From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53C75C4321D for ; Tue, 21 Aug 2018 10:44:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0AF352170E for ; Tue, 21 Aug 2018 10:44:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0AF352170E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727161AbeHUODo (ORCPT ); Tue, 21 Aug 2018 10:03:44 -0400 Received: from mail.bootlin.com ([62.4.15.54]:38580 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726784AbeHUODo (ORCPT ); Tue, 21 Aug 2018 10:03:44 -0400 Received: by mail.bootlin.com (Postfix, from userid 110) id AC367207C8; Tue, 21 Aug 2018 12:44:02 +0200 (CEST) Received: from bbrezillon (91-160-177-164.subs.proxad.net [91.160.177.164]) by mail.bootlin.com (Postfix) with ESMTPSA id D7BDB207BF; Tue, 21 Aug 2018 12:43:51 +0200 (CEST) Date: Tue, 21 Aug 2018 12:43:52 +0200 From: Boris Brezillon To: Srinivas Kandagatla Cc: Alban , Bartosz Golaszewski , Jonathan Corbet , Sekhar Nori , Kevin Hilman , Russell King , Arnd Bergmann , Greg Kroah-Hartman , David Woodhouse , Brian Norris , Marek Vasut , Richard Weinberger , Grygorii Strashko , "David S . Miller" , Naren , Mauro Carvalho Chehab , Andrew Morton , Lukas Wunner , Dan Carpenter , Florian Fainelli , Ivan Khoronzhuk , Sven Van Asbroeck , Paolo Abeni , Rob Herring , David Lechner , Andrew Lunn , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-i2c@vger.kernel.org, linux-mtd@lists.infradead.org, linux-omap@vger.kernel.org, netdev@vger.kernel.org, Bartosz Golaszewski Subject: Re: [PATCH v2 06/29] mtd: Add support for reading MTD devices via the nvmem API Message-ID: <20180821124352.21340939@bbrezillon> In-Reply-To: References: <20180810080526.27207-1-brgl@bgdev.pl> <20180810080526.27207-7-brgl@bgdev.pl> <20180817182720.6a6e5e8e@bbrezillon> <20180819133106.0420df5f@tock> <20180819184609.6dcdbb9a@bbrezillon> <5b8c30b8-41e1-d59e-542b-fef6c6469ff0@linaro.org> <20180820202038.5d3dc195@bbrezillon> <20180821115639.4894c1c9@bbrezillon> X-Mailer: Claws Mail 3.15.0-dirty (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 21 Aug 2018 11:11:58 +0100 Srinivas Kandagatla wrote: > On 21/08/18 10:56, Boris Brezillon wrote: > > On Tue, 21 Aug 2018 10:50:07 +0100 > > Srinivas Kandagatla wrote: > > > >> On 20/08/18 19:20, Boris Brezillon wrote: > >>> On Mon, 20 Aug 2018 11:43:34 +0100 > >>> Srinivas Kandagatla wrote: > >>> > >>>> Overall am still not able to clear visualize on how MTD bindings with > >>>> nvmem cells would look in both partition and un-partition usecases? > >>>> An example DT would be nice here!! > >>> Something along those lines: > >>> > >> This looks good to me. > >>> mtdnode { > >>> nvmem-cells { > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> cell@0 { > >>> reg = <0x0 0x14>; > >>> }; > >>> }; > >>> > >>> partitions { > >>> compatible = "fixed-partitions"; > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> partition@0 { > >>> reg = <0x0 0x20000>; > >>> > >>> nvmem-cells { > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> cell@0 { > >>> reg = <0x0 0x10>; > >>> }; > >>> }; > >>> }; > >>> }; > >>> }; > > >> Just curious...Is there a reason why we can't do it like this?: > >> Is this because of issue of #address-cells and #size-cells Or mtd > >> bindings always prefer subnodes? > >> > >> mtdnode { > >> reg = <0x0123000 0x40000>; > >> #address-cells = <1>; > >> #size-cells = <1>; > >> cell@0 { > >> compatible = "nvmem-cell"; > >> reg = <0x0 0x14>; > >> }; > >> > >> partitions { > >> compatible = "fixed-partitions"; > >> #address-cells = <1>; > >> #size-cells = <1>; > >> > >> partition@0 { > >> reg = <0x0 0x20000>; > >> cell@0 { > >> compatible = "nvmem-cell"; > >> reg = <0x0 0x10>; > >> }; > >> }; > >> }; > >> }; > > It's because partitions were initially directly defined under the mtd > > node, so, if you have an old DT you might have something like: > > > > mtdnode { > > reg = <0x0123000 0x40000>; > > #address-cells = <1>; > > #size-cells = <1>; > > > > partition@0 { > > reg = <0x0 0x20000>; > > ... > > }; > > ... > > }; > > > > If we use such a DT with this patch applied, the NVMEM