[people/ms/u-boot.git] / common / cmd_nvedit.c

/*
 * (C) Copyright 2000-2010
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Andreas Heppel <aheppel@sysgo.de>
 *
 * Copyright 2011 Freescale Semiconductor, Inc.
 *
 * 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
 */

/*
 * Support for persistent environment data
 *
 * The "environment" is stored on external storage as a list of '\0'
 * terminated "name=value" strings. The end of the list is marked by
 * a double '\0'. The environment is preceeded by a 32 bit CRC over
 * the data part and, in case of redundant environment, a byte of
 * flags.
 *
 * This linearized representation will also be used before
 * relocation, i. e. as long as we don't have a full C runtime
 * environment. After that, we use a hash table.
 */

#include <common.h>
#include <command.h>
#include <environment.h>
#include <search.h>
#include <errno.h>
#include <malloc.h>
#include <watchdog.h>
#include <serial.h>
#include <linux/stddef.h>
#include <asm/byteorder.h>
#if defined(CONFIG_CMD_NET)
#include <net.h>
#endif

DECLARE_GLOBAL_DATA_PTR;

#if     !defined(CONFIG_ENV_IS_IN_EEPROM)       && \
        !defined(CONFIG_ENV_IS_IN_FLASH)        && \
        !defined(CONFIG_ENV_IS_IN_DATAFLASH)    && \
        !defined(CONFIG_ENV_IS_IN_MMC)          && \
        !defined(CONFIG_ENV_IS_IN_FAT)          && \
        !defined(CONFIG_ENV_IS_IN_NAND)         && \
        !defined(CONFIG_ENV_IS_IN_NVRAM)        && \
        !defined(CONFIG_ENV_IS_IN_ONENAND)      && \
        !defined(CONFIG_ENV_IS_IN_SPI_FLASH)    && \
        !defined(CONFIG_ENV_IS_IN_REMOTE)       && \
        !defined(CONFIG_ENV_IS_NOWHERE)
# error Define one of CONFIG_ENV_IS_IN_{EEPROM|FLASH|DATAFLASH|ONENAND|\
SPI_FLASH|NVRAM|MMC|FAT|REMOTE} or CONFIG_ENV_IS_NOWHERE
#endif

/*
 * Maximum expected input data size for import command
 */
#define MAX_ENV_SIZE    (1 << 20)       /* 1 MiB */

ulong load_addr = CONFIG_SYS_LOAD_ADDR; /* Default Load Address */
ulong save_addr;                        /* Default Save Address */
ulong save_size;                        /* Default Save Size (in bytes) */

/*
 * Table with supported baudrates (defined in config_xyz.h)
 */
static const unsigned long baudrate_table[] = CONFIG_SYS_BAUDRATE_TABLE;
#define N_BAUDRATES (sizeof(baudrate_table) / sizeof(baudrate_table[0]))

/*
 * This variable is incremented on each do_env_set(), so it can
 * be used via get_env_id() as an indication, if the environment
 * has changed or not. So it is possible to reread an environment
 * variable only if the environment was changed ... done so for
 * example in NetInitLoop()
 */
static int env_id = 1;

int get_env_id(void)
{
        return env_id;
}

#ifndef CONFIG_SPL_BUILD
/*
 * Command interface: print one or all environment variables
 *
 * Returns 0 in case of error, or length of printed string
 */
static int env_print(char *name)
{
        char *res = NULL;
        size_t len;

        if (name) {             /* print a single name */
                ENTRY e, *ep;

                e.key = name;
                e.data = NULL;
                hsearch_r(e, FIND, &ep, &env_htab);
                if (ep == NULL)
                        return 0;
                len = printf("%s=%s\n", ep->key, ep->data);
                return len;
        }

        /* print whole list */
        len = hexport_r(&env_htab, '\n', &res, 0, 0, NULL);

        if (len > 0) {
                puts(res);
                free(res);
                return len;
        }

        /* should never happen */
        return 0;
}

int do_env_print (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        int i;
        int rcode = 0;

        if (argc == 1) {
                /* print all env vars */
                rcode = env_print(NULL);
                if (!rcode)
                        return 1;
                printf("\nEnvironment size: %d/%ld bytes\n",
                        rcode, (ulong)ENV_SIZE);
                return 0;
        }

