On 10/22/19 9:13 PM, Can Guo wrote:
Some UFS host controllers need their specific implementations of resetting
to get them into a good state. Provide a new vops to allow the platform
driver to implement this own reset operation.
Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 16 ++++++++++++++++
drivers/scsi/ufs/ufshcd.h | 10 ++++++++++
2 files changed, 26 insertions(+)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index c28c144..161e3c4 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3859,6 +3859,14 @@ static int ufshcd_link_recovery(struct ufs_hba *hba)
ufshcd_set_eh_in_progress(hba);
spin_unlock_irqrestore(hba->host->host_lock, flags);
+ ret = ufshcd_vops_full_reset(hba);
+ if (ret)
+ dev_warn(hba->dev, "%s: full reset returned %d\n",
+ __func__, ret);
+
+ /* Reset the attached device */
+ ufshcd_vops_device_reset(hba);
+
ret = ufshcd_host_reset_and_restore(hba);
spin_lock_irqsave(hba->host->host_lock, flags);
In all your cases, especially after this adjustment,
ufshcd_vops_full_reset is called blindly (+error checking message)
before ufshcd_vops_device_reset. What about dropping the .full_reset
(should really have been called .hw_reset or .host_reset) addition to
the vops, just adding ufshcd_vops_device_reset call here before
ufshcd_host_reset_and_restore, and in the driver folding the
ufshcd_vops_full_reset code into the .device_reset handler?
Would that be workable? It would be simpler if so.
I can see a desire for the heads up
(ufshcd_vops_full_reset+)ufshcd_vops_device_reset calls before
ufshcd_host_reset_and_restore because that function will spin 10 seconds
waiting for a response from a standardized register, that itself could
be hardware locked up requiring product specific reset procedures. But
if that is the case, then what about all the other calls to
ufshcd_host_reset_and_restore in this file that are not provided the
heads up? My guess is that the host device only demonstrated issues in
the ufshcd_link_recovery handling path? Are you sure this is the only
path that tickles the controller into a hardware lockup state?
Sincerely -- Mark Salyzyn
