[RFC PATCH v3 1/5] ufs: mcq: Add supporting functions for mcq abort

[RFC PATCH v3 1/5] ufs: mcq: Add supporting functions for mcq abort

[Bao D. Nguyen]

Add supporting functions to handle ufs abort in mcq mode.

Signed-off-by: Bao D. Nguyen <quic_nguyenb@quicinc.com>
---
 drivers/ufs/core/ufs-mcq.c     | 189 +++++++++++++++++++++++++++++++++++++++++
 drivers/ufs/core/ufshcd-priv.h |  10 +++
 drivers/ufs/core/ufshcd.c      |   4 +-
 include/ufs/ufshci.h           |  17 ++++
 4 files changed, 218 insertions(+), 2 deletions(-)

diff --git a/drivers/ufs/core/ufs-mcq.c b/drivers/ufs/core/ufs-mcq.c
index 31df052..29d0e37 100644
--- a/drivers/ufs/core/ufs-mcq.c
+++ b/drivers/ufs/core/ufs-mcq.c
@@ -12,6 +12,9 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include "ufshcd-priv.h"
+#include <linux/delay.h>
+#include <scsi/scsi_cmnd.h>
+#include <linux/bitfield.h>
 
 #define MAX_QUEUE_SUP GENMASK(7, 0)
 #define UFS_MCQ_MIN_RW_QUEUES 2
@@ -27,6 +30,9 @@
 #define MCQ_ENTRY_SIZE_IN_DWORD	8
 #define CQE_UCD_BA GENMASK_ULL(63, 7)
 
