cmd_nand: some infrastructure fixes and refactoring

- If the current device is overridden by a named partition,
  - update the caller's pointer/index, rather than copy over the
    nand_info struct, and
  - be sure to call board_nand_select_device even when the device
    is overridden by a named partition.
- Support 64-bit offsets/sizes in a few more places.
- Refactor arg_off_size for added readability and flexibility,
  and some added checks such as partition size.
- Remove redundant check for bad subcommands -- if there's no match
  it'll print usage when it gets to the end anyway.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Tested-by: Ben Gardiner <bengardiner@nanometrics.ca>
diff --git a/common/cmd_nand.c b/common/cmd_nand.c
index 3f1d077..41aaf7f 100644
--- a/common/cmd_nand.c
+++ b/common/cmd_nand.c
@@ -10,6 +10,13 @@
  * (C) Copyright 2006-2007 OpenMoko, Inc.
  * Added 16-bit nand support
  * (C) 2004 Texas Instruments
+ *
+ * Copyright 2010 Freescale Semiconductor
+ * The portions of this file whose copyright is held by Freescale and which
+ * are not considered a derived work of GPL v2-only code may be distributed
+ * and/or modified 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.
  */
 
 #include <common.h>
@@ -85,74 +92,132 @@
 
 /* ------------------------------------------------------------------------- */
 
-static inline int str2long(char *p, ulong *num)
+static int set_dev(int dev)
+{
+	if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE ||
+	    !nand_info[dev].name) {
+		puts("No such device\n");
+		return -1;
+	}
+
+	if (nand_curr_device == dev)
+		return 0;
+
+	printf("Device %d: %s", dev, nand_info[dev].name);
+	puts("... is now current device\n");
+	nand_curr_device = dev;
+
+#ifdef CONFIG_SYS_NAND_SELECT_DEVICE
+	board_nand_select_device(nand_info[dev].priv, dev);
+#endif
+
+	return 0;
+}
+
+static inline int str2off(const char *p, loff_t *num)
+{
+	char *endptr;
+
+	*num = simple_strtoull(p, &endptr, 16);
+	return *p != '\0' && *endptr == '\0';
+}
+
+static inline int str2long(const char *p, ulong *num)
 {
 	char *endptr;
 
 	*num = simple_strtoul(p, &endptr, 16);
-	return (*p != '\0' && *endptr == '\0') ? 1 : 0;
+	return *p != '\0' && *endptr == '\0';
 }
 
-static int
-arg_off_size(int argc, char * const argv[], nand_info_t *nand, ulong *off, size_t *size)
+static int get_part(const char *partname, int *idx, loff_t *off, loff_t *size)
 {
-	int idx = nand_curr_device;
-#if defined(CONFIG_CMD_MTDPARTS)
+#ifdef CONFIG_CMD_MTDPARTS
 	struct mtd_device *dev;
 	struct part_info *part;
 	u8 pnum;
+	int ret;
 
-	if (argc >= 1 && !(str2long(argv[0], off))) {
-		if ((mtdparts_init() == 0) &&
-		    (find_dev_and_part(argv[0], &dev, &pnum, &part) == 0)) {
-			if (dev->id->type != MTD_DEV_TYPE_NAND) {
-				puts("not a NAND device\n");
-				return -1;
-			}
-			*off = part->offset;
-			if (argc >= 2) {
-				if (!(str2long(argv[1], (ulong *)size))) {
-					printf("'%s' is not a number\n", argv[1]);
-					return -1;
-				}
-				if (*size > part->size)
-					*size = part->size;
-			} else {
-				*size = part->size;
-			}
-			idx = dev->id->num;
-			*nand = nand_info[idx];
-			goto out;
-		}
+	ret = mtdparts_init();
+	if (ret)
+		return ret;
+
+	ret = find_dev_and_part(partname, &dev, &pnum, &part);
+	if (ret)
+		return ret;
+
+	if (dev->id->type != MTD_DEV_TYPE_NAND) {
+		puts("not a NAND device\n");
+		return -1;
 	}
-#endif
 
