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| author | Subhash Jadavani <subhashj@codeaurora.org> | 2019-11-15 09:09:30 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-04 21:13:03 +0300 |
| commit | a4c9fd613eec085df74de61c55138cbc4ba6b84c (patch) | |
| tree | f2bbd195fb9bed87cc81ed926bfeeee3af5270d5 /drivers/scsi | |
| parent | c153c121539fd845a564f96397b732b10f8baa30 (diff) | |
| download | linux-a4c9fd613eec085df74de61c55138cbc4ba6b84c.tar.xz | |
scsi: ufs: Fix error handing during hibern8 enter
[ Upstream commit 6d303e4b19d694cdbebf76bcdb51ada664ee953d ]
During clock gating (ufshcd_gate_work()), we first put the link hibern8 by
calling ufshcd_uic_hibern8_enter() and if ufshcd_uic_hibern8_enter()
returns success (0) then we gate all the clocks. Now let’s zoom in to what
ufshcd_uic_hibern8_enter() does internally: It calls
__ufshcd_uic_hibern8_enter() and if failure is encountered, link recovery
shall put the link back to the highest HS gear and returns success (0) to
ufshcd_uic_hibern8_enter() which is the issue as link is still in active
state due to recovery! Now ufshcd_uic_hibern8_enter() returns success to
ufshcd_gate_work() and hence it goes ahead with gating the UFS clock while
link is still in active state hence I believe controller would raise UIC
error interrupts. But when we service the interrupt, clocks might have
already been disabled!
This change fixes for this by returning failure from
__ufshcd_uic_hibern8_enter() if recovery succeeds as link is still not in
hibern8, upon receiving the error ufshcd_hibern8_enter() would initiate
retry to put the link state back into hibern8.
Link: https://lore.kernel.org/r/1573798172-20534-8-git-send-email-cang@codeaurora.org
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/ufs/ufshcd.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 7510d8328d4d..3601e770da16 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3875,15 +3875,24 @@ static int __ufshcd_uic_hibern8_enter(struct ufs_hba *hba) ktime_to_us(ktime_sub(ktime_get(), start)), ret); if (ret) { + int err; + dev_err(hba->dev, "%s: hibern8 enter failed. ret = %d\n", __func__, ret); /* - * If link recovery fails then return error so that caller - * don't retry the hibern8 enter again. + * If link recovery fails then return error code returned from + * ufshcd_link_recovery(). + * If link recovery succeeds then return -EAGAIN to attempt + * hibern8 enter retry again. */ - if (ufshcd_link_recovery(hba)) - ret = -ENOLINK; + err = ufshcd_link_recovery(hba); + if (err) { + dev_err(hba->dev, "%s: link recovery failed", __func__); + ret = err; + } else { + ret = -EAGAIN; + } } else ufshcd_vops_hibern8_notify(hba, UIC_CMD_DME_HIBER_ENTER, POST_CHANGE); @@ -3897,7 +3906,7 @@ static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba) for (retries = UIC_HIBERN8_ENTER_RETRIES; retries > 0; retries--) { ret = __ufshcd_uic_hibern8_enter(hba); - if (!ret || ret == -ENOLINK) + if (!ret) goto out; } out: |