        /* print selected env vars */
        for (i = 1; i < argc; ++i) {
                int rc = env_print(argv[i]);
                if (!rc) {
                        printf("## Error: \"%s\" not defined\n", argv[i]);
                        ++rcode;
                }
        }

        return rcode;
}

#ifdef CONFIG_CMD_GREPENV
static int do_env_grep(cmd_tbl_t *cmdtp, int flag,
                       int argc, char * const argv[])
{
        ENTRY *match;
        unsigned char matched[env_htab.size / 8];
        int rcode = 1, arg = 1, idx;

        if (argc < 2)
                return CMD_RET_USAGE;

        memset(matched, 0, env_htab.size / 8);

        while (arg <= argc) {
                idx = 0;
                while ((idx = hstrstr_r(argv[arg], idx, &match, &env_htab))) {
                        if (!(matched[idx / 8] & (1 << (idx & 7)))) {
                                puts(match->key);
                                puts("=");
                                puts(match->data);
                                puts("\n");
                        }
                        matched[idx / 8] |= 1 << (idx & 7);
                        rcode = 0;
                }
                arg++;
        }

        return rcode;
}
#endif
#endif /* CONFIG_SPL_BUILD */

/*
 * Perform consistency checking before setting, replacing, or deleting an
 * environment variable, then (if successful) apply the changes to internals so
 * to make them effective.  Code for this function was taken out of
 * _do_env_set(), which now calls it instead.
 * Also called as a callback function by himport_r().
 * Returns 0 in case of success, 1 in case of failure.
 * When (flag & H_FORCE) is set, do not print out any error message and force
 * overwriting of write-once variables.
 */

int env_check_apply(const char *name, const char *oldval,
                        const char *newval, int flag)
{
        int   console = -1;

        /* Default value for NULL to protect string-manipulating functions */
        newval = newval ? : "";

        /* Check for console redirection */
        if (strcmp(name, "stdin") == 0)
                console = stdin;
        else if (strcmp(name, "stdout") == 0)
                console = stdout;
        else if (strcmp(name, "stderr") == 0)
                console = stderr;

        if (console != -1) {
                if ((newval == NULL) || (*newval == '\0')) {
                        /* We cannot delete stdin/stdout/stderr */
                        if ((flag & H_FORCE) == 0)
                                printf("Can't delete \"%s\"\n", name);
                        return 1;
                }

#ifdef CONFIG_CONSOLE_MUX
                if (iomux_doenv(console, newval))
                        return 1;
#else
                /* Try assigning specified device */
                if (console_assign(console, newval) < 0)
                        return 1;

#ifdef CONFIG_SERIAL_MULTI
                if (serial_assign(newval) < 0)
                        return 1;
#endif
#endif /* CONFIG_CONSOLE_MUX */
        }

        /*
         * Some variables like "ethaddr" and "serial#" can be set only once and
         * cannot be deleted, unless CONFIG_ENV_OVERWRITE is defined.
         */
#ifndef CONFIG_ENV_OVERWRITE
        if (oldval != NULL &&                   /* variable exists */
                (flag & H_FORCE) == 0) {        /* and we are not forced */
                if (strcmp(name, "serial#") == 0 ||
                    (strcmp(name, "ethaddr") == 0
#if defined(CONFIG_OVERWRITE_ETHADDR_ONCE) && defined(CONFIG_ETHADDR)
                     && strcmp(oldval, __stringify(CONFIG_ETHADDR)) != 0
#endif  /* CONFIG_OVERWRITE_ETHADDR_ONCE && CONFIG_ETHADDR */
                        )) {
                        printf("Can't overwrite \"%s\"\n", name);
                        return 1;
                }
        }
#endif
        /*
         * When we change baudrate, or we are doing an env default -a
         * (which will erase all variables prior to calling this),
         * we want the baudrate to actually change - for real.
         */
        if (oldval != NULL ||                   /* variable exists */
                (flag & H_NOCLEAR) == 0) {      /* or env is clear */
                /*
                 * Switch to new baudrate if new baudrate is supported
                 */
                if (strcmp(name, "baudrate") == 0) {
                        int baudrate = simple_strtoul(newval, NULL, 10);
                        int i;
                        for (i = 0; i < N_BAUDRATES; ++i) {
                                if (baudrate == baudrate_table[i])
                                        break;
                        }
                        if (i == N_BAUDRATES) {
                                if ((flag & H_FORCE) == 0)
                                        printf("## Baudrate %d bps not "
                                                "supported\n", baudrate);
                                return 1;
                        }
                        if (gd->baudrate == baudrate) {
                                /* If unchanged, we just say it's OK */
                                return 0;
                        }
                        printf("## Switch baudrate to %d bps and"
                                "press ENTER ...\n", baudrate);
                        udelay(50000);
                        gd->baudrate = baudrate;
#if defined(CONFIG_PPC) || defined(CONFIG_MCF52x2)
                        gd->bd->bi_baudrate = baudrate;
#endif

