From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qt0-x241.google.com ([2607:f8b0:400d:c0d::241]) by bombadil.infradead.org with esmtps (Exim 4.89 #1 (Red Hat Linux)) id 1eWSy3-0002kV-JZ for linux-mtd@lists.infradead.org; Tue, 02 Jan 2018 20:15:51 +0000 Received: by mail-qt0-x241.google.com with SMTP id g9so64209823qth.9 for ; Tue, 02 Jan 2018 12:15:12 -0800 (PST) From: Kamal Dasu To: boris.brezillon@free-electrons.com, linux-mtd@lists.infradead.org, bcm-kernel-feedback-list@broadcom.com Cc: computersforpeace@gmail.com, richard@nod.at, dwmw2@infradead.org, marek.vasut@gmail.com, cyrille.pitchen@wedev4u.fr, Kamal Dasu Subject: [PATCH] mtd: brcmnand: Disable prefetch by default Date: Tue, 2 Jan 2018 15:14:57 -0500 Message-Id: <1514924097-1630-1-git-send-email-kdasu.kdev@gmail.com> List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Brcm nand controller prefetch feature needs to be disabled by default. Enabling effects performance on random reads as well as dma reads. Signed-off-by: Kamal Dasu --- drivers/mtd/nand/brcmnand/brcmnand.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) diff --git a/drivers/mtd/nand/brcmnand/brcmnand.c b/drivers/mtd/nand/brcmnand/brcmnand.c index dd56a67..2a978d9 100644 --- a/drivers/mtd/nand/brcmnand/brcmnand.c +++ b/drivers/mtd/nand/brcmnand/brcmnand.c @@ -2193,16 +2193,9 @@ static int brcmnand_setup_dev(struct brcmnand_host *host) if (ctrl->nand_version >= 0x0702) tmp |= ACC_CONTROL_RD_ERASED; tmp &= ~ACC_CONTROL_FAST_PGM_RDIN; - if (ctrl->features & BRCMNAND_HAS_PREFETCH) { - /* - * FIXME: Flash DMA + prefetch may see spurious erased-page ECC - * errors - */ - if (has_flash_dma(ctrl)) - tmp &= ~ACC_CONTROL_PREFETCH; - else - tmp |= ACC_CONTROL_PREFETCH; - } + if (ctrl->features & BRCMNAND_HAS_PREFETCH) + tmp &= ~ACC_CONTROL_PREFETCH; + nand_writereg(ctrl, offs, tmp); return 0; -- 2.7.4