-	if (argc >= 1) {
-		if (!(str2long(argv[0], off))) {
-			printf("'%s' is not a number\n", argv[0]);
-			return -1;
-		}
-	} else {
+	*off = part->offset;
+	*size = part->size;
+	*idx = dev->id->num;
+
+	ret = set_dev(*idx);
+	if (ret)
+		return ret;
+
+	return 0;
+#else
+	puts("offset is not a number\n");
+	return -1;
+#endif
+}
+
+static int arg_off(const char *arg, int *idx, loff_t *off, loff_t *maxsize)
+{
+	if (!str2off(arg, off))
+		return get_part(arg, idx, off, maxsize);
+
+	if (*off >= nand_info[*idx].size) {
+		puts("Offset exceeds device limit\n");
+		return -1;
+	}
+
+	*maxsize = nand_info[*idx].size - *off;
+	return 0;
+}
+
+static int arg_off_size(int argc, char *const argv[], int *idx,
+			loff_t *off, loff_t *size)
+{
+	int ret;
+	loff_t maxsize;
+
+	if (argc == 0) {
 		*off = 0;
+		*size = nand_info[*idx].size;
+		goto print;
 	}
 
-	if (argc >= 2) {
-		if (!(str2long(argv[1], (ulong *)size))) {
-			printf("'%s' is not a number\n", argv[1]);
-			return -1;
-		}
-	} else {
-		*size = nand->size - *off;
+	ret = arg_off(argv[0], idx, off, &maxsize);
+	if (ret)
+		return ret;
+
+	if (argc == 1) {
+		*size = maxsize;
+		goto print;
 	}
 
-#if defined(CONFIG_CMD_MTDPARTS)
-out:
-#endif
-	printf("device %d ", idx);
-	if (*size == nand->size)
+	if (!str2off(argv[1], size)) {
+		printf("'%s' is not a number\n", argv[1]);
+		return -1;
+	}
+
+	if (*size > maxsize) {
+		puts("Size exceeds partition or device limit\n");
+		return -1;
+	}
+
+print:
+	printf("device %d ", *idx);
+	if (*size == nand_info[*idx].size)
 		puts("whole chip\n");
 	else
-		printf("offset 0x%lx, size 0x%zx\n", *off, *size);
+		printf("offset 0x%llx, size 0x%llx\n",
+		       (unsigned long long)*off, (unsigned long long)*size);
 	return 0;
 }
 
@@ -200,14 +265,20 @@
 #ifdef CONFIG_ENV_OFFSET_OOB
 unsigned long nand_env_oob_offset;
 
-int do_nand_env_oob(cmd_tbl_t *cmdtp, nand_info_t *nand,
-		    int argc, char * const argv[])
+int do_nand_env_oob(cmd_tbl_t *cmdtp, int argc, char *const argv[])
 {
 	int ret;
 	uint32_t oob_buf[ENV_OFFSET_SIZE/sizeof(uint32_t)];
-
+	nand_info_t *nand = &nand_info[0];
 	char *cmd = argv[1];
 
+	if (CONFIG_SYS_MAX_NAND_DEVICE == 0 || !nand->name) {
+		puts("no devices available\n");
+		return 1;
+	}
+
+	set_dev(0);
+
 	if (!strcmp(cmd, "get")) {
 		ret = get_nand_env_oob(nand, &nand_env_oob_offset);
 		if (ret)
@@ -215,16 +286,21 @@
 
 		printf("0x%08lx\n", nand_env_oob_offset);
 	} else if (!strcmp(cmd, "set")) {
-		ulong addr;
-		size_t dummy_size;
+		loff_t addr;
+		loff_t maxsize;
 		struct mtd_oob_ops ops;
+		int idx = 0;
 
 		if (argc < 3)
 			goto usage;
 
