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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id DFCEECD98CE for ; Fri, 12 Jun 2026 13:46:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:Message-ID:Date:References:In-Reply-To:Subject:Cc: To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=4kbuuuOZWUF1RFETFe0hK/FlP92aPI0TPvOQIoPd0E8=; b=Aefs2MmVjFvOgm2rkF4A8Mp9bg blqJYZi+VsTSb+n4ww06oeydvaxiWNCJC0re0Dyoe4soknzLcP7pKhyZ1r6C21pxKZ9aiA8k/aWVF hNrWShfwDyupTkFGApJn1oV+qPqQbqJpYZtPLioq9t1z0ERFVvtXOTlsA0JCscWbM+PT20uXh/IlM BfFYWSsegYqq6nWMnReXBYROXvI5wlV5Cur7cjm88BIFNDWr3qSjhLQt+OqwuHWp0Jwm1oz9X8JaF ZF1qTOkcFWb9XC0ljJZGAu806swsxvfFRcJ5I5pOegNtMatp4axGB6FcDaPycUL7TPSLNA0xFFOFl LX9RpJQQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wY2Cn-0000000B0MF-2iGW; Fri, 12 Jun 2026 13:45:53 +0000 Received: from smtpout-04.galae.net ([185.171.202.116]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wY2Cl-0000000B0LG-01jo for linux-arm-kernel@lists.infradead.org; Fri, 12 Jun 2026 13:45:53 +0000 Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-04.galae.net (Postfix) with ESMTPS id 6BAC8C49F7F; Fri, 12 Jun 2026 13:45:33 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 7DABF60012; Fri, 12 Jun 2026 13:45:30 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id BD0E0106C8B01; Fri, 12 Jun 2026 15:45:27 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1781271929; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=4kbuuuOZWUF1RFETFe0hK/FlP92aPI0TPvOQIoPd0E8=; b=xcIvkfGO6BEMQx4gfN2/H+Sa9bOcBUzyRTA7j5F3DAaNPQ+/ImEN3M+tplPXBhjQkmYBYU hLIjk8oORe2+mOx6efgWHaQ6lxJ3jF5bKQHAtniCl90GqD9YvFmpK1NnOb0UXw9843N2wt 2oU6ZbnPwkj0okTBk4e5tiChliEVEXJ2DENMJoHWvP+VxkbcatMjU/NijU0QZ89uAocdzH nysBLkApkGJ96Uxklp+RLr86FrbouBKVYNPP84+GJ3LqVn4QrK06ZIuMg10grsHaKo837E VC7z2NYTRhnJTWqMa5qJFvB6dLjvMsuYFZYUUrqEebg11KH2B6Q5AycJrqN8xw== From: Gregory CLEMENT To: Arnd Bergmann , Aleksander Jan Bajkowski , arm , soc@kernel.org Cc: Andrew Lunn , Sebastian Hesselbarth , linux-arm-kernel@lists.infradead.org Subject: Re: [GIT PULL] ARM: mvebu: dt64 for v7.2 (#1) In-Reply-To: <8de15abe-8352-41f2-85c6-bdb50eb18e9a@app.fastmail.com> References: <8733z1c8uj.fsf@BLaptop.bootlin.com> <4e690104-b42f-4a2b-ac52-5ebfc82f6853@wp.pl> <956403e3-d47f-498c-9f62-79d39c1cf5db@app.fastmail.com> <8de15abe-8352-41f2-85c6-bdb50eb18e9a@app.fastmail.com> Date: Fri, 12 Jun 2026 15:45:26 +0200 Message-ID: <87o6hfc1op.fsf@BLaptop.bootlin.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Last-TLS-Session-Version: TLSv1.3 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260612_064551_216057_43A2BC5D X-CRM114-Status: GOOD ( 25.97 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hello Arnd, > On Tue, Jun 9, 2026, at 21:29, Arnd Bergmann wrote: >> On Tue, Jun 9, 2026, at 19:35, Aleksander Jan Bajkowski wrote: >>> On 09/06/2026 18:11, Arnd Bergmann wrote: >>>> I'm a bit surprised by this oneline change. Since you successfully tes= ted >>>> this, I assume the change is correct, but I have two questions that >>>> I would like to have an answer for before I pull it. >>> By the way, the upstream safexcel driver works correctly only on=20 >>> coherent >>> platforms. On non-coherent platforms (MediaTek), the SHA-384 and SHA-512 >>> selftests fail. Since the selftests pass on Armada's SoC, I assume I'm= =20 >>> right. >> >> It's not necessarily proof that this is correct, but it is quite likely. >> >> After checking the datasheet some more and finding that this should >> indeed be coherent everywhere, I remembered that even the old >> 32-bit Armada 370 had a coherency manager. At the time, we used a hack >> in arch/arm/mach-mvebu/coherency.c to mark all device nodes as coherent, >> since the original DTB did not contain the correct annotations. >> >> I suspect that the Armada 37xx started out with a copy of the >> old DT files and also never had the annotation, but then never >> had the same hack because arch/arm64 does not have platform >> specific code. > > After investigating a little more, I think the correct fix here > will be to mark all DMA masters in this SoC as dma-coherent. > I thought there was a way to do this for an entire system, > but I could not find that, so this likely has to be done > for each DMA master separately. Thanks for doing this research. I also checked the data in the datasheet before applying the patch, and it appears the platform is coherent. I was surprised that when we initially submitted the support request, Marvel didn't mention this; usually, SoC vendors like to have good performance numbers. However, they also didn't say anything about a coherence issue. The fact that the test succeeded is a good indicator that the SoC is indeed coherent. > > Not sure who still has the hardware and has time to > test this properly. Given that the incorrect DT has > existed for over 10 years now, I assume this is not > urgent and I will skip the pull request for 7.2. I believe I still have a board based on an Armada 3700, and I should be able to find time to do some tests. Gregory > > Arnd --=20 Gr=C3=A9gory CLEMENT, Bootlin Embedded Linux and Kernel engineering https://bootlin.com