framework will > > consider MTD partitions as nvmem cells, which is not what we want. > Yep, I agree. > TBH, I wanted to add compatible string to nvmem-cell at some point in > time and it seems more natural update too. One of the reason we > discussed this in the past was parsers. Looks like mtd can make use of this. > > We should be able to add this as an optional flag in nvmem_config to > enforce this check in case providers wanted to. > > Do you think that would help mtd nvmem case? Yes, it should work if nvmem cells are defined directly under the mtd node (or the partition they belong to). > Also I felt like nvmem-cells subnode seems to be a bit heavy! I still think grouping nvmem cells in a subnode is cleaner (just like we do for partitions), but I won't object if all parties (you, Alban and Rob) agree on this solution. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [PATCH v2 06/29] mtd: Add support for reading MTD devices via the nvmem API Date: Tue, 21 Aug 2018 12:43:52 +0200 Message-ID: <20180821124352.21340939@bbrezillon> References: <20180810080526.27207-1-brgl@bgdev.pl> <20180810080526.27207-7-brgl@bgdev.pl> <20180817182720.6a6e5e8e@bbrezillon> <20180819133106.0420df5f@tock> <20180819184609.6dcdbb9a@bbrezillon> <5b8c30b8-41e1-d59e-542b-fef6c6469ff0@linaro.org> <20180820202038.5d3dc195@bbrezillon> <20180821115639.4894c1c9@bbrezillon> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Alban , Bartosz Golaszewski , Jonathan Corbet , Sekhar Nori , Kevin Hilman , Russell King , Arnd Bergmann , Greg Kroah-Hartman , David Woodhouse , Brian Norris , Marek Vasut , Richard Weinberger , Grygorii Strashko , "David S . Miller" , Naren , Mauro Carvalho Chehab , Andrew Morton , Lukas Wunner , Dan Carpenter , Florian Fainelli Return-path: Received: from mail.bootlin.com ([62.4.15.54]:38580 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726784AbeHUODo (ORCPT ); Tue, 21 Aug 2018 10:03:44 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 21 Aug 2018 11:11:58 +0100 Srinivas Kandagatla wrote: > On 21/08/18 10:56, Boris Brezillon wrote: > > On Tue, 21 Aug 2018 10:50:07 +0100 > > Srinivas Kandagatla wrote: > > > >> On 20/08/18 19:20, Boris Brezillon wrote: > >>> On Mon, 20 Aug 2018 11:43:34 +0100 > >>> Srinivas Kandagatla wrote: > >>> > >>>> Overall am still not able to clear visualize on how MTD bindings with > >>>> nvmem cells would look in both partition and un-partition usecases? > >>>> An example DT would be nice here!! > >>> Something along those lines: > >>> > >> This looks good to me. > >>> mtdnode { > >>> nvmem-cells { > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> cell@0 { > >>> reg = <0x0 0x14>; > >>> }; > >>> }; > >>> > >>> partitions { > >>> compatible = "fixed-partitions"; > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> partition@0 { > >>> reg = <0x0 0x20000>; > >>> > >>> nvmem-cells { > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> cell@0 { > >>> reg = <0x0 0x10>; > >>> }; > >>> }; > >>> }; > >>> }; > >>> }; > > >> Just curious...Is there a reason why we can't do it like this?: > >> Is this because of issue of #address-cells and #size-cells Or mtd > >> bindings always prefer subnodes? > >> > >> mtdnode { > >> reg = <0x0123000 0x40000>; > >> #address-cells = <1>; > >> #size-cells = <1>; > >> cell@0 { > >> compatible = "nvmem-cell"; > >> reg = <0x0 0x14>; > >> }; > >> > >> partitions { > >> compatible = "fixed-partitions"; > >> #address-cells = <1>; > >> #size-cells = <1>; > >> > >> partition@0 { > >> reg = <0x0 0x20000>; > >> cell@0 { > >> compatible = "nvmem-cell"; > >> reg = <0x0 0x10>; > >> }; > >> }; > >> }; > >> }; > > It's because partitions were initially directly defined under the mtd > > node, so, if you have an old DT you might have something like: > > > > mtdnode { > > reg = <0x0123000 0x40000>; > > #address-cells = <1>; > > #size-cells = <1>; > > > > partition@0 { > > reg = <0x0 0x20000>; > > ... > > }; > > ... > > }; > > > > If we use such a DT with this patch applied, the NVMEM framework will > > consider MTD partitions as nvmem cells, which is not what we