Commit Graph

642 Commits

Author SHA1 Message Date
Stanley Chu
71957b6112 scsi: ufs: ufs-mediatek: Fix build warnings with make W=1
Fix build warnings with make W=1 as below,

1.
>> drivers/scsi/ufs/ufs-mediatek.c:116:22: warning: format '%d' expects
>> argument of type 'int', but argument 4 has type 'long int'

2.
  CC [M]  drivers/scsi/ufs/ufs-mediatek.o
../drivers/scsi/ufs/ufs-mediatek.c:749: error: Cannot parse struct or union!

/** is used specifically with kernel-doc tool.
As a quick fix by removing dubious /** in the comment block of
struct ufs_hba_variant_ops ufs_hba_mtk_vops.

Link: https://lore.kernel.org/r/20200910013756.11385-1-stanley.chu@mediatek.com
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-09-09 22:08:46 -04:00
Stanley Chu
e0f9f86262 scsi: ufs: ufs-mediatek: Add host reset mechanism
Add host reset mechanism to try to recover host-side errors during recovery
flow.

Link: https://lore.kernel.org/r/20200908064507.30774-5-stanley.chu@mediatek.com
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-09-08 22:49:55 -04:00
Stanley Chu
9a9ddb8a3a scsi: ufs: ufs-mediatek: Fix flag of unipro low-power mode
Forcibly leave UniPro low-power mode if UIC commands failed.  This makes
hba_enable_delay_us as correct (default) value for re-enabling the host.

At the same time, change type of parameter "lpm" in function
ufs_mtk_unipro_set_pm() to "bool".

Link: https://lore.kernel.org/r/20200908064507.30774-4-stanley.chu@mediatek.com
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-09-08 22:49:54 -04:00
Stanley Chu
a3e40b80dc scsi: ufs: ufs-mediatek: Fix HOST_PA_TACTIVATE quirk
Simply add HOST_PA_TACTIVATE quirk back since it was incorrectly removed
before.

Link: https://lore.kernel.org/r/20200908064507.30774-3-stanley.chu@mediatek.com
Fixes: 47d054580a ("scsi: ufs-mediatek: fix HOST_PA_TACTIVATE quirk for Samsung UFS Devices")
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-09-08 22:49:54 -04:00
Stanley Chu
30a90782c1 scsi: ufs: ufs-mediatek: Eliminate error message for unbound mphy
Some MediaTek platforms does not have to bind MPHY so users shall not see
any unnecessary logs. Simply remove logs for this case.

Link: https://lore.kernel.org/r/20200908064507.30774-2-stanley.chu@mediatek.com
Fixes: fc4983018f ("scsi: ufs-mediatek: Allow unbound mphy")
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-09-08 22:49:53 -04:00
Bao D. Nguyen
499f7a9660 scsi: ufshcd: Allow specifying an Auto-Hibernate Timer value of zero
Setting the Auto-Hibernate Timer to zero is a valid setting which indicates
the Auto-Hibernate feature being disabled. Correctly support this setting.

In addition, when the timer value is queried from sysfs, read from the host
controller's register and return that value instead of using the RAM value.

Link: https://lore.kernel.org/r/b141cfcd7998b8933635828b56fbb64f8ad4d175.1598661071.git.nguyenb@codeaurora.org
Acked-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bao D. Nguyen <nguyenb@codeaurora.org>
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-09-08 21:26:15 -04:00
Can Guo
2355b66ed2 scsi: ufs: Handle LINERESET indication in err handler
PA Layer issues a LINERESET to the PHY at the recovery step in the Power
Mode change operation. If it happens during auto or manual hibern8 enter,
even if hibern8 enter succeeds, UFS power mode shall be set to PWM-G1 mode
and kept in that mode after exit from hibern8, leading to bad performance.
Handle the LINERESET in the eh_work by restoring power mode to HS mode
after all pending reqs and tasks are cleared from doorbell.

Link: https://lore.kernel.org/r/1598321228-21093-3-git-send-email-cang@codeaurora.org
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-09-02 22:49:07 -04:00
Can Guo
307348f6ab scsi: ufs: Abort tasks before clearing them from doorbell
To recover non-fatal errors, no full reset is required, err_handler only
clears those pending TRs/TMRs so that SCSI layer can re-issue them. In
current err_handler, TRs are directly cleared from UFS host's doorbell but
not aborted from device side. However, according to the UFSHCI JEDEC spec,
the host software shall use UTP Transfer Request List Clear Register to
clear a task from UFS host's doorbell only when a UTP Transfer Request is
expected to not be completed, e.g. when the host software receives a
“FUNCTION COMPLETE” Task Management response which means a Transfer Request
was aborted. To follow the UFSHCI JEDEC spec, in err_handler, abort one TR
before clearing it from doorbell.

