/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * ibtf_util.c
 *
 * This file contains the IBTF module's helper/utility functions.
 * - IBTF logging support
 */

#include <sys/ib/ibtl/impl/ibtl.h>

static char ibtf_util[] = "ibtl_util";

/* Function Prototypes */
static void     ibtf_clear_print_buf();

/*
 * Print Buffer protected by mutex for debug stuff. The mutex also
 * ensures serializing debug messages.
 */
static kmutex_t ibtf_print_mutex;
static char     ibtf_print_buf[IBTL_PRINT_BUF_LEN];

/*
 * Debug Stuff.
 */
uint_t  ibtf_errlevel = IBTF_LOG_L5;
uint_t  ibgen_errlevel = IBTF_LOG_L2;
uint_t  ibtl_errlevel = IBTF_LOG_L2;
uint_t  ibcm_errlevel = IBTF_LOG_L2;
uint_t  ibdm_errlevel = IBTF_LOG_L2;
uint_t  ibnex_errlevel = IBTF_LOG_L2;

#define IBTF_DEBUG_SIZE_EXTRA_ALLOC     8
#define IBTF_MIN_DEBUG_BUF_SIZE         0x1000
#ifdef  DEBUG
#define IBTF_DEBUG_BUF_SIZE             0x10000
#else
#define IBTF_DEBUG_BUF_SIZE             0x2000
#endif  /* DEBUG */

int     ibtf_suppress_dprintf;          /* Suppress debug printing */
int     ibtf_buffer_dprintf = 1;        /* Use a debug print buffer */
int     ibtf_debug_buf_size = IBTF_DEBUG_BUF_SIZE; /* Sz of Debug buf */
int     ibtf_allow_intr_msgs = 0;       /* log "intr" messages */
char    *ibtf_debug_buf = NULL;         /* The Debug Buf */
char    *ibtf_buf_sptr, *ibtf_buf_eptr; /* debug buffer temp pointer */
int     ibtf_clear_debug_buf_flag = 0;  /* Clear debug buffer */
_NOTE(SCHEME_PROTECTS_DATA("inconsistency OK", ibtf_debug_buf_size))

longlong_t ibtl_ib2usec_tbl[64];        /* time conversion table */
_NOTE(SCHEME_PROTECTS_DATA("inconsistency OK", ibtl_ib2usec_tbl))

_NOTE(MUTEX_PROTECTS_DATA(ibtf_print_mutex, ibtf_buf_sptr ibtf_buf_eptr))

/*
 * Function:
 *      ibtl_ib2usec_init
 * Input:
 *      none
 * Output:
 *      none
 * Returns:
 *      none
 * Description:
 *      Initialize ibtl_ib2usec_tbl[64] for use by ibt_usec2ib and ibt_ib2usec.
 */
void
ibtl_ib2usec_init(void)
{
        int i;

        for (i = 0; i < 64; i++) {
                if (i < 51) {           /* shift first to avoid underflow */
                        ibtl_ib2usec_tbl[i] = ((1LL << i) << 12LL) / 1000LL;
                } else if (i < 61) {    /* divide first to avoid overflow */
                        ibtl_ib2usec_tbl[i] = ((1LL << i) / 1000LL) << 12LL;
                } else {                /* max'ed out, so use MAX LONGLONG */
                        ibtl_ib2usec_tbl[i] = 0x7FFFFFFFFFFFFFFFLL;
                }
#if !defined(_LP64)
                if (ibtl_ib2usec_tbl[i] > LONG_MAX)
                        ibtl_ib2usec_tbl[i] = LONG_MAX;
#endif
        }
}

/*
 * Function:
 *      ibt_usec2ib
 * Input:
 *      time_val - Time in microsecs.
 * Output:
 *      none
 * Returns:
 *      Nearest IB Timeout Exponent value.
 * Description:
 *      This function converts the standard input time in microseconds to
 *      IB's 6 bits of timeout exponent, calculated based on
 *      time = 4.096us * 2 ^ exp.  This is done by searching through
 *      the ibtl_ib2usec_tbl for the closest value >= time_val.
 */
ib_time_t
ibt_usec2ib(clock_t time_val)
{
        int i;

