/*
 * mtip32xx.h - Header file for the P320 SSD Block Driver
 *   Copyright (C) 2011 Micron Technology, Inc.
 *
 * Portions of this code were derived from works subjected to the
 * following copyright:
 *    Copyright (C) 2009 Integrated Device Technology, Inc.
 *
 * 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.
 *
 */

#ifndef __MTIP32XX_H__
#define __MTIP32XX_H__

#include <linux/spinlock.h>
#include <linux/rwsem.h>
#include <linux/ata.h>
#include <linux/interrupt.h>
#include <linux/genhd.h>

/* Offset of Subsystem Device ID in pci confoguration space */
#define PCI_SUBSYSTEM_DEVICEID  0x2E

/* offset of Device Control register in PCIe extended capabilites space */
#define PCIE_CONFIG_EXT_DEVICE_CONTROL_OFFSET   0x48

/* check for erase mode support during secure erase */
#define MTIP_SEC_ERASE_MODE     0x2

/* # of times to retry timed out/failed IOs */
#define MTIP_MAX_RETRIES        2

/* Various timeout values in ms */
#define MTIP_NCQ_CMD_TIMEOUT_MS      15000
#define MTIP_IOCTL_CMD_TIMEOUT_MS    5000
#define MTIP_INT_CMD_TIMEOUT_MS      5000
#define MTIP_QUIESCE_IO_TIMEOUT_MS   (MTIP_NCQ_CMD_TIMEOUT_MS * \
                                     (MTIP_MAX_RETRIES + 1))

/* check for timeouts every 500ms */
#define MTIP_TIMEOUT_CHECK_PERIOD       500

/* ftl rebuild */
#define MTIP_FTL_REBUILD_OFFSET         142
#define MTIP_FTL_REBUILD_MAGIC          0xED51
#define MTIP_FTL_REBUILD_TIMEOUT_MS     2400000

/* unaligned IO handling */
#define MTIP_MAX_UNALIGNED_SLOTS        2

/* Macro to extract the tag bit number from a tag value. */
#define MTIP_TAG_BIT(tag)       (tag & 0x1F)

/*
 * Macro to extract the tag index from a tag value. The index
 * is used to access the correct s_active/Command Issue register based
 * on the tag value.
 */
#define MTIP_TAG_INDEX(tag)     (tag >> 5)

/*
 * Maximum number of scatter gather entries
 * a single command may have.
 */
#define MTIP_MAX_SG             504

/*
 * Maximum number of slot groups (Command Issue & s_active registers)
 * NOTE: This is the driver maximum; check dd->slot_groups for actual value.
 */
#define MTIP_MAX_SLOT_GROUPS    8

/* Internal command tag. */
#define MTIP_TAG_INTERNAL       0

/* Micron Vendor ID & P320x SSD Device ID */
#define PCI_VENDOR_ID_MICRON    0x1344
#define P320H_DEVICE_ID         0x5150
#define P320M_DEVICE_ID         0x5151
#define P320S_DEVICE_ID         0x5152
#define P325M_DEVICE_ID         0x5153
#define P420H_DEVICE_ID         0x5160
#define P420M_DEVICE_ID         0x5161
#define P425M_DEVICE_ID         0x5163

/* Driver name and version strings */
#define MTIP_DRV_NAME           "mtip32xx"
#define MTIP_DRV_VERSION        "1.3.1"

/* Maximum number of minor device numbers per device. */
#define MTIP_MAX_MINORS         16

/* Maximum number of supported command slots. */
#define MTIP_MAX_COMMAND_SLOTS  (MTIP_MAX_SLOT_GROUPS * 32)

/*
 * Per-tag bitfield size in longs.
 * Linux bit manipulation functions
 * (i.e. test_and_set_bit, find_next_zero_bit)
 * manipulate memory in longs, so we try to make the math work.
 * take the slot groups and find the number of longs, rounding up.
 * Careful! i386 and x86_64 use different size longs!
 */
#define U32_PER_LONG    (sizeof(long) / sizeof(u32))
#define SLOTBITS_IN_LONGS ((MTIP_MAX_SLOT_GROUPS + \
                                        (U32_PER_LONG-1))/U32_PER_LONG)

