Hibern8 or OFF state).
If none of the Logical Units on UFS device is power on write protected
then all UFS device power rails (VCC, VCCQ & VCCQ2) can be turned off if
UFS device is in power-off state and UFS link is in OFF state. But current
implementation would disable all device power rails even if UFS link is
not in OFF state.
Low power mode:
If UFS link is in OFF state then UFS host controller can be power collapsed
to avoid leakage current from it. Note that if UFS host controller is power
collapsed, full UFS reinitialization will be required on resume to
re-establish the link between host and device.
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
UFS device may have standard LUs and LUN id could be from 0x00 to 0x7F.
UFS device specification use "Peripheral Device Addressing Format"
(SCSI SAM-5) for standard LUs.
UFS device may also have the Well Known LUs (also referred as W-LU) which
again could be from 0x00 to 0x7F. For W-LUs, UFS device specification only
allows the "Extended Addressing Format" (SCSI SAM-5) which means the W-LUNs
would start from 0xC100 onwards.
This means max. LUN number reported from UFS device could be 0xC17F hence
this patch advertise the "max_lun" as 0xC17F which will allow SCSI mid
layer to detect the W-LUs as well.
But once the W-LUs are detected, UFSHCD driver may get the commands with
SCSI LUN id upto 0xC17F but UPIU LUN id field is only 8-bit wide so it
requires the mapping of SCSI LUN id to UPIU LUN id. This patch also add
support for this mapping.
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
UFS device specification requires the UFS devices to support 4 well known
logical units:
"REPORT_LUNS" (address: 01h)
"UFS Device" (address: 50h)
"RPMB" (address: 44h)
"BOOT" (address: 30h)
UFS device's power management needs to be controlled by "POWER CONDITION"
field of SSU (START STOP UNIT) command. But this "power condition" field
will take effect only when its sent to "UFS device" well known logical unit
hence we require the scsi_device instance to represent this logical unit in
order for the UFS host driver to send the SSU command for power management.
We also require the scsi_device instance for "RPMB" (Replay Protected
Memory Block) LU so user space process can control this LU. User space may
also want to have access to BOOT LU.
This patch adds the scsi device instances for each of all well known LUs
(except "REPORT LUNS" LU).
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The maximum power consumption in active is determined by bActiveICCLevel.
The configuration is done by reading max current supported by the
regulators connected to VCC, VCCQ and VCCQ2 rails on the boards, and
reading the current consumption levels from the device for each rails
(vcc/vccq/vccq2) using power descriptor.
We configure the bActiveICCLevel attribute, with the max value that
correspond to the minimum-of(VCC-current-level,VCCQ-current-level,
VCCQ2-current-level).
In order to minimize resume latency, pre-fetch icc levels and reference
clock during initialization and avoid reading them each link startup
during resume.
Signed-off-by: Raviv Shvili <rshvili@codeaurora.org>
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In ->hce_enable_notify() callback the vendor specific initialization
may carry out additional DME configuration using UIC commands and
hence the UIC command completion interrupt enable bit should be set
before the post reset notification.
Add retries if the link-startup fails. This is required since due to
hardware timing issues, the Uni-Pro link-startup might fail. The UFS
HCI recovery procedure contradicts the Uni-Pro sequence. The UFS HCI
specifies to resend DME_LINKSTARTUP command after IS.ULLS (link-lost
interrupt) is received. The Uni-Pro specifies that if link-startup
fails the link is in "down" state. The link-lost is indicated to the
DME user only when the link is up. Hence, the UFS HCI recovery procedure
of waiting for IS.ULLS and retrying link-startup may not work properly.
At the end, if detection fails, power off (disable clocks, regulators,
phy) if the UFS device detection fails. This saves power while UFS device
is not embedded into the system.
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Currently reading query descriptor is more tightened to each
descriptor type. This patch generalize the approach and allows
reading any parameter from any query descriptor.
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add the support for voting of the regulator powering the
host controller logic.
