[SCSI] ufs: Set fDeviceInit flag to initiate device initialization

Allow UFS device to complete its initialization and accept
SCSI commands by setting fDeviceInit flag. The device may take
time for this operation and hence the host should poll until
fDeviceInit flag is toggled to zero. This step is mandated by
UFS device specification for device initialization completion.

Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Santosh Y <santoshsy@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 235 insertions, 3 deletions

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index ed20156..7b581f7 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -48,6 +48,14 @@
 /* Timeout after 30 msecs if NOP OUT hangs without response */
 #define NOP_OUT_TIMEOUT    30 /* msecs */
 
+/* Query request retries */
+#define QUERY_REQ_RETRIES 10
+/* Query request timeout */
+#define QUERY_REQ_TIMEOUT 30 /* msec */
+
+/* Expose the flag value from utp_upiu_query.value */
+#define MASK_QUERY_UPIU_FLAG_LOC 0xFF
+
 enum {
 	UFSHCD_MAX_CHANNEL	= 0,
 	UFSHCD_MAX_ID		= 1,
@@ -341,6 +349,60 @@ static inline void ufshcd_copy_sense_data(struct ufshcd_lrb *lrbp)
 }
 
 /**
+ * ufshcd_query_to_cpu() - formats the buffer to native cpu endian
+ * @response: upiu query response to convert
+ */
+static inline void ufshcd_query_to_cpu(struct utp_upiu_query *response)
+{
+	response->length = be16_to_cpu(response->length);
+	response->value = be32_to_cpu(response->value);
+}
+
+/**
+ * ufshcd_query_to_be() - formats the buffer to big endian
+ * @request: upiu query request to convert
+ */
+static inline void ufshcd_query_to_be(struct utp_upiu_query *request)
+{
+	request->length = cpu_to_be16(request->length);
+	request->value = cpu_to_be32(request->value);
+}
+
+/**
+ * ufshcd_copy_query_response() - Copy the Query Response and the data
+ * descriptor
+ * @hba: per adapter instance
+ * @lrb - pointer to local reference block
+ */
+static
+void ufshcd_copy_query_response(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+	struct ufs_query_res *query_res = &hba->dev_cmd.query.response;
+
+	/* Get the UPIU response */
+	query_res->response = ufshcd_get_rsp_upiu_result(lrbp->ucd_rsp_ptr) >>
+			UPIU_RSP_CODE_OFFSET;
+
+	memcpy(&query_res->upiu_res, &lrbp->ucd_rsp_ptr->qr, QUERY_OSF_SIZE);
+	ufshcd_query_to_cpu(&query_res->upiu_res);
+
+
+	/* Get the descriptor */
+	if (lrbp->ucd_rsp_ptr->qr.opcode == UPIU_QUERY_OPCODE_READ_DESC) {
+		u8 *descp = (u8 *)&lrbp->ucd_rsp_ptr +
+				GENERAL_UPIU_REQUEST_SIZE;
+		u16 len;
+
+		/* data segment length */
+		len = be32_to_cpu(lrbp->ucd_rsp_ptr->header.dword_2) &
+						MASK_QUERY_DATA_SEG_LEN;
+
+		memcpy(hba->dev_cmd.query.descriptor, descp,
+				min_t(u16, len, QUERY_DESC_MAX_SIZE));
+	}
+}
+
+/**
  * ufshcd_hba_capabilities - Read controller capabilities
  * @hba: per adapter instance
  */
@@ -622,6 +684,45 @@ void ufshcd_prepare_utp_scsi_cmd_upiu(struct ufshcd_lrb *lrbp, u32 upiu_flags)
 		(min_t(unsigned short, lrbp->cmd->cmd_len, MAX_CDB_SIZE)));
 }
 
