/*
 * Universal Flash Storage Host controller driver
 *
 * This code is based on drivers/scsi/ufs/ufshcd.h
 * Copyright (C) 2011-2013 Samsung India Software Operations
 *
 * Authors:
 *	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.
 * See the COPYING file in the top-level directory or visit
 * <http://www.gnu.org/licenses/gpl-2.0.html>
 *
 * 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.
 *
 * This program is provided "AS IS" and "WITH ALL FAULTS" and
 * without warranty of any kind. You are solely responsible for
 * determining the appropriateness of using and distributing
 * the program and assume all risks associated with your exercise
 * of rights with respect to the program, including but not limited
 * to infringement of third party rights, the risks and costs of
 * program errors, damage to or loss of data, programs or equipment,
 * and unavailability or interruption of operations. Under no
 * circumstances will the contributor of this Program be liable for
 * any damages of any kind arising from your use or distribution of
 * this program.
 */

#ifndef _UFSHCD_H
#define _UFSHCD_H

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.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 <linux/pm_runtime.h>
#include <linux/clk.h>
#include <linux/completion.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 "0.2"

enum dev_cmd_type {
	DEV_CMD_TYPE_NOP		= 0x0,
	DEV_CMD_TYPE_QUERY		= 0x1,
};

/**
 * 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
 * @done: UIC command completion
 */
struct uic_command {
	u32 command;
	u32 argument1;
	u32 argument2;
	u32 argument3;
	int cmd_active;
	int result;
	struct completion done;
};

/**
 * struct ufshcd_lrb - local reference block
 * @utr_descriptor_ptr: UTRD 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
 * @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
 * @intr_cmd: Interrupt command (doesn't participate in interrupt aggregation)
 */
struct ufshcd_lrb {
	struct utp_transfer_req_desc *utr_descriptor_ptr;
	struct utp_upiu_req *ucd_req_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;
	bool intr_cmd;
};

/**
 * struct ufs_query - holds relevent data structures for query request
 * @request: request upiu and function
 * @descriptor: buffer for sending/receiving descriptor
 * @response: response upiu and response
 */
struct ufs_query {
	struct ufs_query_req request;
	u8 *descriptor;
	struct ufs_query_res response;
};

/**
 * struct ufs_dev_cmd - all assosiated fields with device management commands
 * @type: device management command type - Query, NOP OUT
 * @lock: lock to allow one command at a time
 * @complete: internal commands completion
 * @tag_wq: wait queue until free command slot is available
 */
struct ufs_dev_cmd {
	enum dev_cmd_type type;
	struct mutex lock;
	struct completion *complete;
	wait_queue_head_t tag_wq;
	struct ufs_query query;
};

/**
 * 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
 * @dev: device handle
 * @lrb: local reference block
 * @lrb_in_use: lrb in use
 * @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
 * @ufs_version: UFS Version to which controller complies
 * @irq: Irq number of the controller
 * @active_uic_cmd: handle of active UIC command
 * @uic_cmd_mutex: mutex for uic command
 * @ufshcd_tm_wait_queue: wait queue for task management
 * @tm_condition: condition variable for task management
 * @ufshcd_state: UFSHCD states
 * @intr_mask: Interrupt Mask Bits
 * @ee_ctrl_mask: Exception event control mask
 * @feh_workq: Work queue for fatal controller error handling
 * @eeh_work: Worker to handle exception events
 * @errors: HBA errors
 * @dev_cmd: ufs device management command information
 * @auto_bkops_enabled: to track whether bkops is enabled in device
 */
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 device *dev;

	struct ufshcd_lrb *lrb;
	unsigned long lrb_in_use;

	unsigned long outstanding_tasks;
	unsigned long outstanding_reqs;

	u32 capabilities;
	int nutrs;
	int nutmrs;
	u32 ufs_version;
	unsigned int irq;

	struct uic_command *active_uic_cmd;
	struct mutex uic_cmd_mutex;

	wait_queue_head_t ufshcd_tm_wait_queue;
	unsigned long tm_condition;

	u32 ufshcd_state;
	u32 intr_mask;
	u16 ee_ctrl_mask;

	/* Work Queues */
	struct work_struct feh_workq;
	struct work_struct eeh_work;

	/* HBA Errors */
	u32 errors;

	/* Device management request data */
	struct ufs_dev_cmd dev_cmd;

	bool auto_bkops_enabled;
};

#define ufshcd_writel(hba, val, reg)	\
	writel((val), (hba)->mmio_base + (reg))
#define ufshcd_readl(hba, reg)	\
	readl((hba)->mmio_base + (reg))

int ufshcd_init(struct device *, struct ufs_hba ** , void __iomem * ,
			unsigned int);
void ufshcd_remove(struct ufs_hba *);

/**
 * ufshcd_hba_stop - Send controller to reset state
 * @hba: per adapter instance
 */
static inline void ufshcd_hba_stop(struct ufs_hba *hba)
{
	ufshcd_writel(hba, CONTROLLER_DISABLE,  REG_CONTROLLER_ENABLE);
}

static inline void check_upiu_size(void)
{
	BUILD_BUG_ON(ALIGNED_UPIU_SIZE <
		GENERAL_UPIU_REQUEST_SIZE + QUERY_DESC_MAX_SIZE);
}

extern int ufshcd_runtime_suspend(struct ufs_hba *hba);
extern int ufshcd_runtime_resume(struct ufs_hba *hba);
extern int ufshcd_runtime_idle(struct ufs_hba *hba);
#endif /* End of Header */