                        serial_setbrg();
                        udelay(50000);
                        while (getc() != '\r')
                                ;
                }
        }

        /*
         * Some variables should be updated when the corresponding
         * entry in the environment is changed
         */
        if (strcmp(name, "loadaddr") == 0) {
                load_addr = simple_strtoul(newval, NULL, 16);
                return 0;
        }
#if defined(CONFIG_CMD_NET)
        else if (strcmp(name, "bootfile") == 0) {
                copy_filename(BootFile, newval, sizeof(BootFile));
                return 0;
        }
#endif
        return 0;
}

/*
 * Set a new environment variable,
 * or replace or delete an existing one.
*/
int _do_env_set(int flag, int argc, char * const argv[])
{
        int   i, len;
        char  *name, *value, *s;
        ENTRY e, *ep;

        name = argv[1];
        value = argv[2];

        if (strchr(name, '=')) {
                printf("## Error: illegal character '='"
                       "in variable name \"%s\"\n", name);
                return 1;
        }

        env_id++;
        /*
         * search if variable with this name already exists
         */
        e.key = name;
        e.data = NULL;
        hsearch_r(e, FIND, &ep, &env_htab);

        /*
         * Perform requested checks. Notice how since we are overwriting
         * a single variable, we need to set H_NOCLEAR
         */
        if (env_check_apply(name, ep ? ep->data : NULL, value, H_NOCLEAR)) {
                debug("check function did not approve, refusing\n");
                return 1;
        }

        /* Delete only ? */
        if (argc < 3 || argv[2] == NULL) {
                int rc = hdelete_r(name, &env_htab, 0);
                return !rc;
        }

        /*
         * Insert / replace new value
         */
        for (i = 2, len = 0; i < argc; ++i)
                len += strlen(argv[i]) + 1;

        value = malloc(len);
        if (value == NULL) {
                printf("## Can't malloc %d bytes\n", len);
                return 1;
        }
        for (i = 2, s = value; i < argc; ++i) {
                char *v = argv[i];

                while ((*s++ = *v++) != '\0')
                        ;
                *(s - 1) = ' ';
        }
        if (s != value)
                *--s = '\0';

        e.key   = name;
        e.data  = value;
        hsearch_r(e, ENTER, &ep, &env_htab);
        free(value);
        if (!ep) {
                printf("## Error inserting \"%s\" variable, errno=%d\n",
                        name, errno);
                return 1;
        }

        return 0;
}

int setenv(const char *varname, const char *varvalue)
{
        const char * const argv[4] = { "setenv", varname, varvalue, NULL };

        if (varvalue == NULL || varvalue[0] == '\0')
                return _do_env_set(0, 2, (char * const *)argv);
        else
                return _do_env_set(0, 3, (char * const *)argv);
}

