diff options
author | Subhash Jadavani <subhashj@codeaurora.org> | 2019-11-14 22:09:30 -0800 |
---|---|---|
committer | Martin K. Petersen <martin.petersen@oracle.com> | 2019-11-19 21:37:32 -0500 |
commit | 6d303e4b19d694cdbebf76bcdb51ada664ee953d (patch) | |
tree | f261c501808f01e5d484a982360f191e4883b65f /drivers/scsi/ufs | |
parent | 18f01374b55b4595ad7f56250891bdbdb9d7a052 (diff) | |
download | linux-6d303e4b19d694cdbebf76bcdb51ada664ee953d.tar.gz linux-6d303e4b19d694cdbebf76bcdb51ada664ee953d.tar.bz2 linux-6d303e4b19d694cdbebf76bcdb51ada664ee953d.zip |
scsi: ufs: Fix error handing during hibern8 enter
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>
Diffstat (limited to 'drivers/scsi/ufs')
-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 180593ac4062..b5966faf3e98 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3891,15 +3891,24 @@ 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); @@ -3913,7 +3922,7 @@ 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: |