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=-5.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, 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 591ECC10F13 for ; Thu, 11 Apr 2019 21:52:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1B1BE20850 for ; Thu, 11 Apr 2019 21:52:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b="iOwaAnI7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726773AbfDKVwY (ORCPT ); Thu, 11 Apr 2019 17:52:24 -0400 Received: from esa2.hgst.iphmx.com ([68.232.143.124]:39624 "EHLO esa2.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726629AbfDKVwY (ORCPT ); Thu, 11 Apr 2019 17:52:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1555019589; x=1586555589; h=subject:to:cc:references:from:message-id:date: mime-version:in-reply-to:content-transfer-encoding; bh=ilspfxUHJKcoo3sL9+0K8u6s2ce0sqEfsxwX6p5DqYo=; b=iOwaAnI7jFGx4A7eeqCs/+x4zH2VoRsO7Y2Gwt3lRyikdPyA+8heZCWw kmgS1wQN16DTejAWfdQlgrw99E9xixlI8tFkUbjmfnm06MnDU+fBDnah2 cRlwt+w/2DiHt6F92qRugWaLOadQbERWyZq2FnwG2gTjIRrRKkb1UcCwQ HOX6qp8bmNNXKmK0g2lmmnfq1de88x746g2mZbAyCd2W1GkyPs8QUPXDq V7xawNNjBqR4fOqxY/ooLDFHhzlJWL+sn139596Bz/kJc3Cleo4Nz5dcM 5USueCvbb8ELQQpOcN93QOusSlFN6+o0n0YDUKHDGFDxc/4kxvt2OMN45 Q==; X-IronPort-AV: E=Sophos;i="5.60,338,1549900800"; d="scan'208";a="204596614" Received: from uls-op-cesaip01.wdc.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 12 Apr 2019 05:53:08 +0800 IronPort-SDR: Vf1AI95NOxe8bWCPoJcuL9LLdrl+6bskEiyvU6qixfNosPCw0h4oWFl8NW6eupJ5UGAAhisAYV coOExppayc22ERMryjf34c9Fa33+cQpC/TTEfGld16zj51+JvKh4g0tL2riCieEwYqJU//NWHN VqCOpDgC0INIbw3Dd+aNrKYFDbi6ct+6uf5i46hXR2dAneKBQvPrt/IPxrPAgArmrQ32Ez0Cvw 3yhKdwPxGK6iojatOTCtQeFCPWxtuM273gV29TOQvWwPFhw2lQ7VuJWXfPmjDGQ+Bw8vdCp7U2 /TSGAkT/NnbkwTVzEc23t1UE Received: from uls-op-cesaip01.wdc.com ([10.248.3.36]) by uls-op-cesaep01.wdc.com with ESMTP; 11 Apr 2019 14:29:16 -0700 IronPort-SDR: mlk5eErLAOCUZGN+IRjlNKCz8j2zAdKDBGCygi4RdMre8e99ja9Gd541fsaqmrlOzrkavfte9T s0nTr6Q6z0gVyKEjvJ4OlmJSqrLDYJ2lFzQ3+x2vsvBtLThfBUMWwp0GG8piU01MPhKXD+aidl oilvUtv0O3JSrt8whRKKvDdl9/0FBLsitzxaG46ImNMT/LGkkA/ItAM6hFMGcYven/LrxO5zd5 CBWsFS2JypM6p6e/o2qnKbCtXZxvVBmgEQOHVPXLpZYDAquSd+kxIa+wOqrWvcu08tGdqPmJl/ +zY= Received: from usa001883.ad.shared (HELO [10.86.51.17]) ([10.86.51.17]) by uls-op-cesaip01.wdc.com with ESMTP; 11 Apr 2019 14:52:23 -0700 Subject: Re: [PATCH 1/6] arch: riscv: add support for building DTB files from DT source data To: Paul Walmsley , Christoph Hellwig Cc: "devicetree@vger.kernel.org" , Paul Walmsley , Albert Ou , Palmer Dabbelt , "linux-kernel@vger.kernel.org" , "linux-riscv@lists.infradead.org" References: <20190411084304.5072-2-paul.walmsley@sifive.com> <20190411114616.GA10032@infradead.org> From: Atish Patra Message-ID: <3cf7f2d8-3039-7dd7-e243-77433b1f23a6@wdc.com> Date: Thu, 11 Apr 2019 14:52:22 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/11/19 2:12 PM, Paul Walmsley wrote: > On Thu, 11 Apr 2019, Christoph Hellwig wrote: > >> On Thu, Apr 11, 2019 at 01:42:59AM -0700, Paul Walmsley wrote: >>> Similar to ARM64, add support for building DTB files from DT source >>> data for RISC-V boards. >>> >>> This patch starts with the infrastructure needed for SiFive boards. >>> Boards from other vendors would add support here in a similar form. >> >> What do we build it for? We'd really need something like this: >> >> http://git.infradead.org/users/hch/misc.git/commitdiff/d6242aa147baf57e05e2932199c74d8d24b9926e >> http://git.infradead.org/users/hch/misc.git/commitdiff/0cd5413c8094ab57b68e0629dacfed695f4c1ef1 >> >> To actually use the DT files. > > Those patches might be useful - I have not reviewed them closely - but > they are not necessary. > > The FSBL already supplies a DTB to Linux. I assume the U-boot port works > the same way. > I am bit confused here. I thought the idea behind putting the the DTS in kernel so that Kernel don't need to depend on DT passed from boot loaders. Currently, DTB passed from FSBL is modified by OpenSBI/BBL before passing to U-Boot or Linux. If Linux kernel can boot from the DTS contained within its source code as is, that would be much more helpful. > I haven't switched to U-boot yet for these driver tests, so I personally > have been using the open-source FSBL (freedom-u540-c000-bootloader) with > the following trivial patches applied: > > https://github.com/sifive/freedom-u540-c000-bootloader/tree/dev/paulw/supply-fsbl-dtb-v5.1-rc4 > > The fsbl/ux00_fsbl.dtb file can be symlinked to the kernel DTB output, > e.g., ~/linux/arch/riscv/boot/dts/sifive/hifive-unleashed-a00-fu540.dtb. > > This assumes that FSBL has to be rebuilt every time I want to change the DT. I was hoping to avoid that. Regards, Atish > - Paul > > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv >