/* SPDX-License-Identifier: GPL-2.0 */
/* -*- mode: c; c-basic-offset: 8 -*- */

/* Driver for 53c700 and 53c700-66 chips from NCR and Symbios
 *
 * Copyright (C) 2001 by James.Bottomley@HansenPartnership.com
 */

#ifndef _53C700_H
#define _53C700_H

#include <linux/interrupt.h>
#include <asm/io.h>

#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>

/* Turn on for general debugging---too verbose for normal use */
#undef  NCR_700_DEBUG
/* Debug the tag queues, checking hash queue allocation and deallocation
 * and search for duplicate tags */
#undef NCR_700_TAG_DEBUG

#ifdef NCR_700_DEBUG
#define DEBUG(x)        printk x
#define DDEBUG(prefix, sdev, fmt, a...) \
        sdev_printk(prefix, sdev, fmt, ##a)
#define CDEBUG(prefix, scmd, fmt, a...) \
        scmd_printk(prefix, scmd, fmt, ##a)
#else
#define DEBUG(x)        do {} while (0)
#define DDEBUG(prefix, scmd, fmt, a...) do {} while (0)
#define CDEBUG(prefix, scmd, fmt, a...) do {} while (0)
#endif

/* The number of available command slots */
#define NCR_700_COMMAND_SLOTS_PER_HOST  64
/* The maximum number of Scatter Gathers we allow */
#define NCR_700_SG_SEGMENTS             32
/* The maximum number of luns (make this of the form 2^n) */
#define NCR_700_MAX_LUNS                32
#define NCR_700_LUN_MASK                (NCR_700_MAX_LUNS - 1)
/* Maximum number of tags the driver ever allows per device */
#define NCR_700_MAX_TAGS                16
/* Tag depth the driver starts out with (can be altered in sysfs) */
#define NCR_700_DEFAULT_TAGS            4
/* This is the default number of commands per LUN in the untagged case.
 * two is a good value because it means we can have one command active and
 * one command fully prepared and waiting
 */
#define NCR_700_CMD_PER_LUN             2
/* magic byte identifying an internally generated REQUEST_SENSE command */
#define NCR_700_INTERNAL_SENSE_MAGIC    0x42

struct NCR_700_Host_Parameters;

/* These are the externally used routines */
struct Scsi_Host *NCR_700_detect(struct scsi_host_template *,
                struct NCR_700_Host_Parameters *, struct device *);
int NCR_700_release(struct Scsi_Host *host);
irqreturn_t NCR_700_intr(int, void *);


enum NCR_700_Host_State {
        NCR_700_HOST_BUSY,
        NCR_700_HOST_FREE,
};

struct NCR_700_SG_List {
        /* The following is a script fragment to move the buffer onto the
         * bus and then link the next fragment or return */
        #define SCRIPT_MOVE_DATA_IN             0x09000000
        #define SCRIPT_MOVE_DATA_OUT            0x08000000
        __u32   ins;
        __u32   pAddr;
        #define SCRIPT_NOP                      0x80000000
        #define SCRIPT_RETURN                   0x90080000
};

struct NCR_700_Device_Parameters {
        /* space for creating a request sense command. Really, except
         * for the annoying SCSI-2 requirement for LUN information in
         * cmnd[1], this could be in static storage */
        unsigned char cmnd[MAX_COMMAND_SIZE];
        __u8    depth;
        struct scsi_cmnd *current_cmnd; /* currently active command */
};


/* The SYNC negotiation sequence looks like:
 * 
 * If DEV_NEGOTIATED_SYNC not set, tack and SDTR message on to the
 * initial identify for the device and set DEV_BEGIN_SYNC_NEGOTATION
 * If we get an SDTR reply, work out the SXFER parameters, squirrel
 * them away here, clear DEV_BEGIN_SYNC_NEGOTIATION and set
 * DEV_NEGOTIATED_SYNC.  If we get a REJECT msg, squirrel
 *
 *
 * 0:7  SXFER_REG negotiated value for this device
 * 8:15 Current queue depth
 * 16   negotiated SYNC flag
 * 17 begin SYNC negotiation flag 
 * 18 device supports tag queueing */
#define NCR_700_DEV_NEGOTIATED_SYNC     (1<<16)
#define NCR_700_DEV_BEGIN_SYNC_NEGOTIATION      (1<<17)
#define NCR_700_DEV_PRINT_SYNC_NEGOTIATION (1<<19)