/**
 * Set an environment variable to an integer value
 *
 * @param varname       Environmet variable to set
 * @param value         Value to set it to
 * @return 0 if ok, 1 on error
 */
int setenv_ulong(const char *varname, ulong value)
{
        /* TODO: this should be unsigned */
        char *str = simple_itoa(value);

        return setenv(varname, str);
}

/**
 * Set an environment variable to an address in hex
 *
 * @param varname       Environmet variable to set
 * @param addr          Value to set it to
 * @return 0 if ok, 1 on error
 */
int setenv_addr(const char *varname, const void *addr)
{
        char str[17];

        sprintf(str, "%lx", (uintptr_t)addr);
        return setenv(varname, str);
}

#ifndef CONFIG_SPL_BUILD
int do_env_set(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        if (argc < 2)
                return CMD_RET_USAGE;

        return _do_env_set(flag, argc, argv);
}

/*
 * Prompt for environment variable
 */
#if defined(CONFIG_CMD_ASKENV)
int do_env_ask(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        char message[CONFIG_SYS_CBSIZE];
        int size = CONFIG_SYS_CBSIZE - 1;
        int i, len, pos;
        char *local_args[4];

        local_args[0] = argv[0];
        local_args[1] = argv[1];
        local_args[2] = NULL;
        local_args[3] = NULL;

        /* Check the syntax */
        switch (argc) {
        case 1:
                return CMD_RET_USAGE;

        case 2:         /* env_ask envname */
                sprintf(message, "Please enter '%s':", argv[1]);
                break;

        case 3:         /* env_ask envname size */
                sprintf(message, "Please enter '%s':", argv[1]);
                size = simple_strtoul(argv[2], NULL, 10);
                break;

        default:        /* env_ask envname message1 ... messagen size */
                for (i = 2, pos = 0; i < argc - 1; i++) {
                        if (pos)
                                message[pos++] = ' ';

                        strcpy(message + pos, argv[i]);
                        pos += strlen(argv[i]);
                }

                message[pos] = '\0';
                size = simple_strtoul(argv[argc - 1], NULL, 10);
                break;
        }

        if (size >= CONFIG_SYS_CBSIZE)
                size = CONFIG_SYS_CBSIZE - 1;

        if (size <= 0)
                return 1;

        /* prompt for input */
        len = readline(message);

        if (size < len)
                console_buffer[size] = '\0';

        len = 2;
        if (console_buffer[0] != '\0') {
                local_args[2] = console_buffer;
                len = 3;
        }

        /* Continue calling setenv code */
        return _do_env_set(flag, len, local_args);
}
#endif

/*
 * Interactively edit an environment variable
 */
#if defined(CONFIG_CMD_EDITENV)
int do_env_edit(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        char buffer[CONFIG_SYS_CBSIZE];
        char *init_val;

        if (argc < 2)
                return CMD_RET_USAGE;

        /* Set read buffer to initial value or empty sting */
        init_val = getenv(argv[1]);
        if (init_val)
                sprintf(buffer, "%s", init_val);
        else
                buffer[0] = '\0';

        readline_into_buffer("edit: ", buffer, 0);

        return setenv(argv[1], buffer);
}
#endif /* CONFIG_CMD_EDITENV */
#endif /* CONFIG_SPL_BUILD */

/*
 * Look up variable from environment,
 * return address of storage for that variable,
 * or NULL if not found
 */
char *getenv(const char *name)
{
        if (gd->flags & GD_FLG_ENV_READY) { /* after import into hashtable */
                ENTRY e, *ep;

                WATCHDOG_RESET();

                e.key   = name;
                e.data  = NULL;
                hsearch_r(e, FIND, &ep, &env_htab);

                return ep ? ep->data : NULL;
        }

        /* restricted capabilities before import */
        if (getenv_f(name, (char *)(gd->env_buf), sizeof(gd->env_buf)) > 0)
                return (char *)(gd->env_buf);

        return NULL;
}

/*
 * Look up variable from environment for restricted C runtime env.
 */
int getenv_f(const char *name, char *buf, unsigned len)
{
        int i, nxt;

        for (i = 0; env_get_char(i) != '\0'; i = nxt + 1) {
                int val, n;

                for (nxt = i; env_get_char(nxt) != '\0'; ++nxt) {
                        if (nxt >= CONFIG_ENV_SIZE)
                                return -1;
                }

                val = envmatch((uchar *)name, i);
                if (val < 0)
                        continue;

