[SCSI] ufshcd: UFS Host controller driver

This patch adds support for Universal Flash Storage(UFS)
host controllers. The UFS host controller driver
includes host controller initialization method.

The Initialization process involves following steps:
 - Initiate UFS Host Controller initialization process by writing
   to Host controller enable register
 - Configure UFS Host controller registers with host memory space
   datastructure offsets.
 - Unipro link startup procedure
 - Check for connected device
 - Configure UFS host controller to process requests
 - Enable required interrupts
 - Configure interrupt aggregation

[jejb: fix warnings in 32 bit compile]
Signed-off-by: Santosh Yaraganavi <santoshsy@gmail.com>
Signed-off-by: Vinayak Holikatti <vinholikatti@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@linaro.org>
Reviewed-by: Vishak G <vishak.g@samsung.com>
Reviewed-by: Girish K S <girish.shivananjappa@linaro.org>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 1978 insertions, 0 deletions

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
new file mode 100644
index 00000000000..52b96e8bf92
--- /dev/null
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -0,0 +1,1978 @@
+/*
+ * Universal Flash Storage Host controller driver
+ *
+ * This code is based on drivers/scsi/ufs/ufshcd.c
+ * Copyright (C) 2011-2012 Samsung India Software Operations
+ *
+ * Santosh Yaraganavi <santosh.sy@samsung.com>
+ * Vinayak Holikatti <h.vinayak@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * NO WARRANTY
+ * THE PROGRAM IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT
+ * LIMITATION, ANY WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Each Recipient is
+ * solely responsible for determining the appropriateness of using and
+ * distributing the Program and assumes all risks associated with its
+ * exercise of rights under this Agreement, including but not limited to
+ * the risks and costs of program errors, damage to or loss of data,
+ * programs or equipment, and unavailability or interruption of operations.
+
+ * DISCLAIMER OF LIABILITY
+ * NEITHER RECIPIENT NOR ANY CONTRIBUTORS SHALL HAVE ANY LIABILITY FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS), HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+ * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OR DISTRIBUTION OF THE PROGRAM OR THE EXERCISE OF ANY RIGHTS GRANTED
+ * HEREUNDER, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/wait.h>
+#include <linux/bitops.h>
+
+#include <asm/irq.h>
+#include <asm/byteorder.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_eh.h>
+
+#include "ufs.h"
+#include "ufshci.h"
+
+#define UFSHCD "ufshcd"
+#define UFSHCD_DRIVER_VERSION "0.1"
+
+enum {
+	UFSHCD_MAX_CHANNEL	= 0,
+	UFSHCD_MAX_ID		= 1,
+	UFSHCD_MAX_LUNS		= 8,
+	UFSHCD_CMD_PER_LUN	= 32,
+	UFSHCD_CAN_QUEUE	= 32,
+};
+
+/* UFSHCD states */
+enum {
+	UFSHCD_STATE_OPERATIONAL,
+	UFSHCD_STATE_RESET,
+	UFSHCD_STATE_ERROR,
+};
+
+/* Interrupt configuration options */
+enum {
+	UFSHCD_INT_DISABLE,
+	UFSHCD_INT_ENABLE,
+	UFSHCD_INT_CLEAR,
+};
+
+/* Interrupt aggregation options */
+enum {
+	INT_AGGR_RESET,
+	INT_AGGR_CONFIG,
+};
+
+/**
+ * struct uic_command - UIC command structure
+ * @command: UIC command
+ * @argument1: UIC command argument 1
+ * @argument2: UIC command argument 2
+ * @argument3: UIC command argument 3
+ * @cmd_active: Indicate if UIC command is outstanding
+ * @result: UIC command result
+ */
+struct uic_command {
+	u32 command;
+	u32 argument1;
+	u32 argument2;
+	u32 argument3;
+	int cmd_active;
+	int result;
+};
+
+/**
+ * struct ufs_hba - per adapter private structure
+ * @mmio_base: UFSHCI base register address
+ * @ucdl_base_addr: UFS Command Descriptor base address
+ * @utrdl_base_addr: UTP Transfer Request Descriptor base address
+ * @utmrdl_base_addr: UTP Task Management Descriptor base address
+ * @ucdl_dma_addr: UFS Command Descriptor DMA address
+ * @utrdl_dma_addr: UTRDL DMA address
+ * @utmrdl_dma_addr: UTMRDL DMA address
+ * @host: Scsi_Host instance of the driver
+ * @pdev: PCI device handle
+ * @lrb: local reference block
+ * @outstanding_tasks: Bits representing outstanding task requests
+ * @outstanding_reqs: Bits representing outstanding transfer requests
+ * @capabilities: UFS Controller Capabilities
+ * @nutrs: Transfer Request Queue depth supported by controller
+ * @nutmrs: Task Management Queue depth supported by controller
+ * @active_uic_cmd: handle of active UIC command
+ * @ufshcd_tm_wait_queue: wait queue for task management
+ * @tm_condition: condition variable for task management
+ * @ufshcd_state: UFSHCD states
+ * @int_enable_mask: Interrupt Mask Bits
+ * @uic_workq: Work queue for UIC completion handling
+ * @feh_workq: Work queue for fatal controller error handling
+ * @errors: HBA errors
+ */
+struct ufs_hba {
+	void __iomem *mmio_base;
+
+	/* Virtual memory reference */
+	struct utp_transfer_cmd_desc *ucdl_base_addr;
+	struct utp_transfer_req_desc *utrdl_base_addr;
+	struct utp_task_req_desc *utmrdl_base_addr;
+
+	/* DMA memory reference */
+	dma_addr_t ucdl_dma_addr;
+	dma_addr_t utrdl_dma_addr;
+	dma_addr_t utmrdl_dma_addr;
+
+	struct Scsi_Host *host;
+	struct pci_dev *pdev;
+
+	struct ufshcd_lrb *lrb;
+
+	unsigned long outstanding_tasks;
+	unsigned long outstanding_reqs;
+
+	u32 capabilities;
+	int nutrs;
+	int nutmrs;
+	u32 ufs_version;
+
+	struct uic_command active_uic_cmd;
+	wait_queue_head_t ufshcd_tm_wait_queue;
+	unsigned long tm_condition;
+
+	u32 ufshcd_state;
+	u32 int_enable_mask;
+
+	/* Work Queues */
+	struct work_struct uic_workq;
+	struct work_struct feh_workq;
+
+	/* HBA Errors */
+	u32 errors;
+};
+
+/**
+ * struct ufshcd_lrb - local reference block
+ * @utr_descriptor_ptr: UTRD address of the command
+ * @ucd_cmd_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
+ * @sense_buffer: pointer to sense buffer address of the SCSI command
+ * @sense_bufflen: Length of the sense buffer
+ * @scsi_status: SCSI status of the command
+ * @command_type: SCSI, UFS, Query.
