/*
 * (C) Copyright 2002-2007
 * Detlev Zundel, DENX Software Engineering, dzu@denx.de.
 *
 * Code used from linux/kernel/printk.c
 * Copyright (C) 1991, 1992  Linus Torvalds
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 *
 * Comments:
 *
 * After relocating the code, the environment variable "loglevel" is
 * copied to console_loglevel.  The functionality is similar to the
 * handling in the Linux kernel, i.e. messages logged with a priority
 * less than console_loglevel are also output to stdout.
 *
 * If you want messages with the default level (e.g. POST messages) to
 * appear on stdout also, make sure the environment variable
 * "loglevel" is set at boot time to a number higher than
 * default_message_loglevel below.
 */

/*
 * Logbuffer handling routines
 */

#include <common.h>
#include <command.h>
#include <devices.h>
#include <post.h>
#include <logbuff.h>

DECLARE_GLOBAL_DATA_PTR;

/* Local prototypes */
static void logbuff_putc (const char c);
static void logbuff_puts (const char *s);
static int logbuff_printk(const char *line);

static char buf[1024];

/* This combination will not print messages with the default loglevel */
static unsigned console_loglevel = 3;
static unsigned default_message_loglevel = 4;
static unsigned log_version = 1;
#ifdef CONFIG_ALT_LB_ADDR
static volatile logbuff_t *log;
#else
static logbuff_t *log;
#endif
static char *lbuf;

unsigned long __logbuffer_base(void)
{
        return CONFIG_SYS_SDRAM_BASE + gd->bd->bi_memsize - LOGBUFF_LEN;
}
unsigned long logbuffer_base (void) __attribute__((weak, alias("__logbuffer_base")));

void logbuff_init_ptrs (void)
{
        unsigned long tag, post_word;
        char *s;

#ifdef CONFIG_ALT_LB_ADDR
        log = (logbuff_t *)CONFIG_ALT_LH_ADDR;
        lbuf = (char *)CONFIG_ALT_LB_ADDR;
#else
        log = (logbuff_t *)(logbuffer_base ()) - 1;
        lbuf = (char *)log->buf;
#endif

        /* Set up log version */
        if ((s = getenv ("logversion")) != NULL)
                log_version = (int)simple_strtoul (s, NULL, 10);

        if (log_version == 2)
                tag = log->v2.tag;
        else
                tag = log->v1.tag;
        post_word = post_word_load();
#ifdef CONFIG_POST
        /* The post routines have setup the word so we can simply test it */
        if (tag != LOGBUFF_MAGIC || (post_word & POST_COLDBOOT)) {
                logbuff_reset ();
        }
#else
        /* No post routines, so we do our own checking                    */
        if (tag != LOGBUFF_MAGIC || post_word != LOGBUFF_MAGIC) {
                logbuff_reset ();
                post_word_store (LOGBUFF_MAGIC);
        }
#endif
        if (log_version == 2 && (long)log->v2.start > (long)log->v2.con)
                log->v2.start = log->v2.con;

        /* Initialize default loglevel if present */
        if ((s = getenv ("loglevel")) != NULL)
                console_loglevel = (int)simple_strtoul (s, NULL, 10);

        gd->flags |= GD_FLG_LOGINIT;
}

void logbuff_reset (void)
{
#ifndef CONFIG_ALT_LB_ADDR
        memset (log, 0, sizeof (logbuff_t));
#endif
        if (log_version == 2) {
                log->v2.tag = LOGBUFF_MAGIC;
#ifdef CONFIG_ALT_LB_ADDR
                log->v2.start = 0;
                log->v2.con = 0;
                log->v2.end = 0;
                log->v2.chars = 0;
#endif
        } else {
                log->v1.tag = LOGBUFF_MAGIC;
#ifdef CONFIG_ALT_LB_ADDR
                log->v1.dummy = 0;
                log->v1.start = 0;
                log->v1.size = 0;
                log->v1.chars = 0;
#endif
        }
}

int drv_logbuff_init (void)
{
        device_t logdev;
        int rc;

