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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 7DF18C10F0E for ; Wed, 10 Apr 2019 02:41:34 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4BB5D206B7 for ; Wed, 10 Apr 2019 02:41:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="PBQuScQU"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="MpD60NwV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4BB5D206B7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nvidia.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=MvTi6xWbiijZl/Y6FlG0jkrFxhaJrTRNtMvrB4i3+EM=; b=PBQuScQUq/APplvGmkH30rTjx iPtCo66poaJO7sxxgX93i8h+mT7/FVDdjy0HZCKFaxDxUOvchErsJwV2tZF1YyE0ZeH4xJ5CmlbNP OKD5DbXGhqtd71xvBVct4iRTsYpKW5wLo7JHqHAJYyaGAh5NZCJujsveaiSHOccGjwf/uJdE1S7Pz flpflGlkMbfUa+Wwa06H4tDXgJk2eXG99QuRAk8a7Y882JiqTqfwSHdl02JOWkc5IbybJDCCLDeF0 GT5W5mAVtNH9ujFHPsSSpFK8vo0iSqNm18u01+FkM0oxiHpW3Xy7GwI8Z0Pi8HrMCcLbRn6AAZ3Lx niXN90hlQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hE3B7-00017r-GO; Wed, 10 Apr 2019 02:41:33 +0000 Received: from hqemgate14.nvidia.com ([216.228.121.143]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hE3B4-00017T-Ab for linux-arm-kernel@lists.infradead.org; Wed, 10 Apr 2019 02:41:31 +0000 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate14.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Tue, 09 Apr 2019 19:41:33 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Tue, 09 Apr 2019 19:41:29 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Tue, 09 Apr 2019 19:41:29 -0700 Received: from [10.19.108.132] (172.20.13.39) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Wed, 10 Apr 2019 02:41:26 +0000 Subject: Re: [PATCH 1/8] dt-bindings: memory: tegra: Add Tegra210 EMC bindings To: Rob Herring References: <20190325074523.26456-1-josephl@nvidia.com> <20190325074523.26456-2-josephl@nvidia.com> <5ca06133.1c69fb81.11ebf.91ce@mx.google.com> <7d680700-d2f2-7b6c-a8bf-dca6d54dbf2c@nvidia.com> From: Joseph Lo Message-ID: Date: Wed, 10 Apr 2019 10:41:16 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: X-Originating-IP: [172.20.13.39] X-ClientProxiedBy: HQMAIL106.nvidia.com (172.18.146.12) To HQMAIL101.nvidia.com (172.20.187.10) Content-Language: en-US DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1554864094; bh=k88UGopJw4/bZvRV7iGLn3ImQi0U9f4cG5kiDw7b2MA=; h=X-PGP-Universal:Subject:To:CC:References:From:Message-ID:Date: User-Agent:MIME-Version:In-Reply-To:X-Originating-IP: X-ClientProxiedBy:Content-Type:Content-Language: Content-Transfer-Encoding; b=MpD60NwVgWVGtUhwDKKrScOpoT6Qs6tQ/IFlYf4HZMzLSiLD0HtBd8aEmbokuB5lo La3RxCpd7uLrpCiCt/6KkHwHyyLEi0My6ERhCLh74m7wco9SZ+ycnhr5WVFRMnyQBc ofTtfzLauXM0/s+uKEbJeUXrJy4dw1gialnpQ8yfjgc+NZSqwPESyYanlu2IafGDxW LwYnUYEaLc/kgygHyG61rlKAEWpF7nJJdMiIpkVAm2+nZt3J0xKPCWjb3Sq3aI7UEb rQzJ7a6nPrjuQrGbHZncJuTJzOLLcq01xVaZKKX6qIqnpmey1ZhEJD5SRMNpav2NuO hmlAOUJGgNxfg== X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190409_194130_382549_6A9ADE5D X-CRM114-Status: GOOD ( 18.28 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, Stephen Boyd , Peter De Schrijver , Jonathan Hunter , Thierry Reding , linux-tegra@vger.kernel.org, linux-clk , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 4/3/19 12:26 PM, Rob Herring wrote: > On Mon, Apr 1, 2019 at 2:58 AM Joseph Lo wrote: >> >> On 3/31/19 2:41 PM, Rob Herring wrote: >>> On Mon, Mar 25, 2019 at 03:45:16PM +0800, Joseph Lo wrote: >>>> Add the binding document for the external memory controller (EMC) which >>>> communicates with external LPDDR4 devices. It includes the bindings of >>>> the EMC node and the EMC table of different rates. >>>> >>>> To support high rates for LPDDR4, the EMC table must be trained before >>>> it can be used for runtime clock switching. It has been done by firmware >>>> and merged to the table that Linux kernel uses. For backward >>>> compatibility with the devices that had been launched on the market, like >>>> Shield and Jetson platforms, the bindings in the EMC table should remain >>>> the same. So the firmware can recognize them and merge the trained EMC >>>> table for the kernel. >> >> Hi Rob, >> >> Thanks for reviewing. >> >>> >>> Overall seems pretty bloated. How much of this really varies by board >>> vs. just being a dump of all the register values to stuff? >> >> Most of them are register values. And by different SDRAM devices that >> could be used on the same platform (use ram code to identify them), the >> value could be different. >> >>> >>> Primarily, I'm leary of getting a similar binding for every vendor's DDR >>> setup. >>> >>> Some mostly trivial comments follow. >> >> Really sorry about that. I understand these basic rules for DT bindings, >> but the case here is that these un-reviewed bindings have been used in >> the firmware on the shipped products. To support the same with the >> upstream kernel and consider the firmware blob may not be updated, we >> have no choice to just use the same bindings in the upstream kernel. >> >> How can we deal with this case? > > Simply, we do not accept bindings as-is. If we did, then there would > be no point in documenting and reviewing bindings. NVidia chose this > path and now gets to live with it. Hi Rob, Thanks for letting us know the criterion. We will follow up and continue the reviewing process of the binding. Please help us to review. And we will fix the driver and firmware to use the reviewed bindings later. Need to settle the binding first. Thanks, Joseph _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel