Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751907AbcLEDau (ORCPT ); Sun, 4 Dec 2016 22:30:50 -0500 Received: from conssluserg-01.nifty.com ([210.131.2.80]:45877 "EHLO conssluserg-01.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751328AbcLEDat (ORCPT ); Sun, 4 Dec 2016 22:30:49 -0500 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-01.nifty.com uB53UW0B017365 X-Nifty-SrcIP: [209.85.213.175] MIME-Version: 1.0 In-Reply-To: References: <1480183585-592-1-git-send-email-yamada.masahiro@socionext.com> <1480183585-592-40-git-send-email-yamada.masahiro@socionext.com> <20161201160511.ahlibszokg547wxk@rob-hp-laptop> From: Masahiro Yamada Date: Mon, 5 Dec 2016 12:30:31 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 39/39] mtd: nand: denali_dt: add compatible strings for UniPhier SoC variants To: Dinh Nguyen Cc: Marek Vasut , Rob Herring , "linux-mtd@lists.infradead.org" , "devicetree@vger.kernel.org" , Linux Kernel Mailing List , Boris Brezillon , Brian Norris , Richard Weinberger , David Woodhouse , Cyrille Pitchen , Mark Rutland , Dinh Nguyen , Alan Tull , Chin Liang See , Dinh Nguyen Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3823 Lines: 104 Hi Dinh, 2016-12-04 7:08 GMT+09:00 Dinh Nguyen : > Hi, > > On Fri, Dec 2, 2016 at 8:49 PM, Marek Vasut wrote: >> On 12/03/2016 03:41 AM, Masahiro Yamada wrote: >>> Hi Rob, >> >> Hi! >> >>> 2016-12-03 1:26 GMT+09:00 Rob Herring : >>> >>>>> >>>>> >>>>> (Plan A) >>>>> "denali,socfpga-nand" (for Altera SOCFPGA variant) >>>>> "denali,uniphier-nand-v1" (for old Socionext UniPhier family variant) >>>>> "denali,uniphier-nand-v2" (for new Socionext UniPhier family variant) >>>>> >>>>> (Plan B) >>>>> "altera,denali-nand" (for Altera SOCFPGA variant) >>>>> "socionext,denali-nand-v5a" (for old Socionext UniPhier family variant) >>>>> "socionext,denali-nand-v5b" (for new Socionext UniPhier family variant) >>> >>>> Let the Altera folks worry about their stuff. At least for soft IP in >>>> FPGA, it's a bit of a special case. The old string can remain as bad >>>> as it is. >>> >>> >>> Hmm, I am not sure if this IP would fit in FPGA >>> (to use it along with NIOS-II?) >>> >>> (even if it happened, nothing of this IP would be customizable on users' side. >>> When buying the IP, SoC vendors submit a list of desired features. >>> Denali (now Cadence) generates the RTL according to the configuration sheet. >>> The function is fixed at this point. So, generic compatible would be >>> useless anyway.) >>> >>> >>> If we are talking about SOCFPGA, >>> SOCFPGA is not only FPGA. Rather "SOC" + "FPGA". >>> It consists of two parts: >>> [1] SOC part (Cortex-A9 + various hard-wired peripherals such UART, >>> USB, SD, NAND, ...) >>> [2] FPGA part (User design logic) >>> >>> The Denali NAND controller is included in [1]. >>> So, as far as we talk about the Denali on SOCFPGA, >>> it is as hard-wired as Intel, Socionext's ones. >> >> That's correct, the Denali NAND IP in altera socfpga is a hardware >> block. You can make it available to the fabric too, but by default >> it's used by the ARM part of the chip, so for this discussion, you >> can forget that the FPGA part exists altogether. >> >> I would be in favor of plan B, since it seems to be the more often >> taken approach. A nice example is ci-hdrc: >> >> $ git grep compatible drivers/usb/chipidea/ >> >>>> I simply would do "socionext,uniphier-v5b-nand" (and v5a). >>>> The fact that it is denali is part of the documentation. >>>> >>> >>> Let me think about this. >>> >>> Socionext bought two version of Denali IP, >>> and we are now re-using the newer one (v5b) for several SoCs. >>> Socionext has some more product lines other than Uniphier SoC family, >>> perhaps wider re-use might happen in the future. >>> >>> At first, I included "uniphier" in compatible, but I am still wondering >>> if such a specific string is good or not. >>> >>> Also, comments from Altera engineers are appreciated. > > Sorry, it's taken me a while to add comments. My altera email is very spotty now > that the Intel merge is completed. Please use dinguyen@kernel.org for any future > communications. > > Yes, everything that is said so far for the NAND controller on the > SoCFPGA is correct. I added the binding for the controller a while > back, but unfortunately, we never added the NAND interface to the > devkit, so we did not do much in terms of enabling it. > > I think the only SoCFPGA board I know that has the NAND interface active is > the TRCom board, but I have never seen that board. > > I don't have any strong opinions on this matter, just as long as the > original binding > "denali,denali-nand-dt" is kept, and I think Rob was ok with keeping > that binding. > I am proposing to add "altera,denali-nand" for Altera. For what, do you need the generic compatible? This IP has no default for it to fallback to. -- Best Regards Masahiro Yamada