[PATCH 0/2]

drivers/scsi/ufs/ufshcd.c +12 -0

+/*
+ * ufshcd_wait_for_register - wait for register value to change
+ * @hba - per-adapter interface
+ * @reg - mmio register offset
+ * @mask - mask to apply to read register value
+ * @val - wait condition
+ * @interval_us - polling interval in microsecs
+ * @timeout_ms - timeout in millisecs
+ *
+ * Returns final register value after iteration
+ */
+static u32 ufshcd_wait_for_register(struct ufs_hba *hba, u32 reg, u32 mask,

drivers/scsi/ufs/ufshcd.c +364 -108

+                       break;
+               }
+       }
+
+       return tmp;
+}
+
 /**
  * ufshcd_get_intr_mask - Get the interrupt bit mask
  * @hba - Pointer to adapter instance

@@ -223,18 +267,13 @@ static inline void ufshcd_free_hba_memory(struct ufs_hba *hba)
 }
 
 /**
- * ufshcd_is_valid_req_rsp - checks if controller TR response is valid
+ * ufshcd_get_req_rsp - returns the TR response
  * @ucd_rsp_ptr: pointer to response UPIU
- *
- * This function checks the response UPIU for valid transaction type in
- * response field
- * Returns 0 on success, non-zero on failure
  */
 static inline int
-ufshcd_is_valid_req_rsp(struct utp_upiu_rsp *ucd_rsp_ptr)
+ufshcd_get_req_rsp(struct utp_upiu_rsp *ucd_rsp_ptr)
 {
-       return ((be32_to_cpu(ucd_rsp_ptr->header.dword_0) >> 24) ==
-                UPIU_TRANSACTION_RESPONSE) ? 0 : DID_ERROR << 16;
+       return be32_to_cpu(ucd_rsp_ptr->header.dword_0) >> 24;
 }
 
 /**

@@ -331,9 +370,9 @@ static inline void ufshcd_copy_sense_data(struct ufshcd_lrb *lrbp)
 {
        int len;
        if (lrbp->sense_buffer) {
-               len = be16_to_cpu(lrbp->ucd_rsp_ptr->sense_data_len);
+               len = be16_to_cpu(lrbp->ucd_rsp_ptr->sc.sense_data_len);
                memcpy(lrbp->sense_buffer,
-                       lrbp->ucd_rsp_ptr->sense_data,
+                       lrbp->ucd_rsp_ptr->sc.sense_data,
                        min_t(int, len, SCSI_SENSE_BUFFERSIZE));
        }
 }

@@ -551,76 +590,128 @@ static void ufshcd_disable_intr(struct ufs_hba *hba, u32 intrs)
 }
 
 /**
+ * ufshcd_prepare_req_desc() - Fills the requests header
+ * descriptor according to request
+ * @lrbp: pointer to local reference block
+ * @upiu_flags: flags required in the header
+ * @cmd_dir: requests data direction
+ */
+static void ufshcd_prepare_req_desc(struct ufshcd_lrb *lrbp, u32 *upiu_flags,
+               enum dma_data_direction cmd_dir)
+{
+       struct utp_transfer_req_desc *req_desc = lrbp->utr_descriptor_ptr;
+       u32 data_direction;
+       u32 dword_0;
+
+       if (cmd_dir == DMA_FROM_DEVICE) {
+               data_direction = UTP_DEVICE_TO_HOST;
+               *upiu_flags = UPIU_CMD_FLAGS_READ;
+       } else if (cmd_dir == DMA_TO_DEVICE) {
+               data_direction = UTP_HOST_TO_DEVICE;
+               *upiu_flags = UPIU_CMD_FLAGS_WRITE;
+       } else {
+               data_direction = UTP_NO_DATA_TRANSFER;
+               *upiu_flags = UPIU_CMD_FLAGS_NONE;
+       }
+
+       dword_0 = data_direction | (lrbp->command_type
+                               << UPIU_COMMAND_TYPE_OFFSET);
+       if (lrbp->intr_cmd)
+               dword_0 |= UTP_REQ_DESC_INT_CMD;
+
+       /* Transfer request descriptor header fields */
+       req_desc->header.dword_0 = cpu_to_le32(dword_0);
+
+       /*
+        * assigning invalid value for command status. Controller
+        * updates OCS on command completion, with the command
+        * status
+        */
+       req_desc->header.dword_2 =
+               cpu_to_le32(OCS_INVALID_COMMAND_STATUS);
+}
+
+/**
+ * ufshcd_prepare_utp_scsi_cmd_upiu() - fills the utp_transfer_req_desc,
+ * for scsi commands
+ * @lrbp - local reference block pointer
+ * @upiu_flags - flags
+ */
+static
+void ufshcd_prepare_utp_scsi_cmd_upiu(struct ufshcd_lrb *lrbp, u32 upiu_flags)
+{
+       struct utp_upiu_req *ucd_req_ptr = lrbp->ucd_req_ptr;
+
+       /* command descriptor fields */
+       ucd_req_ptr->header.dword_0 = UPIU_HEADER_DWORD(
+                               UPIU_TRANSACTION_COMMAND, upiu_flags,
+                               lrbp->lun, lrbp->task_tag);
+       ucd_req_ptr->header.dword_1 = UPIU_HEADER_DWORD(
+                               UPIU_COMMAND_SET_TYPE_SCSI, 0, 0, 0);
+
+       /* Total EHS length and Data segment length will be zero */
+       ucd_req_ptr->header.dword_2 = 0;
+
+       ucd_req_ptr->sc.exp_data_transfer_len =
+               cpu_to_be32(lrbp->cmd->sdb.length);
+
+       memcpy(ucd_req_ptr->sc.cdb, lrbp->cmd->cmnd,
+               (min_t(unsigned short, lrbp->cmd->cmd_len, MAX_CDB_SIZE)));
+}
+
+static inline void ufshcd_prepare_utp_nop_upiu(struct ufshcd_lrb *lrbp)
+{
+       struct utp_upiu_req *ucd_req_ptr = lrbp->ucd_req_ptr;
+
+       memset(ucd_req_ptr, 0, sizeof(struct utp_upiu_req));
+
+       /* command descriptor fields */
+       ucd_req_ptr->header.dword_0 =
+               UPIU_HEADER_DWORD(
+                       UPIU_TRANSACTION_NOP_OUT, 0, 0, lrbp->task_tag);
+}
+
+/**
  * ufshcd_compose_upiu - form UFS Protocol Information Unit(UPIU)
+ * @hba - per adapter instance
  * @lrb - pointer to local reference block
  */
-static void ufshcd_compose_upiu(struct ufshcd_lrb *lrbp)
+static int ufshcd_compose_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 {
-       struct utp_transfer_req_desc *req_desc;
-       struct utp_upiu_cmd *ucd_cmd_ptr;
-       u32 data_direction;
        u32 upiu_flags;
-
-       ucd_cmd_ptr = lrbp->ucd_cmd_ptr;
-       req_desc = lrbp->utr_descriptor_ptr;
+       int ret = 0;
 
        switch (lrbp->command_type) {
        case UTP_CMD_TYPE_SCSI:
-               if (lrbp->cmd->sc_data_direction == DMA_FROM_DEVICE) {
-                       data_direction = UTP_DEVICE_TO_HOST;
-                       upiu_flags = UPIU_CMD_FLAGS_READ;
-               } else if (lrbp->cmd->sc_data_direction == DMA_TO_DEVICE) {
-                       data_direction = UTP_HOST_TO_DEVICE;
-                       upiu_flags = UPIU_CMD_FLAGS_WRITE;
+               if (likely(lrbp->cmd)) {
+                       ufshcd_prepare_req_desc(lrbp, &upiu_flags,
+                                       lrbp->cmd->sc_data_direction);
+                       ufshcd_prepare_utp_scsi_cmd_upiu(lrbp, upiu_flags);
                } else {
-                       data_direction = UTP_NO_DATA_TRANSFER;
-                       upiu_flags = UPIU_CMD_FLAGS_NONE;
+                       ret = -EINVAL;
                }
-
-               /* Transfer request descriptor header fields */
-               req_desc->header.dword_0 =
-                       cpu_to_le32(data_direction | UTP_SCSI_COMMAND);
-
-               /*
-                * assigning invalid value for command status. Controller
-                * updates OCS on command completion, with the command
-                * status
-                */
-               req_desc->header.dword_2 =
-                       cpu_to_le32(OCS_INVALID_COMMAND_STATUS);
-
-               /* command descriptor fields */
-               ucd_cmd_ptr->header.dword_0 =
-                       cpu_to_be32(UPIU_HEADER_DWORD(UPIU_TRANSACTION_COMMAND,
-                                                     upiu_flags,
-                                                     lrbp->lun,
-                                                     lrbp->task_tag));
-               ucd_cmd_ptr->header.dword_1 =
-                       cpu_to_be32(
-                               UPIU_HEADER_DWORD(UPIU_COMMAND_SET_TYPE_SCSI,
-                                                 0,
-                                                 0,
-                                                 0));
-
-               /* Total EHS length and Data segment length will be zero */
-               ucd_cmd_ptr->header.dword_2 = 0;
-
-               ucd_cmd_ptr->exp_data_transfer_len =
-                       cpu_to_be32(lrbp->cmd->sdb.length);
-
-               memcpy(ucd_cmd_ptr->cdb,
-                      lrbp->cmd->cmnd,
-                      (min_t(unsigned short,
-                             lrbp->cmd->cmd_len,
-                             MAX_CDB_SIZE)));
                break;
        case UTP_CMD_TYPE_DEV_MANAGE:
-               /* For query function implementation */
+               ufshcd_prepare_req_desc(lrbp, &upiu_flags, DMA_NONE);
+               if (hba->i_cmd.dev_cmd_type == DEV_CMD_TYPE_NOP)
+                       ufshcd_prepare_utp_nop_upiu(lrbp);
+               else
+                       ret = -EINVAL;
                break;
        case UTP_CMD_TYPE_UFS:
                /* For UFS native command implementation */
+               dev_err(hba->dev, "%s: UFS native command are not supported\n",
+                       __func__);
+               ret = -ENOTSUPP;
+               break;
+       default:
+               ret = -ENOTSUPP;
+               dev_err(hba->dev, "%s: unknown command type: 0x%x\n",
+                               __func__, lrbp->command_type);
                break;
        } /* end of switch */
+
+       return ret;
 }
 
