While reading variable size descriptors (like string descriptor), some UFS
devices may report the "LENGTH" (field in "Transaction Specific fields" of
Query Response UPIU) same as what was requested in Query Request UPIU
instead of reporting the actual size of the variable size descriptor.
Although it's safe to ignore the "LENGTH" field for variable size
descriptors as we can always derive the length of the descriptor from
the descriptor header fields. Hence this change impose the length match
check only for fixed size descriptors (for which we always request the
correct size as part of Query Request UPIU).
Reviewed-by: NVenkat Gopalakrishnan <venkatg@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When sending query to the device, the index  of the failure
is additional useful information that should be printed out as it
might specify the logical unit (LU) where the error occurred.
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some of the queries might fail during init. To avoid
system failure, we add retry mechanism to issue queries
several times.
Signed-off-by: NDolev Raviv <draviv@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some UFS host controllers may think granularities of PRDT length and
offset as bytes, not double words.
Signed-off-by: NKiwoong Kim <kwmad.kim@samsung.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add a new ufshcd_state, indicats that an err handler may get to run
immediately. Use UFSHCD_STATE_ERROR here looks not literaly correct.
Signed-off-by: NZang Leigang <zangleigang@hisilicon.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some UFS host controller may need to configure some things around
hibern8 enter/exit
Signed-off-by: NKiwoong Kim <kwmad.kim@samsung.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some UFS host controller may need to configure some things before any
task management request is issued
Signed-off-by: NKiwoong Kim <kwmad.kim@samsung.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some UFS host controller may need to configure some things before any
transfer request is issued.
Signed-off-by: NKiwoong Kim <kwmad.kim@samsung.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch uses the resource-managed to add the devfreq device.  This
function will make it easy to handle the devfreq device.

- struct devfreq *devm_devfreq_add_device(struct device *dev,
				  struct devfreq_dev_profile *profile,
				  const char *governor_name,
				  void *data);
Cc: Vinayak Holikatti <vinholikatti@gmail.com>
Cc: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When we are resuming the UFS device rails in HPM mode, we are first
powering on the VCC rail while VCCQ and VCCQ2 rails still being in LPM
mode. Some UFS devices may take VCC on event as hint that host wants UFS
device to be resumed and may start drawing more power from the
VCCQ/VCCQ2 rails (while they are still in LPM mode) causing voltage drop
on these rails. This change fixes this issue by bringing VCCQ & VCCQ2
rails out of LPM before powering on VCC rail.
Reviewed-by: NVenkat Gopalakrishnan <venkatg@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Currently clock scaling is suspended only after the host and device are
put in low power mode but we should avoid clock scaling running after
UFS link is put in low power mode (hibern8). This change suspends clock
scaling before putting host/device in low power mode.
Reviewed-by: NSahitya Tummala <stummala@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If ufshcd pltfrm/pci driver's probe fails for some reason then ensure
that scsi host is released to avoid memory leak but managed memory
allocations (via devm_* calls) need not to be freed explicitly on probe
failure as memory allocated with these functions is automatically freed
on driver detach.
Reviewed-by: NSahitya Tummala <stummala@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

UFS devfreq clock scaling work may require clocks to be ON if it need to
execute some UFS commands hence it may request for clock hold before
issuing the command. But if UFS clock gating work is already running in
parallel, ungate work would end up waiting for the clock gating work to
finish and as clock gating work would also wait for the clock scaling
work to finish, we would enter in deadlock state. Here is the call trace
during this deadlock state:

Workqueue: devfreq_wq devfreq_monitor
	__switch_to
	__schedule
	schedule
	schedule_timeout
	wait_for_common
	wait_for_completion
	flush_work
	ufshcd_hold
	ufshcd_send_uic_cmd
	ufshcd_dme_get_attr
	ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div
	ufs_qcom_clk_scale_notify
	ufshcd_scale_clks
	ufshcd_devfreq_target
	update_devfreq
	devfreq_monitor
	process_one_work
	worker_thread
	kthread
	ret_from_fork

Workqueue: events ufshcd_gate_work
	__switch_to
	__schedule
	schedule
	schedule_preempt_disabled
	__mutex_lock_slowpath
	mutex_lock
	devfreq_monitor_suspend
	devfreq_simple_ondemand_handler
	devfreq_suspend_device
	ufshcd_gate_work
	process_one_work
	worker_thread
	kthread
	ret_from_fork

Workqueue: events ufshcd_ungate_work
	__switch_to
	__schedule
	schedule
	schedule_timeout
	wait_for_common
	wait_for_completion
	flush_work
	__cancel_work_timer
	cancel_delayed_work_sync
	ufshcd_ungate_work
	process_one_work
	worker_thread
	kthread
	ret_from_fork