+/**
+ * ufshcd_prepare_utp_query_req_upiu() - fills the utp_transfer_req_desc,
+ * for query requsts
+ * @hba: UFS hba
+ * @lrbp: local reference block pointer
+ * @upiu_flags: flags
+ */
+static void ufshcd_prepare_utp_query_req_upiu(struct ufs_hba *hba,
+				struct ufshcd_lrb *lrbp, u32 upiu_flags)
+{
+	struct utp_upiu_req *ucd_req_ptr = lrbp->ucd_req_ptr;
+	struct ufs_query *query = &hba->dev_cmd.query;
+	u16 len = query->request.upiu_req.length;
+	u8 *descp = (u8 *)lrbp->ucd_req_ptr + GENERAL_UPIU_REQUEST_SIZE;
+
+	/* Query request header */
+	ucd_req_ptr->header.dword_0 = UPIU_HEADER_DWORD(
+			UPIU_TRANSACTION_QUERY_REQ, upiu_flags,
+			lrbp->lun, lrbp->task_tag);
+	ucd_req_ptr->header.dword_1 = UPIU_HEADER_DWORD(
+			0, query->request.query_func, 0, 0);
+
+	/* Data segment length */
+	ucd_req_ptr->header.dword_2 = UPIU_HEADER_DWORD(
+			0, 0, len >> 8, (u8)len);
+
+	/* Copy the Query Request buffer as is */
+	memcpy(&ucd_req_ptr->qr, &query->request.upiu_req,
+			QUERY_OSF_SIZE);
+	ufshcd_query_to_be(&ucd_req_ptr->qr);
+
+	/* Copy the Descriptor */
+	if ((len > 0) && (query->request.upiu_req.opcode ==
+					UPIU_QUERY_OPCODE_WRITE_DESC)) {
+		memcpy(descp, query->descriptor,
+				min_t(u16, len, QUERY_DESC_MAX_SIZE));
+	}
+}
+
 static inline void ufshcd_prepare_utp_nop_upiu(struct ufshcd_lrb *lrbp)
 {
 	struct utp_upiu_req *ucd_req_ptr = lrbp->ucd_req_ptr;
@@ -656,7 +757,10 @@ static int ufshcd_compose_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 		break;
 	case UTP_CMD_TYPE_DEV_MANAGE:
 		ufshcd_prepare_req_desc_hdr(lrbp, &upiu_flags, DMA_NONE);
-		if (hba->dev_cmd.type == DEV_CMD_TYPE_NOP)
+		if (hba->dev_cmd.type == DEV_CMD_TYPE_QUERY)
+			ufshcd_prepare_utp_query_req_upiu(
+					hba, lrbp, upiu_flags);
+		else if (hba->dev_cmd.type == DEV_CMD_TYPE_NOP)
 			ufshcd_prepare_utp_nop_upiu(lrbp);
 		else
 			ret = -EINVAL;
@@ -800,6 +904,9 @@ ufshcd_dev_cmd_completion(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 					__func__, resp);
 		}
 		break;
+	case UPIU_TRANSACTION_QUERY_RSP:
+		ufshcd_copy_query_response(hba, lrbp);
+		break;
 	case UPIU_TRANSACTION_REJECT_UPIU:
 		/* TODO: handle Reject UPIU Response */
 		err = -EPERM;
@@ -889,8 +996,8 @@ static inline void ufshcd_put_dev_cmd_tag(struct ufs_hba *hba, int tag)
  * @cmd_type - specifies the type (NOP, Query...)
  * @timeout - time in seconds
  *
- * NOTE: There is only one available tag for device management commands. Thus
- * synchronisation is the responsibilty of the user.
+ * NOTE: Since there is only one available tag for device management commands,
+ * it is expected you hold the hba->dev_cmd.lock mutex.
  */
 static int ufshcd_exec_dev_cmd(struct ufs_hba *hba,
 		enum dev_cmd_type cmd_type, int timeout)
@@ -930,6 +1037,76 @@ out_put_tag:
 }
 
