/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * SAS host prototypes and structures header file
 *
 * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
 * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
 */

#ifndef _LIBSAS_H_
#define _LIBSAS_H_


#include <linux/timer.h>
#include <linux/pci.h>
#include <scsi/sas.h>
#include <linux/libata.h>
#include <linux/list.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_transport_sas.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>

struct block_device;

enum sas_phy_role {
	PHY_ROLE_NONE = 0,
	PHY_ROLE_TARGET = 0x40,
	PHY_ROLE_INITIATOR = 0x80,
};

/* The events are mnemonically described in sas_dump.c
 * so when updating/adding events here, please also
 * update the other file too.
 */
enum port_event {
	PORTE_BYTES_DMAED     = 0U,
	PORTE_BROADCAST_RCVD,
	PORTE_LINK_RESET_ERR,
	PORTE_TIMER_EVENT,
	PORTE_HARD_RESET,
	PORT_NUM_EVENTS,
};

enum phy_event {
	PHYE_LOSS_OF_SIGNAL   = 0U,
	PHYE_OOB_DONE,
	PHYE_OOB_ERROR,
	PHYE_SPINUP_HOLD,             /* hot plug SATA, no COMWAKE sent */
	PHYE_RESUME_TIMEOUT,
	PHYE_SHUTDOWN,
	PHY_NUM_EVENTS,
};

enum discover_event {
	DISCE_DISCOVER_DOMAIN   = 0U,
	DISCE_REVALIDATE_DOMAIN,
	DISCE_SUSPEND,
	DISCE_RESUME,
	DISC_NUM_EVENTS,
};

/* ---------- Expander Devices ---------- */

enum routing_attribute {
	DIRECT_ROUTING,
	SUBTRACTIVE_ROUTING,
	TABLE_ROUTING,
};

enum ex_phy_state {
	PHY_EMPTY,
	PHY_VACANT,
	PHY_NOT_PRESENT,
	PHY_DEVICE_DISCOVERED
};

struct ex_phy {
	int    phy_id;

	enum ex_phy_state phy_state;

	enum sas_device_type attached_dev_type;
	enum sas_linkrate linkrate;

	u8   attached_sata_host:1;
	u8   attached_sata_dev:1;
	u8   attached_sata_ps:1;

	enum sas_protocol attached_tproto;
	enum sas_protocol attached_iproto;

	u8   attached_sas_addr[SAS_ADDR_SIZE];
	u8   attached_phy_id;

	int phy_change_count;
	enum routing_attribute routing_attr;
	u8   virtual:1;

	int  last_da_index;

	struct sas_phy *phy;
	struct sas_port *port;
};

struct expander_device {
	struct list_head children;

	int    ex_change_count;
	u16    max_route_indexes;
	u8     num_phys;

	u8     t2t_supp:1;
	u8     configuring:1;
	u8     conf_route_table:1;

	u8     enclosure_logical_id[8];

	struct ex_phy *ex_phy;
	struct sas_port *parent_port;

	struct mutex cmd_mutex;
};

/* ---------- SATA device ---------- */
#define ATA_RESP_FIS_SIZE 24

struct sata_device {
	unsigned int class;
	u8     port_no;        /* port number, if this is a PM (Port) */

	struct ata_port *ap;
	struct ata_host *ata_host;
	struct smp_rps_resp rps_resp ____cacheline_aligned; /* report_phy_sata_resp */
	u8     fis[ATA_RESP_FIS_SIZE];
};

struct ssp_device {
	struct list_head eh_list_node; /* pending a user requested eh action */
	struct scsi_lun reset_lun;
};

enum {
	SAS_DEV_GONE,
	SAS_DEV_FOUND, /* device notified to lldd */
	SAS_DEV_DESTROY,
	SAS_DEV_EH_PENDING,
	SAS_DEV_LU_RESET,
	SAS_DEV_RESET,
};

struct domain_device {
	spinlock_t done_lock;
	enum sas_device_type dev_type;

	enum sas_linkrate linkrate;
	enum sas_linkrate min_linkrate;
	enum sas_linkrate max_linkrate;

	int  pathways;

