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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57ADFC433F5 for ; Thu, 3 Feb 2022 20:11:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353959AbiBCULw (ORCPT ); Thu, 3 Feb 2022 15:11:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53218 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353956AbiBCULv (ORCPT ); Thu, 3 Feb 2022 15:11:51 -0500 Received: from mail-ot1-x32c.google.com (mail-ot1-x32c.google.com [IPv6:2607:f8b0:4864:20::32c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 68F88C061714 for ; Thu, 3 Feb 2022 12:11:51 -0800 (PST) Received: by mail-ot1-x32c.google.com with SMTP id g15-20020a9d6b0f000000b005a062b0dc12so3531691otp.4 for ; Thu, 03 Feb 2022 12:11:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=7el1iFQDw4bHHjq5GbbbknZQamZCeqFF7QzUeFeozJ0=; b=dxb0q5nkfXvISVc9sPcKq2w/gk1eSvVgCJc1YOjrTgiYh8lBGVZ8thOYRegARgW3I6 NO7rhGSMTy+P7UIUJHIHdySpPuj9fMKknuNZUJs40YQU0Kj4m+ktNKmtu5c+DQky6ap+ KkDM/w0J7XaC82zVm7czGssiNXvXrkvUdD4Y1dZaSj9FAl2fJ78A3ds0fPxev+qhoXFI 8CtfiEMlvsnHuEV97IrqL8882YdNb4oDpp1lsNTQLdRUQ6t0xhwfaIR7k1mUJmwY4l8u n7/HD/34mSMweYM6ftG5FzUVzUBk/Hhnc3RvUz7WE74gl6a4+dKmqNZZyxbilnWmO8sM v5Jw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=7el1iFQDw4bHHjq5GbbbknZQamZCeqFF7QzUeFeozJ0=; b=uRaCWv+e3iBRKaeXe5ZnWMH/5h8KRJ80INj5PGojWemD9QuugHWf7gB3NAfjcChtRh L5Q0e2vSA7oDgLaLtiFSIogGjflgcbkKwxm+/pYVnvG4S7NpEPcKTBg620v/88pipoZo bAf8uLwfIS0ZymKmJ/c9OAqobwi10AJqXHlD+fvjP9dQz+Yd07EEdLU3l+ZvjhPHbukd pdnZ5TwLZtN6KhpyKRd7lYt55IU3wkUEVL4yiVp52V28t/Hx+hEQ8Map3ETquRg8Wgel wtIJHZC5+m984znYKg4M1C9llH2o6ySUhTM+rUwqQBOPNKaxVz8Ve5UuslwldOqhzB6I 539Q== X-Gm-Message-State: AOAM530ztad2nRkjRoobf2/KW+gOguRWJIcJtD0YgMLpGnsTguDj7jhb rpNsrUKJ+XJF6uBvzm9mnjqXIQ== X-Google-Smtp-Source: ABdhPJwr83W1t/xwMOlJe8FBsx6hO1Xt7rfdTgFMXYNKaiWJ7C3HscknLVwS6Wset6fIMEmwaHPDGQ== X-Received: by 2002:a9d:68cb:: with SMTP id i11mr19654712oto.256.1643919110741; Thu, 03 Feb 2022 12:11:50 -0800 (PST) Received: from builder.lan ([2600:1700:a0:3dc8:3697:f6ff:fe85:aac9]) by smtp.gmail.com with ESMTPSA id a8sm11458735otj.47.2022.02.03.12.11.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Feb 2022 12:11:50 -0800 (PST) Date: Thu, 3 Feb 2022 14:11:48 -0600 From: Bjorn Andersson To: Rob Herring Cc: Alex Elder , Jakub Kicinski , "Gross, Andy" , David Miller , Matthias Kaehlcke , Evan Green , cpratapa@codeaurora.org, avuyyuru@codeaurora.org, jponduru@codeaurora.org, subashab@codeaurora.org, Alex Elder , linux-arm-msm , netdev , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] arm64: dts: qcom: add IPA qcom,qmp property Message-ID: References: <20220201140723.467431-1-elder@linaro.org> <20220202210638.07b83d41@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Thu 03 Feb 08:44 CST 2022, Rob Herring wrote: > On Thu, Feb 3, 2022 at 5:27 AM Alex Elder wrote: > > > > On 2/2/22 11:06 PM, Jakub Kicinski wrote: > > > On Tue, 1 Feb 2022 08:07:23 -0600 Alex Elder wrote: > > >> At least three platforms require the "qcom,qmp" property to be > > >> specified, so the IPA driver can request register retention across > > >> power collapse. Update DTS files accordingly. > > >> > > >> Signed-off-by: Alex Elder > > >> --- > > >> > > >> Dave, Jakub, please let Bjorn take this through the Qualcomm tree. > > > > > > I don't know much about DT but the patch defining the property is > > > targeting net - will it not cause validation errors? Or Bjorn knows > > > to wait for the fixes to propagate? Or it doesn't matter? :) > > > > It might matter sometimes, but in this case it does not. > > > > If the DT property is present but never referenced by the > > code, it doesn't matter. > > > > The code in this patch looks up the DT property, and its > > behavior is affected by whether the property is there > > or not. If it's not there, it's treated as an error > > that can be safely ignored. > > > > In the case this fix is actually needed, we'll need > > both the code present and DT property defined. If > > the code is there but not the property, it's OK, but > > the bug won't be fixed quite yet. > > If there's only one possible node that qcom,qmp points to, you can > just get the node by its compatible (of_find_compatible_node()). Then > you don't need a DT update to make things work. Of course, this > doesn't work too well if there are 10 possible compatibles without a > common fallback compatible. > In one of the latest platforms there's two QMP instances, so we decided to make the reference explicit to prepare for the introduction of that. So I intend to pick this patch through the qcom tree. And we don't need to synchronize it with the net-changes; the two changes can go independently and only when they are both in place will the change take effect and the issue resolved. Regards, Bjorn