        IBTF_DPRINTF_L3(ibtf_util, "ibt_usec2ib(%ld)", time_val);

        /* First, leap through the table by 4 entries at a time */
        for (i = 0; (i + 4) < 64 && ibtl_ib2usec_tbl[i + 4] < time_val; i += 4)
                ;
        /* Find the return value; it's now between i and i + 4, inclusive */
        while (ibtl_ib2usec_tbl[i] < time_val)
                i++;
        return (i);
}


/*
 * Function:
 *      ibt_ib2usec
 * Input:
 *      ib_time    - IB Timeout Exponent value.
 * Output:
 *      none
 * Returns:
 *      Standard Time is microseconds.
 * Description:
 *      This function converts the input IB timeout exponent (6 bits) to
 *      standard time in microseconds, calculated based on
 *      time = 4.096us * 2 ^ exp.
 *      This is implemented as a simple index into ibtl_ib2usec_tbl[].
 */
clock_t
ibt_ib2usec(ib_time_t ib_time)
{
        IBTF_DPRINTF_L3(ibtf_util, "ibt_ib2usec(%d)", ib_time);

        return ((clock_t)ibtl_ib2usec_tbl[ib_time & IB_TIME_EXP_MASK]);
}


/* IBTF logging init */
void
ibtl_logging_initialization()
{
        boolean_t flag = B_FALSE;

        IBTF_DPRINTF_L3(ibtf_util, "ibtl_logging_initialization:");

        mutex_init(&ibtf_print_mutex, NULL, MUTEX_DRIVER, NULL);
        mutex_enter(&ibtf_print_mutex);

        if (ibtf_debug_buf_size <= IBTF_DEBUG_SIZE_EXTRA_ALLOC) {
                ibtf_debug_buf_size = IBTF_MIN_DEBUG_BUF_SIZE;
                flag = B_TRUE;
        }

        /* if it is less that IBTF_MIN_DEBUG_BUF_SIZE, adjust it */
        ibtf_debug_buf_size = max(IBTF_MIN_DEBUG_BUF_SIZE,
            ibtf_debug_buf_size);

        ibtf_debug_buf = (char *)kmem_alloc(ibtf_debug_buf_size, KM_SLEEP);
        ibtf_clear_print_buf();
        mutex_exit(&ibtf_print_mutex);

        if (flag == B_TRUE) {
                IBTF_DPRINTF_L2(ibtf_util, "ibtf_debug_buf_size was too small "
                    "%x, adjusted to %x", ibtf_debug_buf_size,
                    IBTF_MIN_DEBUG_BUF_SIZE);
        }
}


/* IBTF logging destroy */
void
ibtl_logging_destroy()
{
        IBTF_DPRINTF_L3(ibtf_util, "ibtl_logging_destroy");

        mutex_enter(&ibtf_print_mutex);
        if (ibtf_debug_buf) {
                kmem_free(ibtf_debug_buf, ibtf_debug_buf_size);
                ibtf_debug_buf = NULL;
        }
        mutex_exit(&ibtf_print_mutex);
        mutex_destroy(&ibtf_print_mutex);
}


/*
 * debug, log, and console message handling
 */

/*
 * clear the IBTF trace buffer
 */
static void
ibtf_clear_print_buf()
{
        ASSERT(MUTEX_HELD(&ibtf_print_mutex));
        if (ibtf_debug_buf) {
                ibtf_buf_sptr = ibtf_debug_buf;
                ibtf_buf_eptr = ibtf_debug_buf + ibtf_debug_buf_size -
                    IBTF_DEBUG_SIZE_EXTRA_ALLOC;

                bzero(ibtf_debug_buf, ibtf_debug_buf_size);
        }
}


static void
ibtf_vlog(char *name, uint_t level, char *fmt, va_list ap)
{
        char    *label = (name == NULL) ? "ibtl" : name;
        char    *msg_ptr;
        size_t  len;

        mutex_enter(&ibtf_print_mutex);

