> On Aug 21, 2015 3:10 PM, "Yaniv Gardi" <ygardi@xxxxxxxxxxxxxx> wrote:
>>
>> Sometimes queries from the device might return a failure so it is
>> recommended to retry sending the query, before giving up.
>> This change adds a wrapper to retry sending a query attribute,
>> in cases where we need to wait longer, before we continue,
>> or before reporting a failure.
>
> Why not just always retry? Are there cases where retrying would be a
> problem?
There is no problem to retry whenever we encounter a query that returns
with and error.
In the code, it's recommended to replace any call to
>
>
>>
>> Signed-off-by: Yaniv Gardi <ygardi@xxxxxxxxxxxxxx>
>>
>> ---
>> drivers/scsi/ufs/ufshcd.c | 51
>> ++++++++++++++++++++++++++++++++++++++++-------
>> 1 file changed, 44 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> index 876148b..bfef67d 100644
>> --- a/drivers/scsi/ufs/ufshcd.c
>> +++ b/drivers/scsi/ufs/ufshcd.c
>> @@ -1827,6 +1827,43 @@ out:
>> }
>>
>> /**
>> + * ufshcd_query_attr_retry() - API function for sending query
>> + * attribute with retries
>> + * @hba: per-adapter instance
>> + * @opcode: attribute opcode
>> + * @idn: attribute idn to access
>> + * @index: index field
>> + * @selector: selector field
>> + * @attr_val: the attribute value after the query request
>> + * completes
>> + *
>> + * Returns 0 for success, non-zero in case of failure
>> +*/
>> +static int ufshcd_query_attr_retry(struct ufs_hba *hba,
>> + enum query_opcode opcode, enum attr_idn idn, u8 index, u8
>> selector,
>> + u32 *attr_val)
>> +{
>> + int ret = 0;
>> + u32 retries;
>> +
>> + for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
>> + ret = ufshcd_query_attr(hba, opcode, idn, index,
>> + selector, attr_val);
>> + 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, idn %d, failed with error
>> %d after %d retires\n",
>> + __func__, idn, ret, retries);
>
> The retry count will be wrong here.
you are correct. will be fixed in V2
>
>> + return ret;
>> +}
>> +
>> +/**
>> * ufshcd_query_descriptor - API function for sending descriptor
>> requests
>> * hba: per-adapter instance
>> * opcode: attribute opcode
>> @@ -3407,7 +3444,7 @@ static int ufshcd_disable_ee(struct ufs_hba *hba,
>> u16 mask)
>>
>> val = hba->ee_ctrl_mask & ~mask;
>> val &= 0xFFFF; /* 2 bytes */
>> - err = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
>> + err = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
>> QUERY_ATTR_IDN_EE_CONTROL, 0, 0, &val);
>> if (!err)
>> hba->ee_ctrl_mask &= ~mask;
>> @@ -3435,7 +3472,7 @@ static int ufshcd_enable_ee(struct ufs_hba *hba,
>> u16 mask)
>>
>> val = hba->ee_ctrl_mask | mask;
>> val &= 0xFFFF; /* 2 bytes */
>> - err = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
>> + err = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
>> QUERY_ATTR_IDN_EE_CONTROL, 0, 0, &val);
>> if (!err)
>> hba->ee_ctrl_mask |= mask;
>> @@ -3541,7 +3578,7 @@ static void ufshcd_force_reset_auto_bkops(struct
>> ufs_hba *hba)
>>
>> static inline int ufshcd_get_bkops_status(struct ufs_hba *hba, u32
>> *status)
>> {
>> - return ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
>> + return ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
>> QUERY_ATTR_IDN_BKOPS_STATUS, 0, 0, status);
>> }
>>
>> @@ -3604,7 +3641,7 @@ static int ufshcd_urgent_bkops(struct ufs_hba
>> *hba)
>>
>> static inline int ufshcd_get_ee_status(struct ufs_hba *hba, u32
>> *status)
>> {
>> - return ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
>> + return ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
>> QUERY_ATTR_IDN_EE_STATUS, 0, 0, status);
>> }
>>
>> @@ -4360,9 +4397,9 @@ 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(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
>> - QUERY_ATTR_IDN_ACTIVE_ICC_LVL, 0, 0,
>> - &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);
>>
>> if (ret)
>> dev_err(hba->dev,
>> --
>> 1.8.5.2
>>
>> --
>> QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a
>> member of Code Aurora Forum, hosted by The Linux Foundation
>
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