+ * @task_tag: Task tag of the command
+ * @lun: LUN of the command
+ */
+struct ufshcd_lrb {
+	struct utp_transfer_req_desc *utr_descriptor_ptr;
+	struct utp_upiu_cmd *ucd_cmd_ptr;
+	struct utp_upiu_rsp *ucd_rsp_ptr;
+	struct ufshcd_sg_entry *ucd_prdt_ptr;
+
+	struct scsi_cmnd *cmd;
+	u8 *sense_buffer;
+	unsigned int sense_bufflen;
+	int scsi_status;
+
+	int command_type;
+	int task_tag;
+	unsigned int lun;
+};
+
+/**
+ * ufshcd_get_ufs_version - Get the UFS version supported by the HBA
+ * @hba - Pointer to adapter instance
+ *
+ * Returns UFSHCI version supported by the controller
+ */
+static inline u32 ufshcd_get_ufs_version(struct ufs_hba *hba)
+{
+	return readl(hba->mmio_base + REG_UFS_VERSION);
+}
+
+/**
+ * ufshcd_is_device_present - Check if any device connected to
+ *			      the host controller
+ * @reg_hcs - host controller status register value
+ *
+ * Returns 0 if device present, non-zero if no device detected
+ */
+static inline int ufshcd_is_device_present(u32 reg_hcs)
+{
+	return (DEVICE_PRESENT & reg_hcs) ? 0 : -1;
+}
+
+/**
+ * ufshcd_get_tr_ocs - Get the UTRD Overall Command Status
+ * @lrb: pointer to local command reference block
+ *
+ * This function is used to get the OCS field from UTRD
+ * Returns the OCS field in the UTRD
+ */
+static inline int ufshcd_get_tr_ocs(struct ufshcd_lrb *lrbp)
+{
+	return lrbp->utr_descriptor_ptr->header.dword_2 & MASK_OCS;
+}
+
+/**
+ * ufshcd_get_tmr_ocs - Get the UTMRD Overall Command Status
+ * @task_req_descp: pointer to utp_task_req_desc structure
+ *
+ * This function is used to get the OCS field from UTMRD
+ * Returns the OCS field in the UTMRD
+ */
+static inline int
+ufshcd_get_tmr_ocs(struct utp_task_req_desc *task_req_descp)
+{
+	return task_req_descp->header.dword_2 & MASK_OCS;
+}
+
+/**
+ * ufshcd_get_tm_free_slot - get a free slot for task management request
+ * @hba: per adapter instance
+ *
+ * Returns maximum number of task management request slots in case of
+ * task management queue full or returns the free slot number
+ */
+static inline int ufshcd_get_tm_free_slot(struct ufs_hba *hba)
+{
+	return find_first_zero_bit(&hba->outstanding_tasks, hba->nutmrs);
+}
+
+/**
+ * ufshcd_utrl_clear - Clear a bit in UTRLCLR register
+ * @hba: per adapter instance
+ * @pos: position of the bit to be cleared
+ */
+static inline void ufshcd_utrl_clear(struct ufs_hba *hba, u32 pos)
+{
+	writel(~(1 << pos),
+		(hba->mmio_base + REG_UTP_TRANSFER_REQ_LIST_CLEAR));
+}
+
+/**
+ * ufshcd_get_lists_status - Check UCRDY, UTRLRDY and UTMRLRDY
+ * @reg: Register value of host controller status
+ *
+ * Returns integer, 0 on Success and positive value if failed
+ */
+static inline int ufshcd_get_lists_status(u32 reg)
+{
+	/*
+	 * The mask 0xFF is for the following HCS register bits
+	 * Bit		Description
+	 *  0		Device Present
+	 *  1		UTRLRDY
+	 *  2		UTMRLRDY
+	 *  3		UCRDY
+	 *  4		HEI
+	 *  5		DEI
+	 * 6-7		reserved
+	 */
+	return (((reg) & (0xFF)) >> 1) ^ (0x07);
+}
+
+/**
+ * ufshcd_get_uic_cmd_result - Get the UIC command result
+ * @hba: Pointer to adapter instance
+ *
+ * This function gets the result of UIC command completion
+ * Returns 0 on success, non zero value on error
+ */
+static inline int ufshcd_get_uic_cmd_result(struct ufs_hba *hba)
+{
+	return readl(hba->mmio_base + REG_UIC_COMMAND_ARG_2) &
+	       MASK_UIC_COMMAND_RESULT;
+}
+
+/**
+ * ufshcd_free_hba_memory - Free allocated memory for LRB, request
+ *			    and task lists
+ * @hba: Pointer to adapter instance
+ */
+static inline void ufshcd_free_hba_memory(struct ufs_hba *hba)
+{
+	size_t utmrdl_size, utrdl_size, ucdl_size;
+
+	kfree(hba->lrb);
+
+	if (hba->utmrdl_base_addr) {
+		utmrdl_size = sizeof(struct utp_task_req_desc) * hba->nutmrs;
+		dma_free_coherent(&hba->pdev->dev, utmrdl_size,
+				  hba->utmrdl_base_addr, hba->utmrdl_dma_addr);
+	}
+
+	if (hba->utrdl_base_addr) {
+		utrdl_size =
+		(sizeof(struct utp_transfer_req_desc) * hba->nutrs);
+		dma_free_coherent(&hba->pdev->dev, utrdl_size,
+				  hba->utrdl_base_addr, hba->utrdl_dma_addr);
+	}
+
+	if (hba->ucdl_base_addr) {
+		ucdl_size =
+		(sizeof(struct utp_transfer_cmd_desc) * hba->nutrs);
+		dma_free_coherent(&hba->pdev->dev, ucdl_size,
+				  hba->ucdl_base_addr, hba->ucdl_dma_addr);
+	}
+}
+
+/**
+ * ufshcd_is_valid_req_rsp - checks if controller TR response is valid
+ * @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)
+{
+	return ((be32_to_cpu(ucd_rsp_ptr->header.dword_0) >> 24) ==
+		 UPIU_TRANSACTION_RESPONSE) ? 0 : DID_ERROR << 16;
+}
+
+/**
+ * ufshcd_get_rsp_upiu_result - Get the result from response UPIU
+ * @ucd_rsp_ptr: pointer to response UPIU
+ *
+ * This function gets the response status and scsi_status from response UPIU
+ * Returns the response result code.
+ */
+static inline int
+ufshcd_get_rsp_upiu_result(struct utp_upiu_rsp *ucd_rsp_ptr)
+{
+	return be32_to_cpu(ucd_rsp_ptr->header.dword_1) & MASK_RSP_UPIU_RESULT;
+}
+
+/**
+ * ufshcd_config_int_aggr - Configure interrupt aggregation values.
+ *		Currently there is no use case where we want to configure
+ *		interrupt aggregation dynamically. So to configure interrupt
+ *		aggregation, #define INT_AGGR_COUNTER_THRESHOLD_VALUE and
+ *		INT_AGGR_TIMEOUT_VALUE are used.
+ * @hba: per adapter instance
+ * @option: Interrupt aggregation option
+ */
+static inline void
+ufshcd_config_int_aggr(struct ufs_hba *hba, int option)
+{
+	switch (option) {
+	case INT_AGGR_RESET:
+		writel((INT_AGGR_ENABLE |
+			INT_AGGR_COUNTER_AND_TIMER_RESET),
+			(hba->mmio_base +
+			 REG_UTP_TRANSFER_REQ_INT_AGG_CONTROL));
+		break;
+	case INT_AGGR_CONFIG:
+		writel((INT_AGGR_ENABLE |
+			INT_AGGR_PARAM_WRITE |
+			INT_AGGR_COUNTER_THRESHOLD_VALUE |
+			INT_AGGR_TIMEOUT_VALUE),
+			(hba->mmio_base +
+			 REG_UTP_TRANSFER_REQ_INT_AGG_CONTROL));
+		break;
+	}
+}
+
+/**
+ * ufshcd_enable_run_stop_reg - Enable run-stop registers,
+ *			When run-stop registers are set to 1, it indicates the
+ *			host controller that it can process the requests
+ * @hba: per adapter instance
+ */
+static void ufshcd_enable_run_stop_reg(struct ufs_hba *hba)
+{
+	writel(UTP_TASK_REQ_LIST_RUN_STOP_BIT,
+	       (hba->mmio_base +
+		REG_UTP_TASK_REQ_LIST_RUN_STOP));
+	writel(UTP_TRANSFER_REQ_LIST_RUN_STOP_BIT,
+	       (hba->mmio_base +
+		REG_UTP_TRANSFER_REQ_LIST_RUN_STOP));
+}
+
+/**
+ * ufshcd_hba_stop - Send controller to reset state
+ * @hba: per adapter instance
+ */
+static inline void ufshcd_hba_stop(struct ufs_hba *hba)
+{
+	writel(CONTROLLER_DISABLE, (hba->mmio_base + REG_CONTROLLER_ENABLE));
+}
+
+/**