+/* Max mcq register polling time in millisecond unit */
+#define MCQ_POLL_MS 500
+
 static int rw_queue_count_set(const char *val, const struct kernel_param *kp)
 {
 	return param_set_uint_minmax(val, kp, UFS_MCQ_MIN_RW_QUEUES,
@@ -429,3 +435,186 @@ int ufshcd_mcq_init(struct ufs_hba *hba)
 	host->host_tagset = 1;
 	return 0;
 }
+
+static int ufshcd_mcq_poll_register(void __iomem *reg, u32 mask,
+			u32 val, unsigned long timeout_ms)
+{
+	unsigned long timeout = jiffies + msecs_to_jiffies(timeout_ms);
+	int err = 0;
+
+	/* ignore bits that we don't intend to wait on */
+	val = val & mask;
+
+	while ((readl(reg) & mask) != val) {
+		usleep_range(10, 50);
+		if (time_after(jiffies, timeout)) {
+			err = -ETIMEDOUT;
+			break;
+		}
+	}
+
+	return err;
+}
+
+static int ufshcd_mcq_sq_stop(struct ufs_hba *hba, struct ufs_hw_queue *hwq)
+{
+	void __iomem *reg;
+	u32 i = hwq->id;
+	int err;
+
+	writel(SQ_STOP, mcq_opr_base(hba, OPR_SQD, i) + REG_SQRTC);
+	reg = mcq_opr_base(hba, OPR_SQD, i) + REG_SQRTS;
+	err = ufshcd_mcq_poll_register(reg, SQ_STS, SQ_STS, MCQ_POLL_MS);
+	if (err)
+		dev_err(hba->dev, "%s: failed. hwq-id=%d, err=%d\n",
+			__func__, i, err);
+	return err;
+}
+
+static int ufshcd_mcq_sq_start(struct ufs_hba *hba, struct ufs_hw_queue *hwq)
+{
+	void __iomem *reg;
+	u32 i = hwq->id;
+	int err;
+
+	writel(SQ_START, mcq_opr_base(hba, OPR_SQD, i) + REG_SQRTC);
+	reg = mcq_opr_base(hba, OPR_SQD, i) + REG_SQRTS;
+	err = ufshcd_mcq_poll_register(reg, SQ_STS, 0, MCQ_POLL_MS);
+	if (err)
+		dev_err(hba->dev, "%s: failed. hwq-id=%d, err=%d\n",
+			__func__, i, err);
+	return err;
+}
+
+/**
+ * ufshcd_mcq_sq_cleanup - Clean up Submission Queue resources
+ * associated with the pending command.
+ * @hba - per adapter instance.
+ * @task_tag - The command's task tag.
+ * @result - Result of the Clean up operation.
+ *
+ * Returns 0 and result on completion. Returns error code if
+ * the operation fails.
+ */
+int ufshcd_mcq_sq_cleanup(struct ufs_hba *hba, int task_tag, int *result)
+{
+	struct ufshcd_lrb *lrbp = &hba->lrb[task_tag];
+	struct scsi_cmnd *cmd = lrbp->cmd;
+	struct ufs_hw_queue *hwq;
+	void __iomem *reg, *opr_sqd_base;
+	u32 nexus, i;
+	int err;
+
+	if (task_tag != hba->nutrs - UFSHCD_NUM_RESERVED) {
+		if (!cmd)
+			return FAILED;
+		hwq = ufshcd_mcq_req_to_hwq(hba, scsi_cmd_to_rq(cmd));
+	} else {
+		hwq = hba->dev_cmd_queue;
+	}
+
+	i = hwq->id;
+
+	spin_lock(&hwq->sq_lock);
+
+	/* stop the SQ fetching before working on it */
+	err = ufshcd_mcq_sq_stop(hba, hwq);
+	if (err)
+		goto unlock;
+
+	/* SQCTI = EXT_IID, IID, LUN, Task Tag */
+	nexus = lrbp->lun << 8 | task_tag;
+	opr_sqd_base = mcq_opr_base(hba, OPR_SQD, i);
+	writel(nexus, opr_sqd_base + REG_SQCTI);
+
+	/* SQRTCy.ICU = 1 */
+	writel(SQ_ICU, opr_sqd_base + REG_SQRTC);
+
+	/* Poll SQRTSy.CUS = 1. Return result from SQRTSy.RTC */
+	reg = opr_sqd_base + REG_SQRTS;
+	err = ufshcd_mcq_poll_register(reg, SQ_CUS, SQ_CUS, MCQ_POLL_MS);
+	if (err) {
+		dev_err(hba->dev, "%s: failed. hwq=%d, lun=0x%x, tag=%d\n",
+			__func__, i, lrbp->lun, task_tag);
+		*result = FIELD_GET(SQ_ICU_ERR_CODE_MASK, readl(reg));
+	}
+
+	err = ufshcd_mcq_sq_start(hba, hwq);
+
+unlock:
+	spin_unlock(&hwq->sq_lock);
+	return err;
+}
+
+static u64 ufshcd_mcq_get_cmd_desc_addr(struct ufs_hba *hba,
+					int task_tag)
+{
+	struct ufshcd_lrb *lrbp = &hba->lrb[task_tag];
+	__le32 hi = lrbp->utr_descriptor_ptr->command_desc_base_addr_hi;
+	__le32 lo = lrbp->utr_descriptor_ptr->command_desc_base_addr_lo;
+
+	return le64_to_cpu((__le64)hi << 32 | lo);
+}
+
+/**
+ * ufshcd_mcq_nullify_cmd - Nullify utrd. Host controller does not fetch
+ * transfer with Command Type = 0xF. post the Completion Queue with OCS=ABORTED.
+ * @hba - per adapter instance.
+ * @hwq - Hardware Queue of the nullified utrd.
+ */
+static void ufshcd_mcq_nullify_cmd(struct ufs_hba *hba, struct ufs_hw_queue *hwq)
+{
+	struct utp_transfer_req_desc *utrd;
+	u32 dword_0;
+
+	utrd = (struct utp_transfer_req_desc *)(hwq->sqe_base_addr +
+			hwq->id * sizeof(struct utp_transfer_req_desc));
+	dword_0 = le32_to_cpu(utrd->header.dword_0);
+	dword_0 &= ~UPIU_COMMAND_TYPE_MASK;
+	dword_0 |= FIELD_PREP(UPIU_COMMAND_TYPE_MASK, 0xF);
+	utrd->header.dword_0 = cpu_to_le32(dword_0);
+}
+
+/**
+ * ufshcd_mcq_sqe_search - Search for the cmd in the Submission Queue (SQ)
+ * @hba - per adapter instance.
+ * @hwq - Hardware Queue to be searched.
+ * @task_tag - The command's task tag.
+ *
+ * Returns true if the SQE containing the command is present in the SQ
+ * (not fetched by the controller); returns false if the SQE is not in the SQ.
+ */
+static bool ufshcd_mcq_sqe_search(struct ufs_hba *hba,
+		struct ufs_hw_queue *hwq, int task_tag)
+{
+	struct utp_transfer_req_desc *utrd;
+	u32 mask = hwq->max_entries - 1;
+	bool ret = false;
+	u64 addr, match;
+	u32 sq_head_slot;
+
+	spin_lock(&hwq->sq_lock);
+
+	ufshcd_mcq_sq_stop(hba, hwq);
+	sq_head_slot = ufshcd_mcq_get_sq_head_slot(hwq);
+	if (sq_head_slot == hwq->sq_tail_slot)
+		goto out;
+
+	addr = ufshcd_mcq_get_cmd_desc_addr(hba, task_tag);
+	while (sq_head_slot != hwq->sq_tail_slot) {
+		utrd = (struct utp_transfer_req_desc *)(hwq->sqe_base_addr +
+				sq_head_slot * sizeof(struct utp_transfer_req_desc));
+		match = le64_to_cpu((__le64)utrd->command_desc_base_addr_hi << 32 |
+				utrd->command_desc_base_addr_lo) & CQE_UCD_BA;
+		if (addr == match) {
+			ret = true;
+			goto out;
+		}
+		sq_head_slot = (sq_head_slot + 1) & mask;
+	}
+
+out:
+	ufshcd_mcq_sq_start(hba, hwq);
+	spin_unlock(&hwq->sq_lock);
+	return ret;
+}
diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index 529f850..1a40cf7 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -78,6 +78,8 @@ 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);
 