Link: https://lore.kernel.org/r/1598321228-21093-2-git-send-email-cang@codeaurora.org
Acked-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-09-02 22:49:06 -04:00
Eric Biggers
cc770ce34a scsi: ufs: Make ufshcd_print_trs() consider UFSHCD_QUIRK_PRDT_BYTE_GRAN
Fix ufshcd_print_trs() to consider UFSHCD_QUIRK_PRDT_BYTE_GRAN when using
utp_transfer_req_desc::prd_table_length, so that it doesn't treat the
number of bytes as the number of entries.

Originally from Kiwoong Kim
(https://lkml.kernel.org/r/20200218233115.8185-1-kwmad.kim@samsung.com).

Link: https://lore.kernel.org/r/20200826021040.152148-1-ebiggers@kernel.org
Fixes: 26f968d7de ("scsi: ufs: Introduce UFSHCD_QUIRK_PRDT_BYTE_GRAN quirk")
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-09-01 22:09:51 -04:00
Kiwoong Kim
7973b8ac66 scsi: ufs: exynos: Enable UFSHCI_QUIRK_SKIP_MANUAL_WB_FLUSH_CTRL
For Exynos, flush during hibern8 is sufficient. Manual flush will cause an
increase in power usage.

Link: https://lore.kernel.org/r/ef94af8f273316d50d7f50a0cac9c7be9b9316a1.1598319701.git.kwmad.kim@samsung.com
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-31 22:10:43 -04:00
Kiwoong Kim
5df6f2def5 scsi: ufs: Introduce skipping manual flush for Write Booster
We have two knobs to control flush for write booster,
fWriteBoosterBufferFlushDuringHibernate and fWriteBoosterBufferFlushEn.

Some vendors use only fWriteBoosterBufferFlushDuringHibernate because this
can reportedly cover most scenarios. Also, there have been some reports
that flush by fWriteBoosterBufferFlushEn could lead to increased power
consumption thanks to unexpected internal operations. Consequently, we need
a way to enable or disable fWriteBoosterEn operations. Add quirk to bypass
manual flush.

Link: https://lore.kernel.org/r/ffdb0eda30515809f0ad9ee936b26917ee9b4593.1598319701.git.kwmad.kim@samsung.com
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-31 22:10:43 -04:00
Andy Teng
460d74a091 scsi: ufs: ufs-mediatek: Modify the minimum RX/TX lane count to 2
MediaTek UFS host now supports 2 lanes. Modify the lane count to 2.

This modification shall not impact old 1-lane host because
PA_CONNECTEDRXDATALANES and PA_CONNECTEDTXDATALANES will limit the target
lanes properly during power mode change. So we could relax the limitation
in ufs_dev_params.

Link: https://lore.kernel.org/r/20200819084340.7021-1-stanley.chu@mediatek.com
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Andy Teng <andy.teng@mediatek.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-20 21:59:34 -04:00
Can Guo
50807f22c8 scsi: ufs: Remove an unpaired ufshcd_scsi_unblock_requests() in err_handler()
Commit 5586dd8ea2 ("scsi: ufs: Fix a race condition between error handler
and runtime PM ops") moves the ufshcd_scsi_block_requests() inside
err_handler() but forgets to remove the ufshcd_scsi_unblock_requests() in
the early return path. Correct the mistake.

Link: https://lore.kernel.org/r/1597798958-24322-1-git-send-email-cang@codeaurora.org
Fixes: 5586dd8ea2 ("scsi: ufs: Fix a race condition between error handler and runtime PM ops")
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Reviewed-by: Hongwu Su<hongwus@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-20 21:56:25 -04:00
Kiwoong Kim
29707fab58 scsi: ufs: Change fDeviceInit busy wait
Currently, the UFS driver busy waits for fDeviceInit to be cleared. Provide
an upper bound and sleep between attempts instead of busy waiting.

Link: https://lore.kernel.org/r/1597053747-75171-1-git-send-email-kwmad.kim@samsung.com
Tested-by: Kiwoong Kim <kwmad.kim@samsung.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-20 21:53:42 -04:00
Bean Huo
b000862579 scsi: ufs: Remove several redundant goto statements
Link: https://lore.kernel.org/r/20200814095034.20709-3-huobean@gmail.com
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-20 21:41:52 -04:00
Bean Huo
f273c54bb7 scsi: ufs: Change ufshcd_comp_devman_upiu() to ufshcd_compose_devman_upiu()
ufshcd_comp_devman_upiu() was poorly named leading people to think it was a
completion function. Rename it to ufshcd_compose_devman_upiu().

