Abstract: A solution for combining a portion of data from a block of single level cells to a block of multi-level cells. The solution includes identifying word lines with only valid data and word lines with non-valid data in a selected block of single level cells, copying data from word lines with valid data to a destination block of multi-level cells and copying data from word lines in the selected block of single level cells with non-valid data to a separate compaction block of single level cells. The system includes a first controller module configured to scan for word lines with only valid data and pass a bitmap identifying valid and invalid word lines to a second controller module. The second controller module is configured to perform on-chip combining of data from valid word lines, and copy data from invalid data word lines to a compaction block of single level cells.

Abstract: A method and system for folding only a portion of data from an SLC block to an MLC block is described. The method includes identifying word lines with only valid data and word lines with non-valid data in a selected SLC block, copying data only from word lines with valid data to a destination MLC block and copying data from word lines in the selected SLC block with non-valid data to a separate SLC compaction block. The system includes a first controller module configured to scan for word lines with only valid data and pass only a bitmap regarding valid and invalid word lines to a second controller module. The second controller module is configured to perform on-chip folding of data from valid word lines, and to copy data from invalid data word lines to an SLC compaction block.

Abstract: Apparatus and methods implemented therein, in response to receiving an indication to program data to both a primary and secondary memory page determine whether a folding operation is in progress. In response to determining that the folding operation is in progress, programming of the data is delayed until completion of the folding operation. In response to determining the completion of the folding operation, data is programmed to the primary memory page and secondary memory page.