/* 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_class {
        SAS,
        EXPANDER
};

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

enum sas_phy_type {
        PHY_TYPE_PHYSICAL,
        PHY_TYPE_VIRTUAL
};

/* 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 ---------- */

#define to_dom_device(_obj) container_of(_obj, struct domain_device, dev_obj)
#define to_dev_attr(_attr)  container_of(_attr, struct domain_dev_attribute,\
                                         attr)

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_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 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;

        enum sas_class   class;
        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_class class;
        enum sas_protocol iproto;
        enum sas_protocol tproto;

        enum sas_phy_type  type;
        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 */
};

struct scsi_core {
        struct Scsi_Host *shost;

};

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

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_core core;

/* public: */
        char *sas_ha_name;
        struct device *dev;       /* should be set */
        struct module *lldd_module; /* 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);
}

void sas_hash_addr(u8 *hashed, const u8 *sas_addr);

/* 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_SG_ERR,
        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     retry_count;       /* hardware retry, should be > 0 */

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

        u8     device_control_reg_update:1;
};

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     retry_count;       /* hardware retry, should be > 0 */

        u8     LUN[8];
        u8     enable_first_burst:1;
        enum   task_attribute task_attr;
        u8     task_prio;
        struct scsi_cmnd *cmd;
};

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 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_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
#define SAS_TASK_AT_INITIATOR       16

extern struct sas_task *sas_alloc_task(gfp_t flags);
extern struct sas_task *sas_alloc_slow_task(gfp_t flags);
extern void sas_free_task(struct sas_task *task);

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_aca)(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 *);

        /* 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_suspend_ha(struct sas_ha_struct *sas_ha);

int sas_set_phy_speed(struct sas_phy *phy, struct sas_phy_linkrates *rates);
int sas_phy_reset(struct sas_phy *phy, int hard_reset);
extern int sas_queuecommand(struct Scsi_Host *, struct scsi_cmnd *);
extern int sas_target_alloc(struct scsi_target *);
extern int sas_slave_configure(struct scsi_device *);
extern int sas_change_queue_depth(struct scsi_device *, int new_depth);
extern int sas_bios_param(struct scsi_device *, struct block_device *,
                          sector_t capacity, int *hsc);
extern struct scsi_transport_template *
sas_domain_attach_transport(struct sas_domain_function_template *);
extern struct device_attribute dev_attr_phy_event_threshold;

int  sas_discover_root_expander(struct domain_device *);

void sas_init_ex_attr(void);

int  sas_ex_revalidate_domain(struct domain_device *);

void sas_unregister_domain_devices(struct asd_sas_port *port, int gone);
void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *);
int  sas_discover_event(struct asd_sas_port *, enum discover_event ev);

int  sas_discover_sata(struct domain_device *);
int  sas_discover_end_dev(struct domain_device *);

void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *);

void sas_init_dev(struct domain_device *);

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_slave_alloc(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_notify_port_event(struct asd_sas_phy *phy, enum port_event event,
                          gfp_t gfp_flags);
int sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event,
                         gfp_t gfp_flags);

#endif /* _SASLIB_H_ */