	struct domain_device *parent;
	struct list_head siblings; /* devices on the same level */
	struct asd_sas_port *port;        /* shortcut to root of the tree */
	struct sas_phy *phy;

	struct list_head dev_list_node;
	struct list_head disco_list_node; /* awaiting probe or destruct */

	enum sas_protocol    iproto;
	enum sas_protocol    tproto;

	struct sas_rphy *rphy;

	u8  sas_addr[SAS_ADDR_SIZE];
	u8  hashed_sas_addr[HASHED_SAS_ADDR_SIZE];

	u8  frame_rcvd[32];

	union {
		struct expander_device ex_dev;
		struct sata_device     sata_dev; /* STP & directly attached */
		struct ssp_device      ssp_dev;
	};

	void *lldd_dev;
	unsigned long state;
	struct kref kref;
};

struct sas_work {
	struct list_head drain_node;
	struct work_struct work;
};

static inline bool dev_is_expander(enum sas_device_type type)
{
	return type == SAS_EDGE_EXPANDER_DEVICE ||
	       type == SAS_FANOUT_EXPANDER_DEVICE;
}

static inline bool dev_parent_is_expander(struct domain_device *dev)
{
	if (!dev->parent)
		return false;

	return dev_is_expander(dev->parent->dev_type);
}

static inline void INIT_SAS_WORK(struct sas_work *sw, void (*fn)(struct work_struct *))
{
	INIT_WORK(&sw->work, fn);
	INIT_LIST_HEAD(&sw->drain_node);
}

struct sas_discovery_event {
	struct sas_work work;
	struct asd_sas_port *port;
};

static inline struct sas_discovery_event *to_sas_discovery_event(struct work_struct *work)
{
	struct sas_discovery_event *ev = container_of(work, typeof(*ev), work.work);

	return ev;
}

struct sas_discovery {
	struct sas_discovery_event disc_work[DISC_NUM_EVENTS];
	unsigned long    pending;
	u8     fanout_sas_addr[SAS_ADDR_SIZE];
	u8     eeds_a[SAS_ADDR_SIZE];
	u8     eeds_b[SAS_ADDR_SIZE];
	int    max_level;
};

/* The port struct is Class:RW, driver:RO */
struct asd_sas_port {
/* private: */
	struct sas_discovery disc;
	struct domain_device *port_dev;
	spinlock_t dev_list_lock;
	struct list_head dev_list;
	struct list_head disco_list;
	struct list_head destroy_list;
	struct list_head sas_port_del_list;
	enum   sas_linkrate linkrate;

	struct sas_work work;
	int suspended;

/* public: */
	int id;

	u8               sas_addr[SAS_ADDR_SIZE];
	u8               attached_sas_addr[SAS_ADDR_SIZE];
	enum sas_protocol   iproto;
	enum sas_protocol   tproto;

	enum sas_oob_mode oob_mode;

	spinlock_t       phy_list_lock;
	struct list_head phy_list;
	int              num_phys;
	u32              phy_mask;

	struct sas_ha_struct *ha;

	struct sas_port	*port;

	void *lldd_port;	  /* not touched by the sas class code */
};

struct asd_sas_event {
	struct sas_work work;
	struct asd_sas_phy *phy;
	int event;
};

static inline struct asd_sas_event *to_asd_sas_event(struct work_struct *work)
{
	struct asd_sas_event *ev = container_of(work, typeof(*ev), work.work);

	return ev;
}

static inline void INIT_SAS_EVENT(struct asd_sas_event *ev,
		void (*fn)(struct work_struct *),
		struct asd_sas_phy *phy, int event)
{
	INIT_SAS_WORK(&ev->work, fn);
	ev->phy = phy;
	ev->event = event;
}

#define SAS_PHY_SHUTDOWN_THRES   1024

/* The phy pretty much is controlled by the LLDD.
 * The class only reads those fields.
 */
struct asd_sas_phy {
/* private: */
	atomic_t event_nr;
	int in_shutdown;
	int error;
	int suspended;

	struct sas_phy *phy;