-		if (arg_off_size(argc - 2, argv + 2, nand, &addr,
-				 &dummy_size) < 0) {
-			printf("Offset or partition name expected\n");
+		if (arg_off(argv[2], &idx, &addr, &maxsize)) {
+			puts("Offset or partition name expected\n");
+			return 1;
+		}
+
+		if (idx != 0) {
+			puts("Partition not on first NAND device\n");
 			return 1;
 		}
 
@@ -264,8 +340,8 @@
 
 		if (addr != nand_env_oob_offset) {
 			printf("Verification of env offset in OOB failed: "
-			       "0x%08lx expected but got 0x%08lx\n",
-			       addr, nand_env_oob_offset);
+			       "0x%08llx expected but got 0x%08lx\n",
+			       (unsigned long long)addr, nand_env_oob_offset);
 			return 1;
 		}
 	} else {
@@ -293,9 +369,9 @@
 
 int do_nand(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
 {
-	int i, dev, ret = 0;
-	ulong addr, off;
-	size_t size;
+	int i, ret = 0;
+	ulong addr;
+	loff_t off, size;
 	char *cmd, *s;
 	nand_info_t *nand;
 #ifdef CONFIG_SYS_NAND_QUIET
@@ -304,6 +380,7 @@
 	int quiet = 0;
 #endif
 	const char *quiet_str = getenv("quiet");
+	int dev = nand_curr_device;
 
 	/* at least two arguments please */
 	if (argc < 2)
@@ -325,68 +402,45 @@
 	}
 
 	if (strcmp(cmd, "device") == 0) {
-
 		if (argc < 3) {
 			putc('\n');
-			if ((nand_curr_device < 0) ||
-			    (nand_curr_device >= CONFIG_SYS_MAX_NAND_DEVICE))
+			if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE)
 				puts("no devices available\n");
 			else
-				nand_print_info(nand_curr_device);
+				nand_print_info(dev);
 			return 0;
 		}
-		dev = (int)simple_strtoul(argv[2], NULL, 10);
-		if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE || !nand_info[dev].name) {
-			puts("No such device\n");
-			return 1;
-		}
-		printf("Device %d: %s", dev, nand_info[dev].name);
-		puts("... is now current device\n");
-		nand_curr_device = dev;
 
-#ifdef CONFIG_SYS_NAND_SELECT_DEVICE
-		/*
-		 * Select the chip in the board/cpu specific driver
-		 */
-		board_nand_select_device(nand_info[dev].priv, dev);
-#endif
+		dev = (int)simple_strtoul(argv[2], NULL, 10);
+		set_dev(dev);
 
 		return 0;
 	}
 
-	if (strcmp(cmd, "bad") != 0 && strcmp(cmd, "erase") != 0 &&
-	    strncmp(cmd, "dump", 4) != 0 &&
-	    strncmp(cmd, "read", 4) != 0 && strncmp(cmd, "write", 5) != 0 &&
-	    strcmp(cmd, "scrub") != 0 && strcmp(cmd, "markbad") != 0 &&
-	    strcmp(cmd, "biterr") != 0 &&
-	    strcmp(cmd, "lock") != 0 && strcmp(cmd, "unlock") != 0
-#ifdef CONFIG_ENV_OFFSET_OOB
-	    && strcmp(cmd, "env.oob") != 0
-#endif
-	    )
-		goto usage;
-
 #ifdef CONFIG_ENV_OFFSET_OOB
 	/* this command operates only on the first nand device */
-	if (strcmp(cmd, "env.oob") == 0) {
-		return do_nand_env_oob(cmdtp, &nand_info[0],
-				       argc - 1, argv + 1);
-	}
+	if (strcmp(cmd, "env.oob") == 0)
+		return do_nand_env_oob(cmdtp, argc - 1, argv + 1);
 #endif
 