        /* if not using logging scheme; quit */
        if (ibtf_suppress_dprintf || (ibtf_debug_buf == NULL)) {
                mutex_exit(&ibtf_print_mutex);
                return;
        }

        /* if level doesn't match, we are done */
        if ((level < IBTF_LOG_L0) || (level > IBTF_LOG_LINTR)) {
                mutex_exit(&ibtf_print_mutex);
                return;
        }

        /* If user requests to clear debug buffer, go ahead */
        if (ibtf_clear_debug_buf_flag != 0) {
                ibtf_clear_print_buf();
                ibtf_clear_debug_buf_flag = 0;
        }

        /*
         * Check if we have a valid buf size?
         * Suppress logging to ibtf_buffer if so.
         */
        if (ibtf_debug_buf_size <= 0) {
                ibtf_buffer_dprintf = 0;
        }

        /*
         * put "label" into the buffer
         */
        len = snprintf(ibtf_print_buf, IBTL_DRVNAME_LEN, "%s:\t", label);

        msg_ptr = ibtf_print_buf + len;
        len += vsnprintf(msg_ptr, IBTL_PRINT_BUF_LEN - len - 2, fmt, ap);

        len = min(len, IBTL_PRINT_BUF_LEN - 2);
        ASSERT(len == strlen(ibtf_print_buf));
        ibtf_print_buf[len++] = '\n';
        ibtf_print_buf[len] = '\0';

        /*
         * stuff the message in the debug buf
         */
        if (ibtf_buffer_dprintf) {

                /*
                 * overwrite >>>> that might be over the end of the
                 * the buffer
                 */
                *ibtf_buf_sptr = '\0';

                if (ibtf_buf_sptr + len > ibtf_buf_eptr) {
                        size_t left = ibtf_buf_eptr - ibtf_buf_sptr;

                        bcopy((caddr_t)ibtf_print_buf,
                            (caddr_t)ibtf_buf_sptr, left);
                        bcopy((caddr_t)ibtf_print_buf + left,
                            (caddr_t)ibtf_debug_buf, len - left);
                        ibtf_buf_sptr = ibtf_debug_buf + len - left;
                } else {
                        bcopy((caddr_t)ibtf_print_buf, ibtf_buf_sptr, len);
                        ibtf_buf_sptr += len;
                }

                /* add marker */
                (void) sprintf(ibtf_buf_sptr, ">>>>");
        }

        /*
         * LINTR, L5-L2 message may go to the ibtf_debug_buf
         * L1 messages will go to the log buf in non-debug kernels and
         * to console and log buf in debug kernels
         * L0 messages are warnings and will go to console and log buf
         */
        switch (level) {
        case IBTF_LOG_LINTR:
        case IBTF_LOG_L5:
        case IBTF_LOG_L4:
        case IBTF_LOG_L3:
        case IBTF_LOG_L2:
                if (!ibtf_buffer_dprintf) {
                        cmn_err(CE_CONT, "^%s", ibtf_print_buf);
                }
                break;
        case IBTF_LOG_L1:
#ifdef DEBUG
                cmn_err(CE_CONT, "%s", ibtf_print_buf);
#else
                if (!ibtf_buffer_dprintf) {
                        cmn_err(CE_CONT, "^%s", ibtf_print_buf);
                }
#endif
                break;
        case IBTF_LOG_L0:
                /* Strip the "\n" added earlier */
                if (ibtf_print_buf[len - 1] == '\n') {
                        ibtf_print_buf[len - 1] = '\0';
                }
                if (msg_ptr[len - 1] == '\n') {
                        msg_ptr[len - 1] = '\0';
                }
                cmn_err(CE_WARN, ibtf_print_buf);
                break;
        }

        mutex_exit(&ibtf_print_mutex);
}


void
ibtl_dprintf_intr(char *name, char *fmt, ...)
{
        va_list ap;

