[PATCH v1 11/15] scsi: ufs: retry failed query flag requests

From: Yaniv Gardi
Date: Fri Aug 21 2015 - 18:10:51 EST


UFS flag query requests may fail sometimes due to timeouts etc.
Add a wrapper function to retry up to 10 times in case of such
failure, similar to retries being made for attribute queries.

Signed-off-by: Yaniv Gardi <ygardi@xxxxxxxxxxxxxx>

---
drivers/scsi/ufs/ufshcd.c | 63 ++++++++++++++++++++++++++++-------------------
drivers/scsi/ufs/ufshcd.h | 4 +++
2 files changed, 41 insertions(+), 26 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 30aec4d..0a8aa88 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1662,6 +1662,29 @@ static inline void ufshcd_init_query(struct ufs_hba *hba,
(*request)->upiu_req.selector = selector;
}

+static int ufshcd_query_flag_retry(struct ufs_hba *hba,
+ enum query_opcode opcode, enum flag_idn idn, bool *flag_res)
+{
+ int ret;
+ int retries;
+
+ for (retries = 0; retries < QUERY_REQ_RETRIES; retries++) {
+ ret = ufshcd_query_flag(hba, opcode, idn, flag_res);
+ if (ret)
+ dev_dbg(hba->dev,
+ "%s: failed with error %d, retries %d\n",
+ __func__, ret, retries);
+ else
+ break;
+ }
+
+ if (ret)
+ dev_err(hba->dev,
+ "%s: query attribute, opcode %d, idn %d, failed with error %d after %d retires\n",
+ __func__, opcode, idn, ret, retries);
+ return ret;
+}
+
/**
* ufshcd_query_flag() - API function for sending flag query requests
* hba: per-adapter instance
@@ -1671,7 +1694,7 @@ static inline void ufshcd_init_query(struct ufs_hba *hba,
*
* Returns 0 for success, non-zero in case of failure
*/
-static int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
+int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
enum flag_idn idn, bool *flag_res)
{
struct ufs_query_req *request = NULL;
@@ -2656,17 +2679,12 @@ static int ufshcd_config_pwr_mode(struct ufs_hba *hba,
*/
static int ufshcd_complete_dev_init(struct ufs_hba *hba)
{
- int i, retries, err = 0;
+ int i;
+ int err;
bool flag_res = 1;

- for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
- /* Set the fDeviceInit flag */
- err = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_SET_FLAG,
- QUERY_FLAG_IDN_FDEVICEINIT, NULL);
- if (!err || err == -ETIMEDOUT)
- break;
- dev_dbg(hba->dev, "%s: error %d retrying\n", __func__, err);
- }
+ err = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_SET_FLAG,
+ QUERY_FLAG_IDN_FDEVICEINIT, NULL);
if (err) {
dev_err(hba->dev,
"%s setting fDeviceInit flag failed with error %d\n",
@@ -2674,18 +2692,11 @@ static int ufshcd_complete_dev_init(struct ufs_hba *hba)
goto out;
}

- /* poll for max. 100 iterations for fDeviceInit flag to clear */
- for (i = 0; i < 100 && !err && flag_res; i++) {
- for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
- err = ufshcd_query_flag(hba,
- UPIU_QUERY_OPCODE_READ_FLAG,
- QUERY_FLAG_IDN_FDEVICEINIT, &flag_res);
- if (!err || err == -ETIMEDOUT)
- break;
- dev_dbg(hba->dev, "%s: error %d retrying\n", __func__,
- err);
- }
- }
+ /* poll for max. 1000 iterations for fDeviceInit flag to clear */
+ for (i = 0; i < 1000 && !err && flag_res; i++)
+ err = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_READ_FLAG,
+ QUERY_FLAG_IDN_FDEVICEINIT, &flag_res);
+
if (err)
dev_err(hba->dev,
"%s reading fDeviceInit flag failed with error %d\n",
@@ -3432,7 +3443,7 @@ static int ufshcd_enable_auto_bkops(struct ufs_hba *hba)
if (hba->auto_bkops_enabled)
goto out;

- err = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_SET_FLAG,
+ err = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_SET_FLAG,
QUERY_FLAG_IDN_BKOPS_EN, NULL);
if (err) {
dev_err(hba->dev, "%s: failed to enable bkops %d\n",
@@ -3481,7 +3492,7 @@ static int ufshcd_disable_auto_bkops(struct ufs_hba *hba)
goto out;
}

- err = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_CLEAR_FLAG,
+ err = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_CLEAR_FLAG,
QUERY_FLAG_IDN_BKOPS_EN, NULL);
if (err) {
dev_err(hba->dev, "%s: failed to disable bkops %d\n",
@@ -4452,8 +4463,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)

/* clear any previous UFS device information */
memset(&hba->dev_info, 0, sizeof(hba->dev_info));
- if (!ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_READ_FLAG,
- QUERY_FLAG_IDN_PWR_ON_WPE, &flag))
+ if (!ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_READ_FLAG,
+ QUERY_FLAG_IDN_PWR_ON_WPE, &flag))
hba->dev_info.f_power_on_wp_en = flag;

if (!hba->is_init_prefetch)
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 4bb2697..2e8f64b 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -3,6 +3,7 @@
*
* This code is based on drivers/scsi/ufs/ufshcd.h
* Copyright (C) 2011-2013 Samsung India Software Operations
+ * Copyright (c) 2013-2015, The Linux Foundation. All rights reserved.
*
* Authors:
* Santosh Yaraganavi <santosh.sy@xxxxxxxxxxx>
@@ -680,6 +681,9 @@ static inline int ufshcd_dme_peer_get(struct ufs_hba *hba,
return ufshcd_dme_get_attr(hba, attr_sel, mib_val, DME_PEER);
}

+/* Expose Query-Request API */
+int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
+ enum flag_idn idn, bool *flag_res);
int ufshcd_hold(struct ufs_hba *hba, bool async);
void ufshcd_release(struct ufs_hba *hba);

--
1.8.5.2

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