/* SPDX-License-Identifier: GPL-2.0-only */
/* Copyright 2014 Cisco Systems, Inc.  All rights reserved. */

#ifndef _SNIC_H_
#define _SNIC_H_

#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/workqueue.h>
#include <linux/bitops.h>
#include <linux/mempool.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>

#include "snic_disc.h"
#include "snic_io.h"
#include "snic_res.h"
#include "snic_trc.h"
#include "snic_stats.h"
#include "vnic_dev.h"
#include "vnic_wq.h"
#include "vnic_cq.h"
#include "vnic_intr.h"
#include "vnic_stats.h"
#include "vnic_snic.h"

#define SNIC_DRV_NAME           "snic"
#define SNIC_DRV_DESCRIPTION    "Cisco SCSI NIC Driver"
#define SNIC_DRV_VERSION        "0.0.1.18"
#define PFX                     SNIC_DRV_NAME ":"
#define DFX                     SNIC_DRV_NAME "%d: "

#define DESC_CLEAN_LOW_WATERMARK        8
#define SNIC_UCSM_DFLT_THROTTLE_CNT_BLD 16 /* UCSM default throttle count */
#define SNIC_MAX_IO_REQ                 50 /* scsi_cmnd tag map entries */
#define SNIC_MIN_IO_REQ                 8  /* Min IO throttle count */
#define SNIC_IO_LOCKS                   64 /* IO locks: power of 2 */
#define SNIC_DFLT_QUEUE_DEPTH           32 /* Default Queue Depth */
#define SNIC_MAX_QUEUE_DEPTH            64 /* Max Queue Depth */
#define SNIC_DFLT_CMD_TIMEOUT           90 /* Extended tmo for FW */

/*
 * Tag bits used for special requests.
 */
#define SNIC_TAG_ABORT          BIT(30)         /* Tag indicating abort */
#define SNIC_TAG_DEV_RST        BIT(29)         /* Tag for device reset */
#define SNIC_TAG_IOCTL_DEV_RST  BIT(28)         /* Tag for User Device Reset */
#define SNIC_TAG_MASK           (BIT(24) - 1)   /* Mask for lookup */
#define SNIC_NO_TAG             -1

/*
 * Command flags to identify the type of command and for other future use
 */
#define SNIC_NO_FLAGS                   0
#define SNIC_IO_INITIALIZED             BIT(0)
#define SNIC_IO_ISSUED                  BIT(1)
#define SNIC_IO_DONE                    BIT(2)
#define SNIC_IO_REQ_NULL                BIT(3)
#define SNIC_IO_ABTS_PENDING            BIT(4)
#define SNIC_IO_ABORTED                 BIT(5)
#define SNIC_IO_ABTS_ISSUED             BIT(6)
#define SNIC_IO_TERM_ISSUED             BIT(7)
#define SNIC_IO_ABTS_TIMEDOUT           BIT(8)
#define SNIC_IO_ABTS_TERM_DONE          BIT(9)
#define SNIC_IO_ABTS_TERM_REQ_NULL      BIT(10)
#define SNIC_IO_ABTS_TERM_TIMEDOUT      BIT(11)
#define SNIC_IO_INTERNAL_TERM_PENDING   BIT(12)
#define SNIC_IO_INTERNAL_TERM_ISSUED    BIT(13)
#define SNIC_DEVICE_RESET               BIT(14)
#define SNIC_DEV_RST_ISSUED             BIT(15)
#define SNIC_DEV_RST_TIMEDOUT           BIT(16)
#define SNIC_DEV_RST_ABTS_ISSUED        BIT(17)
#define SNIC_DEV_RST_TERM_ISSUED        BIT(18)
#define SNIC_DEV_RST_DONE               BIT(19)
#define SNIC_DEV_RST_REQ_NULL           BIT(20)
#define SNIC_DEV_RST_ABTS_DONE          BIT(21)
#define SNIC_DEV_RST_TERM_DONE          BIT(22)
#define SNIC_DEV_RST_ABTS_PENDING       BIT(23)
#define SNIC_DEV_RST_PENDING            BIT(24)
#define SNIC_DEV_RST_NOTSUP             BIT(25)
#define SNIC_SCSI_CLEANUP               BIT(26)
#define SNIC_HOST_RESET_ISSUED          BIT(27)
#define SNIC_HOST_RESET_CMD_TERM        \
        (SNIC_DEV_RST_NOTSUP | SNIC_SCSI_CLEANUP | SNIC_HOST_RESET_ISSUED)