 /**

@@ -654,11 +745,11 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
        lrbp->sense_buffer = cmd->sense_buffer;
        lrbp->task_tag = tag;
        lrbp->lun = cmd->device->lun;
-
+       lrbp->intr_cmd = false;
        lrbp->command_type = UTP_CMD_TYPE_SCSI;
 
        /* form UPIU before issuing the command */
-       ufshcd_compose_upiu(lrbp);
+       ufshcd_compose_upiu(hba, lrbp);
        err = ufshcd_map_sg(lrbp);
        if (err)
                goto out;

@@ -671,6 +762,139 @@ out:
        return err;
 }
 
+static int ufshcd_compose_internal_cmd(struct ufs_hba *hba,
+               struct ufshcd_lrb *lrbp, enum internal_cmd_type cmd_type)
+{
+       lrbp->cmd = NULL;
+       lrbp->sense_bufflen = 0;
+       lrbp->sense_buffer = NULL;
+       lrbp->task_tag = INTERNAL_CMD_TAG;
+       lrbp->lun = 0; /* internal cmd is not specific to any LUN */
+       lrbp->command_type = UTP_CMD_TYPE_DEV_MANAGE;
+       lrbp->intr_cmd = true; /* No interrupt aggregation */
+       hba->i_cmd.dev_cmd_type = cmd_type;
+
+       return ufshcd_compose_upiu(hba, lrbp);
+}
+
+static int ufshcd_wait_for_internal_cmd(struct ufs_hba *hba,
+               struct ufshcd_lrb *lrbp, int max_timeout)
+{
+       int err = 0;
+       unsigned long timeout;
+       unsigned long flags;
+
+       timeout = wait_for_completion_timeout(hba->i_cmd.dev_cmd_complete,
+                       msecs_to_jiffies(max_timeout));
+
+       spin_lock_irqsave(hba->host->host_lock, flags);
+       hba->i_cmd.dev_cmd_complete = NULL;
+       if (timeout)
+               err = ufshcd_get_tr_ocs(lrbp);
+       else
+               err = -ETIMEDOUT;
+       spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+       return err;
+}
+
+static int
+ufshcd_clear_cmd(struct ufs_hba *hba, int tag)
+{
+       int err = 0;
+       unsigned long flags;
+       u32 reg;
+       u32 mask = 1 << tag;
+
+       /* clear outstanding transaction before retry */
+       spin_lock_irqsave(hba->host->host_lock, flags);
+       ufshcd_utrl_clear(hba, INTERNAL_CMD_TAG);
+       spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+       /* poll for max. 1 sec to clear door bell register by h/w */
+       reg = ufshcd_wait_for_register(hba,
+                       REG_UTP_TRANSFER_REQ_DOOR_BELL,
+                       mask, mask, 1000, 1000);
+       if ((reg & mask) == mask)
+               err = -ETIMEDOUT;
+
+       return err;
+}
+
+/**
+ * ufshcd_internal_cmd_completion() - handles internal command responses
+ * @hba: per adapter instance
+ * @lrbp: pointer to local reference block
+ */
+static int
+ufshcd_internal_cmd_completion(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+       int resp;
+       int err = 0;
+
+       resp = ufshcd_get_req_rsp(lrbp->ucd_rsp_ptr);
+
+       switch (resp) {
+       case UPIU_TRANSACTION_NOP_IN:
+               break;
+       case UPIU_TRANSACTION_REJECT_UPIU:
+               /* TODO: handle Reject UPIU Response */
+               dev_err(hba->dev, "Reject UPIU not fully implemented\n");
+               err = -EPERM;
+               break;
+       default:
+               dev_err(hba->dev, "Invalid internal cmd response: %x\n", resp);
+               err = -EINVAL;
+               break;
+       }
+
+       return err;
+}
+
+/**
+ * ufshcd_exec_internal_cmd() - API for sending internal
+ * requests
+ * @hba - UFS hba
+ * @cmd_type - specifies the type (NOP, Query...)
+ * @timeout - time in seconds
+ *
+ * NOTE: There is only one available tag for internal commands. Thus
+ * synchronisation is the responsibilty of the user.
+ */
+static int ufshcd_exec_internal_cmd(struct ufs_hba *hba,
+               enum internal_cmd_type cmd_type, int timeout)
+{
+       struct ufshcd_lrb *lrbp;
+       int err;
+       struct completion wait;
+       unsigned long flags;
+
+       init_completion(&wait);
+       lrbp = &hba->lrb[INTERNAL_CMD_TAG];
+
+       err = ufshcd_compose_internal_cmd(hba, lrbp, cmd_type);
+       if (unlikely(err))
+               goto out;
+
+       hba->i_cmd.dev_cmd_complete = &wait;
+
+       spin_lock_irqsave(hba->host->host_lock, flags);
+       ufshcd_send_command(hba, INTERNAL_CMD_TAG);
+       spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+       err = ufshcd_wait_for_internal_cmd(hba, lrbp, timeout);
+
+       if (err == -ETIMEDOUT) {
+               if (!ufshcd_clear_cmd(hba, INTERNAL_CMD_TAG))
+                       err = -EAGAIN;
+       } else if (!err) {
+               err = ufshcd_internal_cmd_completion(hba, lrbp);
+       }
+
+out:
+       return err;
+}
+
 /**
  * ufshcd_memory_alloc - allocate memory for host memory space data structures
  * @hba: per adapter instance

@@ -805,8 +1029,8 @@ static void ufshcd_host_memory_configure(struct ufs_hba *hba)
                                cpu_to_le16(ALIGNED_UPIU_SIZE);
 
                hba->lrb[i].utr_descriptor_ptr = (utrdlp + i);
-               hba->lrb[i].ucd_cmd_ptr =
-                       (struct utp_upiu_cmd *)(cmd_descp + i);
+               hba->lrb[i].ucd_req_ptr =
+                       (struct utp_upiu_req *)(cmd_descp + i);
                hba->lrb[i].ucd_rsp_ptr =
                        (struct utp_upiu_rsp *)cmd_descp[i].response_upiu;
                hba->lrb[i].ucd_prdt_ptr =

@@ -992,6 +1216,38 @@ out:
 }
 
 /**
+ * ufshcd_validate_dev_connection() - Check device connection status
+ * @hba: per-adapter instance
+ *
+ * Send NOP OUT UPIU and wait for NOP IN response to check whether the
+ * device Transport Protocol (UTP) layer is ready after a reset.
+ * If the UTP layer at the device side is not initialized, it may
+ * not respond with NOP IN UPIU within timeout of %NOP_OUT_TIMEOUT
+ * and we retry sending NOP OUT for %NOP_OUT_RETRIES iterations.
+ */
+static int ufshcd_validate_dev_connection(struct ufs_hba *hba)
+{
+       int err = 0;
+       int retries;
+
+       for (retries = NOP_OUT_RETRIES; retries > 0; retries--) {
+               mutex_lock(&hba->i_cmd.dev_cmd_lock);
+               err = ufshcd_exec_internal_cmd(hba, DEV_CMD_TYPE_NOP,
+                                              NOP_OUT_TIMEOUT);
+               mutex_unlock(&hba->i_cmd.dev_cmd_lock);
+
+               if (!err || err == -ETIMEDOUT)
+                       break;
+
+               dev_dbg(hba->dev, "%s: error %d retrying\n", __func__, err);
+       }
+
+       if (err)
+               dev_err(hba->dev, "%s: NOP OUT failed %d\n", __func__, err);
+       return err;
+}
+
+/**
  * ufshcd_do_reset - reset the host controller
  * @hba: per adapter instance
  *