+int ufshcd_mcq_sq_cleanup(struct ufs_hba *hba, int task_tag, int *result);
+
 #define UFSHCD_MCQ_IO_QUEUE_OFFSET	1
 #define SD_ASCII_STD true
 #define SD_RAW false
@@ -403,4 +405,12 @@ static inline struct cq_entry *ufshcd_mcq_cur_cqe(struct ufs_hw_queue *q)
 
 	return cqe + q->cq_head_slot;
 }
+
+static inline u32 ufshcd_mcq_get_sq_head_slot(struct ufs_hw_queue *q)
+{
+	u32 val = readl(q->mcq_sq_head);
+
+	return val / sizeof(struct utp_transfer_req_desc);
+}
+
 #endif /* _UFSHCD_PRIV_H_ */
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 629442c..504f041 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -56,7 +56,8 @@
 #define NOP_OUT_RETRIES    10
 /* Timeout after 50 msecs if NOP OUT hangs without response */
 #define NOP_OUT_TIMEOUT    50 /* msecs */
-
+/* Maximum MCQ registers polling time */
+#define MCQ_POLL_TIMEOUT   500
 /* Query request retries */
 #define QUERY_REQ_RETRIES 3
 /* Query request timeout */
@@ -173,7 +174,6 @@ EXPORT_SYMBOL_GPL(ufshcd_dump_regs);
 enum {
 	UFSHCD_MAX_CHANNEL	= 0,
 	UFSHCD_MAX_ID		= 1,
-	UFSHCD_NUM_RESERVED	= 1,
 	UFSHCD_CMD_PER_LUN	= 32 - UFSHCD_NUM_RESERVED,
 	UFSHCD_CAN_QUEUE	= 32 - UFSHCD_NUM_RESERVED,
 };
diff --git a/include/ufs/ufshci.h b/include/ufs/ufshci.h
index 11424bb..ceb8664 100644
--- a/include/ufs/ufshci.h
+++ b/include/ufs/ufshci.h
@@ -99,6 +99,9 @@ enum {
 enum {
 	REG_SQHP		= 0x0,
 	REG_SQTP		= 0x4,
+	REG_SQRTC		= 0x8,
+	REG_SQCTI		= 0xC,
+	REG_SQRTS		= 0x10,
 };
 
 enum {
@@ -111,12 +114,26 @@ enum {
 	REG_CQIE		= 0x4,
 };
 