                /* found; copy out */
                for (n = 0; n < len; ++n, ++buf) {
                        *buf = env_get_char(val++);
                        if (*buf == '\0')
                                return n;
                }

                if (n)
                        *--buf = '\0';

                printf("env_buf [%d bytes] too small for value of \"%s\"\n",
                        len, name);

                return n;
        }

        return -1;
}

/**
 * Decode the integer value of an environment variable and return it.
 *
 * @param name          Name of environemnt variable
 * @param base          Number base to use (normally 10, or 16 for hex)
 * @param default_val   Default value to return if the variable is not
 *                      found
 * @return the decoded value, or default_val if not found
 */
ulong getenv_ulong(const char *name, int base, ulong default_val)
{
        /*
         * We can use getenv() here, even before relocation, since the
         * environment variable value is an integer and thus short.
         */
        const char *str = getenv(name);

        return str ? simple_strtoul(str, NULL, base) : default_val;
}

#ifndef CONFIG_SPL_BUILD
#if defined(CONFIG_CMD_SAVEENV) && !defined(CONFIG_ENV_IS_NOWHERE)
int do_env_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        printf("Saving Environment to %s...\n", env_name_spec);

        return saveenv() ? 1 : 0;
}

U_BOOT_CMD(
        saveenv, 1, 0,  do_env_save,
        "save environment variables to persistent storage",
        ""
);
#endif
#endif /* CONFIG_SPL_BUILD */


/*
 * Match a name / name=value pair
 *
 * s1 is either a simple 'name', or a 'name=value' pair.
 * i2 is the environment index for a 'name2=value2' pair.
 * If the names match, return the index for the value2, else -1.
 */
int envmatch(uchar *s1, int i2)
{
        while (*s1 == env_get_char(i2++))
                if (*s1++ == '=')
                        return i2;

        if (*s1 == '\0' && env_get_char(i2-1) == '=')
                return i2;

        return -1;
}

#ifndef CONFIG_SPL_BUILD
static int do_env_default(cmd_tbl_t *cmdtp, int __flag,
                          int argc, char * const argv[])
{
        int all = 0, flag = 0;

        debug("Initial value for argc=%d\n", argc);
        while (--argc > 0 && **++argv == '-') {
                char *arg = *argv;

                while (*++arg) {
                        switch (*arg) {
                        case 'a':               /* default all */
                                all = 1;
                                break;
                        case 'f':               /* force */
                                flag |= H_FORCE;
                                break;
                        default:
                                return cmd_usage(cmdtp);
                        }
                }
        }
        debug("Final value for argc=%d\n", argc);
        if (all && (argc == 0)) {
                /* Reset the whole environment */
                set_default_env("## Resetting to default environment\n");
                return 0;
        }
        if (!all && (argc > 0)) {
                /* Reset individual variables */
                set_default_vars(argc, argv);
                return 0;
        }

        return cmd_usage(cmdtp);
}

static int do_env_delete(cmd_tbl_t *cmdtp, int flag,
                         int argc, char * const argv[])
{
        printf("Not implemented yet\n");
        return 0;
}

#ifdef CONFIG_CMD_EXPORTENV
/*
 * env export [-t | -b | -c] [-s size] addr [var ...]
 *      -t:     export as text format; if size is given, data will be
 *              padded with '\0' bytes; if not, one terminating '\0'
 *              will be added (which is included in the "filesize"
 *              setting so you can for exmple copy this to flash and
 *              keep the termination).
 *      -b:     export as binary format (name=value pairs separated by
 *              '\0', list end marked by double "\0\0")
 *      -c:     export as checksum protected environment format as
 *              used for example by "saveenv" command
 *      -s size:
 *              size of output buffer
 *      addr:   memory address where environment gets stored
 *      var...  List of variable names that get included into the
 *              export. Without arguments, the whole environment gets
 *              exported.
 *
 * With "-c" and size is NOT given, then the export command will
 * format the data as currently used for the persistent storage,
 * i. e. it will use CONFIG_ENV_SECT_SIZE as output block size and
 * prepend a valid CRC32 checksum and, in case of resundant
 * environment, a "current" redundancy flag. If size is given, this
 * value will be used instead of CONFIG_ENV_SECT_SIZE; again, CRC32
 * checksum and redundancy flag will be inserted.
 *
 * With "-b" and "-t", always only the real data (including a
 * terminating '\0' byte) will be written; here the optional size
 * argument will be used to make sure not to overflow the user
 * provided buffer; the command will abort if the size is not
 * sufficient. Any remainign space will be '\0' padded.
 *
 * On successful return, the variable "filesize" will be set.
 * Note that filesize includes the trailing/terminating '\0' byte(s).
 *
 * Usage szenario:  create a text snapshot/backup of the current settings:
 *
 *      => env export -t 100000
 *      => era ${backup_addr} +${filesize}
 *      => cp.b 100000 ${backup_addr} ${filesize}
 *
 * Re-import this snapshot, deleting all other settings:
 *
 *      => env import -d -t ${backup_addr}
 */
static int do_env_export(cmd_tbl_t *cmdtp, int flag,
                         int argc, char * const argv[])
{
        char    buf[32];
        char    *addr, *cmd, *res;
        size_t  size = 0;
        ssize_t len;
        env_t   *envp;
        char    sep = '\n';
        int     chk = 0;
        int     fmt = 0;