        /* only log messages if "ibtf_allow_intr_msgs" is set */
        if (!ibtf_allow_intr_msgs)
                return;

        va_start(ap, fmt);
        ibtf_vlog(name, IBTF_LOG_LINTR, fmt, ap);
        va_end(ap);
}


/*
 * Check individual subsystem err levels
 */
#define IBTL_CHECK_ERR_LEVEL(level)                     \
        if (strncmp(name, "ibgen", 5) == 0) {           \
                if (ibgen_errlevel < level)             \
                        return;                         \
        } else if (strncmp(name, "ibtl", 4) == 0) {     \
                if (ibtl_errlevel < level)              \
                        return;                         \
        } else if (strncmp(name, "ibcm", 4) == 0) {     \
                if (ibcm_errlevel < level)              \
                        return;                         \
        } else if (strncmp(name, "ibdm", 4) == 0) {     \
                if (ibdm_errlevel < level)              \
                        return;                         \
        } else if (strncmp(name, "ibnex", 5) == 0) {    \
                if (ibnex_errlevel < level)             \
                        return;                         \
        }

void
ibtl_dprintf5(char *name, char *fmt, ...)
{
        va_list ap;

        /* check if global errlevel matches or not */
        if (ibtf_errlevel < IBTF_LOG_L5)
                return;

        IBTL_CHECK_ERR_LEVEL(IBTF_LOG_L5);

        va_start(ap, fmt);
        ibtf_vlog(name, IBTF_LOG_L5, fmt, ap);
        va_end(ap);
}

void
ibtl_dprintf4(char *name, char *fmt, ...)
{
        va_list ap;

        /* check if global errlevel matches or not */
        if (ibtf_errlevel < IBTF_LOG_L4)
                return;

        IBTL_CHECK_ERR_LEVEL(IBTF_LOG_L4);

        va_start(ap, fmt);
        ibtf_vlog(name, IBTF_LOG_L4, fmt, ap);
        va_end(ap);
}


void
ibtl_dprintf3(char *name, char *fmt, ...)
{
        va_list ap;

        /* check if global errlevel matches or not */
        if (ibtf_errlevel < IBTF_LOG_L3)
                return;

        IBTL_CHECK_ERR_LEVEL(IBTF_LOG_L3);

        va_start(ap, fmt);
        ibtf_vlog(name, IBTF_LOG_L3, fmt, ap);
        va_end(ap);
}


void
ibtl_dprintf2(char *name, char *fmt, ...)
{
        va_list ap;

        /* check if global errlevel matches or not */
        if (ibtf_errlevel < IBTF_LOG_L2)
                return;

        IBTL_CHECK_ERR_LEVEL(IBTF_LOG_L2);

        va_start(ap, fmt);
        ibtf_vlog(name, IBTF_LOG_L2, fmt, ap);
        va_end(ap);
}


void
ibtl_dprintf1(char *name, char *fmt, ...)
{
        va_list ap;

        /* check if global errlevel matches or not */
        if (ibtf_errlevel < IBTF_LOG_L1)
                return;

        va_start(ap, fmt);
        ibtf_vlog(name, IBTF_LOG_L1, fmt, ap);
        va_end(ap);
}


/*
 * Function:
 *      ibtf_dprintf0
 * Input:
 *      name    - Name of the subsystem generating the debug message
 *      fmt     - The message to be displayed.
 * Output:
 *      none
 * Returns:
 *      none
 * Description:
 *      A generic log function to display IBTF debug messages.
 */
void
ibtl_dprintf0(char *name, char *fmt, ...)
{
        va_list ap;

        va_start(ap, fmt);
        ibtf_vlog(name, IBTF_LOG_L0, fmt, ap);
        va_end(ap);
}