nand: extend nand torture

nand torture currently works on exactly one nand block which is specified
by giving the byteoffset to the beginning of the block.

Extend this by allowing for a second parameter specifying the byte size
to be tested.

e.g.
==> nand torture 1000000

NAND torture: device 0 offset 0x1000000 size 0x20000 (block size 0x20000)
 Passed: 1, failed: 0

==> nand torture 1000000 40000

NAND torture: device 0 offset 0x1000000 size 0x40000 (block size 0x20000)
 Passed: 2, failed: 0

Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
[scottwood: fix usage to show size as optional, and add misssing braces]
Signed-off-by: Scott Wood <oss@buserror.net>

cmd/nand.c

@@ -647,6 +647,9 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 
 #ifdef CONFIG_CMD_NAND_TORTURE
 	if (strcmp(cmd, "torture") == 0) {
+		loff_t endoff;
+		unsigned int failed = 0, passed = 0;
+
 		if (argc < 3)
 			goto usage;
 
@@ -655,12 +658,37 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 			return 1;
 		}
 
-		printf("\nNAND torture: device %d offset 0x%llx size 0x%x\n",
+		size = mtd->erasesize;
-			dev, off, mtd->erasesize);
+		if (argc > 3) {
-		ret = nand_torture(mtd, off);
+			if (!str2off(argv[3], &size)) {
-		printf(" %s\n", ret ? "Failed" : "Passed");
+				puts("Size is not a valid number\n");
+				return 1;
+			}
+		}
 
-		return ret == 0 ? 0 : 1;
+		endoff = off + size;
+		if (endoff > mtd->size) {
+			puts("Arguments beyond end of NAND\n");
+			return 1;
+		}
+
+		off = round_down(off, mtd->erasesize);
+		endoff = round_up(endoff, mtd->erasesize);
+		size = endoff - off;
+		printf("\nNAND torture: device %d offset 0x%llx size 0x%llx (block size 0x%x)\n",
+		       dev, off, size, mtd->erasesize);
+		while (off < endoff) {
+			ret = nand_torture(mtd, off);
+			if (ret) {
+				failed++;
+				printf("  block at 0x%llx failed\n", off);
+			} else {
+				passed++;
+			}
+			off += mtd->erasesize;
+		}
+		printf(" Passed: %u, failed: %u\n", passed, failed);
+		return failed != 0;
 	}
 #endif
 
@@ -775,7 +803,8 @@ static char nand_help_text[] =
 	"nand bad - show bad blocks\n"
 	"nand dump[.oob] off - dump page\n"
 #ifdef CONFIG_CMD_NAND_TORTURE
-	"nand torture off - torture block at offset\n"
+	"nand torture off - torture one block at offset\n"
+	"nand torture off [size] - torture blocks from off to off+size\n"
 #endif
 	"nand scrub [-y] off size | scrub.part partition | scrub.chip\n"
 	"    really clean NAND erasing bad blocks (UNSAFE)\n"

doc/README.nand

@@ -307,7 +307,7 @@ Miscellaneous and testing commands:
   DANGEROUS!!! Factory set bad blocks will be lost. Use only
   to remove artificial bad blocks created with the "markbad" command.
 
-  "torture offset"
+  "torture offset [size]"
   Torture block to determine if it is still reliable.
   Enabled by the CONFIG_CMD_NAND_TORTURE configuration option.
   This command returns 0 if the block is still reliable, else 1.
@@ -324,6 +324,10 @@ Miscellaneous and testing commands:
   automate actions following a nand->write() error. This would e.g. be required
   in order to program or update safely firmware to NAND, especially for the UBI
   part of such firmware.
+  Optionally, a second parameter size can be given to test multiple blocks with
+  one call. If size is not a multiple of the NAND's erase size, then the block
+  that contains offset + size will be tested in full. If used with size, this
+  command returns 0 if all tested blocks have been found reliable, else 1.
 
 
 NAND locking command (for chips with active LOCKPRE pin)