/* public: */
	/* The following are class:RO, driver:R/W */
	int            enabled;	  /* must be set */

	int            id;	  /* must be set */
	enum sas_protocol iproto;
	enum sas_protocol tproto;

	enum sas_phy_role  role;
	enum sas_oob_mode  oob_mode;
	enum sas_linkrate linkrate;

	u8   *sas_addr;		  /* must be set */
	u8   attached_sas_addr[SAS_ADDR_SIZE]; /* class:RO, driver: R/W */

	spinlock_t     frame_rcvd_lock;
	u8             *frame_rcvd; /* must be set */
	int            frame_rcvd_size;

	spinlock_t     sas_prim_lock;
	u32            sas_prim;

	struct list_head port_phy_el; /* driver:RO */
	struct asd_sas_port      *port; /* Class:RW, driver: RO */

	struct sas_ha_struct *ha; /* may be set; the class sets it anyway */

	void *lldd_phy;		  /* not touched by the sas_class_code */
};

enum sas_ha_state {
	SAS_HA_REGISTERED,
	SAS_HA_DRAINING,
	SAS_HA_ATA_EH_ACTIVE,
	SAS_HA_FROZEN,
	SAS_HA_RESUMING,
};

struct sas_ha_struct {
/* private: */
	struct list_head  defer_q; /* work queued while draining */
	struct mutex	  drain_mutex;
	unsigned long	  state;
	spinlock_t	  lock;
	int		  eh_active;
	wait_queue_head_t eh_wait_q;
	struct list_head  eh_dev_q;

	struct mutex disco_mutex;

	struct Scsi_Host *shost;

/* public: */
	char *sas_ha_name;
	struct device *dev;	  /* should be set */

	struct workqueue_struct *event_q;
	struct workqueue_struct *disco_q;

	u8 *sas_addr;		  /* must be set */
	u8 hashed_sas_addr[HASHED_SAS_ADDR_SIZE];

	spinlock_t      phy_port_lock;
	struct asd_sas_phy  **sas_phy; /* array of valid pointers, must be set */
	struct asd_sas_port **sas_port; /* array of valid pointers, must be set */
	int             num_phys; /* must be set, gt 0, static */

	int strict_wide_ports; /* both sas_addr and attached_sas_addr must match
				* their siblings when forming wide ports */

	void *lldd_ha;		  /* not touched by sas class code */

	struct list_head eh_done_q;  /* complete via scsi_eh_flush_done_q */
	struct list_head eh_ata_q; /* scmds to promote from sas to ata eh */

	int event_thres;
};

#define SHOST_TO_SAS_HA(_shost) (*(struct sas_ha_struct **)(_shost)->hostdata)

static inline struct domain_device *
starget_to_domain_dev(struct scsi_target *starget) {
	return starget->hostdata;
}

static inline struct domain_device *
sdev_to_domain_dev(struct scsi_device *sdev) {
	return starget_to_domain_dev(sdev->sdev_target);
}

static inline struct ata_device *sas_to_ata_dev(struct domain_device *dev)
{
	return &dev->sata_dev.ap->link.device[0];
}

static inline struct domain_device *
cmd_to_domain_dev(struct scsi_cmnd *cmd)
{
	return sdev_to_domain_dev(cmd->device);
}

/* Before calling a notify event, LLDD should use this function
 * when the link is severed (possibly from its tasklet).
 * The idea is that the Class only reads those, while the LLDD,
 * can R/W these (thus avoiding a race).
 */
static inline void sas_phy_disconnected(struct asd_sas_phy *phy)
{
	phy->oob_mode = OOB_NOT_CONNECTED;
	phy->linkrate = SAS_LINK_RATE_UNKNOWN;
}

static inline unsigned int to_sas_gpio_od(int device, int bit)
{
	return 3 * device + bit;
}

static inline void sas_put_local_phy(struct sas_phy *phy)
{
	put_device(&phy->dev);
}

#ifdef CONFIG_SCSI_SAS_HOST_SMP
int try_test_sas_gpio_gp_bit(unsigned int od, u8 *data, u8 index, u8 count);
#else
static inline int try_test_sas_gpio_gp_bit(unsigned int od, u8 *data, u8 index, u8 count)
{
	return -1;
}
#endif