@@ -1014,16 +1270,22 @@ static int ufshcd_do_reset(struct ufs_hba *hba)
        spin_unlock_irqrestore(hba->host->host_lock, flags);
 
        /* abort outstanding commands */
-       for (tag = 0; tag < hba->nutrs; tag++) {
+       for (tag = 0; tag < SCSI_CMD_QUEUE_SIZE; tag++) {
                if (test_bit(tag, &hba->outstanding_reqs)) {
                        lrbp = &hba->lrb[tag];
-                       scsi_dma_unmap(lrbp->cmd);
-                       lrbp->cmd->result = DID_RESET << 16;
-                       lrbp->cmd->scsi_done(lrbp->cmd);
-                       lrbp->cmd = NULL;
+                       if (lrbp->cmd) {
+                               scsi_dma_unmap(lrbp->cmd);
+                               lrbp->cmd->result = DID_RESET << 16;
+                               lrbp->cmd->scsi_done(lrbp->cmd);
+                               lrbp->cmd = NULL;
+                       }
                }
        }
 
+       /* complete internal command */
+       if (hba->i_cmd.dev_cmd_complete)
+               complete(hba->i_cmd.dev_cmd_complete);
+
        /* clear outstanding request/task bit maps */
        hba->outstanding_reqs = 0;
        hba->outstanding_tasks = 0;

@@ -1068,7 +1330,7 @@ static int ufshcd_slave_alloc(struct scsi_device *sdev)
         * SAM_STAT_TASK_SET_FULL, the LUN queue depth will be adjusted
         * with scsi_adjust_queue_depth.
         */
-       scsi_activate_tcq(sdev, hba->nutrs);
+       scsi_activate_tcq(sdev, SCSI_CMD_QUEUE_SIZE);
        return 0;
 }
 

@@ -1081,7 +1343,7 @@ static void ufshcd_slave_destroy(struct scsi_device *sdev)
        struct ufs_hba *hba;
 
        hba = shost_priv(sdev->host);
-       scsi_deactivate_tcq(sdev, hba->nutrs);
+       scsi_deactivate_tcq(sdev, SCSI_CMD_QUEUE_SIZE);
 }
 
 /**

@@ -1144,7 +1406,7 @@ static void ufshcd_adjust_lun_qdepth(struct scsi_cmnd *cmd)
         * LUN queue depth can be obtained by counting outstanding commands
         * on the LUN.
         */
-       for (i = 0; i < hba->nutrs; i++) {
+       for (i = 0; i < SCSI_CMD_QUEUE_SIZE; i++) {
                if (test_bit(i, &hba->outstanding_reqs)) {
 
                        /*

@@ -1230,27 +1492,36 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 
        switch (ocs) {
        case OCS_SUCCESS:
-
                /* check if the returned transfer response is valid */
-               result = ufshcd_is_valid_req_rsp(lrbp->ucd_rsp_ptr);
-               if (result) {
+               result = ufshcd_get_req_rsp(lrbp->ucd_rsp_ptr);
+
+               switch (result) {
+               case UPIU_TRANSACTION_RESPONSE:
+                       /*
+                        * get the response UPIU result to extract
+                        * the SCSI command status
+                        */
+                       result = ufshcd_get_rsp_upiu_result(lrbp->ucd_rsp_ptr);
+
+                       /*
+                        * get the result based on SCSI status response
+                        * to notify the SCSI midlayer of the command status
+                        */
+                       scsi_status = result & MASK_SCSI_STATUS;
+                       result = ufshcd_scsi_cmd_status(lrbp, scsi_status);
+                       break;
+               case UPIU_TRANSACTION_REJECT_UPIU:
+                       /* TODO: handle Reject UPIU Response */
+                       result = DID_ERROR << 16;
                        dev_err(hba->dev,
-                               "Invalid response = %x\n", result);
+                               "Reject UPIU not fully implemented\n");
                        break;
+               default:
+                       result = DID_ERROR << 16;
+                       dev_err(hba->dev,
+                               "Unexpected request response code = %x\n",
+                               result);
                }
-
-               /*
-                * get the response UPIU result to extract
-                * the SCSI command status
-                */
-               result = ufshcd_get_rsp_upiu_result(lrbp->ucd_rsp_ptr);
-
-               /*
-                * get the result based on SCSI status response
-                * to notify the SCSI midlayer of the command status
-                */
-               scsi_status = result & MASK_SCSI_STATUS;
-               result = ufshcd_scsi_cmd_status(lrbp, scsi_status);
                break;
        case OCS_ABORTED:
                result |= DID_ABORT << 16;

@@ -1290,29 +1561,37 @@ static void ufshcd_uic_cmd_compl(struct ufs_hba *hba)
  */
 static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
 {
-       struct ufshcd_lrb *lrb;
+       struct ufshcd_lrb *lrbp;
+       struct scsi_cmnd *cmd;
        unsigned long completed_reqs;
        u32 tr_doorbell;
        int result;
        int index;
+       bool int_aggr_reset = false;
 
-       lrb = hba->lrb;
        tr_doorbell = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
        completed_reqs = tr_doorbell ^ hba->outstanding_reqs;
 
        for (index = 0; index < hba->nutrs; index++) {
                if (test_bit(index, &completed_reqs)) {
+                       lrbp = &hba->lrb[index];
+                       cmd = lrbp->cmd;
 
-                       result = ufshcd_transfer_rsp_status(hba, &lrb[index]);
-
-                       if (lrb[index].cmd) {
-                               scsi_dma_unmap(lrb[index].cmd);
-                               lrb[index].cmd->result = result;
-                               lrb[index].cmd->scsi_done(lrb[index].cmd);
+                       if (cmd) {
+                               result = ufshcd_transfer_rsp_status(hba, lrbp);
+                               scsi_dma_unmap(cmd);
+                               cmd->result = result;
+                               cmd->scsi_done(cmd);
 
                                /* Mark completed command as NULL in LRB */
-                               lrb[index].cmd = NULL;
+                               lrbp->cmd = NULL;
+                       } else if (lrbp->command_type ==
+                                       UTP_CMD_TYPE_DEV_MANAGE) {
+                               if (hba->i_cmd.dev_cmd_complete)
+                                       complete(hba->i_cmd.dev_cmd_complete);
                        }
+                       /* Don't reset counters for interrupt cmd */
+                       int_aggr_reset |= !lrbp->intr_cmd;
                } /* end of if */
        } /* end of for */
 

@@ -1320,7 +1599,8 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
        hba->outstanding_reqs ^= completed_reqs;
 
        /* Reset interrupt aggregation counters */
-       ufshcd_config_int_aggr(hba, INT_AGGR_RESET);
+       if (int_aggr_reset)
+               ufshcd_config_int_aggr(hba, INT_AGGR_RESET);
 }
 
 /**

@@ -1463,10 +1743,10 @@ ufshcd_issue_tm_cmd(struct ufs_hba *hba,
        task_req_upiup =
                (struct utp_upiu_task_req *) task_req_descp->task_req_upiu;
        task_req_upiup->header.dword_0 =
-               cpu_to_be32(UPIU_HEADER_DWORD(UPIU_TRANSACTION_TASK_REQ, 0,
-                                             lrbp->lun, lrbp->task_tag));
+               UPIU_HEADER_DWORD(UPIU_TRANSACTION_TASK_REQ, 0,
+                                             lrbp->lun, lrbp->task_tag);
        task_req_upiup->header.dword_1 =
-       cpu_to_be32(UPIU_HEADER_DWORD(0, tm_function, 0, 0));
+               UPIU_HEADER_DWORD(0, tm_function, 0, 0);
 
        task_req_upiup->input_param1 = lrbp->lun;
        task_req_upiup->input_param1 =

@@ -1521,7 +1801,7 @@ static int ufshcd_device_reset(struct scsi_cmnd *cmd)
        if (err == FAILED)
                goto out;
 
-       for (pos = 0; pos < hba->nutrs; pos++) {
+       for (pos = 0; pos < SCSI_CMD_QUEUE_SIZE; pos++) {
                if (test_bit(pos, &hba->outstanding_reqs) &&
                    (hba->lrb[tag].lun == hba->lrb[pos].lun)) {
 

@@ -1539,6 +1819,11 @@ static int ufshcd_device_reset(struct scsi_cmnd *cmd)
                        }
                }
        } /* end of for */
+
+       /* complete internal command */
+       if (hba->i_cmd.dev_cmd_complete)
+               complete(hba->i_cmd.dev_cmd_complete);
+
 out:
        return err;
 }

@@ -1618,8 +1903,16 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
        int ret;
 
        ret = ufshcd_link_startup(hba);
-       if (!ret)
-               scsi_scan_host(hba->host);
+       if (ret)
+               goto out;
+
+       ret = ufshcd_validate_dev_connection(hba);
+       if (ret)
+               goto out;
+
+       scsi_scan_host(hba->host);
+out:
+       return;
 }
 
 static struct scsi_host_template ufshcd_driver_template = {

drivers/scsi/ufs/ufshcd.c +1 -0

+       host->cmd_per_lun = SCSI_CMD_QUEUE_SIZE;
 
        host->max_id = UFSHCD_MAX_ID;
        host->max_lun = UFSHCD_MAX_LUNS;

        host->max_channel = UFSHCD_MAX_CHANNEL;

drivers/scsi/ufs/ufshcd.c +3 -0

@@ -1788,6 +2081,9 @@ int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle,
        /* Initialize UIC command mutex */
        mutex_init(&hba->uic_cmd_mutex);
 