static inline char *NCR_700_get_sense_cmnd(struct scsi_device *SDp)
{
        struct NCR_700_Device_Parameters *hostdata = SDp->hostdata;

        return hostdata->cmnd;
}

static inline void
NCR_700_set_depth(struct scsi_device *SDp, __u8 depth)
{
        struct NCR_700_Device_Parameters *hostdata = SDp->hostdata;

        hostdata->depth = depth;
}
static inline __u8
NCR_700_get_depth(struct scsi_device *SDp)
{
        struct NCR_700_Device_Parameters *hostdata = SDp->hostdata;

        return hostdata->depth;
}
static inline int
NCR_700_is_flag_set(struct scsi_device *SDp, __u32 flag)
{
        return (spi_flags(SDp->sdev_target) & flag) == flag;
}
static inline int
NCR_700_is_flag_clear(struct scsi_device *SDp, __u32 flag)
{
        return (spi_flags(SDp->sdev_target) & flag) == 0;
}
static inline void
NCR_700_set_flag(struct scsi_device *SDp, __u32 flag)
{
        spi_flags(SDp->sdev_target) |= flag;
}
static inline void
NCR_700_clear_flag(struct scsi_device *SDp, __u32 flag)
{
        spi_flags(SDp->sdev_target) &= ~flag;
}

enum NCR_700_tag_neg_state {
        NCR_700_START_TAG_NEGOTIATION = 0,
        NCR_700_DURING_TAG_NEGOTIATION = 1,
        NCR_700_FINISHED_TAG_NEGOTIATION = 2,
};

static inline enum NCR_700_tag_neg_state
NCR_700_get_tag_neg_state(struct scsi_device *SDp)
{
        return (enum NCR_700_tag_neg_state)((spi_flags(SDp->sdev_target)>>20) & 0x3);
}

static inline void
NCR_700_set_tag_neg_state(struct scsi_device *SDp,
                          enum NCR_700_tag_neg_state state)
{
        /* clear the slot */
        spi_flags(SDp->sdev_target) &= ~(0x3 << 20);
        spi_flags(SDp->sdev_target) |= ((__u32)state) << 20;
}

struct NCR_700_command_slot {
        struct NCR_700_SG_List  SG[NCR_700_SG_SEGMENTS+1];
        struct NCR_700_SG_List  *pSG;
        #define NCR_700_SLOT_MASK 0xFC
        #define NCR_700_SLOT_MAGIC 0xb8
        #define NCR_700_SLOT_FREE (0|NCR_700_SLOT_MAGIC) /* slot may be used */
        #define NCR_700_SLOT_BUSY (1|NCR_700_SLOT_MAGIC) /* slot has command active on HA */
        #define NCR_700_SLOT_QUEUED (2|NCR_700_SLOT_MAGIC) /* slot has command to be made active on HA */
        __u8    state;
        #define NCR_700_FLAG_AUTOSENSE  0x01
        __u8    flags;
        __u8    pad1[2];        /* Needed for m68k where min alignment is 2 bytes */
        int     tag;
        __u32   resume_offset;
        struct scsi_cmnd *cmnd;
        /* The pci_mapped address of the actual command in cmnd */
        dma_addr_t      pCmd;
        __u32           temp;
        /* if this command is a pci_single mapping, holds the dma address
         * for later unmapping in the done routine */
        dma_addr_t      dma_handle;
        /* historical remnant, now used to link free commands */
        struct NCR_700_command_slot *ITL_forw;
};

struct NCR_700_Host_Parameters {
        /* These must be filled in by the calling driver */
        int     clock;                  /* board clock speed in MHz */
        void __iomem    *base;          /* the base for the port (copied to host) */
        struct device   *dev;
        __u32   dmode_extra;    /* adjustable bus settings */
        __u32   dcntl_extra;    /* adjustable bus settings */
        __u32   ctest7_extra;   /* adjustable bus settings */
        __u32   differential:1; /* if we are differential */
#ifdef CONFIG_53C700_LE_ON_BE
        /* This option is for HP only.  Set it if your chip is wired for
         * little endian on this platform (which is big endian) */
        __u32   force_le_on_be:1;
#endif
        __u32   chip710:1;      /* set if really a 710 not 700 */
        __u32   burst_length:4; /* set to 0 to disable 710 bursting */