Signed-off-by: Raviv Shvili <rshvili@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph 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: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph 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: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
We should prefer `struct pci_device_id` over `DEFINE_PCI_DEVICE_TABLE` to
meet kernel coding style guidelines. This issue was reported by checkpatch.
A simplified version of the semantic patch that makes this change is as
follows (http://coccinelle.lip6.fr/):
// <smpl>
@@
identifier i;
declarer name DEFINE_PCI_DEVICE_TABLE;
initializer z;
@@
- DEFINE_PCI_DEVICE_TABLE(i)
+ const struct pci_device_id i[]
= z;
// </smpl>
[bhelgaas: add semantic patch]
Signed-off-by: Benoit Taine <benoit.taine@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Fix many warnings with incorrect endian assumptions
which makes the code unportable to new architectures.
The UFS specification defines the byte order as big-endian
for UPIU structure and little-endian for the host controller
transfer/task management descriptors.
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
If the controller doesn't support 64-bit addressing mode, it must not
set the DMA mask to 64-bit. But it's unconditionally trying to set to
64-bit without checking 64-bit addressing support in the controller
capabilities.
It was correctly checked before commit 3b1d05807a
("[SCSI] ufs: Segregate PCI Specific Code"), this aims to restores
the correct behaviour.
To achieve this in a generic way, firstly we should push down the DMA
mask setting routine ufshcd_set_dma_mask() from PCI glue driver to core
driver in order to do it for both PCI glue driver and Platform glue
driver. Secondly, we should change pci_ DMA mapping API to dma_ DMA
mapping API because core driver is independent of glue drivers.
Signed-off-by: Akinobu Mita <mita@fixstars.com>
Acked-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The data byte count field of PRDT indicates the length of data block
which is a segment of data transfer for SCSI commands. The value of
this field shall have Dword granularity and the the maximum of length
is 256KB.
This adjusts dma pad mask and max segment size to the above-mentioned
PRDT limitations.
Signed-off-by: Akinobu Mita <mita@fixstars.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Tested-by: Dolev Raviv <draviv@codeaurora.org>
Acked-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
UFS 1.1 specification does not support MAINTENANCE IN(0xA3) SCSI
command and hence it doesn't support REPORT SUPPORTED OPERATION CODES
as well.
Change-Id: Ic09c5b46b2511b1c28db478023c32b898ac69e6d
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In interrupt context, after reading and comparing the UTRLDBR to
hba->outstanding_request and before resetting the interrupt aggregation,
there might be completion of another transfer request (TR). Such TRs might
get stuck, pending, until the next interrupt is generated (if any).
Changing the sequence of resetting the interrupt aggregation first and
then reading UTRLDBR status, will assure that completed TRs won't get
stuck pending.
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Some UFS devices may expose bLUQueueDepth field as zero indicating
that the queue depth depends on the number of resources available
for LUN at a particular instant to handle the outstanding transfer
requests. Currently, when response for SCSI command is TASK_FULL
the LLD decrements the queue depth but fails to increment when the
resources are available. The scsi mid-layer handles the change in
queue depth heuristically and offers simple interface with
->change_queue_depth.
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Acked-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Some of the UFS devices may support different number of commands
that can be queued per LU. At the current implementation,
SW configure each of the UFS devices LU's according to the
controller capability.
In this patch the queue depth available per LU is read and updated in
the LU's SW structure.
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Raviv Shvili <rshvili@codeaurora.org>
Acked-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Check query response status before copying the response.
Add descriptor query response size check, before copying it to buffer.
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Raviv Shvili <rshvili@codeaurora.org>
Acked-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Introduces the API for sending queries with descriptors.
A descriptor is a block or page of parameters that describe the device.
The descriptors are classified into types and can range in size
from 2 bytes through 255 bytes.
All descriptors have a length value as their first element, and a type
identification element as their second byte.
All descriptors are readable and some may be write once.
They are accessed using their type, index and selector.