+       /* Initialize mutex for internal commands */
+       mutex_init(&hba->i_cmd.dev_cmd_lock);
+
        /* IRQ registration */
        err = request_irq(irq, ufshcd_intr, IRQF_SHARED, UFSHCD, hba);
        if (err) {

drivers/scsi/ufs/ufshcd.h +23 -3

index 49590ee..e41fa5e 100644
@@ -68,6 +68,10 @@
 #define UFSHCD "ufshcd"
 #define UFSHCD_DRIVER_VERSION "0.2"
 
+enum internal_cmd_type {
+       DEV_CMD_TYPE_NOP                = 0x0,
+};
+
 /**
  * struct uic_command - UIC command structure
  * @command: UIC command

@@ -91,7 +95,7 @@ struct uic_command {
 /**
  * struct ufshcd_lrb - local reference block
  * @utr_descriptor_ptr: UTRD address of the command
- * @ucd_cmd_ptr: UCD address of the command
+ * @ucd_req_ptr: UCD address of the command
  * @ucd_rsp_ptr: Response UPIU address for this command
  * @ucd_prdt_ptr: PRDT address of the command
  * @cmd: pointer to SCSI command

@@ -101,10 +105,11 @@ struct uic_command {
  * @command_type: SCSI, UFS, Query.
  * @task_tag: Task tag of the command
  * @lun: LUN of the command
+ * @intr_cmd: Interrupt command (doesn't participate in interrupt aggregation)
  */
 struct ufshcd_lrb {
        struct utp_transfer_req_desc *utr_descriptor_ptr;
-       struct utp_upiu_cmd *ucd_cmd_ptr;
+       struct utp_upiu_req *ucd_req_ptr;
        struct utp_upiu_rsp *ucd_rsp_ptr;
        struct ufshcd_sg_entry *ucd_prdt_ptr;
 

@@ -116,8 +121,20 @@ struct ufshcd_lrb {
        int command_type;
        int task_tag;
        unsigned int lun;
+       bool intr_cmd;
 };
 
+/**
+ * struct ufs_internal_cmd - all assosiated fields with internal commands
+ * @dev_cmd_type: device management command type - Query, NOP OUT
+ * @dev_cmd_lock: lock to allow one internal command at a time
+ * @dev_cmd_complete: internal commands completion
+ */
+struct ufs_internal_cmd {
+       enum internal_cmd_type dev_cmd_type;
+       struct mutex dev_cmd_lock;
+       struct completion *dev_cmd_complete;
+};
 
 /**
  * struct ufs_hba - per adapter private structure

@@ -146,6 +163,7 @@ struct ufshcd_lrb {
  * @intr_mask: Interrupt Mask Bits
  * @feh_workq: Work queue for fatal controller error handling
  * @errors: HBA errors
+ * @i_cmd: ufs internal command information
  */
 struct ufs_hba {
        void __iomem *mmio_base;

@@ -188,6 +206,9 @@ struct ufs_hba {
 
        /* HBA Errors */
        u32 errors;
+
+       /* Internal Request data */
+       struct ufs_internal_cmd i_cmd;
 };
 
 #define ufshcd_writel(hba, val, reg)   \
--

1.7.6
--

Quoted 19 lines

drivers/scsi/ufs/ufshcd.c +19 -0

+/*
+ * ufshcd_wait_for_register - wait for register value to change
+ * @hba - per-adapter interface
+ * @reg - mmio register offset
+ * @mask - mask to apply to read register value
+ * @val - wait condition
+ * @interval_us - polling interval in microsecs
+ * @timeout_ms - timeout in millisecs
+ *
+ * Returns final register value after iteration
+ */
+static u32 ufshcd_wait_for_register(struct ufs_hba *hba, u32 reg, u32 mask,
+               u32 val, unsigned long interval_us, unsigned long timeout_ms)
+{
+       u32 tmp;
+       ktime_t start;
+       unsigned long diff;
+
+       tmp = ufshcd_readl(hba, reg);

drivers/scsi/ufs/ufshcd.c enum { · line 104

Quoted 3 lines

drivers/scsi/ufs/ufshcd.c +3 -0

+
+       start = ktime_get();
+       while ((tmp & mask) == val) {

...as now I notice it, 'val' is the wait condition and the loop continues if the wait condition is met. I feel it's a bit confusing. Wouldn't something like (x != wait_condition) be appropriate?

drivers/scsi/ufs/ufshcd.c enum { · line 110

Quoted 7 lines

drivers/scsi/ufs/ufshcd.c +6 -0

+               /* wakeup within 50us of expiry */
+               usleep_range(interval_us, interval_us + 50);
+               tmp = ufshcd_readl(hba, reg);
+               diff = ktime_to_ms(ktime_sub(ktime_get(), start));
+               if (diff > timeout_ms) {
+                       tmp = ufshcd_readl(hba, reg);

Why this extra read? The register value might have changed during the execution of 2 previous statements, is that the assumption?

Quoted 652 lines

drivers/scsi/ufs/ufshcd.c +364 -108

+                       break;
+               }
+       }
+
+       return tmp;
+}
+
  /**
   * ufshcd_get_intr_mask - Get the interrupt bit mask
   * @hba - Pointer to adapter instance

@@ -223,18 +267,13 @@ static inline void ufshcd_free_hba_memory(struct ufs_hba *hba)
  }
 
  /**
- * ufshcd_is_valid_req_rsp - checks if controller TR response is valid
+ * ufshcd_get_req_rsp - returns the TR response
   * @ucd_rsp_ptr: pointer to response UPIU
- *
- * This function checks the response UPIU for valid transaction type in
- * response field
- * Returns 0 on success, non-zero on failure
   */
  static inline int
-ufshcd_is_valid_req_rsp(struct utp_upiu_rsp *ucd_rsp_ptr)
+ufshcd_get_req_rsp(struct utp_upiu_rsp *ucd_rsp_ptr)
  {
-       return ((be32_to_cpu(ucd_rsp_ptr->header.dword_0) >> 24) ==
-                UPIU_TRANSACTION_RESPONSE) ? 0 : DID_ERROR << 16;
+       return be32_to_cpu(ucd_rsp_ptr->header.dword_0) >> 24;
  }
 
  /**

@@ -331,9 +370,9 @@ static inline void ufshcd_copy_sense_data(struct ufshcd_lrb *lrbp)
  {
         int len;
         if (lrbp->sense_buffer) {
-               len = be16_to_cpu(lrbp->ucd_rsp_ptr->sense_data_len);
+               len = be16_to_cpu(lrbp->ucd_rsp_ptr->sc.sense_data_len);
                 memcpy(lrbp->sense_buffer,
-                       lrbp->ucd_rsp_ptr->sense_data,
+                       lrbp->ucd_rsp_ptr->sc.sense_data,
                         min_t(int, len, SCSI_SENSE_BUFFERSIZE));
         }
  }

@@ -551,76 +590,128 @@ static void ufshcd_disable_intr(struct ufs_hba *hba, u32 intrs)
  }
 
