Add a flag to nand_read_skip_bad() such that if true, any trailing pages in an eraseblock whose contents are entirely 0xff will be dropped.
The implementation is via a new drop_ffs() function which is based on the function of the same name from the ubiformat utility by Artem Bityutskiy. This is as-per the reccomendations of the UBI FAQ [1] Signed-off-by: Ben Gardiner <bengardi...@nanometrics.ca> CC: Artem Bityutskiy <dedeki...@gmail.com> [1] http://www.linux-mtd.infradead.org/doc/ubi.html#L_flasher_algo --- This behaviour was found to fix both UBI and JFFS2 images written to cleanly erased NAND partitions on da850evm. Changes since v1: * rebased to HEAD of git://git.denx.de/u-boot-nand-flash.git : ff7b4a0 ("env_nand: zero-initialize variable nand_erase_options") * wrap the new functionality in a CONFIG_CMD_NAND_TRIMFFS ifdef to reduce size impact of new feature --- drivers/mtd/nand/nand_util.c | 32 +++++++++++++++++++++++++++++--- include/nand.h | 1 + 2 files changed, 30 insertions(+), 3 deletions(-) diff --git a/drivers/mtd/nand/nand_util.c b/drivers/mtd/nand/nand_util.c index 03ccd02..2bfe743 100644 --- a/drivers/mtd/nand/nand_util.c +++ b/drivers/mtd/nand/nand_util.c @@ -436,6 +436,24 @@ static int check_skip_len(nand_info_t *nand, loff_t offset, size_t length) return ret; } +#ifdef CONFIG_CMD_NAND_TRIMFFS +static size_t drop_ffs(const nand_info_t *nand, const u_char *buf, + const size_t *len) +{ + size_t i, l = *len; + + for (i = l - 1; i >= 0; i--) + if (((const uint8_t *)buf)[i] != 0xFF) + break; + + /* The resulting length must be aligned to the minimum flash I/O size */ + l = i + 1; + l = (l + nand->writesize - 1) / nand->writesize; + l *= nand->writesize; + return l; +} +#endif + /** * nand_write_skip_bad: * @@ -499,7 +517,7 @@ int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length, return -EINVAL; } - if (!need_skip) { + if (!need_skip && !(flags & WITH_DROP_FFS)) { rval = nand_write (nand, offset, length, buffer); if (rval == 0) return 0; @@ -512,7 +530,7 @@ int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length, while (left_to_write > 0) { size_t block_offset = offset & (nand->erasesize - 1); - size_t write_size; + size_t write_size, truncated_write_size; WATCHDOG_RESET (); @@ -558,7 +576,15 @@ int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length, else #endif { - rval = nand_write (nand, offset, &write_size, p_buffer); + truncated_write_size = write_size; +#ifdef CONFIG_CMD_NAND_TRIMFFS + if (flags & WITH_DROP_FFS) + truncated_write_size = drop_ffs(nand, p_buffer, + &write_size); +#endif + + rval = nand_write(nand, offset, &truncated_write_size, + p_buffer); offset += write_size; p_buffer += write_size; } diff --git a/include/nand.h b/include/nand.h index 95b83a0..a5368e2 100644 --- a/include/nand.h +++ b/include/nand.h @@ -116,6 +116,7 @@ int nand_read_skip_bad(nand_info_t *nand, loff_t offset, size_t *length, u_char *buffer); #define WITH_YAFFS_OOB (1 << 0) /* whether write with yaffs format */ +#define WITH_DROP_FFS (1 << 1) /* drop trailing all-0xff pages */ #define WITH_DEFAULTS 0 int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length, -- 1.7.4.1 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