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Raviv Shvili <rshvili@codeaurora.org>
Acked-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: Christoph 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: Sujit Reddy Thumma <sthumma@codeaurora.org>
Reviewed-by: Yaniv Gardi <ygardi@codeaurora.org>
Tested-by: Dolev Raviv <draviv@codeaurora.org>
Acked-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: Christoph 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: Sujit Reddy Thumma <sthumma@codeaurora.org>
Reviewed-by: Yaniv Gardi <ygardi@codeaurora.org>
Tested-by: Dolev Raviv <draviv@codeaurora.org>
Acked-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
There is a possible race condition in the hardware when the abort
command is issued to terminate the ongoing SCSI command as described
below:
- A bit in the door-bell register is set in the controller for a
new SCSI command.
- In some rare situations, before controller get a chance to issue
the command to the device, the software issued an abort command.
- If the device recieves abort command first then it returns success
because the command itself is not present.
- Now if the controller commits the command to device it will be
processed.
- Software thinks that command is aborted and proceed while still
the device is processing it.
- The software, controller and device may go out of sync because of
this race condition.
To avoid this, query task presence in the device before sending abort
task command so that after the abort operation, the command is guaranteed
to be non-existent in both controller and the device.
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Reviewed-by: Yaniv Gardi <ygardi@codeaurora.org>
Tested-by: Dolev Raviv <draviv@codeaurora.org>
Acked-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: Christoph 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: Sujit Reddy Thumma <sthumma@codeaurora.org>
Reviewed-by: Yaniv Gardi <ygardi@codeaurora.org>
Tested-by: Dolev Raviv <draviv@codeaurora.org>
Acked-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Fix many warnings with incorrect endian assumptions
which makes the code unportable to new architectures.
The UFS specification defines the byte order as big-endian
for UPIU structure and little-endian for the host controller
transfer/task management descriptors.
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Acked-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull trivial tree updates from Jiri Kosina:
"Usual earth-shaking, news-breaking, rocket science pile from
trivial.git"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
doc: usb: Fix typo in Documentation/usb/gadget_configs.txt
doc: add missing files to timers/00-INDEX
timekeeping: Fix some trivial typos in comments
mm: Fix some trivial typos in comments
irq: Fix some trivial typos in comments
NUMA: fix typos in Kconfig help text
mm: update 00-INDEX
doc: Documentation/DMA-attributes.txt fix typo
DRM: comment: `halve' -> `half'
Docs: Kconfig: `devlopers' -> `developers'
doc: typo on word accounting in kprobes.c in mutliple architectures
treewide: fix "usefull" typo
treewide: fix "distingush" typo
mm/Kconfig: Grammar s/an/a/
kexec: Typo s/the/then/
Documentation/kvm: Update cpuid documentation for steal time and pv eoi
treewide: Fix common typo in "identify"
__page_to_pfn: Fix typo in comment
Correct some typos for word frequency
clk: fixed-factor: Fix a trivial typo
...
Since commit 0998d06310
(device-core: Ensure drvdata = NULL when no driver is bound),
the driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Cc: James Bottomley <JBottomley@parallels.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
UIC attributes can be set with using DME_SET command for
power mode change. For configuration the link capability
attributes are used, which is updated after successful
link startup.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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: Seungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Tested-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James 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: Seungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Tested-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
IACTH(Interrupt aggregation counter threshold) value is allowed
up to 0x1F and current setting value is the maximum.
This value is related with NUTRS(max:0x20) of HCI's capability.
Considering HCI controller doesn't support the maximum, IACTH
setting should be adjusted with possible value.
For that, existing 'ufshcd_config_int_aggr' is split into two part
[reset, configure].
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Tested-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Unlike 'GOOD' and 'CHECK CONDITION', other status values in
Response UPIU may or may not contain sense data. That is returning
sense data isn't obvious. So, in this case the Data Segment Length
field should be checked. If a non-zero value, it means that UPIU
has Sense Data in the Data Segment area.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Tested-by: Yaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
devm_ioremap_resource does sanity checks on the given resource. No need to
duplicate this in the driver.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
There is a error message within devm_ioremap_resource
already, so remove the dev_err call to avoid redundant
error message.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
scsi_remove_host() sends SYNCHRONIZE CACHE commands for write cache
enabled scsi disk devices. So stopping controller working shouldn't
be done before scsi_remove_host().