        /* NOTHING BELOW HERE NEEDS ALTERING */
        __u32   fast:1;         /* if we can alter the SCSI bus clock
                                   speed (so can negiotiate sync) */
        int     sync_clock;     /* The speed of the SYNC core */

        __u32   *script;                /* pointer to script location */
        __u32   pScript;                /* physical mem addr of script */

        enum NCR_700_Host_State state; /* protected by state lock */
        struct scsi_cmnd *cmd;
        /* Note: pScript contains the single consistent block of
         * memory.  All the msgin, msgout and status are allocated in
         * this memory too (at separate cache lines).  TOTAL_MEM_SIZE
         * represents the total size of this area */
#define MSG_ARRAY_SIZE  8
#define MSGOUT_OFFSET   (L1_CACHE_ALIGN(sizeof(SCRIPT)))
        __u8    *msgout;
#define MSGIN_OFFSET    (MSGOUT_OFFSET + L1_CACHE_ALIGN(MSG_ARRAY_SIZE))
        __u8    *msgin;
#define STATUS_OFFSET   (MSGIN_OFFSET + L1_CACHE_ALIGN(MSG_ARRAY_SIZE))
        __u8    *status;
#define SLOTS_OFFSET    (STATUS_OFFSET + L1_CACHE_ALIGN(MSG_ARRAY_SIZE))
        struct NCR_700_command_slot     *slots;
#define TOTAL_MEM_SIZE  (SLOTS_OFFSET + L1_CACHE_ALIGN(sizeof(struct NCR_700_command_slot) * NCR_700_COMMAND_SLOTS_PER_HOST))
        int     saved_slot_position;
        int     command_slot_count; /* protected by state lock */
        __u8    tag_negotiated;
        __u8    rev;
        __u8    reselection_id;
        __u8    min_period;

        /* Free list, singly linked by ITL_forw elements */
        struct NCR_700_command_slot *free_list;
        /* Completion for waited for ops, like reset, abort or
         * device reset.
         *
         * NOTE: relies on single threading in the error handler to
         * have only one outstanding at once */
        struct completion *eh_complete;
};

/*
 *      53C700 Register Interface - the offset from the Selected base
 *      I/O address */
#ifdef CONFIG_53C700_LE_ON_BE
#define bE      (hostdata->force_le_on_be ? 0 : 3)
#define bSWAP   (hostdata->force_le_on_be)
#define bEBus   (!hostdata->force_le_on_be)
#elif defined(__BIG_ENDIAN)
#define bE      3
#define bSWAP   0
#elif defined(__LITTLE_ENDIAN)
#define bE      0
#define bSWAP   0
#else
#error "__BIG_ENDIAN or __LITTLE_ENDIAN must be defined, did you include byteorder.h?"
#endif
#ifndef bEBus
#ifdef CONFIG_53C700_BE_BUS
#define bEBus   1
#else
#define bEBus   0
#endif
#endif
#define bS_to_cpu(x)    (bSWAP ? le32_to_cpu(x) : (x))
#define bS_to_host(x)   (bSWAP ? cpu_to_le32(x) : (x))