+ * ufshcd_hba_start - Start controller initialization sequence
+ * @hba: per adapter instance
+ */
+static inline void ufshcd_hba_start(struct ufs_hba *hba)
+{
+	writel(CONTROLLER_ENABLE , (hba->mmio_base + REG_CONTROLLER_ENABLE));
+}
+
+/**
+ * ufshcd_is_hba_active - Get controller state
+ * @hba: per adapter instance
+ *
+ * Returns zero if controller is active, 1 otherwise
+ */
+static inline int ufshcd_is_hba_active(struct ufs_hba *hba)
+{
+	return (readl(hba->mmio_base + REG_CONTROLLER_ENABLE) & 0x1) ? 0 : 1;
+}
+
+/**
+ * ufshcd_send_command - Send SCSI or device management commands
+ * @hba: per adapter instance
+ * @task_tag: Task tag of the command
+ */
+static inline
+void ufshcd_send_command(struct ufs_hba *hba, unsigned int task_tag)
+{
+	__set_bit(task_tag, &hba->outstanding_reqs);
+	writel((1 << task_tag),
+	       (hba->mmio_base + REG_UTP_TRANSFER_REQ_DOOR_BELL));
+}
+
+/**
+ * ufshcd_copy_sense_data - Copy sense data in case of check condition
+ * @lrb - pointer to local reference block
+ */
+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);
+		memcpy(lrbp->sense_buffer,
+			lrbp->ucd_rsp_ptr->sense_data,
+			min_t(int, len, SCSI_SENSE_BUFFERSIZE));
+	}
+}
+
+/**
+ * ufshcd_hba_capabilities - Read controller capabilities
+ * @hba: per adapter instance
+ */
+static inline void ufshcd_hba_capabilities(struct ufs_hba *hba)
+{
+	hba->capabilities =
+		readl(hba->mmio_base + REG_CONTROLLER_CAPABILITIES);
+
+	/* nutrs and nutmrs are 0 based values */
+	hba->nutrs = (hba->capabilities & MASK_TRANSFER_REQUESTS_SLOTS) + 1;
+	hba->nutmrs =
+	((hba->capabilities & MASK_TASK_MANAGEMENT_REQUEST_SLOTS) >> 16) + 1;
+}
+
+/**
+ * ufshcd_send_uic_command - Send UIC commands to unipro layers
+ * @hba: per adapter instance
+ * @uic_command: UIC command
+ */
+static inline void
+ufshcd_send_uic_command(struct ufs_hba *hba, struct uic_command *uic_cmnd)
+{
+	/* Write Args */
+	writel(uic_cmnd->argument1,
+	      (hba->mmio_base + REG_UIC_COMMAND_ARG_1));
+	writel(uic_cmnd->argument2,
+	      (hba->mmio_base + REG_UIC_COMMAND_ARG_2));
+	writel(uic_cmnd->argument3,
+	      (hba->mmio_base + REG_UIC_COMMAND_ARG_3));
+
+	/* Write UIC Cmd */
+	writel((uic_cmnd->command & COMMAND_OPCODE_MASK),
+	       (hba->mmio_base + REG_UIC_COMMAND));
+}
+
+/**
+ * ufshcd_map_sg - Map scatter-gather list to prdt
+ * @lrbp - pointer to local reference block
+ *
+ * Returns 0 in case of success, non-zero value in case of failure
+ */
+static int ufshcd_map_sg(struct ufshcd_lrb *lrbp)
+{
+	struct ufshcd_sg_entry *prd_table;
+	struct scatterlist *sg;
+	struct scsi_cmnd *cmd;
+	int sg_segments;
+	int i;
+
+	cmd = lrbp->cmd;
+	sg_segments = scsi_dma_map(cmd);
+	if (sg_segments < 0)
+		return sg_segments;
+
+	if (sg_segments) {
+		lrbp->utr_descriptor_ptr->prd_table_length =
+					cpu_to_le16((u16) (sg_segments));
+
+		prd_table = (struct ufshcd_sg_entry *)lrbp->ucd_prdt_ptr;
+
+		scsi_for_each_sg(cmd, sg, sg_segments, i) {
+			prd_table[i].size  =
+				cpu_to_le32(((u32) sg_dma_len(sg))-1);
+			prd_table[i].base_addr =
+				cpu_to_le32(lower_32_bits(sg->dma_address));
+			prd_table[i].upper_addr =
+				cpu_to_le32(upper_32_bits(sg->dma_address));
+		}
+	} else {
+		lrbp->utr_descriptor_ptr->prd_table_length = 0;
+	}
+
+	return 0;
+}
+
+/**
+ * ufshcd_int_config - enable/disable interrupts
+ * @hba: per adapter instance
+ * @option: interrupt option
+ */
+static void ufshcd_int_config(struct ufs_hba *hba, u32 option)
+{
+	switch (option) {
+	case UFSHCD_INT_ENABLE:
+		writel(hba->int_enable_mask,
+		      (hba->mmio_base + REG_INTERRUPT_ENABLE));
+		break;
+	case UFSHCD_INT_DISABLE:
+		if (hba->ufs_version == UFSHCI_VERSION_10)
+			writel(INTERRUPT_DISABLE_MASK_10,
+			      (hba->mmio_base + REG_INTERRUPT_ENABLE));
+		else
+			writel(INTERRUPT_DISABLE_MASK_11,
+			       (hba->mmio_base + REG_INTERRUPT_ENABLE));
+		break;
+	}
+}
+
+/**
+ * ufshcd_compose_upiu - form UFS Protocol Information Unit(UPIU)
+ * @lrb - pointer to local reference block
+ */
+static void ufshcd_compose_upiu(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;
+
+	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;
+		} else {
+			data_direction = UTP_NO_DATA_TRANSFER;
+			upiu_flags = UPIU_CMD_FLAGS_NONE;
+		}
+
+		/* 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->transfersize);
+
+		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 */
+		break;
+	case UTP_CMD_TYPE_UFS:
+		/* For UFS native command implementation */
+		break;
+	} /* end of switch */
+}
+
+/**
+ * ufshcd_queuecommand - main entry point for SCSI requests
+ * @cmd: command from SCSI Midlayer
+ * @done: call back function
+ *
+ * Returns 0 for success, non-zero in case of failure
+ */
+static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
+{
+	struct ufshcd_lrb *lrbp;
+	struct ufs_hba *hba;
+	unsigned long flags;
+	int tag;
+	int err = 0;
+
+	hba = shost_priv(host);
+
+	tag = cmd->request->tag;
+
+	if (hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL) {
+		err = SCSI_MLQUEUE_HOST_BUSY;
+		goto out;
+	}
+
+	lrbp = &hba->lrb[tag];
+
+	lrbp->cmd = cmd;
+	lrbp->sense_bufflen = SCSI_SENSE_BUFFERSIZE;
+	lrbp->sense_buffer = cmd->sense_buffer;
+	lrbp->task_tag = tag;
+	lrbp->lun = cmd->device->lun;
+
+	lrbp->command_type = UTP_CMD_TYPE_SCSI;
+
+	/* form UPIU before issuing the command */
+	ufshcd_compose_upiu(lrbp);
+	err = ufshcd_map_sg(lrbp);
+	if (err)
+		goto out;
+
+	/* issue command to the controller */
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	ufshcd_send_command(hba, tag);
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+out:
+	return err;
+}
+
+/**
+ * ufshcd_memory_alloc - allocate memory for host memory space data structures
+ * @hba: per adapter instance
+ *
+ * 1. Allocate DMA memory for Command Descriptor array
+ *	Each command descriptor consist of Command UPIU, Response UPIU and PRDT
+ * 2. Allocate DMA memory for UTP Transfer Request Descriptor List (UTRDL).
+ * 3. Allocate DMA memory for UTP Task Management Request Descriptor List
+ *	(UTMRDL)
+ * 4. Allocate memory for local reference block(lrb).
+ *
+ * Returns 0 for success, non-zero in case of failure
+ */
+static int ufshcd_memory_alloc(struct ufs_hba *hba)
+{
+	size_t utmrdl_size, utrdl_size, ucdl_size;
+
+	/* Allocate memory for UTP command descriptors */
+	ucdl_size = (sizeof(struct utp_transfer_cmd_desc) * hba->nutrs);
+	hba->ucdl_base_addr = dma_alloc_coherent(&hba->pdev->dev,
+						 ucdl_size,
+						 &hba->ucdl_dma_addr,
+						 GFP_KERNEL);
+
+	/*
+	 * UFSHCI requires UTP command descriptor to be 128 byte aligned.