Link: https://lore.kernel.org/r/20200814095034.20709-2-huobean@gmail.com
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Acked-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-20 21:41:52 -04:00
Sai Prakash Ranjan
68bdb3db6c scsi: ufs-qcom: Remove unused MSM bus scaling APIs
MSM bus scaling has moved on to use interconnect framework and downstream
bus scaling APIs like msm_bus_scale*() do not exist anymore in the
kernel. Currently they are guarded by a config which also does not exist
and hence there are no build failures reported. Remove these unused
interfaces as they are currently no-ops and the scaling support that may be
added in future will use interconnect API.

Link: https://lore.kernel.org/r/20200804161033.15586-1-saiprakash.ranjan@codeaurora.org
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-20 21:41:51 -04:00
Can Guo
8bb2dde069 scsi: ufs: Properly release resources if a task is aborted successfully
In current UFS task abort hook, namely ufshcd_abort(), if one task is
aborted successfully, clk_gating.active_reqs held by this task is not
decreased, which makes clk_gating.active_reqs stay above zero forever, thus
clock gating would never happen. Instead of releasing resources of one task
"manually", use the existing func __ufshcd_transfer_req_compl().  This
change also eliminates a possible race of scsi_dma_unmap() from the real
completion in IRQ handler path.

Link: https://lore.kernel.org/r/1596975355-39813-10-git-send-email-cang@codeaurora.org
Fixes: 1ab27c9cf8 ("ufs: Add support for clock gating")
CC: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-20 21:41:25 -04:00
Can Guo
5586dd8ea2 scsi: ufs: Fix a race condition between error handler and runtime PM ops
The current IRQ handler blocks SCSI requests before scheduling eh_work,
when error handler calls pm_runtime_get_sync, if ufshcd_suspend/resume
sends a SCSI cmd, most likely the SSU cmd, since SCSI requests are blocked,
pm_runtime_get_sync() will never return because ufshcd_suspend/resume is
blocked by the SCSI cmd.

 - In queuecommand path, hba->ufshcd_state check and ufshcd_send_command
   should stay under the same spin lock. This is to make sure that no more
   commands leak into doorbell after hba->ufshcd_state is changed.

 - Don't block SCSI requests before error handler starts to run, let error
   handler block SCSI requests when it is ready to start error recovery.

 - Don't let SCSI layer keep requeuing the SCSI cmds sent from HBA runtime
   PM ops, let them pass or fail them. Let them pass if eh_work is
   scheduled due to non-fatal errors. Fail them if eh_work is scheduled due
   to fatal errors, otherwise the cmds may eventually time out since UFS is
   in bad state, which gets error handler blocked for too long. If we fail
   the SCSI cmds sent from HBA runtime PM ops, HBA runtime PM ops fails
   too, but it does not hurt since error handler can recover HBA runtime PM
   error.

Link: https://lore.kernel.org/r/1596975355-39813-9-git-send-email-cang@codeaurora.org
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-17 20:54:56 -04:00
Can Guo
c3be8d1ee1 scsi: ufs: Move dumps in IRQ handler to error handler
Performing dumps in the IRQ handler causes system stability issues. Move
dumps to the error handler and only print basic host registers here.

Link: https://lore.kernel.org/r/1596975355-39813-8-git-send-email-cang@codeaurora.org
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-17 20:54:55 -04:00
Can Guo
c72e79c0ad scsi: ufs: Recover HBA runtime PM error in error handler
The current error handler can not recover HBA runtime PM error if
ufshcd_suspend/resume has failed due to UFS errors, e.g. hibern8 enter/exit
error or SSU cmd error. When this happens, error handler may fail
performing a full reset and restore because error handler always assumes
that power, IRQs and clocks are ready after pm_runtime_get_sync returns,
but actually they are not if ufshcd_resume fails[1].

If ufschd_suspend/resume fails due to UFS errors, runtime PM framework
saves the error value to dev.power.runtime_error. After that, HBA dev
runtime suspend/resume would not be invoked anymore unless runtime_error is
cleared[2].

In case of ufshcd_suspend/resume fails due to UFS errors, for scenario [1],
error handler cannot assume anything of pm_runtime_get_sync, meaning error
handler should explicitly turn ON powers, IRQs and clocks again. To get the
HBA runtime PM work as regard for scenario [2], error handler can clear the
runtime_error by calling pm_runtime_set_active() if full reset and restore
succeeds. And, more important, if pm_runtime_set_active() returns no error,
which means runtime_error has been cleared, we also need to resume those
scsi devices under HBA in case any of them has failed to be resumed due to
HBA runtime resume failure. This is to unblock blk_queue_enter in case
there are bios waiting inside it.