Signed-off-by: Akinobu Mita <mita@fixstars.com>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
When removing the UFS driver, disable_irq() is called and the IRQ is
not enabled again. Unfortunately, the IRQ is requested with IRQF_SHARED
and it can be shared among several devices. So disabling the IRQ in
this way is just breaking other devices which are sharing the IRQ.
Signed-off-by: Akinobu Mita <mita@fixstars.com>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Before commit 2953f850c3 ("[SCSI] ufs:
use devres functions for ufshcd"), UFSHCI register was ioremapped by
each glue-driver (ufshcd-pltfrm and ufshcd-pci) during probing and it
was iounmapped by core-driver during removing driver. The commit
converted ufshcd-pltfrm to use devres functions, but it didn't convert
ufshcd-pci.
Therefore, the change causes ufshcd-pci driver not to iounmap UFSHCI
register region during removing driver. This fixes it by converting
ufshcd-pci to use devres functions.
Signed-off-by: Akinobu Mita <mita@fixstars.com>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Add runtime PM helpers to suspend/resume UFS controller at runtime.
Enable runtime PM by default for pci and platform drivers as the
initialized hardware can suspend if it is not used after bootup.
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James 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: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James 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: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James 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: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Changing the device coherent dma mask to the value that currently set
has no effect.
Signed-off-by: Akinobu Mita <mita@fixstars.com>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
In UIC error interrupt handling, it checks if UIC data link layer error
code indicates PA_INIT_ERROR in order to determine whether a fatal error
handling is needed or not.
But the code tries to read UIC data link layer error code from wrong
REG_UIC_ERROR_CODE_PHY_ADAPTER_LAYER, it should be
REG_UIC_ERROR_CODE_DATA_LINK_LAYER.
Signed-off-by: Akinobu Mita <mita@fixstars.com>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
of_match_table member in struct device_driver must be terminated by
empty slot as a sentinel.
Signed-off-by: Akinobu Mita <mita@fixstars.com>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This patch replaces normal calls for resource allocation with devm_*()
derivative functions. It makes resource freeing simpler.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
The response UPIU length should be in DWORD and not in bytes.
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James 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: Seungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Tested-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
There is no need to check the version to clear
the interrupt status. And the order is changed
prior to actual handling.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Tested-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James 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: Seungwon Jeon <tgih.jun@samsung.com>
Tested-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
If NO_DMA=y:
drivers/built-in.o: In function `ufshcd_transfer_req_compl':
drivers/scsi/ufs/ufshcd.c:1182: undefined reference to `scsi_dma_unmap'
drivers/built-in.o: In function `ufshcd_map_sg':
drivers/scsi/ufs/ufshcd.c:377: undefined reference to `scsi_dma_map'
drivers/built-in.o: In function `ufshcd_do_reset':
drivers/scsi/ufs/ufshcd.c:912: undefined reference to `scsi_dma_unmap'
drivers/built-in.o: In function `ufshcd_memory_alloc':
drivers/scsi/ufs/ufshcd.c:565: undefined reference to `dma_alloc_coherent'
drivers/built-in.o: In function `ufshcd_free_hba_memory':
drivers/scsi/ufs/ufshcd.c:185: undefined reference to `dma_free_coherent'
drivers/scsi/ufs/ufshcd.c:192: undefined reference to `dma_free_coherent'
drivers/scsi/ufs/ufshcd.c:199: undefined reference to `dma_free_coherent'
drivers/scsi/ufs/ufshcd.c:185: undefined reference to `dma_free_coherent'
drivers/scsi/ufs/ufshcd.c:192: undefined reference to `dma_free_coherent'
drivers/built-in.o:drivers/scsi/ufs/ufshcd.c:199: more undefined references to `dma_free_coherent' follow
drivers/built-in.o: In function `ufshcd_abort':
drivers/scsi/ufs/ufshcd.c:1498: undefined reference to `scsi_dma_unmap'
drivers/built-in.o: In function `ufshcd_device_reset':
drivers/scsi/ufs/ufshcd.c:1436: undefined reference to `scsi_dma_unmap'
