Commits
Xiaolei Li committed 42d13a09efa
mtd: rawnand: mtk: Improve data sampling timing for read cycle Currently, we expand RE# low level time by choosing the max value between RE# pulse width and RE# access time, and sample data at the rising edge of RE#. Then, if RE# access time is bigger than RE# pulse width, the real read cycle time may be more than NAND SPEC required. This makes read performance be worse than that expected. This patch improves data sampling timing by calculating RE# low level time according to RE# pulse width. If RE# access time is bigger than RE# pulse width, then delay sampling data timing. The result of contrast test base on MT2712 evaluat board is as follow. nand: Micron MT29F16G08ADBCAH4 nand: 2048 MiB, SLC, erase size: 256 KiB, page size: 4096, OOB size: 224 NFI 2x clock rate: 124800000 HZ. Read speed without this patch: mtd_speedtest: page read speed is 14012 KiB/s mtd_speedtest: 2 page read speed is 14860 KiB/s Read speed with this patch: mtd_speedtest: page read speed is 18724 KiB/s mtd_speedtest: 2 page read speed is 18713 KiB/s Signed-off-by: Xiaolei Li <xiaolei.li@mediatek.com> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>