Link: https://lore.kernel.org/r/1596975355-39813-7-git-send-email-cang@codeaurora.org
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-17 20:54:54 -04:00
Can Guo
4db7a23605 scsi: ufs: Fix concurrency of error handler and other error recovery paths
Error recovery can be invoked from multiple code paths, including hibern8
enter/exit (from ufshcd_link_recovery), ufshcd_eh_host_reset_handler() and
eh_work scheduled from IRQ context. Ultimately, these paths are all trying
to invoke ufshcd_reset_and_restore() in either a synchronous or
asynchronous manner. This causes problems:

 - If link recovery happens during ungate work, ufshcd_hold() would be
   called recursively. Although commit 53c12d0ef6 ("scsi: ufs: fix error
   recovery after the hibern8 exit failure") fixed a deadlock due to
   recursive calls of ufshcd_hold() by adding a check of eh_in_progress
   into ufshcd_hold, this check allows eh_work to run in parallel while
   link recovery is running.

 - Similar concurrency can also happen when error recovery is invoked from
   ufshcd_eh_host_reset_handler and ufshcd_link_recovery.

 - Concurrency can even happen between eh_works. eh_work, currently queued
   on system_wq, is allowed to have multiple instances running in parallel,
   but we don't have proper protection for that.

If any of above concurrency scenarios happen, error recovery would fail and
lead ufs device and host into bad states. To fix the concurrency problem,
this change queues eh_work on a single threaded workqueue and removes link
recovery calls from the hibern8 enter/exit path. In addition, make use of
eh_work in eh_host_reset_handler instead of calling
ufshcd_reset_and_restore. This unifies the UFS error recovery mechanism.

According to the UFSHCI JEDEC spec, hibern8 enter/exit error occurs when
the link is broken. This essentially applies to any power mode change
operations (since they all use PACP_PWR cmds in UniPro layer). So, if a
power mode change operation (including AH8 enter/exit) fails, mark link
state as UIC_LINK_BROKEN_STATE and schedule the eh_work.  In this case,
error handler needs to do a full reset and restore to recover the link back
to active. Before the link state is recovered to active,
ufshcd_uic_pwr_ctrl simply returns -ENOLINK to avoid more errors.

Link: https://lore.kernel.org/r/1596975355-39813-6-git-send-email-cang@codeaurora.org
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-17 20:54:54 -04:00
Can Guo
3f8af60447 scsi: ufs: Add some debug information to ufshcd_print_host_state()
Information about the last interrupt status and timestamp is helpful when
debugging system stability issues (IRQ starvation, for instance). Add this
information to ufshcd_print_host_state() output.

In addition, UFS device information such as model name and firmware version
also comes in handy during debugging. This is printed as well.

Link: https://lore.kernel.org/r/1596975355-39813-5-git-send-email-cang@codeaurora.org
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Hongwu Su <hongwus@codeaurora.org>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-17 20:54:53 -04:00
Can Guo
423cc66b51 scsi: ufs-qcom: Remove testbus dump in ufs_qcom_dump_dbg_regs
Dumping testbus registers outputs a lot of information and can cause
stability issues. Remove the dump code.

Link: https://lore.kernel.org/r/1596975355-39813-4-git-send-email-cang@codeaurora.org
Reviewed-by: Hongwu Su <hongwus@codeaurora.org>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-17 20:54:52 -04:00
Can Guo
89dd87acd4 scsi: ufs: ufs-qcom: Fix race conditions caused by ufs_qcom_testbus_config()
If ufs_qcom_dump_dbg_regs() calls ufs_qcom_testbus_config() from
ufshcd_suspend/resume and/or clk gate/ungate context, pm_runtime_get_sync()
and ufshcd_hold() will cause a race condition. Fix this by removing the
unnecessary calls of pm_runtime_get_sync() and ufshcd_hold().

Link: https://lore.kernel.org/r/1596975355-39813-3-git-send-email-cang@codeaurora.org
Reviewed-by: Hongwu Su <hongwus@codeaurora.org>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-17 20:54:51 -04:00
Can Guo
2dec9475a4 scsi: ufs: Add checks before setting clk-gating states
Clock gating can be turned on/off selectively which means the associated
state information is only correct if the feature is enabled. This change
makes sure that we only look at state of clk-gating if it is enabled.

Link: https://lore.kernel.org/r/1596975355-39813-2-git-send-email-cang@codeaurora.org
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Hongwu Su <hongwus@codeaurora.org>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-08-17 20:54:50 -04:00
Linus Torvalds
dfdf16ecfd SCSI misc on 20200806
This series consists of the usual driver updates (ufs, qla2xxx, tcmu,
 lpfc, hpsa, zfcp, scsi_debug) and minor bug fixes.  We also have a
 huge docbook fix update like most other subsystems and no major update
 to the core (the few non trivial updates are either minor fixes or
 removing an unused feature [scsi_sdb_cache]).
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This consists of the usual driver updates (ufs, qla2xxx, tcmu, lpfc,
  hpsa, zfcp, scsi_debug) and minor bug fixes.

