[U-Boot] [PATCH] nand: adjust erase/read/write partition/chip size for bad blocks

[Harvey Chapman]

Sorry for all of the e-mails while I fumble with git send-email.

On Feb 26, 2013, at 12:43 AM, Harvey Chapman <hchapman at 3gfp.com> wrote:

> Adjust the sizes calculated for whole partition/chip operations by
> removing the size of bad blocks so we don't try to erase/read/write
> past a partition/chip boundary.
> 
> Signed-off-by: Harvey Chapman <hchapman at 3gfp.com>
> ---
> common/cmd_nand.c |   51 +++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 51 insertions(+)
> 
> diff --git a/common/cmd_nand.c b/common/cmd_nand.c
> index 495610c..657ea23 100644
> --- a/common/cmd_nand.c
> +++ b/common/cmd_nand.c
> @@ -428,6 +428,32 @@ static int raw_access(nand_info_t *nand, ulong addr, loff_t off, ulong count,
> 	return ret;
> }
> 
> +static int adjust_size_for_badblocks(loff_t *size, loff_t offset, int dev) {
> +	/* We grab the nand info object here fresh because this is usually
> +	 * called after arg_off_size() which can change the value of dev.
> +	 */
> +	nand_info_t *nand = &nand_info[dev];
> +	loff_t original_size = *size;
> +	loff_t maxoffset = offset + *size;
> +	int badblocks = 0;
> +
> +	/* count badblocks in NAND from offset to offset + size */
> +	for (; offset < maxoffset; offset += nand->erasesize)
> +		if (nand_block_isbad(nand, offset)) {
> +			badblocks++;
> +		}
> +	/* adjust size if any bad blocks found */
> +	if (badblocks) {
> +		*size -= badblocks * nand->erasesize;
> +		printf("size adjusted to 0x%llx (%d bad blocks)\n",
> +		       (unsigned long long)*size, badblocks);
> +	}
> +	/* return size adjusted as a positive value so callers
> +	 * can use the return code to determine if anything happened
> +	 */
> +	return (original_size - *size);
> +}
> +
> static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> {
> 	int i, ret = 0;
> @@ -524,6 +550,7 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> 		int scrub = !strncmp(cmd, "scrub", 5);
> 		int spread = 0;
> 		int args = 2;
> +		int adjust_size = 0;
> 		const char *scrub_warn =
> 			"Warning: "
> 			"scrub option will erase all factory set bad blocks!\n"
> @@ -540,8 +567,10 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> 				spread = 1;
> 			} else if (!strcmp(&cmd[5], ".part")) {
> 				args = 1;
> +				adjust_size = 1;
> 			} else if (!strcmp(&cmd[5], ".chip")) {
> 				args = 0;
> +				adjust_size = 1;
> 			} else {
> 				goto usage;
> 			}
> @@ -560,6 +589,15 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> 		if (arg_off_size(argc - o, argv + o, &dev, &off, &size) != 0)
> 			return 1;
> 
> +		/* The size for erase.part and erase.chip has been calculated
> +		 * for us as the remainder of the chip/partition from offset.
> +		 * Adjust down for bad blocks, if necessary, so we don't
> +		 * erase past the end of the chip/partition by accident.
> +		 */
> +		if (adjust_size && !scrub) {
> +			adjust_size_for_badblocks(&size, off, dev);
> +		}
> +
> 		nand = &nand_info[dev];
> 
> 		memset(&opts, 0, sizeof(opts));
> @@ -644,6 +682,19 @@ static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> 						&off, &size) != 0)
> 				return 1;
> 
> +			/* If no size was given, it has been calculated for us as
> +			 * the remainder of the chip/partition from offset. Adjust
> +			 * down for bad blocks, if necessary, so we don't
> +			 * read/write past the end of the partition by accident.
> +			 *
> +			 * nand read addr part size     "size" is arg 5
> +			 */
> +			if (argc < 5) {
> +				/* Don't try to use rwsize here, it's not the
> +				 * right type
> +				 */
> +				adjust_size_for_badblocks(&size, off, dev);
> +			}
> 			rwsize = size;
> 		}
> 
> -- 
> 1.7.10.4
> 
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