Onenand sync burst mode-query

[Sameer]

Hi,
I am working on onenand driver based on omap board.
Onenand is samsung onenand. I need to add the functionality for
Synchronous burst mode operation which is currently not present.
I am refering n800 board driver (arch/arm/mach-omap/board-n880-flash.c)
The function "omap2_onenand_set_sync_mode" contains the variable "fclk_offset_ns"

I am not able to relate this variable with the timing diagram of the onenand flash
Could any body specify the significance of this variable and what how it
Is related to the timing variables?

Thanks,
-Sameer