  We also have a huge docbook fix update like most other subsystems and
  no major update to the core (the few non trivial updates are either
  minor fixes or removing an unused feature [scsi_sdb_cache])"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (307 commits)
  scsi: scsi_transport_srp: Sanitize scsi_target_block/unblock sequences
  scsi: ufs-mediatek: Apply DELAY_AFTER_LPM quirk to Micron devices
  scsi: ufs: Introduce device quirk "DELAY_AFTER_LPM"
  scsi: virtio-scsi: Correctly handle the case where all LUNs are unplugged
  scsi: scsi_debug: Implement tur_ms_to_ready parameter
  scsi: scsi_debug: Fix request sense
  scsi: lpfc: Fix typo in comment for ULP
  scsi: ufs-mediatek: Prevent LPM operation on undeclared VCC
  scsi: iscsi: Do not put host in iscsi_set_flashnode_param()
  scsi: hpsa: Correct ctrl queue depth
  scsi: target: tcmu: Make TMR notification optional
  scsi: target: tcmu: Implement tmr_notify callback
  scsi: target: tcmu: Fix and simplify timeout handling
  scsi: target: tcmu: Factor out new helper ring_insert_padding
  scsi: target: tcmu: Do not queue aborted commands
  scsi: target: tcmu: Use priv pointer in se_cmd
  scsi: target: Add tmr_notify backend function
  scsi: target: Modify core_tmr_abort_task()
  scsi: target: iscsi: Fix inconsistent debug message
  scsi: target: iscsi: Fix login error when receiving
  ...
2020-08-06 16:50:07 -07:00
Stanley Chu
d61fa5bc3e scsi: ufs-mediatek: Apply DELAY_AFTER_LPM quirk to Micron devices
Micron UFS devices require DELAY_AFTER_LPM device quirk in MediaTek
platforms.

Link: https://lore.kernel.org/r/20200729051840.31318-3-stanley.chu@mediatek.com
Acked-by: Avri Altman <Avri.Altman@wdc.com>
Reviewed-by: Andy Teng <andy.teng@mediatek.com>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-30 21:11:24 -04:00
Stanley Chu
c4df6eed97 scsi: ufs: Introduce device quirk "DELAY_AFTER_LPM"
Some UFS devices require delay after VCC power rail is turned off.
Introduce a device quirk "DELAY_AFTER_LPM" to add 5ms delay after VCC
power-off during suspend flow.

Link: https://lore.kernel.org/r/20200729051840.31318-2-stanley.chu@mediatek.com
Reviewed-by: Andy Teng <andy.teng@mediatek.com>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Can Guo <cang@codeaurora.org>
Acked-by: Avri Altman <Avri.Altman@wdc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-30 21:10:29 -04:00
Stanley Chu
0255b1e3d8 scsi: ufs-mediatek: Prevent LPM operation on undeclared VCC
In some platforms, VCC regulator may not be declared in device tree to keep
itself "always-on". In this case, hba->vreg_info.vcc is NULL and shall not
be operated during any flow.

Prevent possible NULL hba->vreg_info.vcc access in LPM mode by checking
if it is valid first.

Link: https://lore.kernel.org/r/20200724141627.20094-1-stanley.chu@mediatek.com
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-28 22:59:57 -04:00
Lee Jones
b44cc4a40b scsi: ufs: ufs-exynos: Demote seemingly unintentional kerneldoc header
This is the only use of kerneldoc in the source file and no descriptions
are provided.

Fixes the following W=1 kernel build warning(s):

In file included from  drivers/scsi/ufs/ufs-exynos.c:23:
 drivers/scsi/ufs/ufs-exynos.c:234: warning: Function parameter or member 'ufs' not described in 'exynos_ufs_auto_ctrl_hcc'
 drivers/scsi/ufs/ufs-exynos.c:234: warning: Function parameter or member 'en' not described in 'exynos_ufs_auto_ctrl_hcc'

Link: https://lore.kernel.org/r/20200723122446.1329773-7-lee.jones@linaro.org
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: Avri Altman <avri.altman@wdc.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Seungwon Jeon <essuuj@gmail.com>
Cc: linux-samsung-soc@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-24 22:31:55 -04:00
Lee Jones
bc5b681614 scsi: ufs: ufs-qcom: Demote nonconformant kerneldoc headers
Fixes the following W=1 kernel build warning(s):

 drivers/scsi/ufs/ufs-qcom.c:253: warning: Function parameter or member 'hba' not described in 'ufs_qcom_host_reset'
 drivers/scsi/ufs/ufs-qcom.c:383: warning: Function parameter or member 'hba' not described in 'ufs_qcom_cfg_timers'
 drivers/scsi/ufs/ufs-qcom.c:383: warning: Function parameter or member 'gear' not described in 'ufs_qcom_cfg_timers'
 drivers/scsi/ufs/ufs-qcom.c:383: warning: Function parameter or member 'hs' not described in 'ufs_qcom_cfg_timers'
 drivers/scsi/ufs/ufs-qcom.c:383: warning: Function parameter or member 'rate' not described in 'ufs_qcom_cfg_timers'
 drivers/scsi/ufs/ufs-qcom.c:383: warning: Function parameter or member 'update_link_startup_timer' not described in 'ufs_qcom_cfg_timers'
 drivers/scsi/ufs/ufs-qcom.c:1738: error: Cannot parse struct or union!