+enum {
+	SQ_START		= 0x0,
+	SQ_STOP			= 0x1,
+	SQ_ICU			= 0x2,
+};
+
+enum {
+	SQ_STS			= 0x1,
+	SQ_CUS			= 0x2,
+};
+
+#define SQ_ICU_ERR_CODE_MASK		GENMASK(7, 4)
+#define UPIU_COMMAND_TYPE_MASK		GENMASK(31, 28)
 #define UFS_MASK(mask, offset)		((mask) << (offset))
 
 /* UFS Version 08h */
 #define MINOR_VERSION_NUM_MASK		UFS_MASK(0xFFFF, 0)
 #define MAJOR_VERSION_NUM_MASK		UFS_MASK(0xFFFF, 16)
 
+#define UFSHCD_NUM_RESERVED	1
 /*
  * Controller UFSHCI version
  * - 2.x and newer use the following scheme:
-- 
2.7.4

[RFC PATCH v3 2/5] ufs: mcq: Add support for clean up mcq resources

[Bao D. Nguyen]

Update ufshcd_clear_cmds() 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.c | 41 +++++++++++++++++++++++++++++++++++++----
 1 file changed, 37 insertions(+), 4 deletions(-)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 504f041..0ecd03e 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -2984,10 +2984,28 @@ static int ufshcd_compose_dev_cmd(struct ufs_hba *hba,
  * @mask and wait until the controller confirms that these requests have been
  * cleared.
  */
-static int ufshcd_clear_cmds(struct ufs_hba *hba, u32 mask)
+static int ufshcd_clear_cmds(struct ufs_hba *hba, unsigned long mask)
 {
 	unsigned long flags;
+	int err, result, tag;
 
+	if (is_mcq_enabled(hba)) {
+		/*
+		 * MCQ mode. Clean up the MCQ resources similar to
+		 * what the ufshcd_utrl_clear() does for SDB mode.
+		 */
+		for_each_set_bit(tag, &mask, hba->nutrs) {
+			err = ufshcd_mcq_sq_cleanup(hba, tag, &result);
+			if (err || result) {
+				dev_err(hba->dev, "%s: failed tag=%d. err=%d, result=%d\n",
+					__func__, tag, err, result);
+				return FAILED;
+			}
+		}
+		return 0;
+	}
+
+	/* Single Doorbell Mode */
 	/* clear outstanding transaction before retry */
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	ufshcd_utrl_clear(hba, mask);
@@ -7343,6 +7361,20 @@ 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 (lrbp->cmd) {
+					/* sleep for max. 200us to stabilize */
+					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 door bell mode */
 			reg = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
 			if (reg & (1 << tag)) {
 				/* sleep for max. 200us to stabilize */
@@ -7409,8 +7441,8 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 
 	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))) {
+	if (!is_mcq_enabled(hba) && !(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);
@@ -7439,7 +7471,8 @@ 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);
-- 
2.7.4

[RFC PATCH v3 3/5] ufs: mcq: Added ufshcd_mcq_abort()

[Bao D. Nguyen]

Add ufshcd_mcq_abort() to support ufs abort in mcq mode.

