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From:   "Bao D. Nguyen" <quic_nguyenb@quicinc.com>
To:     <quic_asutoshd@quicinc.com>, <quic_cang@quicinc.com>,
        <bvanassche@acm.org>, <mani@kernel.org>,
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        <martin.petersen@oracle.com>
CC:     <linux-scsi@vger.kernel.org>,
        "Bao D. Nguyen" <quic_nguyenb@quicinc.com>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        Arthur Simchaev <Arthur.Simchaev@wdc.com>,
        "Krzysztof Kozlowski" <krzysztof.kozlowski@linaro.org>,
        open list <linux-kernel@vger.kernel.org>
Subject: [PATCH v6 4/7] ufs: mcq: Add support for clean up mcq resources
Date:   Tue, 23 May 2023 00:28:12 -0700
Message-ID: <cab786369106e637829701250ea76d97b3500373.1684825500.git.quic_nguyenb@quicinc.com>
In-Reply-To: <cover.1684825500.git.quic_nguyenb@quicinc.com>
References: <cover.1684825500.git.quic_nguyenb@quicinc.com>
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Precedence: bulk

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 <quic_nguyenb@quicinc.com>
---
 drivers/ufs/core/ufshcd-priv.h |  1 +
 drivers/ufs/core/ufshcd.c      | 74 +++++++++++++++++++++++++++++++++++++-----
 2 files changed, 66 insertions(+), 9 deletions(-)

diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index 40727e8..3f518e9 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/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
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 140ab15..e9d30c3 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -3005,6 +3005,26 @@ static int ufshcd_compose_dev_cmd(struct ufs_hba *hba,
 }
 
 /*
+ * 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.
  * @hba: per adapter instance
@@ -3012,8 +3032,23 @@ 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);
@@ -7384,6 +7419,20 @@ 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 */
@@ -7449,13 +7498,16 @@ 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 */
@@ -7480,7 +7532,8 @@ 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);
@@ -7506,6 +7559,9 @@ 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__);
-- 
2.7.4