+	 * make sure hba->ucdl_dma_addr is aligned to PAGE_SIZE
+	 * if hba->ucdl_dma_addr is aligned to PAGE_SIZE, then it will
+	 * be aligned to 128 bytes as well
+	 */
+	if (!hba->ucdl_base_addr ||
+	    WARN_ON(hba->ucdl_dma_addr & (PAGE_SIZE - 1))) {
+		dev_err(&hba->pdev->dev,
+			"Command Descriptor Memory allocation failed\n");
+		goto out;
+	}
+
+	/*
+	 * Allocate memory for UTP Transfer descriptors
+	 * UFSHCI requires 1024 byte alignment of UTRD
+	 */
+	utrdl_size = (sizeof(struct utp_transfer_req_desc) * hba->nutrs);
+	hba->utrdl_base_addr = dma_alloc_coherent(&hba->pdev->dev,
+						  utrdl_size,
+						  &hba->utrdl_dma_addr,
+						  GFP_KERNEL);
+	if (!hba->utrdl_base_addr ||
+	    WARN_ON(hba->utrdl_dma_addr & (PAGE_SIZE - 1))) {
+		dev_err(&hba->pdev->dev,
+			"Transfer Descriptor Memory allocation failed\n");
+		goto out;
+	}
+
+	/*
+	 * Allocate memory for UTP Task Management descriptors
+	 * UFSHCI requires 1024 byte alignment of UTMRD
+	 */
+	utmrdl_size = sizeof(struct utp_task_req_desc) * hba->nutmrs;
+	hba->utmrdl_base_addr = dma_alloc_coherent(&hba->pdev->dev,
+						   utmrdl_size,
+						   &hba->utmrdl_dma_addr,
+						   GFP_KERNEL);
+	if (!hba->utmrdl_base_addr ||
+	    WARN_ON(hba->utmrdl_dma_addr & (PAGE_SIZE - 1))) {
+		dev_err(&hba->pdev->dev,
+		"Task Management Descriptor Memory allocation failed\n");
+		goto out;
+	}
+
+	/* Allocate memory for local reference block */
+	hba->lrb = kcalloc(hba->nutrs, sizeof(struct ufshcd_lrb), GFP_KERNEL);
+	if (!hba->lrb) {
+		dev_err(&hba->pdev->dev, "LRB Memory allocation failed\n");
+		goto out;
+	}
+	return 0;
+out:
+	ufshcd_free_hba_memory(hba);
+	return -ENOMEM;
+}
+
+/**
+ * ufshcd_host_memory_configure - configure local reference block with
+ *				memory offsets
+ * @hba: per adapter instance
+ *
+ * Configure Host memory space
+ * 1. Update Corresponding UTRD.UCDBA and UTRD.UCDBAU with UCD DMA
+ * address.
+ * 2. Update each UTRD with Response UPIU offset, Response UPIU length
+ * and PRDT offset.
+ * 3. Save the corresponding addresses of UTRD, UCD.CMD, UCD.RSP and UCD.PRDT
+ * into local reference block.
+ */
+static void ufshcd_host_memory_configure(struct ufs_hba *hba)
+{
+	struct utp_transfer_cmd_desc *cmd_descp;
+	struct utp_transfer_req_desc *utrdlp;
+	dma_addr_t cmd_desc_dma_addr;
+	dma_addr_t cmd_desc_element_addr;
+	u16 response_offset;
+	u16 prdt_offset;
+	int cmd_desc_size;
+	int i;
+
+	utrdlp = hba->utrdl_base_addr;
+	cmd_descp = hba->ucdl_base_addr;
+
+	response_offset =
+		offsetof(struct utp_transfer_cmd_desc, response_upiu);
+	prdt_offset =
+		offsetof(struct utp_transfer_cmd_desc, prd_table);
+
+	cmd_desc_size = sizeof(struct utp_transfer_cmd_desc);
+	cmd_desc_dma_addr = hba->ucdl_dma_addr;
+
+	for (i = 0; i < hba->nutrs; i++) {
+		/* Configure UTRD with command descriptor base address */
+		cmd_desc_element_addr =
+				(cmd_desc_dma_addr + (cmd_desc_size * i));
+		utrdlp[i].command_desc_base_addr_lo =
+				cpu_to_le32(lower_32_bits(cmd_desc_element_addr));
+		utrdlp[i].command_desc_base_addr_hi =
+				cpu_to_le32(upper_32_bits(cmd_desc_element_addr));
+
+		/* Response upiu and prdt offset should be in double words */
+		utrdlp[i].response_upiu_offset =
+				cpu_to_le16((response_offset >> 2));
+		utrdlp[i].prd_table_offset =
+				cpu_to_le16((prdt_offset >> 2));
+		utrdlp[i].response_upiu_length =
+				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_rsp_ptr =
+			(struct utp_upiu_rsp *)cmd_descp[i].response_upiu;
+		hba->lrb[i].ucd_prdt_ptr =
+			(struct ufshcd_sg_entry *)cmd_descp[i].prd_table;
+	}
+}
+
+/**
+ * ufshcd_dme_link_startup - Notify Unipro to perform link startup
+ * @hba: per adapter instance
+ *
+ * UIC_CMD_DME_LINK_STARTUP command must be issued to Unipro layer,
+ * in order to initialize the Unipro link startup procedure.
+ * Once the Unipro links are up, the device connected to the controller
+ * is detected.
+ *
+ * Returns 0 on success, non-zero value on failure
+ */
+static int ufshcd_dme_link_startup(struct ufs_hba *hba)
+{
+	struct uic_command *uic_cmd;
+	unsigned long flags;
+
+	/* check if controller is ready to accept UIC commands */
+	if (((readl(hba->mmio_base + REG_CONTROLLER_STATUS)) &
+	    UIC_COMMAND_READY) == 0x0) {
+		dev_err(&hba->pdev->dev,
+			"Controller not ready"
+			" to accept UIC commands\n");
+		return -EIO;
+	}
+
+	spin_lock_irqsave(hba->host->host_lock, flags);
+
+	/* form UIC command */
+	uic_cmd = &hba->active_uic_cmd;
+	uic_cmd->command = UIC_CMD_DME_LINK_STARTUP;
+	uic_cmd->argument1 = 0;
+	uic_cmd->argument2 = 0;
+	uic_cmd->argument3 = 0;
+
+	/* enable UIC related interrupts */
+	hba->int_enable_mask |= UIC_COMMAND_COMPL;
+	ufshcd_int_config(hba, UFSHCD_INT_ENABLE);
+
+	/* sending UIC commands to controller */
+	ufshcd_send_uic_command(hba, uic_cmd);
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+	return 0;
+}
+
+/**
+ * ufshcd_make_hba_operational - Make UFS controller operational
+ * @hba: per adapter instance
+ *
+ * To bring UFS host controller to operational state,
+ * 1. Check if device is present
+ * 2. Configure run-stop-registers
+ * 3. Enable required interrupts
+ * 4. Configure interrupt aggregation
+ *
+ * Returns 0 on success, non-zero value on failure
+ */
+static int ufshcd_make_hba_operational(struct ufs_hba *hba)
+{
+	int err = 0;
+	u32 reg;
+
+	/* check if device present */
+	reg = readl((hba->mmio_base + REG_CONTROLLER_STATUS));
+	if (ufshcd_is_device_present(reg)) {
+		dev_err(&hba->pdev->dev, "cc: Device not present\n");
+		err = -ENXIO;
+		goto out;
+	}
+
+	/*
+	 * UCRDY, UTMRLDY and UTRLRDY bits must be 1
+	 * DEI, HEI bits must be 0
+	 */
+	if (!(ufshcd_get_lists_status(reg))) {
+		ufshcd_enable_run_stop_reg(hba);
+	} else {
+		dev_err(&hba->pdev->dev,
+			"Host controller not ready to process requests");
+		err = -EIO;
+		goto out;
+	}
+
+	/* Enable required interrupts */
+	hba->int_enable_mask |= (UTP_TRANSFER_REQ_COMPL |
+				 UIC_ERROR |
+				 UTP_TASK_REQ_COMPL |
+				 DEVICE_FATAL_ERROR |
+				 CONTROLLER_FATAL_ERROR |
+				 SYSTEM_BUS_FATAL_ERROR);
+	ufshcd_int_config(hba, UFSHCD_INT_ENABLE);
+
+	/* Configure interrupt aggregation */
+	ufshcd_config_int_aggr(hba, INT_AGGR_CONFIG);
+
+	if (hba->ufshcd_state == UFSHCD_STATE_RESET)
+		scsi_unblock_requests(hba->host);
+
+	hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
+	scsi_scan_host(hba->host);
+out:
+	return err;
+}
+
+/**
+ * ufshcd_hba_enable - initialize the controller
+ * @hba: per adapter instance
+ *
+ * The controller resets itself and controller firmware initialization
+ * sequence kicks off. When controller is ready it will set
+ * the Host Controller Enable bit to 1.