/* ---------- Tasks ---------- */
/*
      service_response |  SAS_TASK_COMPLETE  |  SAS_TASK_UNDELIVERED |
  exec_status          |                     |                       |
  ---------------------+---------------------+-----------------------+
       SAM_...         |         X           |                       |
       DEV_NO_RESPONSE |         X           |           X           |
       INTERRUPTED     |         X           |                       |
       QUEUE_FULL      |                     |           X           |
       DEVICE_UNKNOWN  |                     |           X           |
       SG_ERR          |                     |           X           |
  ---------------------+---------------------+-----------------------+
 */

enum service_response {
	SAS_TASK_COMPLETE,
	SAS_TASK_UNDELIVERED = -1,
};

enum exec_status {
	/*
	 * Values 0..0x7f are used to return the SAM_STAT_* codes.  To avoid
	 * 'case value not in enumerated type' compiler warnings every value
	 * returned through the exec_status enum needs an alias with the SAS_
	 * prefix here.
	 */
	SAS_SAM_STAT_GOOD = SAM_STAT_GOOD,
	SAS_SAM_STAT_BUSY = SAM_STAT_BUSY,
	SAS_SAM_STAT_TASK_ABORTED = SAM_STAT_TASK_ABORTED,
	SAS_SAM_STAT_CHECK_CONDITION = SAM_STAT_CHECK_CONDITION,

	SAS_DEV_NO_RESPONSE = 0x80,
	SAS_DATA_UNDERRUN,
	SAS_DATA_OVERRUN,
	SAS_INTERRUPTED,
	SAS_QUEUE_FULL,
	SAS_DEVICE_UNKNOWN,
	SAS_OPEN_REJECT,
	SAS_OPEN_TO,
	SAS_PROTO_RESPONSE,
	SAS_PHY_DOWN,
	SAS_NAK_R_ERR,
	SAS_PENDING,
	SAS_ABORTED_TASK,
};

/* When a task finishes with a response, the LLDD examines the
 * response:
 *	- For an ATA task task_status_struct::stat is set to
 * SAS_PROTO_RESPONSE, and the task_status_struct::buf is set to the
 * contents of struct ata_task_resp.
 *	- For SSP tasks, if no data is present or status/TMF response
 * is valid, task_status_struct::stat is set.  If data is present
 * (SENSE data), the LLDD copies up to SAS_STATUS_BUF_SIZE, sets
 * task_status_struct::buf_valid_size, and task_status_struct::stat is
 * set to SAM_CHECK_COND.
 *
 * "buf" has format SCSI Sense for SSP task, or struct ata_task_resp
 * for ATA task.
 *
 * "frame_len" is the total frame length, which could be more or less
 * than actually copied.
 *
 * Tasks ending with response, always set the residual field.
 */
struct ata_task_resp {
	u16  frame_len;
	u8   ending_fis[ATA_RESP_FIS_SIZE];	  /* dev to host or data-in */
};

#define SAS_STATUS_BUF_SIZE 96

struct task_status_struct {
	enum service_response resp;
	enum exec_status      stat;
	int  buf_valid_size;

	u8   buf[SAS_STATUS_BUF_SIZE];

	u32  residual;
	enum sas_open_rej_reason open_rej_reason;
};

/* ATA and ATAPI task queuable to a SAS LLDD.
 */
struct sas_ata_task {
	struct host_to_dev_fis fis;
	u8     atapi_packet[16];  /* 0 if not ATAPI task */

	u8     dma_xfer:1;	  /* PIO:0 or DMA:1 */
	u8     use_ncq:1;
	u8     return_fis_on_success:1;

	u8     device_control_reg_update:1;

	bool   force_phy;
	int    force_phy_id;
};