want. > Yep, I agree. > TBH, I wanted to add compatible string to nvmem-cell at some point in > time and it seems more natural update too. One of the reason we > discussed this in the past was parsers. Looks like mtd can make use of this. > > We should be able to add this as an optional flag in nvmem_config to > enforce this check in case providers wanted to. > > Do you think that would help mtd nvmem case? Yes, it should work if nvmem cells are defined directly under the mtd node (or the partition they belong to). > Also I felt like nvmem-cells subnode seems to be a bit heavy! I still think grouping nvmem cells in a subnode is cleaner (just like we do for partitions), but I won't object if all parties (you, Alban and Rob) agree on this solution. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [PATCH v2 06/29] mtd: Add support for reading MTD devices via the nvmem API Date: Tue, 21 Aug 2018 12:43:52 +0200 Message-ID: <20180821124352.21340939@bbrezillon> References: <20180810080526.27207-1-brgl@bgdev.pl> <20180810080526.27207-7-brgl@bgdev.pl> <20180817182720.6a6e5e8e@bbrezillon> <20180819133106.0420df5f@tock> <20180819184609.6dcdbb9a@bbrezillon> <5b8c30b8-41e1-d59e-542b-fef6c6469ff0@linaro.org> <20180820202038.5d3dc195@bbrezillon> <20180821115639.4894c1c9@bbrezillon> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: netdev-owner@vger.kernel.org To: Srinivas Kandagatla Cc: Alban , Bartosz Golaszewski , Jonathan Corbet , Sekhar Nori , Kevin Hilman , Russell King , Arnd Bergmann , Greg Kroah-Hartman , David Woodhouse , Brian Norris , Marek Vasut , Richard Weinberger , Grygorii Strashko , "David S . Miller" , Naren , Mauro Carvalho Chehab , Andrew Morton , Lukas Wunner , Dan Carpenter , Florian Fainelli List-Id: linux-i2c@vger.kernel.org On Tue, 21 Aug 2018 11:11:58 +0100 Srinivas Kandagatla wrote: > On 21/08/18 10:56, Boris Brezillon wrote: > > On Tue, 21 Aug 2018 10:50:07 +0100 > > Srinivas Kandagatla wrote: > > > >> On 20/08/18 19:20, Boris Brezillon wrote: > >>> On Mon, 20 Aug 2018 11:43:34 +0100 > >>> Srinivas Kandagatla wrote: > >>> > >>>> Overall am still not able to clear visualize on how MTD bindings with > >>>> nvmem cells would look in both partition and un-partition usecases? > >>>> An example DT would be nice here!! > >>> Something along those lines: > >>> > >> This looks good to me. > >>> mtdnode { > >>> nvmem-cells { > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> cell@0 { > >>> reg = <0x0 0x14>; > >>> }; > >>> }; > >>> > >>> partitions { > >>> compatible = "fixed-partitions"; > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> partition@0 { > >>> reg = <0x0 0x20000>; > >>> > >>> nvmem-cells { > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> cell@0 { > >>> reg = <0x0 0x10>; > >>> }; > >>> }; > >>> }; > >>> }; > >>> }; > > >> Just curious...Is there a reason why we can't do it like this?: > >> Is this because of issue of #address-cells and #size-cells Or mtd > >> bindings always prefer subnodes? > >> > >> mtdnode { > >> reg = <0x0123000 0x40000>; > >> #address-cells = <1>; > >> #size-cells = <1>; > >> cell@0 { > >> compatible = "nvmem-cell"; > >> reg = <0x0 0x14>; > >> }; > >> > >> partitions { > >> compatible = "fixed-partitions"; > >> #address-cells = <1>; > >> #size-cells = <1>; > >> > >> partition@0 { > >> reg = <0x0 0x20000>; > >> cell@0 { > >> compatible = "nvmem-cell"; > >> reg = <0x0 0x10>; > >> }; > >> }; > >> }; > >> }; > > It's because partitions were initially directly defined under the mtd > > node, so, if you have an old DT you might have something like: > > > > mtdnode { > > reg = <0x0123000 0x40000>; > > #address-cells = <1>; > > #size-cells = <1>; > > > > partition@0 { > > reg = <0x0 0x20000>; > > ... > > }; > > ... > > }; > > > > If we use such a DT with this patch applied, the NVMEM framework will > > consider MTD partitions as nvmem cells, which is not what we want. > Yep, I agree. > TBH, I wanted to add compatible string to nvmem-cell at some point in > time and it seems more natural update too. One of the reason we > discussed this in the past was parsers. Looks