+ *
+ * Returns 0 on success, non-zero value on failure
+ */
+static int ufshcd_hba_enable(struct ufs_hba *hba)
+{
+	int retry;
+
+	/*
+	 * msleep of 1 and 5 used in this function might result in msleep(20),
+	 * but it was necessary to send the UFS FPGA to reset mode during
+	 * development and testing of this driver. msleep can be changed to
+	 * mdelay and retry count can be reduced based on the controller.
+	 */
+	if (!ufshcd_is_hba_active(hba)) {
+
+		/* change controller state to "reset state" */
+		ufshcd_hba_stop(hba);
+
+		/*
+		 * This delay is based on the testing done with UFS host
+		 * controller FPGA. The delay can be changed based on the
+		 * host controller used.
+		 */
+		msleep(5);
+	}
+
+	/* start controller initialization sequence */
+	ufshcd_hba_start(hba);
+
+	/*
+	 * To initialize a UFS host controller HCE bit must be set to 1.
+	 * During initialization the HCE bit value changes from 1->0->1.
+	 * When the host controller completes initialization sequence
+	 * it sets the value of HCE bit to 1. The same HCE bit is read back
+	 * to check if the controller has completed initialization sequence.
+	 * So without this delay the value HCE = 1, set in the previous
+	 * instruction might be read back.
+	 * This delay can be changed based on the controller.
+	 */
+	msleep(1);
+
+	/* wait for the host controller to complete initialization */
+	retry = 10;
+	while (ufshcd_is_hba_active(hba)) {
+		if (retry) {
+			retry--;
+		} else {
+			dev_err(&hba->pdev->dev,
+				"Controller enable failed\n");
+			return -EIO;
+		}
+		msleep(5);
+	}
+	return 0;
+}
+
+/**
+ * ufshcd_initialize_hba - start the initialization process
+ * @hba: per adapter instance
+ *
+ * 1. Enable the controller via ufshcd_hba_enable.
+ * 2. Program the Transfer Request List Address with the starting address of
+ * UTRDL.
+ * 3. Program the Task Management Request List Address with starting address
+ * of UTMRDL.
+ *
+ * Returns 0 on success, non-zero value on failure.
+ */
+static int ufshcd_initialize_hba(struct ufs_hba *hba)
+{
+	if (ufshcd_hba_enable(hba))
+		return -EIO;
+
+	/* Configure UTRL and UTMRL base address registers */
+	writel(hba->utrdl_dma_addr,
+	       (hba->mmio_base + REG_UTP_TRANSFER_REQ_LIST_BASE_L));
+	writel(lower_32_bits(hba->utrdl_dma_addr),
+	       (hba->mmio_base + REG_UTP_TRANSFER_REQ_LIST_BASE_H));
+	writel(hba->utmrdl_dma_addr,
+	       (hba->mmio_base + REG_UTP_TASK_REQ_LIST_BASE_L));
+	writel(upper_32_bits(hba->utmrdl_dma_addr),
+	       (hba->mmio_base + REG_UTP_TASK_REQ_LIST_BASE_H));
+
+	/* Initialize unipro link startup procedure */
+	return ufshcd_dme_link_startup(hba);
+}
+
+/**
+ * ufshcd_do_reset - reset the host controller
+ * @hba: per adapter instance
+ *
+ * Returns SUCCESS/FAILED
+ */
+static int ufshcd_do_reset(struct ufs_hba *hba)
+{
+	struct ufshcd_lrb *lrbp;
+	unsigned long flags;
+	int tag;
+
+	/* block commands from midlayer */
+	scsi_block_requests(hba->host);
+
+	spin_lock_irqsave(hba->host->host_lock, flags);
+	hba->ufshcd_state = UFSHCD_STATE_RESET;
+
+	/* send controller to reset state */
+	ufshcd_hba_stop(hba);
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+	/* abort outstanding commands */
+	for (tag = 0; tag < hba->nutrs; 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;
+		}
+	}
+
+	/* clear outstanding request/task bit maps */
+	hba->outstanding_reqs = 0;
+	hba->outstanding_tasks = 0;
+
+	/* start the initialization process */
+	if (ufshcd_initialize_hba(hba)) {
+		dev_err(&hba->pdev->dev,
+			"Reset: Controller initialization failed\n");
+		return FAILED;
+	}
+	return SUCCESS;
+}
+
+/**
+ * ufshcd_slave_alloc - handle initial SCSI device configurations
+ * @sdev: pointer to SCSI device
+ *
+ * Returns success
+ */
+static int ufshcd_slave_alloc(struct scsi_device *sdev)
+{
+	struct ufs_hba *hba;
+
+	hba = shost_priv(sdev->host);
+	sdev->tagged_supported = 1;
+
+	/* Mode sense(6) is not supported by UFS, so use Mode sense(10) */
+	sdev->use_10_for_ms = 1;
+	scsi_set_tag_type(sdev, MSG_SIMPLE_TAG);
+
+	/*
+	 * Inform SCSI Midlayer that the LUN queue depth is same as the
+	 * controller queue depth. If a LUN queue depth is less than the
+	 * controller queue depth and if the LUN reports
+	 * SAM_STAT_TASK_SET_FULL, the LUN queue depth will be adjusted
+	 * with scsi_adjust_queue_depth.
+	 */
+	scsi_activate_tcq(sdev, hba->nutrs);
+	return 0;
+}
+
+/**
+ * ufshcd_slave_destroy - remove SCSI device configurations
+ * @sdev: pointer to SCSI device
+ */
+static void ufshcd_slave_destroy(struct scsi_device *sdev)
+{
+	struct ufs_hba *hba;
+
+	hba = shost_priv(sdev->host);
+	scsi_deactivate_tcq(sdev, hba->nutrs);
+}
+
+/**
+ * ufshcd_task_req_compl - handle task management request completion
+ * @hba: per adapter instance
+ * @index: index of the completed request
+ *
+ * Returns SUCCESS/FAILED
+ */
+static int ufshcd_task_req_compl(struct ufs_hba *hba, u32 index)
+{
+	struct utp_task_req_desc *task_req_descp;
+	struct utp_upiu_task_rsp *task_rsp_upiup;
+	unsigned long flags;
+	int ocs_value;
+	int task_result;
+
+	spin_lock_irqsave(hba->host->host_lock, flags);
+
+	/* Clear completed tasks from outstanding_tasks */
+	__clear_bit(index, &hba->outstanding_tasks);
+
+	task_req_descp = hba->utmrdl_base_addr;
+	ocs_value = ufshcd_get_tmr_ocs(&task_req_descp[index]);
+
+	if (ocs_value == OCS_SUCCESS) {
+		task_rsp_upiup = (struct utp_upiu_task_rsp *)
+				task_req_descp[index].task_rsp_upiu;
+		task_result = be32_to_cpu(task_rsp_upiup->header.dword_1);
+		task_result = ((task_result & MASK_TASK_RESPONSE) >> 8);
+
+		if (task_result != UPIU_TASK_MANAGEMENT_FUNC_COMPL ||
+		    task_result != UPIU_TASK_MANAGEMENT_FUNC_SUCCEEDED)
+			task_result = FAILED;
+	} else {
+		task_result = FAILED;
+		dev_err(&hba->pdev->dev,
+			"trc: Invalid ocs = %x\n", ocs_value);
+	}
+	spin_unlock_irqrestore(hba->host->host_lock, flags);
+	return task_result;
+}
+
+/**
+ * ufshcd_adjust_lun_qdepth - Update LUN queue depth if device responds with
+ *			      SAM_STAT_TASK_SET_FULL SCSI command status.
+ * @cmd: pointer to SCSI command
+ */
+static void ufshcd_adjust_lun_qdepth(struct scsi_cmnd *cmd)
+{
+	struct ufs_hba *hba;
+	int i;
+	int lun_qdepth = 0;
+
+	hba = shost_priv(cmd->device->host);
+
+	/*
+	 * LUN queue depth can be obtained by counting outstanding commands
+	 * on the LUN.
+	 */
+	for (i = 0; i < hba->nutrs; i++) {
+		if (test_bit(i, &hba->outstanding_reqs)) {
+
+			/*
+			 * Check if the outstanding command belongs
+			 * to the LUN which reported SAM_STAT_TASK_SET_FULL.
+			 */
+			if (cmd->device->lun == hba->lrb[i].lun)
+				lun_qdepth++;
+		}
+	}
+
+	/*
+	 * LUN queue depth will be total outstanding commands, except the
+	 * command for which the LUN reported SAM_STAT_TASK_SET_FULL.