        cmd = *argv;

        while (--argc > 0 && **++argv == '-') {
                char *arg = *argv;
                while (*++arg) {
                        switch (*arg) {
                        case 'b':               /* raw binary format */
                                if (fmt++)
                                        goto sep_err;
                                sep = '\0';
                                break;
                        case 'c':               /* external checksum format */
                                if (fmt++)
                                        goto sep_err;
                                sep = '\0';
                                chk = 1;
                                break;
                        case 's':               /* size given */
                                if (--argc <= 0)
                                        return cmd_usage(cmdtp);
                                size = simple_strtoul(*++argv, NULL, 16);
                                goto NXTARG;
                        case 't':               /* text format */
                                if (fmt++)
                                        goto sep_err;
                                sep = '\n';
                                break;
                        default:
                                return CMD_RET_USAGE;
                        }
                }
NXTARG:         ;
        }

        if (argc < 1)
                return CMD_RET_USAGE;

        addr = (char *)simple_strtoul(argv[0], NULL, 16);

        if (size)
                memset(addr, '\0', size);

        argc--;
        argv++;

        if (sep) {              /* export as text file */
                len = hexport_r(&env_htab, sep, &addr, size, argc, argv);
                if (len < 0) {
                        error("Cannot export environment: errno = %d\n", errno);
                        return 1;
                }
                sprintf(buf, "%zX", (size_t)len);
                setenv("filesize", buf);

                return 0;
        }

        envp = (env_t *)addr;

        if (chk)                /* export as checksum protected block */
                res = (char *)envp->data;
        else                    /* export as raw binary data */
                res = addr;

        len = hexport_r(&env_htab, '\0', &res, ENV_SIZE, argc, argv);
        if (len < 0) {
                error("Cannot export environment: errno = %d\n", errno);
                return 1;
        }

        if (chk) {
                envp->crc = crc32(0, envp->data, ENV_SIZE);
#ifdef CONFIG_ENV_ADDR_REDUND
                envp->flags = ACTIVE_FLAG;
#endif
        }
        sprintf(buf, "%zX", (size_t)(len + offsetof(env_t, data)));
        setenv("filesize", buf);

        return 0;

sep_err:
        printf("## %s: only one of \"-b\", \"-c\" or \"-t\" allowed\n", cmd);
        return 1;
}
#endif

#ifdef CONFIG_CMD_IMPORTENV
/*
 * env import [-d] [-t | -b | -c] addr [size]
 *      -d:     delete existing environment before importing;
 *              otherwise overwrite / append to existion definitions
 *      -t:     assume text format; either "size" must be given or the
 *              text data must be '\0' terminated
 *      -b:     assume binary format ('\0' separated, "\0\0" terminated)
 *      -c:     assume checksum protected environment format
 *      addr:   memory address to read from
 *      size:   length of input data; if missing, proper '\0'
 *              termination is mandatory
 */
static int do_env_import(cmd_tbl_t *cmdtp, int flag,
                         int argc, char * const argv[])
{
        char    *cmd, *addr;
        char    sep = '\n';
        int     chk = 0;
        int     fmt = 0;
        int     del = 0;
        size_t  size;

        cmd = *argv;

