From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from up.free-electrons.com ([163.172.77.33] helo=mail.free-electrons.com) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1c02w6-0004aI-QV for linux-mtd@lists.infradead.org; Fri, 28 Oct 2016 08:54:51 +0000 Date: Fri, 28 Oct 2016 10:54:25 +0200 From: Boris Brezillon To: David Woodhouse , Brian Norris , linux-mtd@lists.infradead.org, Boris Brezillon , Richard Weinberger Cc: Marc Gonzalez Subject: Re: [PATCH 0/2] mtd: nand: Enforce tCCS wait time after a column change Message-ID: <20161028105425.61868d75@bbrezillon> In-Reply-To: <1475310243-32625-1-git-send-email-boris.brezillon@free-electrons.com> References: <1475310243-32625-1-git-send-email-boris.brezillon@free-electrons.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sat, 1 Oct 2016 10:24:01 +0200 Boris Brezillon wrote: > Hi, > > Marc recently struggled with the RNDIN/RNDOUT commands when trying to > add support for the Tango NAND controller. > After some investigation it appeared that nothing in the > nand_command_lp() code waits tCCS, which is required to make sure the > NAND chip is ready to receive/send data on the bus after a column > change. > > This series adds some more timings to the nand_sdr_timings struct > (including tCCS) and try to extract them from the ONFI parameter table > (if available). > > It then adds a new flags to ask the core to enforce the tCCS > constraint. > As noted in the commit message, this is an opt-in flag to avoid perf > regressions on existing implementations (adding an ndelay() might be > useless if the controller IP or driver already takes care of that), > but it might appear that some implementations are actually broken and > needs this flag as well. Applied. > > Regards, > > Boris > > Boris Brezillon (2): > mtd: nand: Add a few more timings to nand_sdr_timings > mtd: nand: Wait tCCS after a column change > > drivers/mtd/nand/nand_base.c | 26 +++++++++++++++++++++++++- > drivers/mtd/nand/nand_timings.c | 26 +++++++++++++++++++++++++- > include/linux/mtd/nand.h | 18 ++++++++++++++++++ > 3 files changed, 68 insertions(+), 2 deletions(-) >