lkml.org 
[lkml]   [2023]   [May]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH v5 7/7] ufs: core: Add error handling for MCQ mode
From
On 5/21/2023 11:56 PM, Stanley Chu wrote:
> On Mon, May 22, 2023 at 2:48 PM Stanley Chu <chu.stanley@gmail.com> wrote:
>>
>> Hi Bao,
>>
>> Bao D. Nguyen <quic_nguyenb@quicinc.com> 於 2023年5月12日 週五 下午2:34寫道:
>>>
>>> Add support for error handling for MCQ mode.
>>>
>>> Signed-off-by: Bao D. Nguyen <quic_nguyenb@quicinc.com>
>>> ---
>>> drivers/ufs/core/ufshcd.c | 85 +++++++++++++++++++++++++++++++++++++++++------
>>> 1 file changed, 74 insertions(+), 11 deletions(-)
>>>
>>> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
>>> index ec07e49..9345118 100644
>>> --- a/drivers/ufs/core/ufshcd.c
>>> +++ b/drivers/ufs/core/ufshcd.c
>>> @@ -3148,6 +3148,16 @@ static int ufshcd_wait_for_dev_cmd(struct ufs_hba *hba,
>>> err = -ETIMEDOUT;
>>> dev_dbg(hba->dev, "%s: dev_cmd request timedout, tag %d\n",
>>> __func__, lrbp->task_tag);
>>> +
>>> + /* MCQ mode */
>>> + if (is_mcq_enabled(hba)) {
>>> + err = ufshcd_clear_cmd(hba, lrbp->task_tag);
>>> + if (!err)
>>> + hba->dev_cmd.complete = NULL;
>>
>> How about always clearing hba->dev_cmd.complete? If ufshcd_clear_cmd()
>> fails (for example, times out), "complete" should be cleared, similar
>> to the "pending" case in the SDB path.
>>
>>> + return err;
>>> + }
>>> +
>>> + /* SDB mode */
>>> if (ufshcd_clear_cmd(hba, lrbp->task_tag) == 0) {
>>> /* successfully cleared the command, retry if needed */
>>> err = -EAGAIN;
>>> @@ -5581,6 +5591,10 @@ static int ufshcd_poll(struct Scsi_Host *shost, unsigned int queue_num)
>>> */
>>> static irqreturn_t ufshcd_transfer_req_compl(struct ufs_hba *hba)
>>> {
>>> + struct ufshcd_lrb *lrbp;
>>> + u32 hwq_num, utag;
>>> + int tag;
>>> +
>>> /* Resetting interrupt aggregation counters first and reading the
>>> * DOOR_BELL afterward allows us to handle all the completed requests.
>>> * In order to prevent other interrupts starvation the DB is read once
>>> @@ -5599,7 +5613,22 @@ static irqreturn_t ufshcd_transfer_req_compl(struct ufs_hba *hba)
>>> * Ignore the ufshcd_poll() return value and return IRQ_HANDLED since we
>>> * do not want polling to trigger spurious interrupt complaints.
>>> */
>>> - ufshcd_poll(hba->host, UFSHCD_POLL_FROM_INTERRUPT_CONTEXT);
>>> + if (!is_mcq_enabled(hba)) {
>>> + ufshcd_poll(hba->host, UFSHCD_POLL_FROM_INTERRUPT_CONTEXT);
>>> + goto out;
>>> + }
>>> +
>>> + /* MCQ mode */
>>> + for (tag = 0; tag < hba->nutrs; tag++) {
>>> + lrbp = &hba->lrb[tag];
>>> + if (ufshcd_cmd_inflight(lrbp->cmd)) {
>>> + utag = blk_mq_unique_tag(scsi_cmd_to_rq(lrbp->cmd));
>>> + hwq_num = blk_mq_unique_tag_to_hwq(utag);
>>> + ufshcd_poll(hba->host, hwq_num);
>>> + }
>>> + }
>>
>> In SDB mode, the DOOR_BELL is reset by ufshcd_hba_stop(). All bits
>> that were previously set in DOOR_BELL are also set in "completed_reqs"
>> in ufshcd_poll(). This allows ufshcd_poll() to handle all outstanding
>> requests properly.
>>
>> However, in MCQ mode, the CQ tail registers cannot provide the same
>> information after they are reset. Hence, they cannot be properly
>> referenced by ufshcd_poll().
>
> A fixed version sample is as follows and has been tested on our end.
Thank you Stanley. I will make the change.

>
> struct scsi_cmnd *cmd;
>
> for (tag = 0; tag < hba->nutrs; tag++) {
> lrbp = &hba->lrb[tag];
> cmd = lrbp->cmd;
> if (ufshcd_cmd_inflight(cmd)) {
> set_host_byte(cmd, DID_ERROR);
> ufshcd_release_scsi_cmd(hba, lrbp);
> scsi_done(cmd);
> }
> }
>
> Thanks,
> Stanley Chu

\
 
 \ /
  Last update: 2023-05-23 09:02    [W:0.050 / U:0.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site