        /* Device initialization */
        memset (&logdev, 0, sizeof (logdev));

        strcpy (logdev.name, "logbuff");
        logdev.ext   = 0;                       /* No extensions */
        logdev.flags = DEV_FLAGS_OUTPUT;        /* Output only */
        logdev.putc  = logbuff_putc;            /* 'putc' function */
        logdev.puts  = logbuff_puts;            /* 'puts' function */

        rc = device_register (&logdev);

        return (rc == 0) ? 1 : rc;
}

static void logbuff_putc (const char c)
{
        char buf[2];
        buf[0] = c;
        buf[1] = '\0';
        logbuff_printk (buf);
}

static void logbuff_puts (const char *s)
{
        logbuff_printk (s);
}

void logbuff_log(char *msg)
{
        if ((gd->flags & GD_FLG_LOGINIT)) {
                logbuff_printk (msg);
        } else {
                /* Can happen only for pre-relocated errors as logging */
                /* at that stage should be disabled                    */
                puts (msg);
        }
}

/*
 * Subroutine:  do_log
 *
 * Description: Handler for 'log' command..
 *
 * Inputs:      argv[1] contains the subcommand
 *
 * Return:      None
 *
 */
int do_log (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
        char *s;
        unsigned long i, start, size;

        if (strcmp(argv[1],"append") == 0) {
                /* Log concatenation of all arguments separated by spaces */
                for (i=2; i<argc; i++) {
                        logbuff_printk (argv[i]);
                        logbuff_putc ((i<argc-1) ? ' ' : '\n');
                }
                return 0;
        }

        switch (argc) {

        case 2:
                if (strcmp(argv[1],"show") == 0) {
                        if (log_version == 2) {
                                start = log->v2.start;
                                size = log->v2.end - log->v2.start;
                        }
                        else {
                                start = log->v1.start;
                                size = log->v1.size;
                        }
                        for (i=0; i < (size&LOGBUFF_MASK); i++) {
                                s = lbuf+((start+i)&LOGBUFF_MASK);
                                putc (*s);
                        }
                        return 0;
                } else if (strcmp(argv[1],"reset") == 0) {
                        logbuff_reset ();
                        return 0;
                } else if (strcmp(argv[1],"info") == 0) {
                        printf ("Logbuffer   at  %08lx\n", (unsigned long)lbuf);
                        if (log_version == 2) {
                                printf ("log_start    =  %08lx\n", log->v2.start);
                                printf ("log_end      =  %08lx\n", log->v2.end);
                                printf ("logged_chars =  %08lx\n", log->v2.chars);
                        }
                        else {
                                printf ("log_start    =  %08lx\n", log->v1.start);
                                printf ("log_size     =  %08lx\n", log->v1.size);
                                printf ("logged_chars =  %08lx\n", log->v1.chars);
                        }
                        return 0;
                }
                printf ("Usage:\n%s\n", cmdtp->usage);
                return 1;

        default:
                printf ("Usage:\n%s\n", cmdtp->usage);
                return 1;
        }
}

U_BOOT_CMD(
        log,     255,   1,      do_log,
        "log     - manipulate logbuffer\n",
        "info   - show pointer details\n"
        "log reset  - clear contents\n"
        "log show   - show contents\n"
        "log append <msg> - append <msg> to the logbuffer\n"
);

static int logbuff_printk(const char *line)
{
        int i;
        char *msg, *p, *buf_end;
        int line_feed;
        static signed char msg_level = -1;

        strcpy (buf + 3, line);
        i = strlen (line);
        buf_end = buf + 3 + i;
        for (p = buf + 3; p < buf_end; p++) {
                msg = p;
                if (msg_level < 0) {
                        if (
                                p[0] != '<' ||
                                p[1] < '0' ||
                                p[1] > '7' ||
                                p[2] != '>'
                        ) {
                                p -= 3;
                                p[0] = '<';
                                p[1] = default_message_loglevel + '0';
                                p[2] = '>';
                        } else
                                msg += 3;
                        msg_level = p[1] - '0';
                }
                line_feed = 0;
                for (; p < buf_end; p++) {
                        if (log_version == 2) {
                                lbuf[log->v2.end & LOGBUFF_MASK] = *p;
                                log->v2.end++;
                                if (log->v2.end - log->v2.start > LOGBUFF_LEN)
                                        log->v2.start++;
                                log->v2.chars++;
                        }
                        else {
                                lbuf[(log->v1.start + log->v1.size) &
                                         LOGBUFF_MASK] = *p;
                                if (log->v1.size < LOGBUFF_LEN)
                                        log->v1.size++;
                                else
                                        log->v1.start++;
                                log->v1.chars++;
                        }
                        if (*p == '\n') {
                                line_feed = 1;
                                break;
                        }
                }
                if (msg_level < console_loglevel) {
                        printf("%s", msg);
                }
                if (line_feed)
                        msg_level = -1;
        }
        return i;
}