Link: https://lore.kernel.org/r/20200723122446.1329773-4-lee.jones@linaro.org
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: Avri Altman <avri.altman@wdc.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: linux-arm-msm@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-24 22:31:54 -04:00
Eric Biggers
df4ec2fa7a scsi: ufs-qcom: Add Inline Crypto Engine support
Add support for Qualcomm Inline Crypto Engine (ICE) to ufs-qcom.

The standards-compliant parts, such as querying the crypto capabilities and
enabling crypto for individual UFS requests, are already handled by
ufshcd-crypto.c, which itself is wired into the blk-crypto framework.
However, ICE requires vendor-specific init, enable, and resume logic, and
it requires that keys be programmed and evicted by vendor-specific SMC
calls.  Make the ufs-qcom driver handle these details.

I tested this on Dragonboard 845c, which is a publicly available
development board that uses the Snapdragon 845 SoC and runs the upstream
Linux kernel.  This is the same SoC used in the Pixel 3 and Pixel 3 XL
phones.  This testing included (among other things) verifying that the
expected ciphertext was produced, both manually using ext4 encryption and
automatically using a block layer self-test I've written.

I've also tested that this driver works nearly as-is on the Snapdragon 765
and Snapdragon 865 SoCs.  And others have tested it on Snapdragon 850,
Snapdragon 855, and Snapdragon 865 (see the Tested-by tags).

This is based very loosely on the vendor-provided driver in the kernel
source code for the Pixel 3, but I've greatly simplified it.  Also, for now
I've only included support for major version 3 of ICE, since that's all I
have the hardware to test with the mainline kernel.  Plus it appears that
version 3 is easier to use than older versions of ICE.

For now, only allow using AES-256-XTS.  The hardware also declares support
for AES-128-XTS, AES-{128,256}-ECB, and AES-{128,256}-CBC (BitLocker
variant).  But none of these others are really useful, and they'd need to
be individually tested to be sure they worked properly.

This commit also changes the name of the loadable module from "ufs-qcom" to
"ufs_qcom", as this is necessary to compile it from multiple source files
(unless we were to rename ufs-qcom.c).

Link: https://lore.kernel.org/r/20200710072013.177481-6-ebiggers@kernel.org
Tested-by: Steev Klimaszewski <steev@kali.org> # Lenovo Yoga C630
Tested-by: Thara Gopinath <thara.gopinath@linaro.org> # db845c, sm8150-mtp, sm8250-mtp
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-24 22:09:54 -04:00
Eric Biggers
1bc726e26e scsi: ufs: Add program_key() variant op
On Snapdragon SoCs, the Linux kernel isn't permitted to directly access the
standard UFS crypto configuration registers.  Instead, programming and
evicting keys must be done through vendor-specific SMC calls.

To support this hardware, add a ->program_key() method to 'struct
ufs_hba_variant_ops'.  This allows overriding the UFS standard key
programming / eviction procedure.

Link: https://lore.kernel.org/r/20200710072013.177481-5-ebiggers@kernel.org
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-24 22:09:54 -04:00
Eric Biggers
083dd788e4 scsi: ufs-qcom: Name the dev_ref_clk_ctrl registers
In preparation for adding another optional register range to the ufs-qcom
driver, name the existing optional register range "dev_ref_clk_ctrl_mem".
This allows the driver to refer to the optional register ranges by name
rather than index.

No device-tree files actually have to be updated due to this change, since
none of them actually declares these registers.

Link: https://lore.kernel.org/r/20200710072013.177481-3-ebiggers@kernel.org
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-24 22:09:54 -04:00
Stanley Chu
46426552e7 scsi: ufs-mediatek: Add inline encryption support
Add inline encryption support to ufs-mediatek.

The standards-compliant parts, such as querying the crypto capabilities and
enabling crypto for individual UFS requests, are already handled by
ufshcd-crypto.c, which itself is wired into the blk-crypto framework.

However MediaTek UFS host requires a vendor-specific hce_enable operation
to allow crypto-related registers being accessed normally in kernel.  After
this step, MediaTek UFS host can work as standard-compliant host for
inline-encryption related functions.

