Re: [EXT] [PATCH v1 1/2] scsi: ufs: Introduce a vops for resetting host controller

From: cang
Date: Mon Oct 28 2019 - 22:11:10 EST


On 2019-10-23 18:39, Bean Huo (beanhuo) wrote:
Hi, Can Guo
Actually, we already have DME_RESET, this is not enough for Qualcomm host?
Thanks,

//Bean


Hi Bean,

Yes, for Qualcomm hosts, we need this to fully reset the whole UFS controller block

Can Guo


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); @@ -6241,6 +6249,11
@@ static int ufshcd_reset_and_restore(struct ufs_hba *hba)
int retries = MAX_HOST_RESET_RETRIES;

do {
+ err = ufshcd_vops_full_reset(hba);
+ if (err)
+ dev_warn(hba->dev, "%s: full reset returned %d\n",
+ __func__, err);
+
/* Reset the attached device */
ufshcd_vops_device_reset(hba);

@@ -8384,6 +8397,9 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem
*mmio_base, unsigned int irq)
goto exit_gating;
}

+ /* Reset controller to power on reset (POR) state */
+ ufshcd_vops_full_reset(hba);
+
/* Reset the attached device */
ufshcd_vops_device_reset(hba);

diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index
e0fe247..253b9ea 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -296,6 +296,8 @@ struct ufs_pwr_mode_info {
* @apply_dev_quirks: called to apply device specific quirks
* @suspend: called during host controller PM callback
* @resume: called during host controller PM callback
+ * @full_reset: called for handling variant specific implementations of
+ * resetting the hci
* @dbg_register_dump: used to dump controller debug information
* @phy_initialization: used to initialize phys
* @device_reset: called to issue a reset pulse on the UFS device @@ -325,6
+327,7 @@ struct ufs_hba_variant_ops {
int (*apply_dev_quirks)(struct ufs_hba *);
int (*suspend)(struct ufs_hba *, enum ufs_pm_op);
int (*resume)(struct ufs_hba *, enum ufs_pm_op);
+ int (*full_reset)(struct ufs_hba *hba);
void (*dbg_register_dump)(struct ufs_hba *hba);
int (*phy_initialization)(struct ufs_hba *);
void (*device_reset)(struct ufs_hba *hba);
@@ -1076,6 +1079,13 @@ static inline int ufshcd_vops_resume(struct ufs_hba
*hba, enum ufs_pm_op op)
return 0;
}

+static inline int ufshcd_vops_full_reset(struct ufs_hba *hba) {
+ if (hba->vops && hba->vops->full_reset)
+ return hba->vops->full_reset(hba);
+ return 0;
+}
+
static inline void ufshcd_vops_dbg_register_dump(struct ufs_hba *hba) {
if (hba->vops && hba->vops->dbg_register_dump)
--
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