From fb5427508abbd635e877fabdf55795488119c2d6 Mon Sep 17 00:00:00 2001 From: Nicolas Ferre Date: Mon, 4 Jul 2011 16:17:53 +0200 Subject: [PATCH] mtd: atmel_nand: optimize read/write buffer functions For PIO NAND access functions, we use the features of the SMC: - no need to take into account the NAND bus width: SMC will deal with this - use of an IO memcpy on the NAND chip-select space is able to generate proper SMC behavior. Signed-off-by: Nicolas Ferre Signed-off-by: Artem Bityutskiy --- drivers/mtd/nand/atmel_nand.c | 45 ++++------------------------------- 1 file changed, 4 insertions(+), 41 deletions(-) diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c index ee6e26e78a1a..23e5d77c39fc 100644 --- a/drivers/mtd/nand/atmel_nand.c +++ b/drivers/mtd/nand/atmel_nand.c @@ -161,37 +161,6 @@ static int atmel_nand_device_ready(struct mtd_info *mtd) !!host->board->rdy_pin_active_low; } -/* - * Minimal-overhead PIO for data access. - */ -static void atmel_read_buf8(struct mtd_info *mtd, u8 *buf, int len) -{ - struct nand_chip *nand_chip = mtd->priv; - - __raw_readsb(nand_chip->IO_ADDR_R, buf, len); -} - -static void atmel_read_buf16(struct mtd_info *mtd, u8 *buf, int len) -{ - struct nand_chip *nand_chip = mtd->priv; - - __raw_readsw(nand_chip->IO_ADDR_R, buf, len / 2); -} - -static void atmel_write_buf8(struct mtd_info *mtd, const u8 *buf, int len) -{ - struct nand_chip *nand_chip = mtd->priv; - - __raw_writesb(nand_chip->IO_ADDR_W, buf, len); -} - -static void atmel_write_buf16(struct mtd_info *mtd, const u8 *buf, int len) -{ - struct nand_chip *nand_chip = mtd->priv; - - __raw_writesw(nand_chip->IO_ADDR_W, buf, len / 2); -} - static void dma_complete_func(void *completion) { complete(completion); @@ -266,33 +235,27 @@ err_buf: static void atmel_read_buf(struct mtd_info *mtd, u8 *buf, int len) { struct nand_chip *chip = mtd->priv; - struct atmel_nand_host *host = chip->priv; if (use_dma && len > mtd->oobsize) /* only use DMA for bigger than oob size: better performances */ if (atmel_nand_dma_op(mtd, buf, len, 1) == 0) return; - if (host->board->bus_width_16) - atmel_read_buf16(mtd, buf, len); - else - atmel_read_buf8(mtd, buf, len); + /* if no DMA operation possible, use PIO */ + memcpy_fromio(buf, chip->IO_ADDR_R, len); } static void atmel_write_buf(struct mtd_info *mtd, const u8 *buf, int len) { struct nand_chip *chip = mtd->priv; - struct atmel_nand_host *host = chip->priv; if (use_dma && len > mtd->oobsize) /* only use DMA for bigger than oob size: better performances */ if (atmel_nand_dma_op(mtd, (void *)buf, len, 0) == 0) return; - if (host->board->bus_width_16) - atmel_write_buf16(mtd, buf, len); - else - atmel_write_buf8(mtd, buf, len); + /* if no DMA operation possible, use PIO */ + memcpy_toio(chip->IO_ADDR_W, buf, len); } /* -- 2.34.1