Signed-off-by: Bao D. Nguyen <quic_nguyenb@quicinc.com>
---
 drivers/ufs/core/ufs-mcq.c     | 62 ++++++++++++++++++++++++++++++++++++++++++
 drivers/ufs/core/ufshcd-priv.h |  5 +++-
 drivers/ufs/core/ufshcd.c      | 11 ++++++--
 3 files changed, 74 insertions(+), 4 deletions(-)

diff --git a/drivers/ufs/core/ufs-mcq.c b/drivers/ufs/core/ufs-mcq.c
index 29d0e37..5c417a1 100644
--- a/drivers/ufs/core/ufs-mcq.c
+++ b/drivers/ufs/core/ufs-mcq.c
@@ -618,3 +618,65 @@ static bool ufshcd_mcq_sqe_search(struct ufs_hba *hba,
 	spin_unlock(&hwq->sq_lock);
 	return ret;
 }
+
+/**
+ * ufshcd_mcq_abort - Abort the command in MCQ.
+ * @cmd - The command to be aborted.
+ *
+ * Returns SUCCESS or FAILED error codes
+ */
+int ufshcd_mcq_abort(struct scsi_cmnd *cmd)
+{
+	struct Scsi_Host *host = cmd->device->host;
+	struct ufs_hba *hba = shost_priv(host);
+	int tag = scsi_cmd_to_rq(cmd)->tag;
+	struct ufshcd_lrb *lrbp = &hba->lrb[tag];
+	struct ufs_hw_queue *hwq;
+	int err = FAILED;
+
+	if (!lrbp->cmd) {
+		dev_err(hba->dev,
+			"%s: skip abort. cmd at tag %d already completed.\n",
+			__func__, tag);
+		goto out;
+	}
+
+	/* Skip task abort in case previous aborts failed and report failure */
+	if (lrbp->req_abort_skip) {
+		dev_err(hba->dev, "%s: skip abort. tag %d failed earlier\n",
+			__func__, tag);
+		goto out;
+	}
+
+	hwq = ufshcd_mcq_req_to_hwq(hba, scsi_cmd_to_rq(cmd));
+
+	if (ufshcd_mcq_sqe_search(hba, hwq, tag)) {
+		/*
+		 * Failure. The command should not be "stuck" in SQ for
+		 * a long time which resulted in command being aborted.
+		 */
+		dev_err(hba->dev, "%s: cmd found in sq. hwq=%d, tag=%d\n",
+				__func__, hwq->id, tag);
+		/* Set the Command Type to 0xF per the spec */
+		ufshcd_mcq_nullify_cmd(hba, hwq);
+		goto out;
+	}
+
+	/*
+	 * The command is not in the Submission Queue, and it is not
+	 * in the Completion Queue either. Query the device to see if
+	 * the command is being processed in the device.
+	 */
+	if (ufshcd_try_to_abort_task(hba, tag)) {
+		dev_err(hba->dev, "%s: device abort failed %d\n", __func__, err);
+		lrbp->req_abort_skip = true;
+		goto out;
+	}
+
+	err = SUCCESS;
+	if (lrbp->cmd)
+		ufshcd_release_scsi_cmd(hba, lrbp);
+
+out:
+	return err;
+}
diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index 1a40cf7..ef66151 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -79,7 +79,10 @@ unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
 				       struct ufs_hw_queue *hwq);
 
 int ufshcd_mcq_sq_cleanup(struct ufs_hba *hba, int task_tag, int *result);
-
+int ufshcd_mcq_abort(struct scsi_cmnd *cmd);
+int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag);
+void ufshcd_release_scsi_cmd(struct ufs_hba *hba,
+				struct ufshcd_lrb *lrbp);
 #define UFSHCD_MCQ_IO_QUEUE_OFFSET	1
 #define SD_ASCII_STD true
 #define SD_RAW false
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 0ecd03e..359747a 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -301,7 +301,6 @@ static int ufshcd_setup_hba_vreg(struct ufs_hba *hba, bool on);
 static int ufshcd_setup_vreg(struct ufs_hba *hba, bool on);
 static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
 					 struct ufs_vreg *vreg);
-static int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag);
 static void ufshcd_wb_toggle_buf_flush_during_h8(struct ufs_hba *hba,
 						 bool enable);
 static void ufshcd_hba_vreg_set_lpm(struct ufs_hba *hba);
@@ -5412,7 +5411,7 @@ static irqreturn_t ufshcd_uic_cmd_compl(struct ufs_hba *hba, u32 intr_status)
 }
 