+	 */
+	scsi_adjust_queue_depth(cmd->device, MSG_SIMPLE_TAG, lun_qdepth - 1);
+}
+
+/**
+ * ufshcd_scsi_cmd_status - Update SCSI command result based on SCSI status
+ * @lrb: pointer to local reference block of completed command
+ * @scsi_status: SCSI command status
+ *
+ * Returns value base on SCSI command status
+ */
+static inline int
+ufshcd_scsi_cmd_status(struct ufshcd_lrb *lrbp, int scsi_status)
+{
+	int result = 0;
+
+	switch (scsi_status) {
+	case SAM_STAT_GOOD:
+		result |= DID_OK << 16 |
+			  COMMAND_COMPLETE << 8 |
+			  SAM_STAT_GOOD;
+		break;
+	case SAM_STAT_CHECK_CONDITION:
+		result |= DID_OK << 16 |
+			  COMMAND_COMPLETE << 8 |
+			  SAM_STAT_CHECK_CONDITION;
+		ufshcd_copy_sense_data(lrbp);
+		break;
+	case SAM_STAT_BUSY:
+		result |= SAM_STAT_BUSY;
+		break;
+	case SAM_STAT_TASK_SET_FULL:
+
+		/*
+		 * If a LUN reports SAM_STAT_TASK_SET_FULL, then the LUN queue
+		 * depth needs to be adjusted to the exact number of
+		 * outstanding commands the LUN can handle at any given time.
+		 */
+		ufshcd_adjust_lun_qdepth(lrbp->cmd);
+		result |= SAM_STAT_TASK_SET_FULL;
+		break;
+	case SAM_STAT_TASK_ABORTED:
+		result |= SAM_STAT_TASK_ABORTED;
+		break;
+	default:
+		result |= DID_ERROR << 16;
+		break;
+	} /* end of switch */
+
+	return result;
+}
+
+/**
+ * ufshcd_transfer_rsp_status - Get overall status of the response
+ * @hba: per adapter instance
+ * @lrb: pointer to local reference block of completed command
+ *
+ * Returns result of the command to notify SCSI midlayer
+ */
+static inline int
+ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
+{
+	int result = 0;
+	int scsi_status;
+	int ocs;
+
+	/* overall command status of utrd */
+	ocs = ufshcd_get_tr_ocs(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) {
+			dev_err(&hba->pdev->dev,
+				"Invalid response = %x\n", result);
+			break;
+		}
+
+		/*
+		 * 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;
+		break;
+	case OCS_INVALID_CMD_TABLE_ATTR:
+	case OCS_INVALID_PRDT_ATTR:
+	case OCS_MISMATCH_DATA_BUF_SIZE:
+	case OCS_MISMATCH_RESP_UPIU_SIZE:
+	case OCS_PEER_COMM_FAILURE:
+	case OCS_FATAL_ERROR:
+	default:
+		result |= DID_ERROR << 16;
+		dev_err(&hba->pdev->dev,
+		"OCS error from controller = %x\n", ocs);
+		break;
+	} /* end of switch */
+
+	return result;
+}
+
+/**
+ * ufshcd_transfer_req_compl - handle SCSI and query command completion
+ * @hba: per adapter instance
+ */
+static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
+{
+	struct ufshcd_lrb *lrb;
+	unsigned long completed_reqs;
+	u32 tr_doorbell;
+	int result;
+	int index;
+
+	lrb = hba->lrb;
+	tr_doorbell =
+		readl(hba->mmio_base + 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)) {
+
+			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);
+
+				/* Mark completed command as NULL in LRB */
+				lrb[index].cmd = NULL;
+			}
+		} /* end of if */
+	} /* end of for */
+
+	/* clear corresponding bits of completed commands */
+	hba->outstanding_reqs ^= completed_reqs;
+
+	/* Reset interrupt aggregation counters */
+	ufshcd_config_int_aggr(hba, INT_AGGR_RESET);
+}
+
+/**
+ * ufshcd_uic_cc_handler - handle UIC command completion
+ * @work: pointer to a work queue structure
+ *
+ * Returns 0 on success, non-zero value on failure
+ */
+static void ufshcd_uic_cc_handler (struct work_struct *work)
+{
+	struct ufs_hba *hba;
+
+	hba = container_of(work, struct ufs_hba, uic_workq);
+
+	if ((hba->active_uic_cmd.command == UIC_CMD_DME_LINK_STARTUP) &&
+	    !(ufshcd_get_uic_cmd_result(hba))) {
+
+		if (ufshcd_make_hba_operational(hba))
+			dev_err(&hba->pdev->dev,
+				"cc: hba not operational state\n");
+		return;
+	}
+}
+
+/**
+ * ufshcd_fatal_err_handler - handle fatal errors
+ * @hba: per adapter instance
+ */
+static void ufshcd_fatal_err_handler(struct work_struct *work)
+{
+	struct ufs_hba *hba;
+	hba = container_of(work, struct ufs_hba, feh_workq);
+
+	/* check if reset is already in progress */
+	if (hba->ufshcd_state != UFSHCD_STATE_RESET)
+		ufshcd_do_reset(hba);
+}
+
+/**
+ * ufshcd_err_handler - Check for fatal errors
+ * @work: pointer to a work queue structure
+ */
+static void ufshcd_err_handler(struct ufs_hba *hba)
+{
+	u32 reg;
+
+	if (hba->errors & INT_FATAL_ERRORS)
+		goto fatal_eh;
+
+	if (hba->errors & UIC_ERROR) {
+
+		reg = readl(hba->mmio_base +
+			    REG_UIC_ERROR_CODE_PHY_ADAPTER_LAYER);
+		if (reg & UIC_DATA_LINK_LAYER_ERROR_PA_INIT)
+			goto fatal_eh;
+	}
+	return;
+fatal_eh:
+	hba->ufshcd_state = UFSHCD_STATE_ERROR;
+	schedule_work(&hba->feh_workq);
+}
+
+/**
+ * ufshcd_tmc_handler - handle task management function completion
+ * @hba: per adapter instance
+ */
+static void ufshcd_tmc_handler(struct ufs_hba *hba)
+{
+	u32 tm_doorbell;
+
+	tm_doorbell = readl(hba->mmio_base + REG_UTP_TASK_REQ_DOOR_BELL);
+	hba->tm_condition = tm_doorbell ^ hba->outstanding_tasks;
+	wake_up_interruptible(&hba->ufshcd_tm_wait_queue);
+}
+
+/**
+ * ufshcd_sl_intr - Interrupt service routine
+ * @hba: per adapter instance
+ * @intr_status: contains interrupts generated by the controller
+ */
+static void ufshcd_sl_intr(struct ufs_hba *hba, u32 intr_status)
+{
+	hba->errors = UFSHCD_ERROR_MASK & intr_status;
+	if (hba->errors)
+		ufshcd_err_handler(hba);
+
+	if (intr_status & UIC_COMMAND_COMPL)
+		schedule_work(&hba->uic_workq);
+
+	if (intr_status & UTP_TASK_REQ_COMPL)
+		ufshcd_tmc_handler(hba);
+
+	if (intr_status & UTP_TRANSFER_REQ_COMPL)
+		ufshcd_transfer_req_compl(hba);
+}
+
+/**
+ * ufshcd_intr - Main interrupt service routine
+ * @irq: irq number
+ * @__hba: pointer to adapter instance
+ *
+ * Returns IRQ_HANDLED - If interrupt is valid
+ *		IRQ_NONE - If invalid interrupt
+ */
+static irqreturn_t ufshcd_intr(int irq, void *__hba)
+{
+	u32 intr_status;
+	irqreturn_t retval = IRQ_NONE;
+	struct ufs_hba *hba = __hba;
+
+	spin_lock(hba->host->host_lock);
+	intr_status = readl(hba->mmio_base + REG_INTERRUPT_STATUS);
+
+	if (intr_status) {
+		ufshcd_sl_intr(hba, intr_status);
+
+		/* If UFSHCI 1.0 then clear interrupt status register */
+		if (hba->ufs_version == UFSHCI_VERSION_10)
+			writel(intr_status,