-	/* the following commands operate on the current device */
-	if (nand_curr_device < 0 || nand_curr_device >= CONFIG_SYS_MAX_NAND_DEVICE ||
-	    !nand_info[nand_curr_device].name) {
+	/* The following commands operate on the current device, unless
+	 * overridden by a partition specifier.  Note that if somehow the
+	 * current device is invalid, it will have to be changed to a valid
+	 * one before these commands can run, even if a partition specifier
+	 * for another device is to be used.
+	 */
+	if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE ||
+	    !nand_info[dev].name) {
 		puts("\nno devices available\n");
 		return 1;
 	}
-	nand = &nand_info[nand_curr_device];
+	nand = &nand_info[dev];
 
 	if (strcmp(cmd, "bad") == 0) {
-		printf("\nDevice %d bad blocks:\n", nand_curr_device);
+		printf("\nDevice %d bad blocks:\n", dev);
 		for (off = 0; off < nand->size; off += nand->erasesize)
 			if (nand_block_isbad(nand, off))
-				printf("  %08lx\n", off);
+				printf("  %08llx\n", (unsigned long long)off);
 		return 0;
 	}
 
@@ -404,9 +458,11 @@
 
 		printf("\nNAND %s: ", scrub ? "scrub" : "erase");
 		/* skip first two or three arguments, look for offset and size */
-		if (arg_off_size(argc - o, argv + o, nand, &off, &size) != 0)
+		if (arg_off_size(argc - o, argv + o, &dev, &off, &size) != 0)
 			return 1;
 
+		nand = &nand_info[dev];
+
 		memset(&opts, 0, sizeof(opts));
 		opts.offset = off;
 		opts.length = size;
@@ -462,6 +518,7 @@
 	}
 
 	if (strncmp(cmd, "read", 4) == 0 || strncmp(cmd, "write", 5) == 0) {
+		size_t rwsize;
 		int read;
 
 		if (argc < 4)
@@ -471,23 +528,26 @@
 
 		read = strncmp(cmd, "read", 4) == 0; /* 1 = read, 0 = write */
 		printf("\nNAND %s: ", read ? "read" : "write");
-		if (arg_off_size(argc - 3, argv + 3, nand, &off, &size) != 0)
+		if (arg_off_size(argc - 3, argv + 3, &dev, &off, &size) != 0)
 			return 1;
 
+		nand = &nand_info[dev];
+		rwsize = size;
+
 		s = strchr(cmd, '.');
 		if (!s || !strcmp(s, ".jffs2") ||
 		    !strcmp(s, ".e") || !strcmp(s, ".i")) {
 			if (read)
-				ret = nand_read_skip_bad(nand, off, &size,
+				ret = nand_read_skip_bad(nand, off, &rwsize,
 							 (u_char *)addr);
 			else
-				ret = nand_write_skip_bad(nand, off, &size,
+				ret = nand_write_skip_bad(nand, off, &rwsize,
 							  (u_char *)addr);
 		} else if (!strcmp(s, ".oob")) {
 			/* out-of-band data */
 			mtd_oob_ops_t ops = {
 				.oobbuf = (u8 *)addr,
-				.ooblen = size,
+				.ooblen = rwsize,
 				.mode = MTD_OOB_RAW
 			};
 
@@ -500,7 +560,7 @@
 			return 1;
 		}
 
-		printf(" %zu bytes %s: %s\n", size,
+		printf(" %zu bytes %s: %s\n", rwsize,
 		       read ? "read" : "written", ret ? "ERROR" : "OK");
 
 		return ret == 0 ? 0 : 1;
@@ -564,7 +624,7 @@
 		if (arg_off_size(argc - 2, argv + 2, nand, &off, &size) < 0)
 			return 1;
 
-		if (!nand_unlock(nand, off, size)) {
+		if (!nand_unlock(&nand_info[dev], off, size)) {
 			puts("NAND flash successfully unlocked\n");
 		} else {
 			puts("Error unlocking NAND flash, "