 /* Release the resources allocated for processing a SCSI command. */
-static void ufshcd_release_scsi_cmd(struct ufs_hba *hba,
+void ufshcd_release_scsi_cmd(struct ufs_hba *hba,
 				    struct ufshcd_lrb *lrbp)
 {
 	struct scsi_cmnd *cmd = lrbp->cmd;
@@ -7338,7 +7337,7 @@ static void ufshcd_set_req_abort_skip(struct ufs_hba *hba, unsigned long bitmap)
  *
  * Returns zero on success, non-zero on failure
  */
-static int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag)
+int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag)
 {
 	struct ufshcd_lrb *lrbp = &hba->lrb[tag];
 	int err = 0;
@@ -7498,6 +7497,12 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 		goto release;
 	}
 
+	if (is_mcq_enabled(hba)) {
+		/* MCQ mode. Branch off to handle abort for mcq mode */
+		err = ufshcd_mcq_abort(cmd);
+		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

[RFC PATCH v3 4/5] ufs: mcq: Use ufshcd_mcq_poll_cqe_lock() in mcq mode

[Bao D. Nguyen]

In preparation for adding mcq error handler support, update the mcq
code to use the ufshcd_mcq_poll_cqe_lock() in interrupt context
instead of using ufshcd_mcq_poll_cqe_nolock(). This is to keep
synchronization between mcq interrupt and error handler contexts
because both need to access the mcq hardware in separate contexts.

Signed-off-by: Bao D. Nguyen <quic_nguyenb@quicinc.com>
---
 drivers/ufs/core/ufs-mcq.c     | 6 +++---
 drivers/ufs/core/ufshcd-priv.h | 2 --
 drivers/ufs/core/ufshcd.c      | 2 +-
 drivers/ufs/host/ufs-qcom.c    | 2 +-
 include/ufs/ufshcd.h           | 2 +-
 5 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/ufs/core/ufs-mcq.c b/drivers/ufs/core/ufs-mcq.c
index 5c417a1..613d302 100644
--- a/drivers/ufs/core/ufs-mcq.c
+++ b/drivers/ufs/core/ufs-mcq.c
@@ -283,8 +283,8 @@ static void ufshcd_mcq_process_cqe(struct ufs_hba *hba,
 	ufshcd_compl_one_cqe(hba, tag, cqe);
 }
 
-unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
-					 struct ufs_hw_queue *hwq)
+static unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
+						struct ufs_hw_queue *hwq)
 {
 	unsigned long completed_reqs = 0;
 
@@ -300,7 +300,6 @@ unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
 
 	return completed_reqs;
 }
-EXPORT_SYMBOL_GPL(ufshcd_mcq_poll_cqe_nolock);
 
 unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
 				       struct ufs_hw_queue *hwq)
@@ -313,6 +312,7 @@ unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
 
 	return completed_reqs;
 }
+EXPORT_SYMBOL_GPL(ufshcd_mcq_poll_cqe_lock);
 
 void ufshcd_mcq_make_queues_operational(struct ufs_hba *hba)
 {
diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index ef66151..70b7ffc 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -71,8 +71,6 @@ void ufshcd_mcq_config_mac(struct ufs_hba *hba, u32 max_active_cmds);
 void ufshcd_mcq_select_mcq_mode(struct ufs_hba *hba);
 u32 ufshcd_mcq_read_cqis(struct ufs_hba *hba, int i);
 void ufshcd_mcq_write_cqis(struct ufs_hba *hba, u32 val, int i);
-unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
-					 struct ufs_hw_queue *hwq);
 struct ufs_hw_queue *ufshcd_mcq_req_to_hwq(struct ufs_hba *hba,
 					   struct request *req);
 unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 359747a..3c28627 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -6756,7 +6756,7 @@ static irqreturn_t ufshcd_handle_mcq_cq_events(struct ufs_hba *hba)
 			ufshcd_mcq_write_cqis(hba, events, i);
 