Link: https://lore.kernel.org/r/20200712003226.7593-1-stanley.chu@mediatek.com
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-13 23:24:56 -04:00
Stanley Chu
6edfdcfe28 scsi: ufs: Fix and simplify setup_xfer_req variant operation
Add missing setup_xfer_req() call in ufshcd_issue_devman_upiu_cmd() in
ufs-bsg path. Relocate existing setup_xfer_req() calls to a common place,
i.e., ufshcd_send_command(), to simplify the driver.

Link: https://lore.kernel.org/r/20200706060707.32608-3-stanley.chu@mediatek.com
Acked-by: Avri Altman <Avri.Altman@wdc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-13 22:51:56 -04:00
Stanley Chu
a3170376f7 scsi: ufs: Simplify completion timestamp for SCSI and query commands
Simplify recording command completion time in __ufshcd_transfer_req_compl()
by assigning lrbp->compl_time_stamp in a unified location.

Link: https://lore.kernel.org/r/20200706060707.32608-2-stanley.chu@mediatek.com
Acked-by: Avri Altman <Avri.Altman@wdc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-13 22:51:55 -04:00
Satya Tangirala
df043c745e scsi: ufs: Add inline encryption support to UFS
Wire up ufshcd.c with the UFS Crypto API, the block layer inline encryption
additions and the keyslot manager.

Many existing inline crypto devices require some additional behaviour not
specified in the UFSHCI v2.1 specification - as such the vendor specific
drivers will need to be updated where necessary to make it possible to use
those devices. Some of these changes have already been proposed upstream,
such as for the Qualcomm 845 SoC at
https://lkml.kernel.org/linux-scsi/20200501045111.665881-1-ebiggers@kernel.org/
and for ufs-mediatek at
https://lkml.kernel.org/linux-scsi/20200304022101.14165-1-stanley.chu@mediatek.com/

This patch has been tested on the db845c, sm8150-mtp and sm8250-mtp
(which have Qualcomm chipsets) and on some mediatek chipsets using these
aforementioned vendor specific driver updates.

Link: https://lore.kernel.org/r/20200706200414.2027450-4-satyat@google.com
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-08 01:23:32 -04:00
Satya Tangirala
70297a8ac7 scsi: ufs: UFS crypto API
Introduce functions to manipulate UFS inline encryption hardware in line
with the JEDEC UFSHCI v2.1 specification and to work with the block keyslot
manager.

The UFS crypto API will assume by default that a vendor driver doesn't
support UFS crypto, even if the hardware advertises the capability, because
a lot of hardware requires some special handling that's not specified in
the aforementioned JEDEC spec. Each vendor driver must explicitly set
hba->caps |= UFSHCD_CAP_CRYPTO before ufshcd_hba_init_crypto_capabilities()
is called to opt-in to UFS crypto support.

Link: https://lore.kernel.org/r/20200706200414.2027450-3-satyat@google.com
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-08 01:23:29 -04:00
Satya Tangirala
5e7341e1f9 scsi: ufs: UFS driver v2.1 spec crypto additions
Add the crypto registers and structs defined in v2.1 of the JEDEC UFSHCI
specification in preparation to add support for inline encryption to UFS.

Link: https://lore.kernel.org/r/20200706200414.2027450-2-satyat@google.com
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-08 01:21:59 -04:00
Bean Huo
a23064c412 scsi: ufs: Change upiu_flags to be u8
According to the UFS Spec, the Flags field in the UPIU is one byte in size,
not 4. Change it to be u8.

Link: https://lore.kernel.org/r/20200706123936.24799-1-huobean@gmail.com
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-08 01:08:14 -04:00
Dan Carpenter
b7a80dac0f scsi: ufs: ufs-exynos: Remove an unnecessary NULL check
The "head" pointer can't be NULL because it points to an address in the
middle of a ufs_hba struct.  Looking at this code, probably someone would
wonder if the intent was to check whether "hba" is NULL, but "hba" isn't
NULL and the check can just be removed.

Link: https://lore.kernel.org/r/20200626105133.GF314359@mwanda
Acked-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-06-29 21:33:20 -04:00
Stanley Chu
a7f1e69d49 scsi: ufs: Disable WriteBooster capability for non-supported UFS devices
If a UFS device is not qualified to use WriteBooster, either due to wrong
UFS version or device-specific quirks, then the capability in host shall be
disabled to prevent any WriteBooster operations in the future.