/* BAR number used to access the HBA registers. */
#define MTIP_ABAR               5

#ifdef DEBUG
 #define dbg_printk(format, arg...)     \
        printk(pr_fmt(format), ##arg);
#else
 #define dbg_printk(format, arg...)
#endif

#define MTIP_DFS_MAX_BUF_SIZE 1024

#define __force_bit2int (unsigned int __force)

enum {
        /* below are bit numbers in 'flags' defined in mtip_port */
        MTIP_PF_IC_ACTIVE_BIT       = 0, /* pio/ioctl */
        MTIP_PF_EH_ACTIVE_BIT       = 1, /* error handling */
        MTIP_PF_SE_ACTIVE_BIT       = 2, /* secure erase */
        MTIP_PF_DM_ACTIVE_BIT       = 3, /* download microcde */
        MTIP_PF_PAUSE_IO      = ((1 << MTIP_PF_IC_ACTIVE_BIT) |
                                (1 << MTIP_PF_EH_ACTIVE_BIT) |
                                (1 << MTIP_PF_SE_ACTIVE_BIT) |
                                (1 << MTIP_PF_DM_ACTIVE_BIT)),

        MTIP_PF_SVC_THD_ACTIVE_BIT  = 4,
        MTIP_PF_ISSUE_CMDS_BIT      = 5,
        MTIP_PF_REBUILD_BIT         = 6,
        MTIP_PF_SR_CLEANUP_BIT      = 7,
        MTIP_PF_SVC_THD_STOP_BIT    = 8,

        /* below are bit numbers in 'dd_flag' defined in driver_data */
        MTIP_DDF_SEC_LOCK_BIT       = 0,
        MTIP_DDF_REMOVE_PENDING_BIT = 1,
        MTIP_DDF_OVER_TEMP_BIT      = 2,
        MTIP_DDF_WRITE_PROTECT_BIT  = 3,
        MTIP_DDF_REMOVE_DONE_BIT    = 4,
        MTIP_DDF_CLEANUP_BIT        = 5,
        MTIP_DDF_RESUME_BIT         = 6,
        MTIP_DDF_INIT_DONE_BIT      = 7,
        MTIP_DDF_REBUILD_FAILED_BIT = 8,

        MTIP_DDF_STOP_IO      = ((1 << MTIP_DDF_REMOVE_PENDING_BIT) |
                                (1 << MTIP_DDF_SEC_LOCK_BIT) |
                                (1 << MTIP_DDF_OVER_TEMP_BIT) |
                                (1 << MTIP_DDF_WRITE_PROTECT_BIT) |
                                (1 << MTIP_DDF_REBUILD_FAILED_BIT)),

};

struct smart_attr {
        u8 attr_id;
        u16 flags;
        u8 cur;
        u8 worst;
        u32 data;
        u8 res[3];
} __packed;

struct mtip_work {
        struct work_struct work;
        void *port;
        int cpu_binding;
        u32 completed;
} ____cacheline_aligned_in_smp;

#define DEFINE_HANDLER(group)                                  \
        void mtip_workq_sdbf##group(struct work_struct *work)       \
        {                                                      \
                struct mtip_work *w = (struct mtip_work *) work;         \
                mtip_workq_sdbfx(w->port, group, w->completed);     \
        }

#define MTIP_TRIM_TIMEOUT_MS            240000
#define MTIP_MAX_TRIM_ENTRIES           8
#define MTIP_MAX_TRIM_ENTRY_LEN         0xfff8

struct mtip_trim_entry {
        u32 lba;   /* starting lba of region */
        u16 rsvd;  /* unused */
        u16 range; /* # of 512b blocks to trim */
} __packed;

struct mtip_trim {
        /* Array of regions to trim */
        struct mtip_trim_entry entry[MTIP_MAX_TRIM_ENTRIES];
} __packed;