/* NOTE: These registers are in the LE register space only, the required byte
 * swapping is done by the NCR_700_{read|write}[b] functions */
#define SCNTL0_REG                      0x00
#define         FULL_ARBITRATION        0xc0
#define         PARITY                  0x08
#define         ENABLE_PARITY           0x04
#define         AUTO_ATN                0x02
#define SCNTL1_REG                      0x01
#define         SLOW_BUS                0x80
#define         ENABLE_SELECT           0x20
#define         ASSERT_RST              0x08
#define         ASSERT_EVEN_PARITY      0x04
#define SDID_REG                        0x02
#define SIEN_REG                        0x03
#define         PHASE_MM_INT            0x80
#define         FUNC_COMP_INT           0x40
#define         SEL_TIMEOUT_INT         0x20
#define         SELECT_INT              0x10
#define         GROSS_ERR_INT           0x08
#define         UX_DISC_INT             0x04
#define         RST_INT                 0x02
#define         PAR_ERR_INT             0x01
#define SCID_REG                        0x04
#define SXFER_REG                       0x05
#define         ASYNC_OPERATION         0x00
#define SODL_REG                        0x06
#define SOCL_REG                        0x07
#define SFBR_REG                        0x08
#define SIDL_REG                        0x09
#define SBDL_REG                        0x0A
#define SBCL_REG                        0x0B
/* read bits */
#define         SBCL_IO                 0x01
/*write bits */
#define         SYNC_DIV_AS_ASYNC       0x00
#define         SYNC_DIV_1_0            0x01
#define         SYNC_DIV_1_5            0x02
#define         SYNC_DIV_2_0            0x03
#define DSTAT_REG                       0x0C
#define         ILGL_INST_DETECTED      0x01
#define         WATCH_DOG_INTERRUPT     0x02
#define         SCRIPT_INT_RECEIVED     0x04
#define         ABORTED                 0x10
#define SSTAT0_REG                      0x0D
#define         PARITY_ERROR            0x01
#define         SCSI_RESET_DETECTED     0x02
#define         UNEXPECTED_DISCONNECT   0x04
#define         SCSI_GROSS_ERROR        0x08
#define         SELECTED                0x10
#define         SELECTION_TIMEOUT       0x20
#define         FUNCTION_COMPLETE       0x40
#define         PHASE_MISMATCH          0x80
#define SSTAT1_REG                      0x0E
#define         SIDL_REG_FULL           0x80
#define         SODR_REG_FULL           0x40
#define         SODL_REG_FULL           0x20
#define SSTAT2_REG                      0x0F
#define CTEST0_REG                      0x14
#define         BTB_TIMER_DISABLE       0x40
#define CTEST1_REG                      0x15
#define CTEST2_REG                      0x16
#define CTEST3_REG                      0x17
#define CTEST4_REG                      0x18
#define         DISABLE_FIFO            0x00
#define         SLBE                    0x10
#define         SFWR                    0x08
#define         BYTE_LANE0              0x04
#define         BYTE_LANE1              0x05
#define         BYTE_LANE2              0x06
#define         BYTE_LANE3              0x07
#define         SCSI_ZMODE              0x20
#define         ZMODE                   0x40
#define CTEST5_REG                      0x19
#define         MASTER_CONTROL          0x10
#define         DMA_DIRECTION           0x08
#define CTEST7_REG                      0x1B
#define         BURST_DISABLE           0x80 /* 710 only */
#define         SEL_TIMEOUT_DISABLE     0x10 /* 710 only */
#define         DFP                     0x08
#define         EVP                     0x04
#define         CTEST7_TT1              0x02
#define         DIFF                    0x01
#define CTEST6_REG                      0x1A
#define TEMP_REG                        0x1C
#define DFIFO_REG                       0x20
#define         FLUSH_DMA_FIFO          0x80
#define         CLR_FIFO                0x40
#define ISTAT_REG                       0x21
#define         ABORT_OPERATION         0x80
#define         SOFTWARE_RESET_710      0x40
#define         DMA_INT_PENDING         0x01
#define         SCSI_INT_PENDING        0x02
#define         CONNECTED               0x08
#define CTEST8_REG                      0x22
#define         LAST_DIS_ENBL           0x01
#define         SHORTEN_FILTERING       0x04
#define         ENABLE_ACTIVE_NEGATION  0x10
#define         GENERATE_RECEIVE_PARITY 0x20
#define         CLR_FIFO_710            0x04
#define         FLUSH_DMA_FIFO_710      0x08
#define CTEST9_REG                      0x23
#define DBC_REG                         0x24
#define DCMD_REG                        0x27
#define DNAD_REG                        0x28
#define DIEN_REG                        0x39
#define         BUS_FAULT               0x20
#define         ABORT_INT               0x10
#define         INT_INST_INT            0x04
#define         WD_INT                  0x02
#define         ILGL_INST_INT           0x01
#define DCNTL_REG                       0x3B
#define         SOFTWARE_RESET          0x01
#define         COMPAT_700_MODE         0x01
#define         SCRPTS_16BITS           0x20
#define         EA_710                  0x20
#define         ASYNC_DIV_2_0           0x00
#define         ASYNC_DIV_1_5           0x40
#define         ASYNC_DIV_1_0           0x80
#define         ASYNC_DIV_3_0           0xc0
#define DMODE_710_REG                   0x38
#define DMODE_700_REG                   0x34
#define         BURST_LENGTH_1          0x00
#define         BURST_LENGTH_2          0x40
#define         BURST_LENGTH_4          0x80
#define         BURST_LENGTH_8          0xC0
#define         DMODE_FC1               0x10
#define         DMODE_FC2               0x20
#define         BW16                    32 
#define         MODE_286                16
#define         IO_XFER                 8
#define         FIXED_ADDR              4

