It works, I changed config:
CONFIG_YAFFS_DOES_ECC=y
CONFIG_YAFFS_DISABLE_TAGS_ECC=y

--pawel


On Mon, Jun 8, 2015 at 2:56 PM, Pawel Jasinski <pawel.jasinski@gmail.com> wrote:
> Hi,
>
> I have a device with kernel 2.6.36.
> I am able to mount a yaffs file system and it appears to work.
> However, the files are gone after power cycle.
> What is the best way to diagnose this problem?
> Any hints are greatly appreciated.
>
> --pawel
>
> # grep YAFFS .config
> CONFIG_YAFFS_FS=y
> CONFIG_YAFFS_YAFFS1=y
> # CONFIG_YAFFS_9BYTE_TAGS is not set
> # CONFIG_YAFFS_DOES_ECC is not set
> CONFIG_YAFFS_YAFFS2=y
> CONFIG_YAFFS_AUTO_YAFFS2=y
> # CONFIG_YAFFS_DISABLE_TAGS_ECC is not set
> # CONFIG_YAFFS_DISABLE_WIDE_TNODES is not set
> # CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED is not set
> CONFIG_YAFFS_SHORT_NAMES_IN_RAM=y
> # CONFIG_YAFFS_EMPTY_LOST_AND_FOUND is not set
> # CONFIG_YAFFS_DISABLE_BLOCK_REFRESHING is not set
> # CONFIG_YAFFS_DISABLE_BACKGROUND is not set
> CONFIG_YAFFS_XATTR=y
>
> # ps | grep yaffs
> 94 0            0 SW   [yaffs-bg-1]
>
> # dmesgs
> ...
> yaffs: dev is 32505862 name is "mtdblock6" rw
> yaffs: passed flags ""
> yaffs: Attempting MTD mount of 31.6,"mtdblock6"
> yaffs_read_super: is_checkpointed 0
>
> # cat /proc/yaffs
> Multi-version YAFFS built:Jun  8 2015 09:08:54
>
>
> Device 0 "Overlay"
> start_block.......... 0
> end_block............ 665
> total_bytes_per_chunk 2048
> use_nand_ecc......... 1
> no_tags_ecc.......... 0
> is_yaffs2............ 1
> inband_tags.......... 0
> empty_lost_n_found... 0
> disable_lazy_load.... 0
> refresh_period....... 500
> n_caches............. 10
> n_reserved_blocks.... 5
> always_check_erased.. 0
>
> data_bytes_per_chunk. 2048
> chunk_grp_bits....... 0
> chunk_grp_size....... 1
> n_erased_blocks...... 623
> blocks_in_checkpt.... 0
>
> n_tnodes............. 199
> n_obj................ 69
> n_free_chunks........ 39969
>
> n_page_writes........ 4220
> n_page_reads......... 1757
> n_erasures........... 24
> n_gc_copies.......... 1466
> all_gcs.............. 301
> passive_gc_count..... 301
> oldest_dirty_gc_count 0
> n_gc_blocks.......... 24
> bg_gcs............... 24
> n_retired_writes..... 0
> nRetireBlocks........ 0
> n_ecc_fixed.......... 0
> n_ecc_unfixed........ 0
> n_tags_ecc_fixed..... 0
> n_tags_ecc_unfixed... 0
> cache_hits........... 0
> n_deleted_files...... 0
> n_unlinked_files..... 0
> refresh_count........ 1
> n_bg_deletions....... 0