This change fixes this deadlock by doing this in devfreq work (devfreq_wq):
Try cancelling clock gating work. If we are able to cancel gating work
or it wasn't scheduled, hold the clock reference count until scaling is
in progress. If gate work is already running in parallel, let's skip
the frequecy scaling at this time and it will be retried once next scaling
window expires.
Reviewed-by: NSahitya Tummala <stummala@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In a case where gate work is called as part of cancel work from ungate
path the clk state would be marked as REQ_CLKS_ON.  There is no point
gating the clocks and then end up turning them ON immediately in ungate
work, save time by skipping the gate work and change the clk state to
CLKS_ON as they are not turned off yet.
Signed-off-by: NVenkat Gopalakrishnan <venkatg@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The ungate work turns on the clock before it exits hibern8, if the link
was put in hibern8 during clock gating work.  There occurs a race
condition when clock scaling work calls ufshcd_hold() to make sure low
power states cannot be entered, but that returns by checking only
whether the clocks are on.  This causes the clock scaling work to issue
UIC commands when the link is in hibern8 causing failures. Make sure we
exit hibern8 state before returning from ufshcd_hold().

Callstacks for race condition:

 ufshcd_scale_gear
 ufshcd_devfreq_scale
 ufshcd_devfreq_target
 update_devfreq
 devfreq_monitor
 process_one_work
 worker_thread
 kthread
 ret_from_fork

 ufshcd_uic_hibern8_exit
 ufshcd_ungate_work
 process_one_work
 worker_thread
 kthread
 ret_from_fork
Signed-off-by: NVenkat Gopalakrishnan <venkatg@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In case the power configuration fails, skip further processing of the
probing function and return immediately. This has 2 reasons:

1. Don't allow the UFS to continue running in PWM

2. Avoid multiple calls to pm_runtime_put_sync() when not in error
   handling or power management contexts
Signed-off-by: NDov Levenglick <dovl@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

During runtime resume operation, clock scaling may get indirectly
resumed via call to ufshcd_set_dev_pwr_mode(): Start/Stop Unit command
times out and SCSI error handling ultimately calls the host reset
handler to recover, during which clock scaling is resumed.  Error case
exit path of runtime resume will disable clocks.  As clock scaling was
already resumed, it will get scheduled later on and try to access UFS
registers while clocks are disabled, resulting in unclocked register
access.
Signed-off-by: NGilad Broner <gbroner@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

According to UFS device specification, sense data can be only 18 bytes
long, this change makes the changes accordingly.
Signed-off-by: NGilad Broner <gbroner@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add a write memory barrier to make sure descriptors prepared are
actually written to memory before ringing the doorbell. We have also
added the write memory barrier after ringing the doorbell register so
that controller sees the new request immediately.
Signed-off-by: NGilad Broner <gbroner@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In this change there are a few fixes of possible NULL pointer access and
possible access to index that exceeds array boundaries.
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Vendor specific setup_clocks callback may require the clocks managed by
ufshcd driver to be ON. So if the vendor specific setup_clocks callback
is called while the required clocks are turned off, it could result into
unclocked register access.

To prevent possible unclock register access, this change adds one more
argument to setup_clocks callback to let it know whether it is called
pre/post the clock changes by core driver.
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: NKiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fix to return a negative error code from the error handling case instead
of 0, as done elsewhere in this function.
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: NKiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some devices have problems handling a Query UPIU with Data Segment
set. Only set it for WRITE DESCRIPTOR commands.

[mkp: updated patch description]
Signed-off-by: NZang Leigang <zangleigang@hisilicon.com>
Reviewed-by: NSubhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: NKiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When any UFS host controller receives a TM(Task Management) response
from a UFS device, UFS driver has been recognize like receiving a
message of "Task Management Function Complete"(00h) in all cases, so
far.  That means there is no pending task for a tag of the TM request
sent before in the UFS device.  That's because the byte offset 6 in TM
response which has been used to get a TM service response so far
represents just whether or not a TM transmission passes.

Regarding UFS spec, the correct byte offset to get TM service response
is 15, not 6.

I tested that UFS driver responds properly for the TM response from a
UFS device with an reference board with exynos8890, as follow: No
pending task -> Task Management Function Complete (00h) Pending task ->
Task Management Function Succeeded (08h)

[mkp: applied by hand]
Signed-off-by: NKiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: NHeonGwang Chu <hg.chu@samsung.com>
Tested-by: N: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

I modified a string as described in UFS spec as follow: umpcrs -> upmcrs.