  /**
+ * ufshcd_prepare_req_desc() - Fills the requests header
+ * descriptor according to request
+ * @lrbp: pointer to local reference block
+ * @upiu_flags: flags required in the header
+ * @cmd_dir: requests data direction
+ */
+static void ufshcd_prepare_req_desc(struct ufshcd_lrb *lrbp, u32 *upiu_flags,
+               enum dma_data_direction cmd_dir)
+{
+       struct utp_transfer_req_desc *req_desc = lrbp->utr_descriptor_ptr;
+       u32 data_direction;
+       u32 dword_0;
+
+       if (cmd_dir == DMA_FROM_DEVICE) {
+               data_direction = UTP_DEVICE_TO_HOST;
+               *upiu_flags = UPIU_CMD_FLAGS_READ;
+       } else if (cmd_dir == DMA_TO_DEVICE) {
+               data_direction = UTP_HOST_TO_DEVICE;
+               *upiu_flags = UPIU_CMD_FLAGS_WRITE;
+       } else {
+               data_direction = UTP_NO_DATA_TRANSFER;
+               *upiu_flags = UPIU_CMD_FLAGS_NONE;
+       }
+
+       dword_0 = data_direction | (lrbp->command_type
+                               << UPIU_COMMAND_TYPE_OFFSET);
+       if (lrbp->intr_cmd)
+               dword_0 |= UTP_REQ_DESC_INT_CMD;
+
+       /* Transfer request descriptor header fields */
+       req_desc->header.dword_0 = cpu_to_le32(dword_0);
+
+       /*
+        * assigning invalid value for command status. Controller
+        * updates OCS on command completion, with the command
+        * status
+        */
+       req_desc->header.dword_2 =
+               cpu_to_le32(OCS_INVALID_COMMAND_STATUS);
+}
+
+/**
+ * ufshcd_prepare_utp_scsi_cmd_upiu() - fills the utp_transfer_req_desc,
+ * for scsi commands
+ * @lrbp - local reference block pointer
+ * @upiu_flags - flags
+ */
+static
+void ufshcd_prepare_utp_scsi_cmd_upiu(struct ufshcd_lrb *lrbp, u32 upiu_flags)
+{
+       struct utp_upiu_req *ucd_req_ptr = lrbp->ucd_req_ptr;
+
+       /* command descriptor fields */
+       ucd_req_ptr->header.dword_0 = UPIU_HEADER_DWORD(
+                               UPIU_TRANSACTION_COMMAND, upiu_flags,
+                               lrbp->lun, lrbp->task_tag);
+       ucd_req_ptr->header.dword_1 = UPIU_HEADER_DWORD(
+                               UPIU_COMMAND_SET_TYPE_SCSI, 0, 0, 0);
+
+       /* Total EHS length and Data segment length will be zero */
+       ucd_req_ptr->header.dword_2 = 0;
+
+       ucd_req_ptr->sc.exp_data_transfer_len =
+               cpu_to_be32(lrbp->cmd->sdb.length);
+
+       memcpy(ucd_req_ptr->sc.cdb, lrbp->cmd->cmnd,
+               (min_t(unsigned short, lrbp->cmd->cmd_len, MAX_CDB_SIZE)));
+}
+
+static inline void ufshcd_prepare_utp_nop_upiu(struct ufshcd_lrb *lrbp)
+{
+       struct utp_upiu_req *ucd_req_ptr = lrbp->ucd_req_ptr;
+
+       memset(ucd_req_ptr, 0, sizeof(struct utp_upiu_req));
+
+       /* command descriptor fields */
+       ucd_req_ptr->header.dword_0 =
+               UPIU_HEADER_DWORD(
+                       UPIU_TRANSACTION_NOP_OUT, 0, 0, lrbp->task_tag);
+}
+
+/**
   * ufshcd_compose_upiu - form UFS Protocol Information Unit(UPIU)
+ * @hba - per adapter instance
   * @lrb - pointer to local reference block
   */
-static void ufshcd_compose_upiu(struct ufshcd_lrb *lrbp)
+static int ufshcd_compose_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
  {
-       struct utp_transfer_req_desc *req_desc;
-       struct utp_upiu_cmd *ucd_cmd_ptr;
-       u32 data_direction;
         u32 upiu_flags;
-
-       ucd_cmd_ptr = lrbp->ucd_cmd_ptr;
-       req_desc = lrbp->utr_descriptor_ptr;
+       int ret = 0;
 
         switch (lrbp->command_type) {
         case UTP_CMD_TYPE_SCSI:
-               if (lrbp->cmd->sc_data_direction == DMA_FROM_DEVICE) {
-                       data_direction = UTP_DEVICE_TO_HOST;
-                       upiu_flags = UPIU_CMD_FLAGS_READ;
-               } else if (lrbp->cmd->sc_data_direction == DMA_TO_DEVICE) {
-                       data_direction = UTP_HOST_TO_DEVICE;
-                       upiu_flags = UPIU_CMD_FLAGS_WRITE;
+               if (likely(lrbp->cmd)) {
+                       ufshcd_prepare_req_desc(lrbp, &upiu_flags,
+                                       lrbp->cmd->sc_data_direction);
+                       ufshcd_prepare_utp_scsi_cmd_upiu(lrbp, upiu_flags);
                 } else {
-                       data_direction = UTP_NO_DATA_TRANSFER;
-                       upiu_flags = UPIU_CMD_FLAGS_NONE;
+                       ret = -EINVAL;
                 }
-
-               /* Transfer request descriptor header fields */
-               req_desc->header.dword_0 =
-                       cpu_to_le32(data_direction | UTP_SCSI_COMMAND);
-
-               /*
-                * assigning invalid value for command status. Controller
-                * updates OCS on command completion, with the command
-                * status
-                */
-               req_desc->header.dword_2 =
-                       cpu_to_le32(OCS_INVALID_COMMAND_STATUS);
-
-               /* command descriptor fields */
-               ucd_cmd_ptr->header.dword_0 =
-                       cpu_to_be32(UPIU_HEADER_DWORD(UPIU_TRANSACTION_COMMAND,
-                                                     upiu_flags,
-                                                     lrbp->lun,
-                                                     lrbp->task_tag));
-               ucd_cmd_ptr->header.dword_1 =
-                       cpu_to_be32(
-                               UPIU_HEADER_DWORD(UPIU_COMMAND_SET_TYPE_SCSI,
-                                                 0,
-                                                 0,
-                                                 0));
-
-               /* Total EHS length and Data segment length will be zero */
-               ucd_cmd_ptr->header.dword_2 = 0;
-
-               ucd_cmd_ptr->exp_data_transfer_len =
-                       cpu_to_be32(lrbp->cmd->sdb.length);
-
-               memcpy(ucd_cmd_ptr->cdb,
-                      lrbp->cmd->cmnd,
-                      (min_t(unsigned short,
-                             lrbp->cmd->cmd_len,
-                             MAX_CDB_SIZE)));
                 break;
         case UTP_CMD_TYPE_DEV_MANAGE:
-               /* For query function implementation */
+               ufshcd_prepare_req_desc(lrbp, &upiu_flags, DMA_NONE);
+               if (hba->i_cmd.dev_cmd_type == DEV_CMD_TYPE_NOP)
+                       ufshcd_prepare_utp_nop_upiu(lrbp);
+               else
+                       ret = -EINVAL;
                 break;
         case UTP_CMD_TYPE_UFS:
                 /* For UFS native command implementation */
+               dev_err(hba->dev, "%s: UFS native command are not supported\n",
+                       __func__);
+               ret = -ENOTSUPP;
+               break;
+       default:
+               ret = -ENOTSUPP;
+               dev_err(hba->dev, "%s: unknown command type: 0x%x\n",
+                               __func__, lrbp->command_type);
                 break;
         } /* end of switch */
+
+       return ret;
  }
 
  /**

@@ -654,11 +745,11 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
         lrbp->sense_buffer = cmd->sense_buffer;
         lrbp->task_tag = tag;
         lrbp->lun = cmd->device->lun;
-
+       lrbp->intr_cmd = false;
         lrbp->command_type = UTP_CMD_TYPE_SCSI;
 
         /* form UPIU before issuing the command */
-       ufshcd_compose_upiu(lrbp);
+       ufshcd_compose_upiu(hba, lrbp);
         err = ufshcd_map_sg(lrbp);
         if (err)
                 goto out;