#define SNIC_ABTS_TIMEOUT               30000           /* msec */
#define SNIC_LUN_RESET_TIMEOUT          30000           /* msec */
#define SNIC_HOST_RESET_TIMEOUT         30000           /* msec */


/*
 * These are protected by the hashed req_lock.
 */
#define CMD_SP(Cmnd)            \
        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->rqi)
#define CMD_STATE(Cmnd)         \
        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->state)
#define CMD_ABTS_STATUS(Cmnd)   \
        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->abts_status)
#define CMD_LR_STATUS(Cmnd)     \
        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->lr_status)
#define CMD_FLAGS(Cmnd) \
        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->flags)

#define SNIC_INVALID_CODE 0x100 /* Hdr Status val unused by firmware */

#define SNIC_MAX_TARGET                 256
#define SNIC_FLAGS_NONE                 (0)

/* snic module params */
extern unsigned int snic_max_qdepth;

/* snic debugging */
extern unsigned int snic_log_level;

#define SNIC_MAIN_LOGGING       0x1
#define SNIC_SCSI_LOGGING       0x2
#define SNIC_ISR_LOGGING        0x8
#define SNIC_DESC_LOGGING       0x10

#define SNIC_CHECK_LOGGING(LEVEL, CMD)          \
do {                                            \
        if (unlikely(snic_log_level & LEVEL))   \
                do {                            \
                        CMD;                    \
                } while (0);                    \
} while (0)

#define SNIC_MAIN_DBG(host, fmt, args...)       \
        SNIC_CHECK_LOGGING(SNIC_MAIN_LOGGING,           \
                shost_printk(KERN_INFO, host, fmt, ## args);)

#define SNIC_SCSI_DBG(host, fmt, args...)       \
        SNIC_CHECK_LOGGING(SNIC_SCSI_LOGGING,           \
                shost_printk(KERN_INFO, host, fmt, ##args);)

#define SNIC_DISC_DBG(host, fmt, args...)       \
        SNIC_CHECK_LOGGING(SNIC_SCSI_LOGGING,           \
                shost_printk(KERN_INFO, host, fmt, ##args);)

#define SNIC_ISR_DBG(host, fmt, args...)        \
        SNIC_CHECK_LOGGING(SNIC_ISR_LOGGING,            \
                shost_printk(KERN_INFO, host, fmt, ##args);)

#define SNIC_HOST_ERR(host, fmt, args...)               \
        shost_printk(KERN_ERR, host, fmt, ##args)

#define SNIC_HOST_INFO(host, fmt, args...)              \
        shost_printk(KERN_INFO, host, fmt, ##args)

#define SNIC_INFO(fmt, args...)                         \
        pr_info(PFX fmt, ## args)

#define SNIC_DBG(fmt, args...)                          \
        pr_info(PFX fmt, ## args)

#define SNIC_ERR(fmt, args...)                          \
        pr_err(PFX fmt, ## args)

#ifdef DEBUG
#define SNIC_BUG_ON(EXPR) \
        ({ \
                if (EXPR) { \
                        SNIC_ERR("SNIC BUG(%s)\n", #EXPR); \
                        BUG_ON(EXPR); \
                } \
        })
#else
#define SNIC_BUG_ON(EXPR) \
        ({ \
                if (EXPR) { \
                        SNIC_ERR("SNIC BUG(%s) at %s : %d\n", \
                                 #EXPR, __func__, __LINE__); \
                        WARN_ON_ONCE(EXPR); \
                } \
        })
#endif