/* LLDDs rely on these values */
enum sas_internal_abort {
	SAS_INTERNAL_ABORT_SINGLE	= 0,
	SAS_INTERNAL_ABORT_DEV		= 1,
};

struct sas_internal_abort_task {
	enum sas_internal_abort type;
	unsigned int qid;
	u16 tag;
};

struct sas_smp_task {
	struct scatterlist smp_req;
	struct scatterlist smp_resp;
};

enum task_attribute {
	TASK_ATTR_SIMPLE = 0,
	TASK_ATTR_HOQ    = 1,
	TASK_ATTR_ORDERED= 2,
	TASK_ATTR_ACA    = 4,
};

struct sas_ssp_task {
	u8     LUN[8];
	enum   task_attribute task_attr;
	struct scsi_cmnd *cmd;
};

struct sas_tmf_task {
	u8 tmf;
	u16 tag_of_task_to_be_managed;
};

struct sas_task {
	struct domain_device *dev;

	spinlock_t   task_state_lock;
	unsigned     task_state_flags;

	enum   sas_protocol      task_proto;

	union {
		struct sas_ata_task ata_task;
		struct sas_smp_task smp_task;
		struct sas_ssp_task ssp_task;
		struct sas_internal_abort_task abort_task;
	};

	struct scatterlist *scatter;
	int    num_scatter;
	u32    total_xfer_len;
	u8     data_dir:2;	  /* Use PCI_DMA_... */

	struct task_status_struct task_status;
	void   (*task_done)(struct sas_task *);

	void   *lldd_task;	  /* for use by LLDDs */
	void   *uldd_task;
	struct sas_task_slow *slow_task;
	struct sas_tmf_task *tmf;
};

struct sas_task_slow {
	/* standard/extra infrastructure for slow path commands (SMP and
	 * internal lldd commands
	 */
	struct timer_list     timer;
	struct completion     completion;
	struct sas_task       *task;
};

#define SAS_TASK_STATE_PENDING      1
#define SAS_TASK_STATE_DONE         2
#define SAS_TASK_STATE_ABORTED      4
#define SAS_TASK_NEED_DEV_RESET     8

static inline bool sas_is_internal_abort(struct sas_task *task)
{
	return task->task_proto == SAS_PROTOCOL_INTERNAL_ABORT;
}

static inline struct request *sas_task_find_rq(struct sas_task *task)
{
	struct scsi_cmnd *scmd;

	if (task->task_proto & SAS_PROTOCOL_STP_ALL) {
		struct ata_queued_cmd *qc = task->uldd_task;

		scmd = qc ? qc->scsicmd : NULL;
	} else {
		scmd = task->uldd_task;
	}

	if (!scmd)
		return NULL;

	return scsi_cmd_to_rq(scmd);
}

struct sas_domain_function_template {
	/* The class calls these to notify the LLDD of an event. */
	void (*lldd_port_formed)(struct asd_sas_phy *);
	void (*lldd_port_deformed)(struct asd_sas_phy *);

	/* The class calls these when a device is found or gone. */
	int  (*lldd_dev_found)(struct domain_device *);
	void (*lldd_dev_gone)(struct domain_device *);

	int (*lldd_execute_task)(struct sas_task *, gfp_t gfp_flags);

	/* Task Management Functions. Must be called from process context. */
	int (*lldd_abort_task)(struct sas_task *);
	int (*lldd_abort_task_set)(struct domain_device *, u8 *lun);
	int (*lldd_clear_task_set)(struct domain_device *, u8 *lun);
	int (*lldd_I_T_nexus_reset)(struct domain_device *);
	int (*lldd_ata_check_ready)(struct domain_device *);
	void (*lldd_ata_set_dmamode)(struct domain_device *);
	int (*lldd_lu_reset)(struct domain_device *, u8 *lun);
	int (*lldd_query_task)(struct sas_task *);

	/* Special TMF callbacks */
	void (*lldd_tmf_exec_complete)(struct domain_device *dev);
	void (*lldd_tmf_aborted)(struct sas_task *task);
	bool (*lldd_abort_timeout)(struct sas_task *task, void *data);

	/* Port and Adapter management */
	int (*lldd_clear_nexus_port)(struct asd_sas_port *);
	int (*lldd_clear_nexus_ha)(struct sas_ha_struct *);

	/* Phy management */
	int (*lldd_control_phy)(struct asd_sas_phy *, enum phy_func, void *);