 		if (events & UFSHCD_MCQ_CQIS_TAIL_ENT_PUSH_STS)
-			ufshcd_mcq_poll_cqe_nolock(hba, hwq);
+			ufshcd_mcq_poll_cqe_lock(hba, hwq);
 	}
 
 	return IRQ_HANDLED;
diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
index 34fc453..c686fb8 100644
--- a/drivers/ufs/host/ufs-qcom.c
+++ b/drivers/ufs/host/ufs-qcom.c
@@ -1558,7 +1558,7 @@ static irqreturn_t ufs_qcom_mcq_esi_handler(int irq, void *__hba)
 	struct ufs_hw_queue *hwq = &hba->uhq[id];
 
 	ufshcd_mcq_write_cqis(hba, 0x1, id);
-	ufshcd_mcq_poll_cqe_nolock(hba, hwq);
+	ufshcd_mcq_poll_cqe_lock(hba, hwq);
 
 	return IRQ_HANDLED;
 }
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index 05e4164..5d7f9b2 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -1244,7 +1244,7 @@ void ufshcd_update_evt_hist(struct ufs_hba *hba, u32 id, u32 val);
 void ufshcd_hba_stop(struct ufs_hba *hba);
 void ufshcd_schedule_eh_work(struct ufs_hba *hba);
 void ufshcd_mcq_write_cqis(struct ufs_hba *hba, u32 val, int i);
-unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
+unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
 					 struct ufs_hw_queue *hwq);
 void ufshcd_mcq_enable_esi(struct ufs_hba *hba);
 void ufshcd_mcq_config_esi(struct ufs_hba *hba, struct msi_msg *msg);
-- 
2.7.4

[RFC PATCH v3 5/5] ufs: core: Add error handling for MCQ mode

[Bao D. Nguyen]

Add support for error handling for MCQ mode.

Signed-off-by: Bao D. Nguyen <quic_nguyenb@quicinc.com>
---
 drivers/ufs/core/ufshcd.c | 81 ++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 70 insertions(+), 11 deletions(-)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 3c28627..be4299e 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -3104,6 +3104,12 @@ 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))
+			return ufshcd_clear_cmds(hba, 1U << lrbp->task_tag);
+
+		/* SDB mode */
 		if (ufshcd_clear_cmds(hba, 1U << lrbp->task_tag) == 0) {
 			/* successfully cleared the command, retry if needed */
 			err = -EAGAIN;
@@ -5536,6 +5542,10 @@ 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
@@ -5554,7 +5564,22 @@ 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 (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);
+		}
+	}
+
+out:
 
 	return IRQ_HANDLED;
 }
@@ -6323,18 +6348,36 @@ static bool ufshcd_abort_all(struct ufs_hba *hba)
 	bool needs_reset = false;
 	int tag, ret;
 
-	/* Clear pending transfer requests */
-	for_each_set_bit(tag, &hba->outstanding_reqs, hba->nutrs) {
-		ret = ufshcd_try_to_abort_task(hba, tag);
-		dev_err(hba->dev, "Aborting tag %d / CDB %#02x %s\n", tag,
-			hba->lrb[tag].cmd ? hba->lrb[tag].cmd->cmnd[0] : -1,
-			ret ? "failed" : "succeeded");
-		if (ret) {
-			needs_reset = true;
-			goto out;
+	if (is_mcq_enabled(hba)) {
+		struct ufshcd_lrb *lrbp;
+		int tag;
+
+		for (tag = 0; tag < hba->nutrs; tag++) {
+			lrbp = &hba->lrb[tag];
+			if (lrbp->cmd) {
+				ret = ufshcd_try_to_abort_task(hba, tag);
+				dev_err(hba->dev, "Aborting tag %d / CDB %#02x %s\n", tag,
+					hba->lrb[tag].cmd ? hba->lrb[tag].cmd->cmnd[0] : -1,
+					ret ? "failed" : "succeeded");
+			}
+			if (ret) {
+				needs_reset = true;
+				goto out;
+			}
+		}
+	} else {
+		/* Clear pending transfer requests */
+		for_each_set_bit(tag, &hba->outstanding_reqs, hba->nutrs) {
+			ret = ufshcd_try_to_abort_task(hba, tag);
+			dev_err(hba->dev, "Aborting tag %d / CDB %#02x %s\n", tag,
+				hba->lrb[tag].cmd ? hba->lrb[tag].cmd->cmnd[0] : -1,
+				ret ? "failed" : "succeeded");
+			if (ret) {
+				needs_reset = true;
+				goto out;
+			}
 		}
 	}
-
 	/* Clear pending task management requests */
 	for_each_set_bit(tag, &hba->outstanding_tasks, hba->nutmrs) {
 		if (ufshcd_clear_tm_cmd(hba, tag)) {
@@ -7266,6 +7309,8 @@ static int ufshcd_eh_device_reset_handler(struct scsi_cmnd *cmd)
 	unsigned long flags, pending_reqs = 0, not_cleared = 0;
 	struct Scsi_Host *host;
 	struct ufs_hba *hba;
+	struct ufs_hw_queue *hwq;
+	struct ufshcd_lrb *lrbp;
 	u32 pos;
 	int err;
 	u8 resp = 0xF, lun;
@@ -7281,6 +7326,20 @@ static int ufshcd_eh_device_reset_handler(struct scsi_cmnd *cmd)
 		goto out;
 	}
 