        while (--argc > 0 && **++argv == '-') {
                char *arg = *argv;
                while (*++arg) {
                        switch (*arg) {
                        case 'b':               /* raw binary format */
                                if (fmt++)
                                        goto sep_err;
                                sep = '\0';
                                break;
                        case 'c':               /* external checksum format */
                                if (fmt++)
                                        goto sep_err;
                                sep = '\0';
                                chk = 1;
                                break;
                        case 't':               /* text format */
                                if (fmt++)
                                        goto sep_err;
                                sep = '\n';
                                break;
                        case 'd':
                                del = 1;
                                break;
                        default:
                                return CMD_RET_USAGE;
                        }
                }
        }

        if (argc < 1)
                return CMD_RET_USAGE;

        if (!fmt)
                printf("## Warning: defaulting to text format\n");

        addr = (char *)simple_strtoul(argv[0], NULL, 16);

        if (argc == 2) {
                size = simple_strtoul(argv[1], NULL, 16);
        } else {
                char *s = addr;

                size = 0;

                while (size < MAX_ENV_SIZE) {
                        if ((*s == sep) && (*(s+1) == '\0'))
                                break;
                        ++s;
                        ++size;
                }
                if (size == MAX_ENV_SIZE) {
                        printf("## Warning: Input data exceeds %d bytes"
                                " - truncated\n", MAX_ENV_SIZE);
                }
                size += 2;
                printf("## Info: input data size = %zu = 0x%zX\n", size, size);
        }

        if (chk) {
                uint32_t crc;
                env_t *ep = (env_t *)addr;

                size -= offsetof(env_t, data);
                memcpy(&crc, &ep->crc, sizeof(crc));

                if (crc32(0, ep->data, size) != crc) {
                        puts("## Error: bad CRC, import failed\n");
                        return 1;
                }
                addr = (char *)ep->data;
        }

        if (himport_r(&env_htab, addr, size, sep, del ? 0 : H_NOCLEAR,
                        0, NULL, 0 /* do_apply */) == 0) {
                error("Environment import failed: errno = %d\n", errno);
                return 1;
        }
        gd->flags |= GD_FLG_ENV_READY;

        return 0;

sep_err:
        printf("## %s: only one of \"-b\", \"-c\" or \"-t\" allowed\n",
                cmd);
        return 1;
}
#endif

/*
 * New command line interface: "env" command with subcommands
 */
static cmd_tbl_t cmd_env_sub[] = {
#if defined(CONFIG_CMD_ASKENV)
        U_BOOT_CMD_MKENT(ask, CONFIG_SYS_MAXARGS, 1, do_env_ask, "", ""),
#endif
        U_BOOT_CMD_MKENT(default, 1, 0, do_env_default, "", ""),
        U_BOOT_CMD_MKENT(delete, 2, 0, do_env_delete, "", ""),
#if defined(CONFIG_CMD_EDITENV)
        U_BOOT_CMD_MKENT(edit, 2, 0, do_env_edit, "", ""),
#endif
#if defined(CONFIG_CMD_EXPORTENV)
        U_BOOT_CMD_MKENT(export, 4, 0, do_env_export, "", ""),
#endif
#if defined(CONFIG_CMD_GREPENV)
        U_BOOT_CMD_MKENT(grep, CONFIG_SYS_MAXARGS, 1, do_env_grep, "", ""),
#endif
#if defined(CONFIG_CMD_IMPORTENV)
        U_BOOT_CMD_MKENT(import, 5, 0, do_env_import, "", ""),
#endif
        U_BOOT_CMD_MKENT(print, CONFIG_SYS_MAXARGS, 1, do_env_print, "", ""),
#if defined(CONFIG_CMD_RUN)
        U_BOOT_CMD_MKENT(run, CONFIG_SYS_MAXARGS, 1, do_run, "", ""),
#endif
#if defined(CONFIG_CMD_SAVEENV) && !defined(CONFIG_ENV_IS_NOWHERE)
        U_BOOT_CMD_MKENT(save, 1, 0, do_env_save, "", ""),
#endif
        U_BOOT_CMD_MKENT(set, CONFIG_SYS_MAXARGS, 0, do_env_set, "", ""),
};

