scsi: ufs: mcq: Add support for cleaning up MCQ resources

Update ufshcd_clear_cmd() to clean up the MCQ resources similar to the
function ufshcd_utrl_clear() does for SDB mode.

Update ufshcd_try_to_abort_task() to support MCQ mode so that this function
can be invoked in either mcq or SDB mode.

Signed-off-by: Bao D. Nguyen <[email protected]>
Link: https://lore.kernel.org/r/dc6d30b3ee55e2072c162b2c08504ba349b87139.1685396241.git.quic_nguyenb@quicinc.com
Reviewed-by: Bart Van Assche <[email protected]>
Reviewed-by: Stanley Chu <[email protected]>
Tested-by: Stanley Chu <[email protected]>
Reviewed-by: Can Guo <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

Author: Bao D. Nguyen

drivers/ufs/core/ufshcd-priv.h

@@ -78,6 +78,7 @@ struct ufs_hw_queue *ufshcd_mcq_req_to_hwq(struct ufs_hba *hba,
 unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
 				       struct ufs_hw_queue *hwq);
 
+bool ufshcd_cmd_inflight(struct scsi_cmnd *cmd);
 int ufshcd_mcq_sq_cleanup(struct ufs_hba *hba, int task_tag);
 
 #define UFSHCD_MCQ_IO_QUEUE_OFFSET	1

drivers/ufs/core/ufshcd.c

@@ -2997,6 +2997,26 @@ static int ufshcd_compose_dev_cmd(struct ufs_hba *hba,
 	return ufshcd_compose_devman_upiu(hba, lrbp);
 }
 
+/*
+ * Check with the block layer if the command is inflight
+ * @cmd: command to check.
+ *
+ * Returns true if command is inflight; false if not.
+ */
+bool ufshcd_cmd_inflight(struct scsi_cmnd *cmd)
+{
+	struct request *rq;
+
+	if (!cmd)
+		return false;
+
+	rq = scsi_cmd_to_rq(cmd);
+	if (!blk_mq_request_started(rq))
+		return false;
+
+	return true;
+}
+
 /*
  * Clear the pending command in the controller and wait until
  * the controller confirms that the command has been cleared.
@@ -3005,8 +3025,23 @@ static int ufshcd_compose_dev_cmd(struct ufs_hba *hba,
  */
 static int ufshcd_clear_cmd(struct ufs_hba *hba, u32 task_tag)
 {
-	unsigned long flags;
 	u32 mask = 1U << task_tag;
+	unsigned long flags;
+	int err;
+
+	if (is_mcq_enabled(hba)) {
+		/*
+		 * MCQ mode. Clean up the MCQ resources similar to
+		 * what the ufshcd_utrl_clear() does for SDB mode.
+		 */
+		err = ufshcd_mcq_sq_cleanup(hba, task_tag);
+		if (err) {
+			dev_err(hba->dev, "%s: failed tag=%d. err=%d\n",
+				__func__, task_tag, err);
+			return err;
+		}
+		return 0;
+	}
 
 	/* clear outstanding transaction before retry */
 	spin_lock_irqsave(hba->host->host_lock, flags);
@@ -7377,6 +7412,20 @@ static int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag)
 			 */
 			dev_err(hba->dev, "%s: cmd at tag %d not pending in the device.\n",
 				__func__, tag);
+			if (is_mcq_enabled(hba)) {
+				/* MCQ mode */
+				if (ufshcd_cmd_inflight(lrbp->cmd)) {
+					/* sleep for max. 200us same delay as in SDB mode */
+					usleep_range(100, 200);
+					continue;
+				}
+				/* command completed already */
+				dev_err(hba->dev, "%s: cmd at tag=%d is cleared.\n",
+					__func__, tag);
+				goto out;
+			}
+
+			/* Single Doorbell Mode */
 			reg = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
 			if (reg & (1 << tag)) {
 				/* sleep for max. 200us to stabilize */
@@ -7442,13 +7491,16 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 	WARN_ONCE(tag < 0, "Invalid tag %d\n", tag);
 
 	ufshcd_hold(hba, false);
-	reg = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
-	/* If command is already aborted/completed, return FAILED. */
-	if (!(test_bit(tag, &hba->outstanding_reqs))) {
-		dev_err(hba->dev,
-			"%s: cmd at tag %d already completed, outstanding=0x%lx, doorbell=0x%x\n",
-			__func__, tag, hba->outstanding_reqs, reg);
-		goto release;
+
+	if (!is_mcq_enabled(hba)) {
+		reg = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
+		if (!test_bit(tag, &hba->outstanding_reqs)) {
+			/* If command is already aborted/completed, return FAILED. */
+			dev_err(hba->dev,
+				"%s: cmd at tag %d already completed, outstanding=0x%lx, doorbell=0x%x\n",
+				__func__, tag, hba->outstanding_reqs, reg);
+			goto release;
+		}
 	}
 
 	/* Print Transfer Request of aborted task */
@@ -7473,7 +7525,8 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 	}
 	hba->req_abort_count++;
 
-	if (!(reg & (1 << tag))) {
+	if (!is_mcq_enabled(hba) && !(reg & (1 << tag))) {
+		/* only execute this code in single doorbell mode */
 		dev_err(hba->dev,
 		"%s: cmd was completed, but without a notifying intr, tag = %d",
 		__func__, tag);
@@ -7499,6 +7552,9 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 		goto release;
 	}
 
+	if (is_mcq_enabled(hba))
+		goto release;
+
 	/* Skip task abort in case previous aborts failed and report failure */
 	if (lrbp->req_abort_skip) {
 		dev_err(hba->dev, "%s: skipping abort\n", __func__);