env: Add support for UBI environment

UBI is a better place for the environment on NAND devices because it
handles wear-leveling and bad blocks.

Gluebi is needed in Linux to access the env as an MTD partition.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

common/env_ubi.c

@@ -0,0 +1,103 @@
+/*
+ * (c) Copyright 2012 by National Instruments,
+ *        Joe Hershberger <joe.hershberger@ni.com>
+ *
+ * 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>
+
+#include <command.h>
+#include <environment.h>
+#include <errno.h>
+#include <malloc.h>
+#include <search.h>
+#include <ubi_uboot.h>
+#undef crc32
+
+char *env_name_spec = "UBI";
+
+env_t *env_ptr;
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int env_init(void)
+{
+	/* use default */
+	gd->env_addr = (ulong)&default_environment[0];
+	gd->env_valid = 1;
+
+	return 0;
+}
+
+#ifdef CONFIG_CMD_SAVEENV
+int saveenv(void)
+{
+	ALLOC_CACHE_ALIGN_BUFFER(env_t, env_new, 1);
+	ssize_t	len;
+	char *res;
+
+	res = (char *)&env_new->data;
+	len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
+	if (len < 0) {
+		error("Cannot export environment: errno = %d\n", errno);
+		return 1;
+	}
+
+	if (ubi_part(CONFIG_ENV_UBI_PART, NULL)) {
+		printf("\n** Cannot find mtd partition \"%s\"\n",
+		       CONFIG_ENV_UBI_PART);
+		return 1;
+	}
+
+	env_new->crc = crc32(0, env_new->data, ENV_SIZE);
+
+	if (ubi_volume_write(CONFIG_ENV_UBI_VOLUME, (void *)env_new,
+			     CONFIG_ENV_SIZE)) {
+		printf("\n** Unable to write env to %s:%s **\n",
+		       CONFIG_ENV_UBI_PART, CONFIG_ENV_UBI_VOLUME);
+		return 1;
+	}
+
+	puts("done\n");
+	return 0;
+}
+#endif /* CONFIG_CMD_SAVEENV */
+
+void env_relocate_spec(void)
+{
+	ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE);
+
+	if (ubi_part(CONFIG_ENV_UBI_PART, NULL)) {
+		printf("\n** Cannot find mtd partition \"%s\"\n",
+		       CONFIG_ENV_UBI_PART);
+		set_default_env(NULL);
+		return;
+	}
+
+	if (ubi_volume_read(CONFIG_ENV_UBI_VOLUME, (void *)&buf,
+			    CONFIG_ENV_SIZE)) {
+		printf("\n** Unable to read env from %s:%s **\n",
+		       CONFIG_ENV_UBI_PART, CONFIG_ENV_UBI_VOLUME);
+		set_default_env(NULL);
+		return;
+	}
+
+	env_import(buf, 1);
+}