#if defined(CONFIG_NEEDS_MANUAL_RELOC)
void env_reloc(void)
{
        fixup_cmdtable(cmd_env_sub, ARRAY_SIZE(cmd_env_sub));
}
#endif

static int do_env(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
        cmd_tbl_t *cp;

        if (argc < 2)
                return CMD_RET_USAGE;

        /* drop initial "env" arg */
        argc--;
        argv++;

        cp = find_cmd_tbl(argv[0], cmd_env_sub, ARRAY_SIZE(cmd_env_sub));

        if (cp)
                return cp->cmd(cmdtp, flag, argc, argv);

        return CMD_RET_USAGE;
}

U_BOOT_CMD(
        env, CONFIG_SYS_MAXARGS, 1, do_env,
        "environment handling commands",
#if defined(CONFIG_CMD_ASKENV)
        "ask name [message] [size] - ask for environment variable\nenv "
#endif
        "default [-f] -a - [forcibly] reset default environment\n"
        "env default [-f] var [...] - [forcibly] reset variable(s) to their default values\n"
#if defined(CONFIG_CMD_EDITENV)
        "env edit name - edit environment variable\n"
#endif
#if defined(CONFIG_CMD_EXPORTENV)
        "env export [-t | -b | -c] [-s size] addr [var ...] - export environment\n"
#endif
#if defined(CONFIG_CMD_GREPENV)
        "env grep string [...] - search environment\n"
#endif
#if defined(CONFIG_CMD_IMPORTENV)
        "env import [-d] [-t | -b | -c] addr [size] - import environment\n"
#endif
        "env print [name ...] - print environment\n"
#if defined(CONFIG_CMD_RUN)
        "env run var [...] - run commands in an environment variable\n"
#endif
#if defined(CONFIG_CMD_SAVEENV) && !defined(CONFIG_ENV_IS_NOWHERE)
        "env save - save environment\n"
#endif
        "env set [-f] name [arg ...]\n"
);

/*
 * Old command line interface, kept for compatibility
 */

#if defined(CONFIG_CMD_EDITENV)
U_BOOT_CMD_COMPLETE(
        editenv, 2, 0,  do_env_edit,
        "edit environment variable",
        "name\n"
        "    - edit environment variable 'name'",
        var_complete
);
#endif

U_BOOT_CMD_COMPLETE(
        printenv, CONFIG_SYS_MAXARGS, 1,        do_env_print,
        "print environment variables",
        "\n    - print values of all environment variables\n"
        "printenv name ...\n"
        "    - print value of environment variable 'name'",
        var_complete
);

#ifdef CONFIG_CMD_GREPENV
U_BOOT_CMD_COMPLETE(
        grepenv, CONFIG_SYS_MAXARGS, 0,  do_env_grep,
        "search environment variables",
        "string ...\n"
        "    - list environment name=value pairs matching 'string'",
        var_complete
);
#endif

U_BOOT_CMD_COMPLETE(
        setenv, CONFIG_SYS_MAXARGS, 0,  do_env_set,
        "set environment variables",
        "name value ...\n"
        "    - set environment variable 'name' to 'value ...'\n"
        "setenv name\n"
        "    - delete environment variable 'name'",
        var_complete
);

#if defined(CONFIG_CMD_ASKENV)

U_BOOT_CMD(
        askenv, CONFIG_SYS_MAXARGS,     1,      do_env_ask,
        "get environment variables from stdin",
        "name [message] [size]\n"
        "    - get environment variable 'name' from stdin (max 'size' chars)\n"
        "askenv name\n"
        "    - get environment variable 'name' from stdin\n"
        "askenv name size\n"
        "    - get environment variable 'name' from stdin (max 'size' chars)\n"
        "askenv name [message] size\n"
        "    - display 'message' string and get environment variable 'name'"
        "from stdin (max 'size' chars)"
);
#endif

#if defined(CONFIG_CMD_RUN)
U_BOOT_CMD_COMPLETE(
        run,    CONFIG_SYS_MAXARGS,     1,      do_run,
        "run commands in an environment variable",
        "var [...]\n"
        "    - run the commands in the environment variable(s) 'var'",
        var_complete
);
#endif
#endif /* CONFIG_SPL_BUILD */