@@ -671,6 +762,139 @@ out:
         return err;
  }
 
+static int ufshcd_compose_internal_cmd(struct ufs_hba *hba,
+               struct ufshcd_lrb *lrbp, enum internal_cmd_type cmd_type)
+{
+       lrbp->cmd = NULL;
+       lrbp->sense_bufflen = 0;
+       lrbp->sense_buffer = NULL;
+       lrbp->task_tag = INTERNAL_CMD_TAG;
+       lrbp->lun = 0; /* internal cmd is not specific to any LUN */
+       lrbp->command_type = UTP_CMD_TYPE_DEV_MANAGE;
+       lrbp->intr_cmd = true; /* No interrupt aggregation */
+       hba->i_cmd.dev_cmd_type = cmd_type;
+
+       return ufshcd_compose_upiu(hba, lrbp);
+}
+
+static int ufshcd_wait_for_internal_cmd(struct ufs_hba *hba,
+               struct ufshcd_lrb *lrbp, int max_timeout)
+{
+       int err = 0;
+       unsigned long timeout;
+       unsigned long flags;
+
+       timeout = wait_for_completion_timeout(hba->i_cmd.dev_cmd_complete,
+                       msecs_to_jiffies(max_timeout));
+
+       spin_lock_irqsave(hba->host->host_lock, flags);
+       hba->i_cmd.dev_cmd_complete = NULL;
+       if (timeout)
+               err = ufshcd_get_tr_ocs(lrbp);
+       else
+               err = -ETIMEDOUT;
+       spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+       return err;
+}
+
+static int
+ufshcd_clear_cmd(struct ufs_hba *hba, int tag)
+{
+       int err = 0;
+       unsigned long flags;
+       u32 reg;
+       u32 mask = 1 << tag;
+
+       /* clear outstanding transaction before retry */
+       spin_lock_irqsave(hba->host->host_lock, flags);
+       ufshcd_utrl_clear(hba, INTERNAL_CMD_TAG);
+       spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+       /* poll for max. 1 sec to clear door bell register by h/w */
+       reg = ufshcd_wait_for_register(hba,
+                       REG_UTP_TRANSFER_REQ_DOOR_BELL,
+                       mask, mask, 1000, 1000);
+       if ((reg & mask) == mask)
+               err = -ETIMEDOUT;
+
+       return err;
+}
+
+/**
+ * ufshcd_internal_cmd_completion() - handles internal command responses
+ * @hba: per adapter instance
+ * @lrbp: pointer to local reference block
+ */
+static int
+ufshcd_internal_cmd_completion(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+       int resp;
+       int err = 0;
+
+       resp = ufshcd_get_req_rsp(lrbp->ucd_rsp_ptr);
+
+       switch (resp) {
+       case UPIU_TRANSACTION_NOP_IN:
+               break;
+       case UPIU_TRANSACTION_REJECT_UPIU:
+               /* TODO: handle Reject UPIU Response */
+               dev_err(hba->dev, "Reject UPIU not fully implemented\n");
+               err = -EPERM;
+               break;
+       default:
+               dev_err(hba->dev, "Invalid internal cmd response: %x\n", resp);
+               err = -EINVAL;
+               break;
+       }
+
+       return err;
+}
+
+/**
+ * ufshcd_exec_internal_cmd() - API for sending internal
+ * requests
+ * @hba - UFS hba
+ * @cmd_type - specifies the type (NOP, Query...)
+ * @timeout - time in seconds
+ *
+ * NOTE: There is only one available tag for internal commands. Thus
+ * synchronisation is the responsibilty of the user.
+ */
+static int ufshcd_exec_internal_cmd(struct ufs_hba *hba,
+               enum internal_cmd_type cmd_type, int timeout)
+{
+       struct ufshcd_lrb *lrbp;
+       int err;
+       struct completion wait;
+       unsigned long flags;
+
+       init_completion(&wait);
+       lrbp = &hba->lrb[INTERNAL_CMD_TAG];
+
+       err = ufshcd_compose_internal_cmd(hba, lrbp, cmd_type);
+       if (unlikely(err))
+               goto out;
+
+       hba->i_cmd.dev_cmd_complete = &wait;
+
+       spin_lock_irqsave(hba->host->host_lock, flags);
+       ufshcd_send_command(hba, INTERNAL_CMD_TAG);
+       spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+       err = ufshcd_wait_for_internal_cmd(hba, lrbp, timeout);
+
+       if (err == -ETIMEDOUT) {
+               if (!ufshcd_clear_cmd(hba, INTERNAL_CMD_TAG))
+                       err = -EAGAIN;
+       } else if (!err) {
+               err = ufshcd_internal_cmd_completion(hba, lrbp);
+       }
+
+out:
+       return err;
+}
+
  /**
   * ufshcd_memory_alloc - allocate memory for host memory space data structures
   * @hba: per adapter instance

@@ -805,8 +1029,8 @@ static void ufshcd_host_memory_configure(struct ufs_hba *hba)
                                 cpu_to_le16(ALIGNED_UPIU_SIZE);
 
                 hba->lrb[i].utr_descriptor_ptr = (utrdlp + i);
-               hba->lrb[i].ucd_cmd_ptr =
-                       (struct utp_upiu_cmd *)(cmd_descp + i);
+               hba->lrb[i].ucd_req_ptr =
+                       (struct utp_upiu_req *)(cmd_descp + i);
                 hba->lrb[i].ucd_rsp_ptr =
                         (struct utp_upiu_rsp *)cmd_descp[i].response_upiu;
                 hba->lrb[i].ucd_prdt_ptr =

@@ -992,6 +1216,38 @@ out:
  }
 
  /**
+ * ufshcd_validate_dev_connection() - Check device connection status
+ * @hba: per-adapter instance
+ *
+ * Send NOP OUT UPIU and wait for NOP IN response to check whether the
+ * device Transport Protocol (UTP) layer is ready after a reset.
+ * If the UTP layer at the device side is not initialized, it may
+ * not respond with NOP IN UPIU within timeout of %NOP_OUT_TIMEOUT
+ * and we retry sending NOP OUT for %NOP_OUT_RETRIES iterations.
+ */
+static int ufshcd_validate_dev_connection(struct ufs_hba *hba)
+{
+       int err = 0;
+       int retries;
+
+       for (retries = NOP_OUT_RETRIES; retries > 0; retries--) {
+               mutex_lock(&hba->i_cmd.dev_cmd_lock);
+               err = ufshcd_exec_internal_cmd(hba, DEV_CMD_TYPE_NOP,
+                                              NOP_OUT_TIMEOUT);
+               mutex_unlock(&hba->i_cmd.dev_cmd_lock);
+
+               if (!err || err == -ETIMEDOUT)
+                       break;
+
+               dev_dbg(hba->dev, "%s: error %d retrying\n", __func__, err);
+       }
+
+       if (err)
+               dev_err(hba->dev, "%s: NOP OUT failed %d\n", __func__, err);
+       return err;
+}
+
+/**
   * ufshcd_do_reset - reset the host controller
   * @hba: per adapter instance
   *

@@ -1014,16 +1270,22 @@ static int ufshcd_do_reset(struct ufs_hba *hba)
         spin_unlock_irqrestore(hba->host->host_lock, flags);
 
         /* abort outstanding commands */
-       for (tag = 0; tag < hba->nutrs; tag++) {
+       for (tag = 0; tag < SCSI_CMD_QUEUE_SIZE; tag++) {
                 if (test_bit(tag, &hba->outstanding_reqs)) {
                         lrbp = &hba->lrb[tag];
-                       scsi_dma_unmap(lrbp->cmd);
-                       lrbp->cmd->result = DID_RESET << 16;
-                       lrbp->cmd->scsi_done(lrbp->cmd);
-                       lrbp->cmd = NULL;
+                       if (lrbp->cmd) {
+                               scsi_dma_unmap(lrbp->cmd);
+                               lrbp->cmd->result = DID_RESET << 16;
+                               lrbp->cmd->scsi_done(lrbp->cmd);
+                               lrbp->cmd = NULL;
+                       }
                 }
         }
 
+       /* complete internal command */
+       if (hba->i_cmd.dev_cmd_complete)
+               complete(hba->i_cmd.dev_cmd_complete);
+
         /* clear outstanding request/task bit maps */
         hba->outstanding_reqs = 0;
         hba->outstanding_tasks = 0;

@@ -1068,7 +1330,7 @@ static int ufshcd_slave_alloc(struct scsi_device *sdev)
          * SAM_STAT_TASK_SET_FULL, the LUN queue depth will be adjusted
          * with scsi_adjust_queue_depth.
          */
-       scsi_activate_tcq(sdev, hba->nutrs);
+       scsi_activate_tcq(sdev, SCSI_CMD_QUEUE_SIZE);
         return 0;
  }
 

@@ -1081,7 +1343,7 @@ static void ufshcd_slave_destroy(struct scsi_device *sdev)
         struct ufs_hba *hba;
 
         hba = shost_priv(sdev->host);
-       scsi_deactivate_tcq(sdev, hba->nutrs);
+       scsi_deactivate_tcq(sdev, SCSI_CMD_QUEUE_SIZE);
  }
 
  /**

@@ -1144,7 +1406,7 @@ static void ufshcd_adjust_lun_qdepth(struct scsi_cmnd *cmd)
          * LUN queue depth can be obtained by counting outstanding commands
          * on the LUN.
          */
-       for (i = 0; i < hba->nutrs; i++) {
+       for (i = 0; i < SCSI_CMD_QUEUE_SIZE; i++) {
                 if (test_bit(i, &hba->outstanding_reqs)) {
 
                         /*

@@ -1230,27 +1492,36 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 
         switch (ocs) {
         case OCS_SUCCESS:
-
                 /* check if the returned transfer response is valid */
-               result = ufshcd_is_valid_req_rsp(lrbp->ucd_rsp_ptr);
-               if (result) {
+               result = ufshcd_get_req_rsp(lrbp->ucd_rsp_ptr);
+
+               switch (result) {
+               case UPIU_TRANSACTION_RESPONSE:
+                       /*
+                        * get the response UPIU result to extract
+                        * the SCSI command status
+                        */
+                       result = ufshcd_get_rsp_upiu_result(lrbp->ucd_rsp_ptr);
+
+                       /*
+                        * get the result based on SCSI status response
+                        * to notify the SCSI midlayer of the command status
+                        */
+                       scsi_status = result & MASK_SCSI_STATUS;
+                       result = ufshcd_scsi_cmd_status(lrbp, scsi_status);
+                       break;
+               case UPIU_TRANSACTION_REJECT_UPIU:
+                       /* TODO: handle Reject UPIU Response */
+                       result = DID_ERROR << 16;
                         dev_err(hba->dev,
-                               "Invalid response = %x\n", result);
+                               "Reject UPIU not fully implemented\n");
                         break;
+               default:
+                       result = DID_ERROR << 16;
+                       dev_err(hba->dev,
+                               "Unexpected request response code = %x\n",
+                               result);
                 }
-
-               /*
-                * get the response UPIU result to extract
-                * the SCSI command status
-                */
-               result = ufshcd_get_rsp_upiu_result(lrbp->ucd_rsp_ptr);
-
-               /*
-                * get the result based on SCSI status response
-                * to notify the SCSI midlayer of the command status
-                */
-               scsi_status = result & MASK_SCSI_STATUS;
-               result = ufshcd_scsi_cmd_status(lrbp, scsi_status);
                 break;
         case OCS_ABORTED:
                 result |= DID_ABORT << 16;