+			       (hba->mmio_base + REG_INTERRUPT_STATUS));
+		retval = IRQ_HANDLED;
+	}
+	spin_unlock(hba->host->host_lock);
+	return retval;
+}
+
+/**
+ * ufshcd_issue_tm_cmd - issues task management commands to controller
+ * @hba: per adapter instance
+ * @lrbp: pointer to local reference block
+ *
+ * Returns SUCCESS/FAILED
+ */
+static int
+ufshcd_issue_tm_cmd(struct ufs_hba *hba,
+		    struct ufshcd_lrb *lrbp,
+		    u8 tm_function)
+{
+	struct utp_task_req_desc *task_req_descp;
+	struct utp_upiu_task_req *task_req_upiup;
+	struct Scsi_Host *host;
+	unsigned long flags;
+	int free_slot = 0;
+	int err;
+
+	host = hba->host;
+
+	spin_lock_irqsave(host->host_lock, flags);
+
+	/* If task management queue is full */
+	free_slot = ufshcd_get_tm_free_slot(hba);
+	if (free_slot >= hba->nutmrs) {
+		spin_unlock_irqrestore(host->host_lock, flags);
+		dev_err(&hba->pdev->dev, "Task management queue full\n");
+		err = FAILED;
+		goto out;
+	}
+
+	task_req_descp = hba->utmrdl_base_addr;
+	task_req_descp += free_slot;
+
+	/* Configure task request descriptor */
+	task_req_descp->header.dword_0 = cpu_to_le32(UTP_REQ_DESC_INT_CMD);
+	task_req_descp->header.dword_2 =
+			cpu_to_le32(OCS_INVALID_COMMAND_STATUS);
+
+	/* Configure task request UPIU */
+	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));
+	task_req_upiup->header.dword_1 =
+	cpu_to_be32(UPIU_HEADER_DWORD(0, tm_function, 0, 0));
+
+	task_req_upiup->input_param1 = lrbp->lun;
+	task_req_upiup->input_param1 =
+		cpu_to_be32(task_req_upiup->input_param1);
+	task_req_upiup->input_param2 = lrbp->task_tag;
+	task_req_upiup->input_param2 =
+		cpu_to_be32(task_req_upiup->input_param2);
+
+	/* send command to the controller */
+	__set_bit(free_slot, &hba->outstanding_tasks);
+	writel((1 << free_slot),
+	       (hba->mmio_base + REG_UTP_TASK_REQ_DOOR_BELL));
+
+	spin_unlock_irqrestore(host->host_lock, flags);
+
+	/* wait until the task management command is completed */
+	err =
+	wait_event_interruptible_timeout(hba->ufshcd_tm_wait_queue,
+					 (test_bit(free_slot,
+					 &hba->tm_condition) != 0),
+					 60 * HZ);
+	if (!err) {
+		dev_err(&hba->pdev->dev,
+			"Task management command timed-out\n");
+		err = FAILED;
+		goto out;
+	}
+	clear_bit(free_slot, &hba->tm_condition);
+	return ufshcd_task_req_compl(hba, free_slot);
+out:
+	return err;
+}
+
+/**
+ * ufshcd_device_reset - reset device and abort all the pending commands
+ * @cmd: SCSI command pointer
+ *
+ * Returns SUCCESS/FAILED
+ */
+static int ufshcd_device_reset(struct scsi_cmnd *cmd)
+{
+	struct Scsi_Host *host;
+	struct ufs_hba *hba;
+	unsigned int tag;
+	u32 pos;
+	int err;
+
+	host = cmd->device->host;
+	hba = shost_priv(host);
+	tag = cmd->request->tag;
+
+	err = ufshcd_issue_tm_cmd(hba, &hba->lrb[tag], UFS_LOGICAL_RESET);
+	if (err)
+		goto out;
+
+	for (pos = 0; pos < hba->nutrs; pos++) {
+		if (test_bit(pos, &hba->outstanding_reqs) &&
+		    (hba->lrb[tag].lun == hba->lrb[pos].lun)) {
+
+			/* clear the respective UTRLCLR register bit */
+			ufshcd_utrl_clear(hba, pos);
+
+			clear_bit(pos, &hba->outstanding_reqs);
+
+			if (hba->lrb[pos].cmd) {
+				scsi_dma_unmap(hba->lrb[pos].cmd);
+				hba->lrb[pos].cmd->result =
+						DID_ABORT << 16;
+				hba->lrb[pos].cmd->scsi_done(cmd);
+				hba->lrb[pos].cmd = NULL;
+			}
+		}
+	} /* end of for */
+out:
+	return err;
+}
+
+/**
+ * ufshcd_host_reset - Main reset function registered with scsi layer
+ * @cmd: SCSI command pointer
+ *
+ * Returns SUCCESS/FAILED
+ */
+static int ufshcd_host_reset(struct scsi_cmnd *cmd)
+{
+	struct ufs_hba *hba;
+
+	hba = shost_priv(cmd->device->host);
+
+	if (hba->ufshcd_state == UFSHCD_STATE_RESET)
+		return SUCCESS;
+
+	return (ufshcd_do_reset(hba) == SUCCESS) ? SUCCESS : FAILED;
+}
+
+/**
+ * ufshcd_abort - abort a specific command
+ * @cmd: SCSI command pointer
+ *
+ * Returns SUCCESS/FAILED
+ */
+static int ufshcd_abort(struct scsi_cmnd *cmd)
+{
+	struct Scsi_Host *host;
+	struct ufs_hba *hba;
+	unsigned long flags;
+	unsigned int tag;
+	int err;
+
+	host = cmd->device->host;
+	hba = shost_priv(host);
+	tag = cmd->request->tag;
+
+	spin_lock_irqsave(host->host_lock, flags);
+
+	/* check if command is still pending */
+	if (!(test_bit(tag, &hba->outstanding_reqs))) {
+		err = FAILED;
+		spin_unlock_irqrestore(host->host_lock, flags);
+		goto out;
+	}
+	spin_unlock_irqrestore(host->host_lock, flags);
+
+	err = ufshcd_issue_tm_cmd(hba, &hba->lrb[tag], UFS_ABORT_TASK);
+	if (err)
+		goto out;
+
+	scsi_dma_unmap(cmd);
+
+	spin_lock_irqsave(host->host_lock, flags);
+
+	/* clear the respective UTRLCLR register bit */
+	ufshcd_utrl_clear(hba, tag);
+
+	__clear_bit(tag, &hba->outstanding_reqs);
+	hba->lrb[tag].cmd = NULL;
+	spin_unlock_irqrestore(host->host_lock, flags);
+out:
+	return err;
+}
+
+static struct scsi_host_template ufshcd_driver_template = {
+	.module			= THIS_MODULE,
+	.name			= UFSHCD,
+	.proc_name		= UFSHCD,
+	.queuecommand		= ufshcd_queuecommand,
+	.slave_alloc		= ufshcd_slave_alloc,
+	.slave_destroy		= ufshcd_slave_destroy,
+	.eh_abort_handler	= ufshcd_abort,
+	.eh_device_reset_handler = ufshcd_device_reset,
+	.eh_host_reset_handler	= ufshcd_host_reset,
+	.this_id		= -1,
+	.sg_tablesize		= SG_ALL,
+	.cmd_per_lun		= UFSHCD_CMD_PER_LUN,
+	.can_queue		= UFSHCD_CAN_QUEUE,
+};
+
+/**
+ * ufshcd_shutdown - main function to put the controller in reset state
+ * @pdev: pointer to PCI device handle
+ */
+static void ufshcd_shutdown(struct pci_dev *pdev)
+{
+	ufshcd_hba_stop((struct ufs_hba *)pci_get_drvdata(pdev));
+}
+
+#ifdef CONFIG_PM
+/**
+ * ufshcd_suspend - suspend power management function
+ * @pdev: pointer to PCI device handle
+ * @state: power state
+ *
+ * Returns -ENOSYS
+ */
+static int ufshcd_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+	/*
+	 * TODO:
+	 * 1. Block SCSI requests from SCSI midlayer
+	 * 2. Change the internal driver state to non operational
+	 * 3. Set UTRLRSR and UTMRLRSR bits to zero
+	 * 4. Wait until outstanding commands are completed
+	 * 5. Set HCE to zero to send the UFS host controller to reset state
+	 */
+
+	return -ENOSYS;
+}
+
+/**
+ * ufshcd_resume - resume power management function