 /**
+ * ufshcd_query_flag() - API function for sending flag query requests
+ * hba: per-adapter instance
+ * query_opcode: flag query to perform
+ * idn: flag idn to access
+ * flag_res: the flag value after the query request completes
+ *
+ * Returns 0 for success, non-zero in case of failure
+ */
+static int ufshcd_query_flag(struct ufs_hba *hba, enum query_opcode opcode,
+			enum flag_idn idn, bool *flag_res)
+{
+	struct ufs_query_req *request;
+	struct ufs_query_res *response;
+	int err;
+
+	BUG_ON(!hba);
+
+	mutex_lock(&hba->dev_cmd.lock);
+	request = &hba->dev_cmd.query.request;
+	response = &hba->dev_cmd.query.response;
+	memset(request, 0, sizeof(struct ufs_query_req));
+	memset(response, 0, sizeof(struct ufs_query_res));
+
+	switch (opcode) {
+	case UPIU_QUERY_OPCODE_SET_FLAG:
+	case UPIU_QUERY_OPCODE_CLEAR_FLAG:
+	case UPIU_QUERY_OPCODE_TOGGLE_FLAG:
+		request->query_func = UPIU_QUERY_FUNC_STANDARD_WRITE_REQUEST;
+		break;
+	case UPIU_QUERY_OPCODE_READ_FLAG:
+		request->query_func = UPIU_QUERY_FUNC_STANDARD_READ_REQUEST;
+		if (!flag_res) {
+			/* No dummy reads */
+			dev_err(hba->dev, "%s: Invalid argument for read request\n",
+					__func__);
+			err = -EINVAL;
+			goto out_unlock;
+		}
+		break;
+	default:
+		dev_err(hba->dev,
+			"%s: Expected query flag opcode but got = %d\n",
+			__func__, opcode);
+		err = -EINVAL;
+		goto out_unlock;
+	}
+	request->upiu_req.opcode = opcode;
+	request->upiu_req.idn = idn;
+
+	/* Send query request */
+	err = ufshcd_exec_dev_cmd(hba, DEV_CMD_TYPE_QUERY,
+			QUERY_REQ_TIMEOUT);
+
+	if (err) {
+		dev_err(hba->dev,
+			"%s: Sending flag query for idn %d failed, err = %d\n",
+			__func__, idn, err);
+		goto out_unlock;
+	}
+
+	if (flag_res)
+		*flag_res = (response->upiu_res.value &
+				MASK_QUERY_UPIU_FLAG_LOC) & 0x1;
+
+out_unlock:
+	mutex_unlock(&hba->dev_cmd.lock);
+	return err;
+}
+
+/**
  * ufshcd_memory_alloc - allocate memory for host memory space data structures
  * @hba: per adapter instance
  *
@@ -1099,6 +1276,57 @@ static int ufshcd_dme_link_startup(struct ufs_hba *hba)
 }
 
 /**
+ * ufshcd_complete_dev_init() - checks device readiness
+ * hba: per-adapter instance
+ *
+ * Set fDeviceInit flag and poll until device toggles it.
+ */
+static int ufshcd_complete_dev_init(struct ufs_hba *hba)
+{
+	int i, retries, err = 0;
+	bool flag_res = 1;
+
+	for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
+		/* Set the fDeviceInit flag */
+		err = ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_SET_FLAG,
+					QUERY_FLAG_IDN_FDEVICEINIT, NULL);
+		if (!err || err == -ETIMEDOUT)
+			break;
+		dev_dbg(hba->dev, "%s: error %d retrying\n", __func__, err);
+	}
+	if (err) {
+		dev_err(hba->dev,
+			"%s setting fDeviceInit flag failed with error %d\n",
+			__func__, err);
+		goto out;
+	}
+
+	/* poll for max. 100 iterations for fDeviceInit flag to clear */
+	for (i = 0; i < 100 && !err && flag_res; i++) {
+		for (retries = QUERY_REQ_RETRIES; retries > 0; retries--) {
+			err = ufshcd_query_flag(hba,
+					UPIU_QUERY_OPCODE_READ_FLAG,
+					QUERY_FLAG_IDN_FDEVICEINIT, &flag_res);
+			if (!err || err == -ETIMEDOUT)
+				break;
+			dev_dbg(hba->dev, "%s: error %d retrying\n", __func__,
+					err);
+		}
+	}
+	if (err)
+		dev_err(hba->dev,
+			"%s reading fDeviceInit flag failed with error %d\n",
+			__func__, err);
+	else if (flag_res)
+		dev_err(hba->dev,
+			"%s fDeviceInit was not cleared by the device\n",
+			__func__);
+
+out:
+	return err;
+}
+
+/**
  * ufshcd_make_hba_operational - Make UFS controller operational
  * @hba: per adapter instance
  *
@@ -1953,6 +2181,10 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
 	if (ret)
 		goto out;
 
+	ret = ufshcd_complete_dev_init(hba);
+	if (ret)
+		goto out;
+
 	scsi_scan_host(hba->host);
 out:
 	return;