From 93ad1a19872dfa2f4b9aa7b8d20581bda3057622 Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Sat, 26 Feb 2011 15:30:07 +0100 Subject: [PATCH 2/4] NAND: Optimize NAND_ECC_HW_OOB_FIRST read Avoid sending unnecessary READ commands to the chip. --- drivers/mtd/nand/nand_base.c | 15 +++++++++++---- 1 files changed, 11 insertions(+), 4 deletions(-) --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -1008,9 +1008,16 @@ static int nand_read_page_hwecc_oob_firs uint8_t *ecc_calc = chip->buffers->ecccalc; /* Read the OOB area first */ - chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page); - chip->read_buf(mtd, chip->oob_poi, mtd->oobsize); - chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page); + /* Read the OOB area first */ + if (mtd->writesize > 512) { + chip->cmdfunc(mtd, NAND_CMD_READ0, mtd->writesize, page); + chip->read_buf(mtd, chip->oob_poi, mtd->oobsize); + chip->cmdfunc(mtd, NAND_CMD_RNDOUT, 0, -1); + } else { + chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page); + chip->read_buf(mtd, chip->oob_poi, mtd->oobsize); + chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page); + } for (i = 0; i < chip->ecc.total; i++) ecc_code[i] = chip->oob_poi[eccpos[i]]; @@ -1177,7 +1184,7 @@ static int nand_do_read_ops(struct mtd_i if (realpage != chip->pagebuf || oob) { bufpoi = aligned ? buf : chip->buffers->databuf; - if (likely(sndcmd)) { + if (likely(sndcmd) && chip->ecc.mode != NAND_ECC_HW_OOB_FIRST) { chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page); sndcmd = 0; }