like mtd can make use of this. > > We should be able to add this as an optional flag in nvmem_config to > enforce this check in case providers wanted to. > > Do you think that would help mtd nvmem case? Yes, it should work if nvmem cells are defined directly under the mtd node (or the partition they belong to). > Also I felt like nvmem-cells subnode seems to be a bit heavy! I still think grouping nvmem cells in a subnode is cleaner (just like we do for partitions), but I won't object if all parties (you, Alban and Rob) agree on this solution. From mboxrd@z Thu Jan 1 00:00:00 1970 From: boris.brezillon@bootlin.com (Boris Brezillon) Date: Tue, 21 Aug 2018 12:43:52 +0200 Subject: [PATCH v2 06/29] mtd: Add support for reading MTD devices via the nvmem API In-Reply-To: References: <20180810080526.27207-1-brgl@bgdev.pl> <20180810080526.27207-7-brgl@bgdev.pl> <20180817182720.6a6e5e8e@bbrezillon> <20180819133106.0420df5f@tock> <20180819184609.6dcdbb9a@bbrezillon> <5b8c30b8-41e1-d59e-542b-fef6c6469ff0@linaro.org> <20180820202038.5d3dc195@bbrezillon> <20180821115639.4894c1c9@bbrezillon> Message-ID: <20180821124352.21340939@bbrezillon> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, 21 Aug 2018 11:11:58 +0100 Srinivas Kandagatla wrote: > On 21/08/18 10:56, Boris Brezillon wrote: > > On Tue, 21 Aug 2018 10:50:07 +0100 > > Srinivas Kandagatla wrote: > > > >> On 20/08/18 19:20, Boris Brezillon wrote: > >>> On Mon, 20 Aug 2018 11:43:34 +0100 > >>> Srinivas Kandagatla wrote: > >>> > >>>> Overall am still not able to clear visualize on how MTD bindings with > >>>> nvmem cells would look in both partition and un-partition usecases? > >>>> An example DT would be nice here!! > >>> Something along those lines: > >>> > >> This looks good to me. > >>> mtdnode { > >>> nvmem-cells { > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> cell at 0 { > >>> reg = <0x0 0x14>; > >>> }; > >>> }; > >>> > >>> partitions { > >>> compatible = "fixed-partitions"; > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> partition at 0 { > >>> reg = <0x0 0x20000>; > >>> > >>> nvmem-cells { > >>> #address-cells = <1>; > >>> #size-cells = <1>; > >>> > >>> cell at 0 { > >>> reg = <0x0 0x10>; > >>> }; > >>> }; > >>> }; > >>> }; > >>> }; > > >> Just curious...Is there a reason why we can't do it like this?: > >> Is this because of issue of #address-cells and #size-cells Or mtd > >> bindings always prefer subnodes? > >> > >> mtdnode { > >> reg = <0x0123000 0x40000>; > >> #address-cells = <1>; > >> #size-cells = <1>; > >> cell at 0 { > >> compatible = "nvmem-cell"; > >> reg = <0x0 0x14>; > >> }; > >> > >> partitions { > >> compatible = "fixed-partitions"; > >> #address-cells = <1>; > >> #size-cells = <1>; > >> > >> partition at 0 { > >> reg = <0x0 0x20000>; > >> cell at 0 { > >> compatible = "nvmem-cell"; > >> reg = <0x0 0x10>; > >> }; > >> }; > >> }; > >> }; > > It's because partitions were initially directly defined under the mtd > > node, so, if you have an old DT you might have something like: > > > > mtdnode { > > reg = <0x0123000 0x40000>; > > #address-cells = <1>; > > #size-cells = <1>; > > > > partition at 0 { > > reg = <0x0 0x20000>; > > ... > > }; > > ... > > }; > > > > If we use such a DT with this patch applied, the NVMEM framework will > > consider MTD partitions as nvmem cells, which is not what we want. > Yep, I agree. > TBH, I wanted to add compatible string to nvmem-cell at some point in > time and it seems more natural update too. One of the reason we > discussed this in the past was parsers. Looks like mtd can make use of this. > > We should be able to add this as an optional flag in nvmem_config to > enforce this check in case providers wanted to. > > Do you think that would help mtd nvmem case? Yes, it should work if nvmem cells are defined directly under the mtd node (or the partition they belong to). > Also I felt like nvmem-cells subnode seems to be a bit heavy! I still think grouping nvmem cells in a subnode is cleaner (just like we do for partitions), but I won't object if all parties (you, Alban and Rob) agree on this solution.