diff --git a/board/hymod/env.c b/board/hymod/env.c
new file mode 100644
index 0000000..f58aec2
--- /dev/null
+++ b/board/hymod/env.c
@@ -0,0 +1,236 @@
+/*
+ * (C) Copyright 2003
+ * Murray Jensen, CSIRO-MIT, <Murray.Jensen@csiro.au>
+ *
+ * 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
+ */
+
+#include <common.h>
+
+/* imports from fetch.c */
+extern int fetch_and_parse (char *, ulong, int (*)(uchar *, uchar *));
+
+/* this is relative to the root of the server's tftp directory */
+static char *def_global_env_path = "/hymod/global_env";
+
+static int
+env_callback (uchar *name, uchar *value)
+{
+	DECLARE_GLOBAL_DATA_PTR;
+
+	hymod_conf_t *cp = &gd->bd->bi_hymod_conf;
+	char ov[CFG_CBSIZE], nv[CFG_CBSIZE], *p, *q, *nn, c, *curver, *newver;
+	int override = 1, append = 0, remove = 0, nnl, ovl, nvl;
+
+	nn = name;
+
+	if (*nn == '-') {
+		override = 0;
+		nn++;
+	}
+
+	while (*nn == ' ' || *nn == '\t')
+		nn++;
+
+	if ((nnl = strlen (nn)) == 0) {
+		printf ("Empty name in global env file\n");
+		return (0);
+	}
+
+	if ((c = nn[nnl - 1]) == '+' || c == '-') {
+		if (c == '+')
+			append = 1;
+		else
+			remove = 1;
+		nn[--nnl] = '\0';
+	}
+
+	while (nnl > 0 && ((c = nn[nnl - 1]) == ' ' || c == '\t'))
+		nn[--nnl] = '\0';
+	if (nnl == 0) {
+		printf ("Empty name in global env file\n");
+		return (0);
+	}
+
+	p = value;
+	q = nv;
+
+	while ((c = *p) == ' ' || c == '\t')
+		p++;
+
+	nvl = strlen (p);
+	while (nvl > 0 && ((c = p[nvl - 1]) == ' ' || c == '\t'))
+		p[--nvl] = '\0';
+
+	while ((*q = *p++) != '\0') {
+		if (*q == '%') {
+			switch (*p++) {
+
+			case '\0':	/* whoops - back up */
+				p--;
+				break;
+
+			case '%':	/* a single percent character */
+				q++;
+				break;
+
+			case 's':	/* main board serial number as string */
+				q += sprintf (q, "%010lu",
+					cp->main.eeprom.serno);
+				break;
+
+			case 'S':	/* main board serial number as number */
+				q += sprintf (q, "%lu", cp->main.eeprom.serno);
+				break;
+
+			default:	/* ignore any others */
+				break;
+			}
+		}
+		else
+			q++;
+	}
+
+	if ((nvl = q - nv) == 0) {
+		setenv (nn, NULL);
+		return (1);
+	}
+
+	if ((curver = getenv ("global_env_version")) == NULL)
+		curver = "unknown";
+
+	if ((newver = getenv ("new_genv_version")) == NULL || \
+	    strcmp (curver, newver) == 0) {
+		if (strcmp (nn, "version") == 0)
+			setenv ("new_genv_version", nv);
+		return (1);
+	}
+
+	if ((p = getenv (nn)) != NULL) {
+
+		strcpy (ov, p);
+		ovl = strlen (ov);
+
+		if (append) {
+
+			if (strstr (ov, nv) == NULL) {
+
+				printf ("Appending '%s' to env var '%s'\n",
+					nv, nn);
+
+				while (nvl >= 0) {
+					nv[ovl + 1 + nvl] = nv[nvl];
+					nvl--;
+				}
+
+				nv[ovl] = ' ';
+
+				while (--ovl >= 0)
+					nv[ovl] = ov[ovl];
+
+				setenv (nn, nv);
+			}
+
+			return (1);
+		}
+
+		if (remove) {
+
+			if (strstr (ov, nv) != NULL) {
+
+				printf ("Removing '%s' from env var '%s'\n",
+					nv, nn);
+
+				while ((p = strstr (ov, nv)) != NULL) {
+					q = p + nvl;
+					if (*q == ' ')
+						q++;
+					strcpy(p, q);
+				}
+
+				setenv (nn, ov);
+			}
+
+			return (1);
+		}
+
+		if (!override || strcmp (ov, nv) == 0)
+			return (1);
+
+		printf ("Re-setting env cmd '%s' from '%s' to '%s'\n",
+			nn, ov, nv);
+	}
+	else
+		printf ("Setting env cmd '%s' to '%s'\n", nn, nv);
+
+	setenv (nn, nv);
+	return (1);
+}
+
+void
+hymod_check_env (void)
+{
+	char *p, *path, *curver, *newver;
+	int firsttime = 0, needsave = 0;
+
+	if (getenv ("global_env_loaded") == NULL) {
+		puts ("*** global environment has never been loaded\n");
+		puts ("*** fetching from server");
+		firsttime = 1;
+	}
+	else if ((p = getenv ("always_check_env")) != NULL &&
+	    strcmp (p, "yes") == 0)
+		puts ("*** checking for updated global environment");
+	else
+		return;
+
+	puts (" (Control-C to Abort)\n");
+
+	if ((path = getenv ("global_env_path")) == NULL || *path == '\0')
+		path = def_global_env_path;
+
+	if (fetch_and_parse (path, CFG_LOAD_ADDR, env_callback) == 0) {
+		puts ("*** Fetch of global environment failed!\n");
+		return;
+	}
+
+	if ((newver = getenv ("new_genv_version")) == NULL) {
+		puts ("*** Version number not set - contents ignored!\n");
+		return;
+	}
+
+	if ((curver = getenv ("global_env_version")) == NULL || \
+	    strcmp (curver, newver) != 0) {
+		setenv ("global_env_version", newver);
+		needsave = 1;
+	}
+	else
+		printf ("*** Global environment up-to-date (ver %s)\n", curver);
+
+	setenv ("new_genv_version", NULL);
+
+	if (firsttime) {
+		setenv ("global_env_loaded", "yes");
+		needsave = 1;
+	}
+
+	if (needsave)
+		puts ("\n*** Remember to run the 'saveenv' "
+			"command to save the changes\n\n");
+}