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Commit 0998d06310 (device-core: Ensure drvdata = NULL when no
driver is bound) removes the need to set driver data field to
NULL.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This patch corrects the expected data transfer size of the
command UPIU. The current implementation of cmd->transfersize
is wrong as it probably equal to sector size. With this
implementation the transfer size is updated correctly
Reported-by: KOBAYASHI Yoshitake <yoshitake.kobayashi@toshiba.co.jp>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Tested-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Santosh Yaraganavi <santoshsy@gmail.com>
Signed-off-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: James 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: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Tested-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: Santosh Yaraganavi <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This patch segregates the PCI specific code in ufshcd.c to make it
ready for splitting into core ufs driver and PCI glue driver. Also
copyright header modification to remove extra warranty disclaim.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Tested-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: Santosh Yaraganavi <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
CONFIG_HOTPLUG is going away as an option. As a result, the __dev*
markings need to be removed.
This change removes the use of __devinit, __devexit_p, __devinitdata,
__devinitconst, and __devexit from these drivers.
Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Adam Radford <linuxraid@lsi.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the UFS host driver has returned incorrect values for SUCCESS
and FAILED. Fix it to return the correct value to the upper layer.
Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Acked-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: Venkatraman S <svenkatr@ti.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Otherwise it counter intuitively returns 0 if device is present.
Signed-off-by: Venkatraman S <svenkatr@ti.com>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Acked-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Use macro module_pci_driver and get rid of boilerplate code. No
functional changes.
Signed-off-by: Venkatraman S <svenkatr@ti.com>
Acked-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Avoid dereferencing a NULL pointer if scsi_host_alloc is failed.
Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
UTP Transfer request list base registers UTRLBA and UTRLBAU
must be assigned, lower-32 and upper-32 bits of UTRLD list
physical base addresses respectively.
Currently UTRLBAU is being assigned lower-32 bits of UTRLD
physical base address. This will cause an issue with
controllers that can support 64-bit addressing.
This patch correctly assigns upper-32 bits of UTRLD physical
base address to UTRLBAU.
Reported-by: Rene De Jong <rene.dejong@arm.com>
Signed-off-by: Santosh Yaraganavi <santoshsy@gmail.com>
Reviewed-by: Vinayak Holikatti <vinholikatti@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
While interpreting the result of UTP task completion status,
by using boolean &&, the evaluation would fail when the
UPIU_TASK_MANAGEMENT_FUNC_SUCCEEDED was received.
Either UPIU_TASK_MANAGEMENT_FUNC_COMPL or
UPIU_TASK_MANAGEMENT_FUNC_SUCCEEDED should be
considered as a success result.
Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Venkatraman S <svenkatr@ti.com>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Acked-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This patch adds support for Universal Flash Storage(UFS)
host controllers. The UFS host controller driver
includes host controller initialization method.
The Initialization process involves following steps:
- Initiate UFS Host Controller initialization process by writing
to Host controller enable register
- Configure UFS Host controller registers with host memory space
datastructure offsets.
- Unipro link startup procedure
- Check for connected device
- Configure UFS host controller to process requests
- Enable required interrupts
- Configure interrupt aggregation
[jejb: fix warnings in 32 bit compile]
Signed-off-by: Santosh Yaraganavi <santoshsy@gmail.com>
Signed-off-by: Vinayak Holikatti <vinholikatti@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@linaro.org>
Reviewed-by: Vishak G <vishak.g@samsung.com>
Reviewed-by: Girish K S <girish.shivananjappa@linaro.org>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Christoph Hellwig