[mkp: applied by hand]
Signed-off-by: NKiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When buff_ascii kmalloc failed, there is no need to call kfree, it
should return -ENOMEM directly, this patch fixes it.
Signed-off-by: NTiezhu Yang <kernelpatch@126.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add UFS 2.0 support to the UFS core driver.
Signed-off-by: NJoao Pinto <jpinto@synopsys.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NTomas Winkler <tomas.winkler@intel.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

We put the UFS device in sleep state & UFS link in hibern8 state during
runtime suspend. After this we put all the UFS rails in low power
modes immediately but it seems some devices may still draw more than
sleep current from UFS rails (especially from VCCQ rail) at-least for
500us.
To avoid this situation, this change adds 2ms delay before putting
these UFS rails in LPM mode.
Reviewed-by: NGilad Broner <gbroner@codeaurora.org>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Currently when we try to put the link in off/disabled state during
suspend, it seems link is not being kept in low power mode.
This patch fixes the issue by putting the link in hibern8 first
(so device also puts the link in low power mode) and then stop the
host controller.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Optimal values of local UniPro parameters like PA_Hibern8Time &
PA_TActivate can help reduce the hibern8 exit latency. If both host and
device supports UniPro ver1.6 or later, these parameters will be
automatically tuned during link startup itself. But if either host or
device doesn't support UniPro ver 1.6 or later, we have to manually
tune them. But to keep manual tuning logic simple, we will only do
manual tuning if local unipro version doesn't support ver1.6 or later.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

We are seeing that some devices are raising the urgent bkops exception
events even when BKOPS status doesn't indicate performace impacted or
critical. Handle these device by determining their urgent bkops status
at runtime.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Query commands have 100ms timeout and it may timeout if they are
issued in parallel to ongoing read/write SCSI commands, this change
adds the retry (max: 10) in case command timeouts.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some vendor's UFS device sends back to back NACs for the DL data frames
causing the host controller to raise the DFES error status. Sometimes
such UFS devices send back to back NAC without waiting for new
retransmitted DL frame from the host and in such cases it might be
possible the Host UniPro goes into bad state without raising the DFES
error interrupt. If this happens then all the pending commands would
timeout only after respective SW command (which is generally too
large).

This change workarounds such device behaviour like this:
- As soon as SW sees the DL NAC error, it would schedule the error
  handler
- Error handler would sleep for 50ms to see if there any fatal errors
  raised by UFS controller.
   - If there are fatal errors then SW does normal error recovery.
   - If there are no fatal errors then SW sends the NOP command to
     device to check if link is alive.
       - If NOP command times out, SW does normal error recovery
       - If NOP command succeed, skip the error handling.

If DL NAC error is seen multiple times with some vendor's UFS devices
then enable this quirk to initiate quick error recovery and also
silence related error logs to reduce spamming of kernel logs.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

UFS driver's error handler forcefully tries to clear all the pending
requests. For each pending request in the queue, it waits 1 sec for it
to get cleared. If we have multiple requests in the queue then it's
possible that we might end up waiting for those many seconds before
resetting the host. But note that resetting host would any way clear
all the pending requests from the hardware. Hence this change skips
the forceful clear of the pending requests if we are anyway going to
reset the host (for fatal errors).
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some UFS devices don't require VCCQ rail for device operations hence
this change adds support to recognize such devices and remove vote for
the unused VCCQ rail.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Currently we use the host quirks mechanism in order to
handle both device and host controller quirks.
In order to support various of UFS devices we should separate
handling the device quirks from the host controller's.
Reviewed-by: NGilad Broner <gbroner@codeaurora.org>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NRaviv Shvili <rshvili@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This change adds support to read device descriptor and string descriptor
from a UFS device
Reviewed-by: NGilad Broner <gbroner@codeaurora.org>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NRaviv Shvili <rshvili@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Sometimes due to hw issues it takes some time to the
host controller register to update. In order to verify the register
has updated, a polling is done until its value is set.

In addition the functions ufshcd_hba_stop() and
ufshcd_wait_for_register() was updated with an additional input
parameter, indicating the timeout between reads will
be done by sleeping or spinning the cpu.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NRaviv Shvili <rshvili@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

A race condition exists between request requeueing and scsi layer
error handling:
When UFS driver queuecommand returns a busy status for a request,
it will be requeued and its tag will be freed and set to -1.
At the same time it is possible that the request will timeout and
scsi layer will start error handling for it. The scsi layer reuses
the request and its tag to send error related commands to the device,
however its tag is no longer valid.
As this request was never really sent to the device, there is no
point to start error handling with the device.
Implement the scsi error handling timeout callback and bypass SCSI
error handling for request that were not actually sent to the device.
For such requests simply reset the block layer timer. Otherwise, let
SCSI layer perform the usual error handling.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NGilad Broner <gbroner@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When control reaches to Linux UFS driver during UFS boot mode, UFS host
controller interrupt status/enable registers may have left over
settings.
In order to avoid any spurious interrupts due to these left overs,
it's important to clear these interrupt status/enable registers before
enabling UFS interrupt handling.
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: NYaniv Gardi <ygardi@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>