/* Soft assert */
#define SNIC_ASSERT_NOT_IMPL(EXPR) \
        ({ \
                if (EXPR) {\
                        SNIC_INFO("Functionality not impl'ed at %s:%d\n", \
                                  __func__, __LINE__); \
                        WARN_ON_ONCE(EXPR); \
                } \
         })


extern const char *snic_state_str[];

enum snic_intx_intr_index {
        SNIC_INTX_WQ_RQ_COPYWQ,
        SNIC_INTX_ERR,
        SNIC_INTX_NOTIFY,
        SNIC_INTX_INTR_MAX,
};

enum snic_msix_intr_index {
        SNIC_MSIX_WQ,
        SNIC_MSIX_IO_CMPL,
        SNIC_MSIX_ERR_NOTIFY,
        SNIC_MSIX_INTR_MAX,
};

#define SNIC_INTRHDLR_NAMSZ     (2 * IFNAMSIZ)
struct snic_msix_entry {
        int requested;
        char devname[SNIC_INTRHDLR_NAMSZ];
        irqreturn_t (*isr)(int, void *);
        void *devid;
};

enum snic_state {
        SNIC_INIT = 0,
        SNIC_ERROR,
        SNIC_ONLINE,
        SNIC_OFFLINE,
        SNIC_FWRESET,
};

#define SNIC_WQ_MAX             1
#define SNIC_CQ_IO_CMPL_MAX     1
#define SNIC_CQ_MAX             (SNIC_WQ_MAX + SNIC_CQ_IO_CMPL_MAX)

/* firmware version information */
struct snic_fw_info {
        u32     fw_ver;
        u32     hid;                    /* u16 hid | u16 vnic id */
        u32     max_concur_ios;         /* max concurrent ios */
        u32     max_sgs_per_cmd;        /* max sgls per IO */
        u32     max_io_sz;              /* max io size supported */
        u32     hba_cap;                /* hba capabilities */
        u32     max_tgts;               /* max tgts supported */
        u16     io_tmo;                 /* FW Extended timeout */
        struct completion *wait;        /* protected by snic lock*/
};

/*
 * snic_work item : defined to process asynchronous events
 */
struct snic_work {
        struct work_struct work;
        u16     ev_id;
        u64     *ev_data;
};

/*
 * snic structure to represent SCSI vNIC
 */
struct snic {
        /* snic specific members */
        struct list_head list;
        char name[IFNAMSIZ];
        atomic_t state;
        spinlock_t snic_lock;
        struct completion *remove_wait;
        bool in_remove;
        bool stop_link_events;          /* stop processing link events */

        /* discovery related */
        struct snic_disc disc;

        /* Scsi Host info */
        struct Scsi_Host *shost;

        /* vnic related structures */
        struct vnic_dev_bar bar0;

        struct vnic_stats *stats;
        unsigned long stats_time;
        unsigned long stats_reset_time;

        struct vnic_dev *vdev;

        /* hw resource info */
        unsigned int wq_count;
        unsigned int cq_count;
        unsigned int intr_count;
        unsigned int err_intr_offset;

        int link_status; /* retrieved from svnic_dev_link_status() */
        u32 link_down_cnt;

        /* pci related */
        struct pci_dev *pdev;
        struct snic_msix_entry msix[SNIC_MSIX_INTR_MAX];

        /* io related info */
        mempool_t *req_pool[SNIC_REQ_MAX_CACHES]; /* (??) */
        ____cacheline_aligned spinlock_t io_req_lock[SNIC_IO_LOCKS];