	/* GPIO support */
	int (*lldd_write_gpio)(struct sas_ha_struct *, u8 reg_type,
			       u8 reg_index, u8 reg_count, u8 *write_data);
};

extern int sas_register_ha(struct sas_ha_struct *);
extern int sas_unregister_ha(struct sas_ha_struct *);
extern void sas_prep_resume_ha(struct sas_ha_struct *sas_ha);
extern void sas_resume_ha(struct sas_ha_struct *sas_ha);
extern void sas_resume_ha_no_sync(struct sas_ha_struct *sas_ha);
extern void sas_suspend_ha(struct sas_ha_struct *sas_ha);

int sas_phy_reset(struct sas_phy *phy, int hard_reset);
int sas_phy_enable(struct sas_phy *phy, int enable);
extern enum scsi_qc_status sas_queuecommand(struct Scsi_Host *host,
					    struct scsi_cmnd *cmd);
extern int sas_target_alloc(struct scsi_target *);
int sas_sdev_configure(struct scsi_device *dev, struct queue_limits *lim);
extern int sas_change_queue_depth(struct scsi_device *, int new_depth);
extern int sas_bios_param(struct scsi_device *, struct gendisk *,
			  sector_t capacity, int *hsc);
int sas_execute_internal_abort_single(struct domain_device *device,
				      u16 tag, unsigned int qid,
				      void *data);
int sas_execute_internal_abort_dev(struct domain_device *device,
				   unsigned int qid, void *data);
extern struct scsi_transport_template *
sas_domain_attach_transport(struct sas_domain_function_template *);
extern struct device_attribute dev_attr_phy_event_threshold;

void sas_task_abort(struct sas_task *);
int sas_eh_abort_handler(struct scsi_cmnd *cmd);
int sas_eh_device_reset_handler(struct scsi_cmnd *cmd);
int sas_eh_target_reset_handler(struct scsi_cmnd *cmd);

extern void sas_target_destroy(struct scsi_target *);
extern int sas_sdev_init(struct scsi_device *);
extern int sas_ioctl(struct scsi_device *sdev, unsigned int cmd,
		     void __user *arg);
extern int sas_drain_work(struct sas_ha_struct *ha);

extern void sas_ssp_task_response(struct device *dev, struct sas_task *task,
				  struct ssp_response_iu *iu);
struct sas_phy *sas_get_local_phy(struct domain_device *dev);

int sas_request_addr(struct Scsi_Host *shost, u8 *addr);

int sas_abort_task_set(struct domain_device *dev, u8 *lun);
int sas_clear_task_set(struct domain_device *dev, u8 *lun);
int sas_lu_reset(struct domain_device *dev, u8 *lun);
int sas_query_task(struct sas_task *task, u16 tag);
int sas_abort_task(struct sas_task *task, u16 tag);
int sas_find_attached_phy_id(struct expander_device *ex_dev,
			     struct domain_device *dev);

void sas_notify_port_event(struct asd_sas_phy *phy, enum port_event event,
			   gfp_t gfp_flags);
void sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event,
			   gfp_t gfp_flags);

#define __LIBSAS_SHT_BASE						\
	.module				= THIS_MODULE,			\
	.name				= DRV_NAME,			\
	.proc_name			= DRV_NAME,			\
	.queuecommand			= sas_queuecommand,		\
	.dma_need_drain			= ata_scsi_dma_need_drain,	\
	.target_alloc			= sas_target_alloc,		\
	.change_queue_depth		= sas_change_queue_depth,	\
	.bios_param			= sas_bios_param,		\
	.this_id			= -1,				\
	.eh_device_reset_handler	= sas_eh_device_reset_handler,	\
	.eh_target_reset_handler	= sas_eh_target_reset_handler,	\
	.target_destroy			= sas_target_destroy,		\
	.ioctl				= sas_ioctl,			\

#ifdef CONFIG_COMPAT
#define _LIBSAS_SHT_BASE		__LIBSAS_SHT_BASE		\
	.compat_ioctl			= sas_ioctl,
#else
#define _LIBSAS_SHT_BASE		__LIBSAS_SHT_BASE
#endif

#define LIBSAS_SHT_BASE			_LIBSAS_SHT_BASE		\
	.sdev_configure			= sas_sdev_configure,		\
	.sdev_init			= sas_sdev_init,		\

#define LIBSAS_SHT_BASE_NO_SLAVE_INIT	_LIBSAS_SHT_BASE


#endif /* _SASLIB_H_ */