+ * @pdev: pointer to PCI device handle
+ *
+ * Returns -ENOSYS
+ */
+static int ufshcd_resume(struct pci_dev *pdev)
+{
+	/*
+	 * TODO:
+	 * 1. Set HCE to 1, to start the UFS host controller
+	 * initialization process
+	 * 2. Set UTRLRSR and UTMRLRSR bits to 1
+	 * 3. Change the internal driver state to operational
+	 * 4. Unblock SCSI requests from SCSI midlayer
+	 */
+
+	return -ENOSYS;
+}
+#endif /* CONFIG_PM */
+
+/**
+ * ufshcd_hba_free - free allocated memory for
+ *			host memory space data structures
+ * @hba: per adapter instance
+ */
+static void ufshcd_hba_free(struct ufs_hba *hba)
+{
+	iounmap(hba->mmio_base);
+	ufshcd_free_hba_memory(hba);
+	pci_release_regions(hba->pdev);
+}
+
+/**
+ * ufshcd_remove - de-allocate PCI/SCSI host and host memory space
+ *		data structure memory
+ * @pdev - pointer to PCI handle
+ */
+static void ufshcd_remove(struct pci_dev *pdev)
+{
+	struct ufs_hba *hba = pci_get_drvdata(pdev);
+
+	/* disable interrupts */
+	ufshcd_int_config(hba, UFSHCD_INT_DISABLE);
+	free_irq(pdev->irq, hba);
+
+	ufshcd_hba_stop(hba);
+	ufshcd_hba_free(hba);
+
+	scsi_remove_host(hba->host);
+	scsi_host_put(hba->host);
+	pci_set_drvdata(pdev, NULL);
+	pci_clear_master(pdev);
+	pci_disable_device(pdev);
+}
+
+/**
+ * ufshcd_set_dma_mask - Set dma mask based on the controller
+ *			 addressing capability
+ * @pdev: PCI device structure
+ *
+ * Returns 0 for success, non-zero for failure
+ */
+static int ufshcd_set_dma_mask(struct ufs_hba *hba)
+{
+	int err;
+	u64 dma_mask;
+
+	/*
+	 * If controller supports 64 bit addressing mode, then set the DMA
+	 * mask to 64-bit, else set the DMA mask to 32-bit
+	 */
+	if (hba->capabilities & MASK_64_ADDRESSING_SUPPORT)
+		dma_mask = DMA_BIT_MASK(64);
+	else
+		dma_mask = DMA_BIT_MASK(32);
+
+	err = pci_set_dma_mask(hba->pdev, dma_mask);
+	if (err)
+		return err;
+
+	err = pci_set_consistent_dma_mask(hba->pdev, dma_mask);
+
+	return err;
+}
+
+/**
+ * ufshcd_probe - probe routine of the driver
+ * @pdev: pointer to PCI device handle
+ * @id: PCI device id
+ *
+ * Returns 0 on success, non-zero value on failure
+ */
+static int __devinit
+ufshcd_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct Scsi_Host *host;
+	struct ufs_hba *hba;
+	int err;
+
+	err = pci_enable_device(pdev);
+	if (err) {
+		dev_err(&pdev->dev, "pci_enable_device failed\n");
+		goto out_error;
+	}
+
+	pci_set_master(pdev);
+
+	host = scsi_host_alloc(&ufshcd_driver_template,
+				sizeof(struct ufs_hba));
+	if (!host) {
+		dev_err(&pdev->dev, "scsi_host_alloc failed\n");
+		err = -ENOMEM;
+		goto out_disable;
+	}
+	hba = shost_priv(host);
+
+	err = pci_request_regions(pdev, UFSHCD);
+	if (err < 0) {
+		dev_err(&pdev->dev, "request regions failed\n");
+		goto out_disable;
+	}
+
+	hba->mmio_base = pci_ioremap_bar(pdev, 0);
+	if (!hba->mmio_base) {
+		dev_err(&pdev->dev, "memory map failed\n");
+		err = -ENOMEM;
+		goto out_release_regions;
+	}
+
+	hba->host = host;
+	hba->pdev = pdev;
+
+	/* Read capabilities registers */
+	ufshcd_hba_capabilities(hba);
+
+	/* Get UFS version supported by the controller */
+	hba->ufs_version = ufshcd_get_ufs_version(hba);
+
+	err = ufshcd_set_dma_mask(hba);
+	if (err) {
+		dev_err(&pdev->dev, "set dma mask failed\n");
+		goto out_iounmap;
+	}
+
+	/* Allocate memory for host memory space */
+	err = ufshcd_memory_alloc(hba);
+	if (err) {
+		dev_err(&pdev->dev, "Memory allocation failed\n");
+		goto out_iounmap;
+	}
+
+	/* Configure LRB */
+	ufshcd_host_memory_configure(hba);
+
+	host->can_queue = hba->nutrs;
+	host->cmd_per_lun = hba->nutrs;
+	host->max_id = UFSHCD_MAX_ID;
+	host->max_lun = UFSHCD_MAX_LUNS;
+	host->max_channel = UFSHCD_MAX_CHANNEL;
+	host->unique_id = host->host_no;
+	host->max_cmd_len = MAX_CDB_SIZE;
+
+	/* Initailize wait queue for task management */
+	init_waitqueue_head(&hba->ufshcd_tm_wait_queue);
+
+	/* Initialize work queues */
+	INIT_WORK(&hba->uic_workq, ufshcd_uic_cc_handler);
+	INIT_WORK(&hba->feh_workq, ufshcd_fatal_err_handler);
+
+	/* IRQ registration */
+	err = request_irq(pdev->irq, ufshcd_intr, IRQF_SHARED, UFSHCD, hba);
+	if (err) {
+		dev_err(&pdev->dev, "request irq failed\n");
+		goto out_lrb_free;
+	}
+
+	/* Enable SCSI tag mapping */
+	err = scsi_init_shared_tag_map(host, host->can_queue);
+	if (err) {
+		dev_err(&pdev->dev, "init shared queue failed\n");
+		goto out_free_irq;
+	}
+
+	pci_set_drvdata(pdev, hba);
+
+	err = scsi_add_host(host, &pdev->dev);
+	if (err) {
+		dev_err(&pdev->dev, "scsi_add_host failed\n");
+		goto out_free_irq;
+	}
+
+	/* Initialization routine */
+	err = ufshcd_initialize_hba(hba);
+	if (err) {
+		dev_err(&pdev->dev, "Initialization failed\n");
+		goto out_free_irq;
+	}
+
+	return 0;
+
+out_free_irq:
+	free_irq(pdev->irq, hba);
+out_lrb_free:
+	ufshcd_free_hba_memory(hba);
+out_iounmap:
+	iounmap(hba->mmio_base);
+out_release_regions:
+	pci_release_regions(pdev);
+out_disable:
+	scsi_host_put(host);
+	pci_clear_master(pdev);
+	pci_disable_device(pdev);
+out_error:
+	return err;
+}
+
+static DEFINE_PCI_DEVICE_TABLE(ufshcd_pci_tbl) = {
+	{ PCI_VENDOR_ID_SAMSUNG, 0xC00C, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
+	{ }	/* terminate list */
+};
+
+MODULE_DEVICE_TABLE(pci, ufshcd_pci_tbl);
+
+static struct pci_driver ufshcd_pci_driver = {
+	.name = UFSHCD,
+	.id_table = ufshcd_pci_tbl,
+	.probe = ufshcd_probe,
+	.remove = __devexit_p(ufshcd_remove),
+	.shutdown = ufshcd_shutdown,
+#ifdef CONFIG_PM
+	.suspend = ufshcd_suspend,
+	.resume = ufshcd_resume,
+#endif
+};
+
+/**
+ * ufshcd_init - Driver registration routine
+ */
+static int __init ufshcd_init(void)
+{
+	return pci_register_driver(&ufshcd_pci_driver);
+}
+module_init(ufshcd_init);
+
+/**
+ * ufshcd_exit - Driver exit clean-up routine
+ */
+static void __exit ufshcd_exit(void)
+{
+	pci_unregister_driver(&ufshcd_pci_driver);
+}
+module_exit(ufshcd_exit);
+
+
+MODULE_AUTHOR("Santosh Yaragnavi <santosh.sy@samsung.com>, "
+	      "Vinayak Holikatti <h.vinayak@samsung.com>");
+MODULE_DESCRIPTION("Generic UFS host controller driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(UFSHCD_DRIVER_VERSION);