#define DSP_REG                         0x2C
#define DSPS_REG                        0x30

/* Parameters to begin SDTR negotiations.  Empirically, I find that
 * the 53c700-66 cannot handle an offset >8, so don't change this  */
#define NCR_700_MAX_OFFSET      8
/* Was hoping the max offset would be greater for the 710, but
 * empirically it seems to be 8 also */
#define NCR_710_MAX_OFFSET      8
#define NCR_700_MIN_XFERP       1
#define NCR_710_MIN_XFERP       0
#define NCR_700_MIN_PERIOD      25 /* for SDTR message, 100ns */

#define script_patch_32(dev, script, symbol, value) \
{ \
        int i; \
        dma_addr_t da = value; \
        for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
                __u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]) + da; \
                (script)[A_##symbol##_used[i]] = bS_to_host(val); \
                dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
                DEBUG((" script, patching %s at %d to %pad\n", \
                       #symbol, A_##symbol##_used[i], &da)); \
        } \
}

#define script_patch_32_abs(dev, script, symbol, value) \
{ \
        int i; \
        dma_addr_t da = value; \
        for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
                (script)[A_##symbol##_used[i]] = bS_to_host(da); \
                dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
                DEBUG((" script, patching %s at %d to %pad\n", \
                       #symbol, A_##symbol##_used[i], &da)); \
        } \
}

/* Used for patching the SCSI ID in the SELECT instruction */
#define script_patch_ID(dev, script, symbol, value) \
{ \
        int i; \
        for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
                __u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]); \
                val &= 0xff00ffff; \
                val |= ((value) & 0xff) << 16; \
                (script)[A_##symbol##_used[i]] = bS_to_host(val); \
                dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
                DEBUG((" script, patching ID field %s at %d to 0x%x\n", \
                       #symbol, A_##symbol##_used[i], val)); \
        } \
}

#define script_patch_16(dev, script, symbol, value) \
{ \
        int i; \
        for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
                __u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]); \
                val &= 0xffff0000; \
                val |= ((value) & 0xffff); \
                (script)[A_##symbol##_used[i]] = bS_to_host(val); \
                dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
                DEBUG((" script, patching short field %s at %d to 0x%x\n", \
                       #symbol, A_##symbol##_used[i], val)); \
        } \
}


static inline __u8
NCR_700_readb(struct Scsi_Host *host, __u32 reg)
{
        const struct NCR_700_Host_Parameters *hostdata
                = (struct NCR_700_Host_Parameters *)host->hostdata[0];

        return ioread8(hostdata->base + (reg^bE));
}

static inline __u32
NCR_700_readl(struct Scsi_Host *host, __u32 reg)
{
        const struct NCR_700_Host_Parameters *hostdata
                = (struct NCR_700_Host_Parameters *)host->hostdata[0];
        __u32 value = bEBus ? ioread32be(hostdata->base + reg) :
                ioread32(hostdata->base + reg);
#if 1
        /* sanity check the register */
        BUG_ON((reg & 0x3) != 0);
#endif

        return value;
}

static inline void
NCR_700_writeb(__u8 value, struct Scsi_Host *host, __u32 reg)
{
        const struct NCR_700_Host_Parameters *hostdata
                = (struct NCR_700_Host_Parameters *)host->hostdata[0];

        iowrite8(value, hostdata->base + (reg^bE));
}

static inline void
NCR_700_writel(__u32 value, struct Scsi_Host *host, __u32 reg)
{
        const struct NCR_700_Host_Parameters *hostdata
                = (struct NCR_700_Host_Parameters *)host->hostdata[0];

#if 1
        /* sanity check the register */
        BUG_ON((reg & 0x3) != 0);
#endif

        bEBus ? iowrite32be(value, hostdata->base + reg): 
                iowrite32(value, hostdata->base + reg);
}

#endif