@@ -1290,29 +1561,37 @@ static void ufshcd_uic_cmd_compl(struct ufs_hba *hba)
   */
  static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
  {
-       struct ufshcd_lrb *lrb;
+       struct ufshcd_lrb *lrbp;
+       struct scsi_cmnd *cmd;
         unsigned long completed_reqs;
         u32 tr_doorbell;
         int result;
         int index;
+       bool int_aggr_reset = false;
 
-       lrb = hba->lrb;
         tr_doorbell = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
         completed_reqs = tr_doorbell ^ hba->outstanding_reqs;
 
         for (index = 0; index < hba->nutrs; index++) {
                 if (test_bit(index, &completed_reqs)) {
+                       lrbp = &hba->lrb[index];
+                       cmd = lrbp->cmd;
 
-                       result = ufshcd_transfer_rsp_status(hba, &lrb[index]);
-
-                       if (lrb[index].cmd) {
-                               scsi_dma_unmap(lrb[index].cmd);
-                               lrb[index].cmd->result = result;
-                               lrb[index].cmd->scsi_done(lrb[index].cmd);
+                       if (cmd) {
+                               result = ufshcd_transfer_rsp_status(hba, lrbp);
+                               scsi_dma_unmap(cmd);
+                               cmd->result = result;
+                               cmd->scsi_done(cmd);
 
                                 /* Mark completed command as NULL in LRB */
-                               lrb[index].cmd = NULL;
+                               lrbp->cmd = NULL;
+                       } else if (lrbp->command_type ==
+                                       UTP_CMD_TYPE_DEV_MANAGE) {
+                               if (hba->i_cmd.dev_cmd_complete)
+                                       complete(hba->i_cmd.dev_cmd_complete);
                         }
+                       /* Don't reset counters for interrupt cmd */
+                       int_aggr_reset |= !lrbp->intr_cmd;
                 } /* end of if */
         } /* end of for */
 

@@ -1320,7 +1599,8 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
         hba->outstanding_reqs ^= completed_reqs;
 
         /* Reset interrupt aggregation counters */
-       ufshcd_config_int_aggr(hba, INT_AGGR_RESET);
+       if (int_aggr_reset)
+               ufshcd_config_int_aggr(hba, INT_AGGR_RESET);
  }
 
  /**

@@ -1463,10 +1743,10 @@ ufshcd_issue_tm_cmd(struct ufs_hba *hba,
         task_req_upiup =
                 (struct utp_upiu_task_req *) task_req_descp->task_req_upiu;
         task_req_upiup->header.dword_0 =
-               cpu_to_be32(UPIU_HEADER_DWORD(UPIU_TRANSACTION_TASK_REQ, 0,
-                                             lrbp->lun, lrbp->task_tag));
+               UPIU_HEADER_DWORD(UPIU_TRANSACTION_TASK_REQ, 0,
+                                             lrbp->lun, lrbp->task_tag);
         task_req_upiup->header.dword_1 =
-       cpu_to_be32(UPIU_HEADER_DWORD(0, tm_function, 0, 0));
+               UPIU_HEADER_DWORD(0, tm_function, 0, 0);
 
         task_req_upiup->input_param1 = lrbp->lun;
         task_req_upiup->input_param1 =

@@ -1521,7 +1801,7 @@ static int ufshcd_device_reset(struct scsi_cmnd *cmd)
         if (err == FAILED)
                 goto out;
 
-       for (pos = 0; pos < hba->nutrs; pos++) {
+       for (pos = 0; pos < SCSI_CMD_QUEUE_SIZE; pos++) {
                 if (test_bit(pos, &hba->outstanding_reqs) &&
                     (hba->lrb[tag].lun == hba->lrb[pos].lun)) {
 

@@ -1539,6 +1819,11 @@ static int ufshcd_device_reset(struct scsi_cmnd *cmd)
                         }
                 }
         } /* end of for */
+
+       /* complete internal command */
+       if (hba->i_cmd.dev_cmd_complete)
+               complete(hba->i_cmd.dev_cmd_complete);
+
  out:
         return err;
  }

@@ -1618,8 +1903,16 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
         int ret;
 
         ret = ufshcd_link_startup(hba);
-       if (!ret)
-               scsi_scan_host(hba->host);
+       if (ret)
+               goto out;
+
+       ret = ufshcd_validate_dev_connection(hba);
+       if (ret)
+               goto out;
+
+       scsi_scan_host(hba->host);
+out:
+       return;
  }
 
  static struct scsi_host_template ufshcd_driver_template = {

drivers/scsi/ufs/ufshcd.c int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle, · line 2067

Quoted 6 lines

drivers/scsi/ufs/ufshcd.c +1 -2

@@ -1771,8 +2064,8 @@ int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle,
         /* Configure LRB */
         ufshcd_host_memory_configure(hba);
 
-       host->can_queue = hba->nutrs;
-       host->cmd_per_lun = hba->nutrs;
+       host->can_queue = SCSI_CMD_QUEUE_SIZE;

I don't think this is appropriate. Reserving a slot exclusively for query/DM requests is not optimal. can_queue should be changed dynamically, scsi_adjust_queue_depth() maybe?

Quoted 92 lines

drivers/scsi/ufs/ufshcd.c +1 -0

+       host->cmd_per_lun = SCSI_CMD_QUEUE_SIZE;
 
         host->max_id = UFSHCD_MAX_ID;
         host->max_lun = UFSHCD_MAX_LUNS;

         host->max_channel = UFSHCD_MAX_CHANNEL;

drivers/scsi/ufs/ufshcd.c +3 -0

@@ -1788,6 +2081,9 @@ int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle,
         /* Initialize UIC command mutex */
         mutex_init(&hba->uic_cmd_mutex);
 
+       /* Initialize mutex for internal commands */
+       mutex_init(&hba->i_cmd.dev_cmd_lock);
+
         /* IRQ registration */
         err = request_irq(irq, ufshcd_intr, IRQF_SHARED, UFSHCD, hba);
         if (err) {

drivers/scsi/ufs/ufshcd.h +23 -3

index 49590ee..e41fa5e 100644
@@ -68,6 +68,10 @@
  #define UFSHCD "ufshcd"
  #define UFSHCD_DRIVER_VERSION "0.2"
 
+enum internal_cmd_type {
+       DEV_CMD_TYPE_NOP                = 0x0,
+};
+
  /**
   * struct uic_command - UIC command structure
   * @command: UIC command

@@ -91,7 +95,7 @@ struct uic_command {
  /**
   * struct ufshcd_lrb - local reference block
   * @utr_descriptor_ptr: UTRD address of the command
- * @ucd_cmd_ptr: UCD address of the command
+ * @ucd_req_ptr: UCD address of the command
   * @ucd_rsp_ptr: Response UPIU address for this command
   * @ucd_prdt_ptr: PRDT address of the command
   * @cmd: pointer to SCSI command

@@ -101,10 +105,11 @@ struct uic_command {
   * @command_type: SCSI, UFS, Query.
   * @task_tag: Task tag of the command
   * @lun: LUN of the command
+ * @intr_cmd: Interrupt command (doesn't participate in interrupt aggregation)
   */
  struct ufshcd_lrb {
         struct utp_transfer_req_desc *utr_descriptor_ptr;
-       struct utp_upiu_cmd *ucd_cmd_ptr;
+       struct utp_upiu_req *ucd_req_ptr;
         struct utp_upiu_rsp *ucd_rsp_ptr;
         struct ufshcd_sg_entry *ucd_prdt_ptr;
 

@@ -116,8 +121,20 @@ struct ufshcd_lrb {
         int command_type;
         int task_tag;
         unsigned int lun;
+       bool intr_cmd;
  };
 
+/**
+ * struct ufs_internal_cmd - all assosiated fields with internal commands
+ * @dev_cmd_type: device management command type - Query, NOP OUT
+ * @dev_cmd_lock: lock to allow one internal command at a time
+ * @dev_cmd_complete: internal commands completion
+ */
+struct ufs_internal_cmd {
+       enum internal_cmd_type dev_cmd_type;
+       struct mutex dev_cmd_lock;
+       struct completion *dev_cmd_complete;
+};
 
  /**
   * struct ufs_hba - per adapter private structure

@@ -146,6 +163,7 @@ struct ufshcd_lrb {
   * @intr_mask: Interrupt Mask Bits
   * @feh_workq: Work queue for fatal controller error handling
   * @errors: HBA errors
+ * @i_cmd: ufs internal command information
   */
  struct ufs_hba {
         void __iomem *mmio_base;

@@ -188,6 +206,9 @@ struct ufs_hba {
 
         /* HBA Errors */
         u32 errors;
+
+       /* Internal Request data */
+       struct ufs_internal_cmd i_cmd;
  };
 
  #define ufshcd_writel(hba, val, reg)   \
--

Quoted 2 lines

1.7.6
--

--
~Santosh
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html

Quoted 6 lines

  static struct scsi_host_template ufshcd_driver_template = {

drivers/scsi/ufs/ufshcd.c +0 -0

@@ -1771,8 +2064,8 @@ int ufshcd_init(struct device *dev, struct
 ufs_hba **hba_handle,
         /* Configure LRB */
         ufshcd_host_memory_configure(hba);
 

drivers/scsi/ufs/ufshcd.c int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle, · line 2067

Quoted 3 lines

drivers/scsi/ufs/ufshcd.c +1 -2

-       host->can_queue = hba->nutrs;
-       host->cmd_per_lun = hba->nutrs;
+       host->can_queue = SCSI_CMD_QUEUE_SIZE;

I don't think this is appropriate. Reserving a slot exclusively for query/DM requests is not optimal. can_queue should be changed dynamically, scsi_adjust_queue_depth() maybe?

