From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Agner Subject: Re: [RESEND PATCH 2/5] mtd: rawnand: add NVIDIA Tegra NAND Flash controller driver Date: Thu, 24 May 2018 14:19:18 +0200 Message-ID: <146a3abbbff4dcef30ad662a0fb85ff1@agner.ch> References: <86fdf19ec92b732709732fb60199f16488b4b727.1526990589.git.stefan@agner.ch> <20180524135335.6aa0b7a4@bbrezillon> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180524135335.6aa0b7a4@bbrezillon> Sender: linux-kernel-owner@vger.kernel.org To: Boris Brezillon Cc: Benjamin Lindqvist , dwmw2@infradead.org, computersforpeace@gmail.com, marek.vasut@gmail.com, robh+dt@kernel.org, mark.rutland@arm.com, thierry.reding@gmail.com, mturquette@baylibre.com, sboyd@kernel.org, Lucas Stach , miquel.raynal@bootlin.com, richard@nod.at, marcel@ziswiler.com, krzk@kernel.org, digetx@gmail.com, jonathanh@nvidia.com, pdeschrijver@nvidia.com, pgaikwad@nvidia.com, Mirza Krak , linux-mtd@lists.infradead.org, linux-tegra@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org List-Id: devicetree@vger.kernel.org On 24.05.2018 13:53, Boris Brezillon wrote: > Hi Benjamin, > > On Thu, 24 May 2018 13:30:14 +0200 > Benjamin Lindqvist wrote: > >> Hi Stefan, >> >> It seems to me that a probe similar to what the BootROM does shouldn't >> be awfully complicated to implement - just cycle through the switch >> cases in case of an ECC error. But I guess that's more of an idea for >> further improvements rather than a comment to the patch set under >> review. > > Nope, not really an option, because you're not guaranteed that the NAND > will be used as a boot media, and the first page or first set of pages > might just be erased. > Yeah I did not meant probing like the Boot ROM does. What I meant was using only the ECC modes which are supported by the Boot ROM when the driver tries to choose a viable mode. So that would be: - RS t=4 - BCH t=8 - BCH t=16 Maybe we could add a property to enable that behavior: tegra,use-bootable-ecc-only; >> >> However, I think that allowing for an override of the oobsize >> inference would be a good idea before merging, no? This could just be >> a trivial #ifdef (at least temporarily). If you agree but don't feel >> like doing it yourself, I'd be happy to pitch in. Let me know. > > That's why we have nand-ecc-xxx properties in the DT. > Yes, nand-ecc-strength is the first thing I plan to implement, that way strength can be defined in dt. -- Stefan