        /* Maintain snic specific commands, cmds with no tag in spl_cmd_list */
        ____cacheline_aligned spinlock_t spl_cmd_lock;
        struct list_head spl_cmd_list;

        unsigned int max_tag_id;
        atomic_t ios_inflight;          /* io in flight counter */

        struct vnic_snic_config config;

        struct work_struct link_work;

        /* firmware information */
        struct snic_fw_info fwinfo;

        /* Work for processing Target related work */
        struct work_struct tgt_work;

        /* Work for processing Discovery */
        struct work_struct disc_work;

        /* stats related */
        unsigned int reset_stats;
        atomic64_t io_cmpl_skip;
        struct snic_stats s_stats;      /* Per SNIC driver stats */

        /* platform specific */
#ifdef CONFIG_SCSI_SNIC_DEBUG_FS
        struct dentry *stats_host;      /* Per snic debugfs root */
        struct dentry *stats_file;      /* Per snic debugfs file */
        struct dentry *reset_stats_file;/* Per snic reset stats file */
#endif

        /* completion queue cache line section */
        ____cacheline_aligned struct vnic_cq cq[SNIC_CQ_MAX];

        /* work queue cache line section */
        ____cacheline_aligned struct vnic_wq wq[SNIC_WQ_MAX];
        spinlock_t wq_lock[SNIC_WQ_MAX];

        /* interrupt resource cache line section */
        ____cacheline_aligned struct vnic_intr intr[SNIC_MSIX_INTR_MAX];
}; /* end of snic structure */

/*
 * SNIC Driver's Global Data
 */
struct snic_global {
        struct list_head snic_list;
        spinlock_t snic_list_lock;

        struct kmem_cache *req_cache[SNIC_REQ_MAX_CACHES];

        struct workqueue_struct *event_q;

#ifdef CONFIG_SCSI_SNIC_DEBUG_FS
        /* debugfs related global data */
        struct dentry *trc_root;
        struct dentry *stats_root;

        struct snic_trc trc ____cacheline_aligned;
#endif
};

extern struct snic_global *snic_glob;

int snic_glob_init(void);
void snic_glob_cleanup(void);

extern struct workqueue_struct *snic_event_queue;
extern const struct attribute_group *snic_host_groups[];

enum scsi_qc_status snic_queuecommand(struct Scsi_Host *shost,
                                      struct scsi_cmnd *sc);
int snic_abort_cmd(struct scsi_cmnd *);
int snic_device_reset(struct scsi_cmnd *);
int snic_host_reset(struct scsi_cmnd *);
int snic_reset(struct Scsi_Host *, struct scsi_cmnd *);
void snic_shutdown_scsi_cleanup(struct snic *);


int snic_request_intr(struct snic *);
void snic_free_intr(struct snic *);
int snic_set_intr_mode(struct snic *);
void snic_clear_intr_mode(struct snic *);

int snic_fwcq_cmpl_handler(struct snic *, int);
int snic_wq_cmpl_handler(struct snic *, int);
void snic_free_wq_buf(struct vnic_wq *, struct vnic_wq_buf *);


void snic_log_q_error(struct snic *);
void snic_handle_link_event(struct snic *);
void snic_handle_link(struct work_struct *);

int snic_queue_exch_ver_req(struct snic *);
void snic_io_exch_ver_cmpl_handler(struct snic *, struct snic_fw_req *);

int snic_queue_wq_desc(struct snic *, void *os_buf, u16 len);

void snic_handle_untagged_req(struct snic *, struct snic_req_info *);
void snic_release_untagged_req(struct snic *, struct snic_req_info *);
void snic_free_all_untagged_reqs(struct snic *);
int snic_get_conf(struct snic *);
void snic_set_state(struct snic *, enum snic_state);
int snic_get_state(struct snic *);
const char *snic_state_to_str(unsigned int);
void snic_hex_dump(char *, char *, int);
void snic_print_desc(const char *fn, char *os_buf, int len);
const char *show_opcode_name(int val);
#endif /* _SNIC_H */