Quoted 7 lines · Sujit Reddy Thumma

Quoted 7 lines

  static struct scsi_host_template ufshcd_driver_template = {

drivers/scsi/ufs/ufshcd.c +0 -0

@@ -1771,8 +2064,8 @@ int ufshcd_init(struct device *dev, struct
 ufs_hba **hba_handle,
         /* Configure LRB */
         ufshcd_host_memory_configure(hba);
 

Quoted 9 lines

drivers/scsi/ufs/ufshcd.c int ufshcd_init(struct device *dev, struct ufs_hba **hba_handle, · line 2067

Quoted 3 lines

drivers/scsi/ufs/ufshcd.c +1 -2

-       host->can_queue = hba->nutrs;
-       host->cmd_per_lun = hba->nutrs;
+       host->can_queue = SCSI_CMD_QUEUE_SIZE;

I don't think this is appropriate. Reserving a slot exclusively for query/DM requests is not optimal. can_queue should be changed dynamically, scsi_adjust_queue_depth() maybe?

The motivation to change the design for this patch is that routing query command through SCSI layer raised problems when we are trying to improve the fatal error handling as we need to block the SCSI layer and recover the link. Hence, the need to have the query/DM command send as internal commands. Which probably makes sense.

One possible option was to look for a free command slot whenever we try to send an internal command, but getting a free slot is not always guaranteed.

Even if we get hold of a tag, there is no way we can explain this to SCSI/block layer that particular tag is in use internally (case where normal query requests are sent in tandem with SCSI requests). In which case, other option is to use tag[31] as you have said on need basis and change the queue depth to 31. This again has problems - one changing queue depth doesn't take effect immediately but for the next command. Second, if the command in tag[31] is the root cause of the fatal error and is stuck, then the internal command has to wait forever (until scsi timesout) to plan recovery. Considering, all these factors it is better to reserve a tag and use it for internal commands instead of playing around with the tags internally without/partially informing SCSI/block layers.

I am open for discussion, if there are any suggestions to handle such LLD requirements in the SCSI layer optimally.

Coming to how optimal is to work with 31 slots instead of h/w defined 32 is something which we can answer when we have true multi queueing. AFAIK, there may not exist real-world applications which utilize full 32 tags at particular instant. SATA AHCI controller driver which is ubiquitous in modern systems also reserves a slot for internal commands which is used only in case of error handling and AFAIK, no one has ever reported performance problems with this (its about 7 years the commit to reserve a slot is merged into Linux tree).

I hope this explains the intent. Please let me know what do you think.

/**

+ *  ufshcd_query_request() - API for issuing query request to the device.
+ *  @hba: ufs driver context
+ *  @query: params for query request
+ *  @descriptor: buffer for sending/receiving descriptor
+ *  @retries: number of times to try executing the command
+ *
+ *   All necessary fields for issuing a query and receiving its response
+ *   are stored in the UFS hba struct. We can use this method since we know
+ *   there is only one active query request or any internal command at all
+ *   times.

+ */

drivers/scsi/ufs/ufshcd.c +12 -0

+static int ufshcd_send_query_request(struct ufs_hba *hba,
+                                       struct ufs_query_req *query,
+                                       u8 *descriptor,
+                                       struct ufs_query_res *response)
+{
+       int ret;
+
+       BUG_ON(!hba);
+       if (!query || !response) {
+               dev_err(hba->dev,
+                       "%s: NULL pointer query = %p, response = %p\n",
+                       __func__, query, response);

drivers/scsi/ufs/ufshcd.c +10 -0

+
+       hba->i_cmd.query.request = NULL;
+       hba->i_cmd.query.response = NULL;
+       hba->i_cmd.query.descriptor = NULL;
+       mutex_unlock(&hba->i_cmd.dev_cmd_lock);
+
+       return ret;
+}
+
+/**

Quoted 29 lines

/**

+ *  ufshcd_query_request() - API for issuing query request to the device.
+ *  @hba: ufs driver context
+ *  @query: params for query request
+ *  @descriptor: buffer for sending/receiving descriptor
+ *  @retries: number of times to try executing the command
+ *
+ *   All necessary fields for issuing a query and receiving its response
+ *   are stored in the UFS hba struct. We can use this method since we know
+ *   there is only one active query request or any internal command at all
+ *   times.

+ */

drivers/scsi/ufs/ufshcd.c +16 -0

+static int ufshcd_send_query_request(struct ufs_hba *hba,
+                                       struct ufs_query_req *query,
+                                       u8 *descriptor,
+                                       struct ufs_query_res *response)
+{
+       int ret;
+
+       BUG_ON(!hba);
+       if (!query || !response) {
+               dev_err(hba->dev,
+                       "%s: NULL pointer query = %p, response = %p\n",
+                       __func__, query, response);
+               return -EINVAL;
+       }
+
+       mutex_lock(&hba->i_cmd.dev_cmd_lock);

drivers/scsi/ufs/ufshcd.c out: · line 1045

Quoted 6 lines

drivers/scsi/ufs/ufshcd.c +6 -0

+       hba->i_cmd.query.request = query;
+       hba->i_cmd.query.response = response;
+       hba->i_cmd.query.descriptor = descriptor;
+
+       ret = ufshcd_exec_internal_cmd(hba, DEV_CMD_TYPE_QUERY,
+                                       QUERY_REQ_TIMEOUT);

Can this be generic, as external query commands might also use it?

Quoted 11 lines

drivers/scsi/ufs/ufshcd.c +10 -0

+
+       hba->i_cmd.query.request = NULL;
+       hba->i_cmd.query.response = NULL;
+       hba->i_cmd.query.descriptor = NULL;
+       mutex_unlock(&hba->i_cmd.dev_cmd_lock);
+
+       return ret;
+}
+
+/**

Quoted 34 lines · Santosh Y

Quoted 34 lines

/**
+ * ufshcd_query_request() - API for issuing query request to the device.

+ *  @hba: ufs driver context
+ *  @query: params for query request
+ *  @descriptor: buffer for sending/receiving descriptor
+ *  @retries: number of times to try executing the command

+ *
+ * All necessary fields for issuing a query and receiving its response
+ * are stored in the UFS hba struct. We can use this method since we
know
+ * there is only one active query request or any internal command at
all
+ * times.
+ */

drivers/scsi/ufs/ufshcd.c +17 -0

+static int ufshcd_send_query_request(struct ufs_hba *hba,
+                                       struct ufs_query_req *query,
+                                       u8 *descriptor,
+                                       struct ufs_query_res *response)
+{
+       int ret;
+
+       BUG_ON(!hba);
+       if (!query || !response) {
+               dev_err(hba->dev,
+                       "%s: NULL pointer query = %p, response = %p\n",
+                       __func__, query, response);
+               return -EINVAL;
+       }
+
+       mutex_lock(&hba->i_cmd.dev_cmd_lock);
+       hba->i_cmd.query.request = query;

Quoted 8 lines

drivers/scsi/ufs/ufshcd.c out: · line 1045

Quoted 5 lines

drivers/scsi/ufs/ufshcd.c +5 -0

+       hba->i_cmd.query.response = response;
+       hba->i_cmd.query.descriptor = descriptor;
+
+       ret = ufshcd_exec_internal_cmd(hba, DEV_CMD_TYPE_QUERY,
+                                       QUERY_REQ_TIMEOUT);

Can this be generic, as external query commands might also use it?

External query commands can call ufshcd_send_query_request() directly, without going into hassle of taking mutex lock and filling internal cmd structure.

Quoted 15 lines

drivers/scsi/ufs/ufshcd.c out: · line 1055

Quoted 12 lines

drivers/scsi/ufs/ufshcd.c +10 -0

+
+       hba->i_cmd.query.request = NULL;
+       hba->i_cmd.query.response = NULL;
+       hba->i_cmd.query.descriptor = NULL;
+       mutex_unlock(&hba->i_cmd.dev_cmd_lock);
+
+       return ret;
+}
+
+/**

--
Regards,
Sujit