/* Register Frame Information Structure (FIS), host to device. */
struct host_to_dev_fis {
        /*
         * FIS type.
         * - 27h Register FIS, host to device.
         * - 34h Register FIS, device to host.
         * - 39h DMA Activate FIS, device to host.
         * - 41h DMA Setup FIS, bi-directional.
         * - 46h Data FIS, bi-directional.
         * - 58h BIST Activate FIS, bi-directional.
         * - 5Fh PIO Setup FIS, device to host.
         * - A1h Set Device Bits FIS, device to host.
         */
        unsigned char type;
        unsigned char opts;
        unsigned char command;
        unsigned char features;

        union {
                unsigned char lba_low;
                unsigned char sector;
        };
        union {
                unsigned char lba_mid;
                unsigned char cyl_low;
        };
        union {
                unsigned char lba_hi;
                unsigned char cyl_hi;
        };
        union {
                unsigned char device;
                unsigned char head;
        };

        union {
                unsigned char lba_low_ex;
                unsigned char sector_ex;
        };
        union {
                unsigned char lba_mid_ex;
                unsigned char cyl_low_ex;
        };
        union {
                unsigned char lba_hi_ex;
                unsigned char cyl_hi_ex;
        };
        unsigned char features_ex;

        unsigned char sect_count;
        unsigned char sect_cnt_ex;
        unsigned char res2;
        unsigned char control;

        unsigned int res3;
};

/* Command header structure. */
struct mtip_cmd_hdr {
        /*
         * Command options.
         * - Bits 31:16 Number of PRD entries.
         * - Bits 15:8 Unused in this implementation.
         * - Bit 7 Prefetch bit, informs the drive to prefetch PRD entries.
         * - Bit 6 Write bit, should be set when writing data to the device.
         * - Bit 5 Unused in this implementation.
         * - Bits 4:0 Length of the command FIS in DWords (DWord = 4 bytes).
         */
        unsigned int opts;
        /* This field is unsed when using NCQ. */
        union {
                unsigned int byte_count;
                unsigned int status;
        };
        /*
         * Lower 32 bits of the command table address associated with this
         * header. The command table addresses must be 128 byte aligned.
         */
        unsigned int ctba;
        /*
         * If 64 bit addressing is used this field is the upper 32 bits
         * of the command table address associated with this command.
         */
        unsigned int ctbau;
        /* Reserved and unused. */
        unsigned int res[4];
};

/* Command scatter gather structure (PRD). */
struct mtip_cmd_sg {
        /*
         * Low 32 bits of the data buffer address. For P320 this
         * address must be 8 byte aligned signified by bits 2:0 being
         * set to 0.
         */
        unsigned int dba;
        /*
         * When 64 bit addressing is used this field is the upper
         * 32 bits of the data buffer address.
         */
        unsigned int dba_upper;
        /* Unused. */
        unsigned int reserved;
        /*
         * Bit 31: interrupt when this data block has been transferred.
         * Bits 30..22: reserved
         * Bits 21..0: byte count (minus 1).  For P320 the byte count must be
         * 8 byte aligned signified by bits 2:0 being set to 1.
         */
        unsigned int info;
};
struct mtip_port;

/* Structure used to describe a command. */
struct mtip_cmd {

        struct mtip_cmd_hdr *command_header; /* ptr to command header entry */

        dma_addr_t command_header_dma; /* corresponding physical address */

        void *command; /* ptr to command table entry */

        dma_addr_t command_dma; /* corresponding physical address */

        void *comp_data; /* data passed to completion function comp_func() */
        /*
         * Completion function called by the ISR upon completion of
         * a command.
         */
        void (*comp_func)(struct mtip_port *port,
                                int tag,
                                struct mtip_cmd *cmd,
                                int status);

        int scatter_ents; /* Number of scatter list entries used */

        int unaligned; /* command is unaligned on 4k boundary */

        struct scatterlist sg[MTIP_MAX_SG]; /* Scatter list entries */

        int retries; /* The number of retries left for this command. */

        int direction; /* Data transfer direction */
};

