[PATCH v1 01/11] scsi: ufs: add queries retry mechanism

From: Subhash Jadavani
Date: Wed Nov 23 2016 - 19:32:05 EST


From: Dolev Raviv <draviv@xxxxxxxxxxxxxx>

Some of the queries might fail during init. To avoid
system failure, we add retry mechanism to issue queries
several times.

Signed-off-by: Dolev Raviv <draviv@xxxxxxxxxxxxxx>
Signed-off-by: Subhash Jadavani <subhashj@xxxxxxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 54 +++++++++++++++++++++++++++++++++++++++--------
1 file changed, 45 insertions(+), 9 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index f91e50b..0b278a1 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -2141,7 +2141,18 @@ static inline int ufshcd_read_power_desc(struct ufs_hba *hba,
u8 *buf,
u32 size)
{
- return ufshcd_read_desc(hba, QUERY_DESC_IDN_POWER, 0, buf, size);
+ int err = 0;
+ int retries;
+
+ for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
+ /* Read descriptor*/
+ err = ufshcd_read_desc(hba, QUERY_DESC_IDN_POWER, 0, buf, size);
+ if (!err)
+ break;
+ dev_dbg(hba->dev, "%s: error %d retrying\n", __func__, err);
+ }
+
+ return err;
}

int ufshcd_read_device_desc(struct ufs_hba *hba, u8 *buf, u32 size)
@@ -3251,16 +3262,24 @@ static void ufshcd_set_queue_depth(struct scsi_device *sdev)
{
int ret = 0;
u8 lun_qdepth;
+ int retries;
struct ufs_hba *hba;

hba = shost_priv(sdev->host);

lun_qdepth = hba->nutrs;
- ret = ufshcd_read_unit_desc_param(hba,
- ufshcd_scsi_to_upiu_lun(sdev->lun),
- UNIT_DESC_PARAM_LU_Q_DEPTH,
- &lun_qdepth,
- sizeof(lun_qdepth));
+ for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
+ /* Read descriptor*/
+ ret = ufshcd_read_unit_desc_param(hba,
+ ufshcd_scsi_to_upiu_lun(sdev->lun),
+ UNIT_DESC_PARAM_LU_Q_DEPTH,
+ &lun_qdepth,
+ sizeof(lun_qdepth));
+ if (!ret || ret == -ENOTSUPP)
+ break;
+
+ dev_dbg(hba->dev, "%s: error %d retrying\n", __func__, ret);
+ }

/* Some WLUN doesn't support unit descriptor */
if (ret == -EOPNOTSUPP)
@@ -4796,6 +4815,24 @@ static u32 ufshcd_find_max_sup_active_icc_level(struct ufs_hba *hba,
return icc_level;
}

+static int ufshcd_set_icc_levels_attr(struct ufs_hba *hba, u32 icc_level)
+{
+ int ret = 0;
+ int retries;
+
+ for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
+ /* write attribute */
+ ret = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
+ QUERY_ATTR_IDN_ACTIVE_ICC_LVL, 0, 0, &icc_level);
+ if (!ret)
+ break;
+
+ dev_dbg(hba->dev, "%s: failed with error %d\n", __func__, ret);
+ }
+
+ return ret;
+}
+
static void ufshcd_init_icc_levels(struct ufs_hba *hba)
{
int ret;
@@ -4816,9 +4853,8 @@ static void ufshcd_init_icc_levels(struct ufs_hba *hba)
dev_dbg(hba->dev, "%s: setting icc_level 0x%x",
__func__, hba->init_prefetch_data.icc_level);

- ret = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
- QUERY_ATTR_IDN_ACTIVE_ICC_LVL, 0, 0,
- &hba->init_prefetch_data.icc_level);
+ ret = ufshcd_set_icc_levels_attr(hba,
+ hba->init_prefetch_data.icc_level);

if (ret)
dev_err(hba->dev,
--
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