Link: https://lore.kernel.org/r/20200625030430.25048-1-stanley.chu@mediatek.com
Fixes: 3d17b9b5ab ("scsi: ufs: Add write booster feature support")
Tested-by: Steev Klimaszewski <steev@kali.org>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-06-26 22:44:22 -04:00
Alim Akhtar
6c9b3b2aa2 scsi: ufs: ufs-exynos: Fix build warning
While building for x86_64 allmodconfig, the following warning was reported:

WARNING: modpost: missing MODULE_LICENSE() in drivers/scsi/ufs/ufs-exynos.o

Add the missing license/author/description tags.

Link: https://lore.kernel.org/r/20200625154405.60448-1-alim.akhtar@samsung.com
Fixes: 55f4b1f736 ("scsi: ufs: ufs-exynos: Add UFS host support for Exynos SoCs")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-06-26 22:22:54 -04:00
Wei Yongjun
b2bc2200e8 scsi: ufs: ufs-exynos: Fix return value check in exynos_ufs_init()
In case of error, the function devm_ioremap_resource() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should be
replaced with IS_ERR().

Link: https://lore.kernel.org/r/20200618133837.127274-1-weiyongjun1@huawei.com
Fixes: 55f4b1f736 ("scsi: ufs: ufs-exynos: Add UFS host support for Exynos SoCs")
Reported-by: Hulk Robot <hulkci@huawei.com>
Acked-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-06-24 00:14:55 -04:00
Alim Akhtar
d31503fe39 scsi: ufs: Allow exynos ufs driver to build as module
Allow Exynos UFS driver to build as a module.  This patch fixes the
followin build issue reported by kernel build robot.

drivers/scsi/ufs/ufs-exynos.o: in function `exynos_ufs_probe':
drivers/scsi/ufs/ufs-exynos.c:1231: undefined reference to `ufshcd_pltfrm_init'
drivers/scsi/ufs/ufs-exynos.o: in function `exynos_ufs_pre_pwr_mode':
drivers/scsi/ufs/ufs-exynos.c:635: undefined reference to `ufshcd_get_pwr_dev_param'
drivers/scsi/ufs/ufs-exynos.o:undefined reference to `ufshcd_pltfrm_shutdown'
drivers/scsi/ufs/ufs-exynos.o:undefined reference to `ufshcd_pltfrm_suspend'
drivers/scsi/ufs/ufs-exynos.o:undefined reference to `ufshcd_pltfrm_resume'
drivers/scsi/ufs/ufs-exynos.o:undefined reference to `ufshcd_pltfrm_runtime_suspend'
drivers/scsi/ufs/ufs-exynos.o:undefined reference to `ufshcd_pltfrm_runtime_resume'
drivers/scsi/ufs/ufs-exynos.o:undefined reference to `ufshcd_pltfrm_runtime_idle'

Link: https://lore.kernel.org/r/20200620173232.52521-1-alim.akhtar@samsung.com
Fixes: 55f4b1f736 ("scsi: ufs: ufs-exynos: Add UFS host support for Exynos SoCs")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-06-24 00:09:31 -04:00
Colin Ian King
393403efc3 scsi: ufs: ufs-exynos: Fix spelling mistake "pa_granularty" -> "pa_granularity"
There is a spelling mistake in a dev_warn message. Fix it.

Link: https://lore.kernel.org/r/20200617084911.167359-1-colin.king@canonical.com
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-06-19 22:54:17 -04:00
Stanley Chu
9a3cd470f8 scsi: ufs-mediatek: Make ufs_mtk_wait_link_state static
Fix build warning reported by kernel test robot:

Warning:
>> drivers/scsi/ufs/ufs-mediatek.c:181:5: warning: no previous prototype
>> for 'ufs_mtk_wait_link_state' [-Wmissing-prototypes]

Link: https://lore.kernel.org/r/20200616095120.14570-1-stanley.chu@mediatek.com
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-06-19 22:53:35 -04:00
Stanley Chu
b1bf66d1d5 scsi: ufs: Fix imprecise load calculation in devfreq window
The UFS load calculation is based on "total_time" and "busy_time" in a
devfreq window.  However, the source of time is different for both
parameters: "busy_time" is assigned from "jiffies" thus has different
accuracy from "total_time" which is assigned from ktime_get().

In addition, the time of window boundary is not exactly the same as the
starting busy time in this window if UFS is actually busy in the beginning
of the window. A similar accuracy error may also happen for the end of busy
time in current window.

To guarantee the precision of load calculation, we need to

1. Align time accuracy of both devfreq_dev_status.total_time and
   devfreq_dev_status.busy_time. For example, use "ktime_get()" directly.

2. Align the following timelines:
   - The beginning time of devfreq windows
   - The beginning of busy time in a new window
   - The end of busy time in the current window

Link: https://lore.kernel.org/r/20200611101043.6379-1-stanley.chu@mediatek.com
Fixes: a3cd5ec55f ("scsi: ufs: add load based scaling of UFS gear")
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-06-15 23:39:00 -04:00