+	if (is_mcq_enabled(hba)) {
+		for (pos = 0; pos < hba->nutrs; pos++) {
+			lrbp = &hba->lrb[pos];
+			if (lrbp->cmd && lrbp->lun == lun) {
+				ufshcd_clear_cmds(hba, 1U << pos);
+				hwq = ufshcd_mcq_req_to_hwq(hba,
+					scsi_cmd_to_rq(lrbp->cmd));
+				ufshcd_mcq_poll_cqe_lock(hba, hwq);
+			}
+		}
+		err = 0;
+		goto out;
+	}
+
 	/* clear the commands that were pending for corresponding LUN */
 	spin_lock_irqsave(&hba->outstanding_lock, flags);
 	for_each_set_bit(pos, &hba->outstanding_reqs, hba->nutrs)
-- 
2.7.4

Re: [RFC PATCH v3 1/5] ufs: mcq: Add supporting functions for mcq abort

[John Garry]

On 23/03/2023 09:53, Bao D. Nguyen wrote:
> +static int ufshcd_mcq_poll_register(void __iomem *reg, u32 mask,
> +			u32 val, unsigned long timeout_ms)
> +{
> +	unsigned long timeout = jiffies + msecs_to_jiffies(timeout_ms);
> +	int err = 0;
> +
> +	/* ignore bits that we don't intend to wait on */
> +	val = val & mask;
> +
> +	while ((readl(reg) & mask) != val) {
> +		usleep_range(10, 50);
> +		if (time_after(jiffies, timeout)) {
> +			err = -ETIMEDOUT;
> +			break;
> +		}

This looks just like readl_poll_timeout()

> +	}
> +
> +	return err;
> +}

Re: [RFC PATCH v3 1/5] ufs: mcq: Add supporting functions for mcq abort

[Bao D. Nguyen]

On 3/23/2023 3:07 AM, John Garry wrote:
> On 23/03/2023 09:53, Bao D. Nguyen wrote:
>> +static int ufshcd_mcq_poll_register(void __iomem *reg, u32 mask,
>> +            u32 val, unsigned long timeout_ms)
>> +{
>> +    unsigned long timeout = jiffies + msecs_to_jiffies(timeout_ms);
>> +    int err = 0;
>> +
>> +    /* ignore bits that we don't intend to wait on */
>> +    val = val & mask;
>> +
>> +    while ((readl(reg) & mask) != val) {
>> +        usleep_range(10, 50);
>> +        if (time_after(jiffies, timeout)) {
>> +            err = -ETIMEDOUT;
>> +            break;
>> +        }
>
> This looks just like readl_poll_timeout()
I will make the change in the next revision. Thanks John.
>
>> +    }
>> +
>> +    return err;
>> +}
>