/* Structure used to describe a port. */
struct mtip_port {
        /* Pointer back to the driver data for this port. */
        struct driver_data *dd;
        /*
         * Used to determine if the data pointed to by the
         * identify field is valid.
         */
        unsigned long identify_valid;
        /* Base address of the memory mapped IO for the port. */
        void __iomem *mmio;
        /* Array of pointers to the memory mapped s_active registers. */
        void __iomem *s_active[MTIP_MAX_SLOT_GROUPS];
        /* Array of pointers to the memory mapped completed registers. */
        void __iomem *completed[MTIP_MAX_SLOT_GROUPS];
        /* Array of pointers to the memory mapped Command Issue registers. */
        void __iomem *cmd_issue[MTIP_MAX_SLOT_GROUPS];
        /*
         * Pointer to the beginning of the command header memory as used
         * by the driver.
         */
        void *command_list;
        /*
         * Pointer to the beginning of the command header memory as used
         * by the DMA.
         */
        dma_addr_t command_list_dma;
        /*
         * Pointer to the beginning of the RX FIS memory as used
         * by the driver.
         */
        void *rxfis;
        /*
         * Pointer to the beginning of the RX FIS memory as used
         * by the DMA.
         */
        dma_addr_t rxfis_dma;
        /*
         * Pointer to the DMA region for RX Fis, Identify, RLE10, and SMART
         */
        void *block1;
        /*
         * DMA address of region for RX Fis, Identify, RLE10, and SMART
         */
        dma_addr_t block1_dma;
        /*
         * Pointer to the beginning of the identify data memory as used
         * by the driver.
         */
        u16 *identify;
        /*
         * Pointer to the beginning of the identify data memory as used
         * by the DMA.
         */
        dma_addr_t identify_dma;
        /*
         * Pointer to the beginning of a sector buffer that is used
         * by the driver when issuing internal commands.
         */
        u16 *sector_buffer;
        /*
         * Pointer to the beginning of a sector buffer that is used
         * by the DMA when the driver issues internal commands.
         */
        dma_addr_t sector_buffer_dma;
        /*
         * Bit significant, used to determine if a command slot has
         * been allocated. i.e. the slot is in use.  Bits are cleared
         * when the command slot and all associated data structures
         * are no longer needed.
         */
        u16 *log_buf;
        dma_addr_t log_buf_dma;

        u8 *smart_buf;
        dma_addr_t smart_buf_dma;

        unsigned long allocated[SLOTBITS_IN_LONGS];
        /*
         * used to queue commands when an internal command is in progress
         * or error handling is active
         */
        unsigned long cmds_to_issue[SLOTBITS_IN_LONGS];
        /* Used by mtip_service_thread to wait for an event */
        wait_queue_head_t svc_wait;
        /*
         * indicates the state of the port. Also, helps the service thread
         * to determine its action on wake up.
         */
        unsigned long flags;
        /*
         * Timer used to complete commands that have been active for too long.
         */
        unsigned long ic_pause_timer;

        /* Semaphore to control queue depth of unaligned IOs */
        struct semaphore cmd_slot_unal;

        /* Spinlock for working around command-issue bug. */
        spinlock_t cmd_issue_lock[MTIP_MAX_SLOT_GROUPS];
};

/*
 * Driver private data structure.
 *
 * One structure is allocated per probed device.
 */
struct driver_data {
        void __iomem *mmio; /* Base address of the HBA registers. */

        int major; /* Major device number. */

        int instance; /* Instance number. First device probed is 0, ... */

        struct gendisk *disk; /* Pointer to our gendisk structure. */

        struct pci_dev *pdev; /* Pointer to the PCI device structure. */

        struct request_queue *queue; /* Our request queue. */

        struct blk_mq_tag_set tags; /* blk_mq tags */

        struct mtip_port *port; /* Pointer to the port data structure. */

        unsigned product_type; /* magic value declaring the product type */

        unsigned slot_groups; /* number of slot groups the product supports */

        unsigned long index; /* Index to determine the disk name */

        unsigned long dd_flag; /* NOTE: use atomic bit operations on this */

        struct task_struct *mtip_svc_handler; /* task_struct of svc thd */

        struct dentry *dfs_node;

        bool trim_supp; /* flag indicating trim support */

        bool sr;

        int numa_node; /* NUMA support */

        char workq_name[32];

        struct workqueue_struct *isr_workq;

        atomic_t irq_workers_active;

        struct mtip_work work[MTIP_MAX_SLOT_GROUPS];

        int isr_binding;

        struct block_device *bdev;

        struct list_head online_list; /* linkage for online list */

        struct list_head remove_list; /* linkage for removing list */

        int unal_qdepth; /* qdepth of unaligned IO queue */
};

#endif