From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f171.google.com (mail-pl1-f171.google.com [209.85.214.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 72FE74C63D for ; Tue, 27 Feb 2024 17:08:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709053732; cv=none; b=qQ59s0VNLrWg5iNNh3AtWltbe8+9Al9BOSdKI6ZqbjW7SNlXxLQXG4c0WUb9Y1rbaxscNxlcGi+YPfpS18xlSinyxGX/9+EsCsDb/eO5CwLoK37YW381FAuwFZtY1CUyudxmXIL5ijaiYqdv5RnFMIiGZx7YBokhGeIfQqdDQCM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709053732; c=relaxed/simple; bh=LyIC2a8YCi8H35J3OmUP2FanwA/jMrbgvLb5jpkEIFM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Z48XCZvJpmrBOP8dwajzNQfpMwpIznw/WJ700PZDxxXQq3QGSMJyx7RaCR8EcCPLDF0CJN5XDQly5X9Szo69tyvlDG4WAaj9Z64i/g/ZeRyiN5agcY3BN5kgCJ7FrAN7c7BWvps4XM2MlegiBfZ39eUP4URHg2p0FK5OHIFCxd0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b=OV1FbHlu; arc=none smtp.client-ip=209.85.214.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="OV1FbHlu" Received: by mail-pl1-f171.google.com with SMTP id d9443c01a7336-1dc75972f25so38259855ad.1 for ; Tue, 27 Feb 2024 09:08:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1709053729; x=1709658529; darn=vger.kernel.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=lmc3sjc8em17oChCJSQpaOzbhd1qpZMy7Z0nwlTPyEc=; b=OV1FbHluXUQPzO7NWQ4faDtrR1AkKEeiRAfRi/Yoqt1b9ql8Ne85nQy1UPWVbl91lv AdZpy+i78t4JRIivHJDth32osYdT9Nv+OJ7DCro5zZFlHp0+9cj7raWYuD5wgfgW4w6B 0e5ONboExYxPEjlR//w5nvSveC7Nn1DlZBcu73j35kPznjlDSAu5ezY9HNxOp+P29rNZ Nw4Xm5SJTlxNtawSsP6ZJqqlclKODCgezbhSLwy/CEnSZxJO7H9yTNSFc9MsT9u0aOKB ONoyzPGs8Ab+kTrRnrbwdGLc3kT6/tVW4HnEcnKyN9I6le7xE6uGOAhxTdWi1xdDEChi bSFg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1709053729; x=1709658529; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=lmc3sjc8em17oChCJSQpaOzbhd1qpZMy7Z0nwlTPyEc=; b=r4EC01+i6Ax5Do1PR0dtaTpXLDlzBiuchBSRlRlGTmTKJP50zviDxbOjjy/RLVsmWE 76Ek4vC9ghdvv8H4yPtYV6V1pdyI0FJho6WLrr4M3cvUMfBL0s6w0f0Wcv/IqSA5+VEj vHtlpvQ3Rq3qfPUgNABzIqGA6eweukPwbUm/SIpAnJiGBBbHRwMJpQzfsbxj3nIbzhqw KBBeRvsdHvsSt4fQSg6HYoWO4/LE9n44oiqI7SJPTrTAPZiQpnHg+JRNEUWV0tudUeWd RLd42pkKxl/0JhV4CPvXhi0yJKcqH4N7m6BZrpg1ovfdDAAmflEyh9VaeQ6XXZO87Bwj iqBQ== X-Forwarded-Encrypted: i=1; AJvYcCXlVyGirqUwj1oZ+XZxvX7CH08eFSyCP6pk1pFNlygPZaAN8/5O4+xGmkGiFyZVCdXAO5/ZiNmG8Ig3K3WlX4RZ/tHg1Jr7HanGGreOYg== X-Gm-Message-State: AOJu0Yx4N6hgkt3etY6AoaPVuhVGtAho//HETTDkL+5A1pgVgnbjlaBi dmQd6nVR4KDhe05xx2l3QGRgg2SSluBCZSRIBjyCZZmkaPT3bXgMVXIwes4BGg== X-Google-Smtp-Source: AGHT+IHfCTuVOr5Vdon+2BmyjsKL8DKicx4h9TEm+qIcTGywS1ZZGmFjLcn17HKfB8h/qvkApA/qPA== X-Received: by 2002:a17:902:6b49:b0:1d9:8832:f800 with SMTP id g9-20020a1709026b4900b001d98832f800mr9202931plt.8.1709053729485; Tue, 27 Feb 2024 09:08:49 -0800 (PST) Received: from thinkpad ([117.213.97.177]) by smtp.gmail.com with ESMTPSA id d1-20020a170902c18100b001c407fac227sm1765279pld.41.2024.02.27.09.08.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Feb 2024 09:08:48 -0800 (PST) Date: Tue, 27 Feb 2024 22:38:40 +0530 From: Manivannan Sadhasivam To: Bjorn Helgaas Cc: Bjorn Helgaas , Bjorn Andersson , Konrad Dybcio , Lorenzo Pieralisi , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Rob Herring , Lukas Wunner , Mika Westerberg , quic_krichai@quicinc.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH v3] PCI: Add D3 support for PCI bridges in DT based platforms Message-ID: <20240227170840.GR2587@thinkpad> References: <20240227073057.GF2587@thinkpad> <20240227162535.GA239073@bhelgaas> Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20240227162535.GA239073@bhelgaas> On Tue, Feb 27, 2024 at 10:25:35AM -0600, Bjorn Helgaas wrote: [...] > > Ok, I got the issue. TBH, I added the device tree property based on > > the existing quirks for the ACPI devices. But none of the DT based > > platforms I'm aware of (even the legacy Qcom MSM8996 chipset > > released in early 2016) doesn't have any issue with D3hot. But I'm > > just nervous to assume it is the case for all the DT based platforms > > in the wild. > > > > But to proceed further, what is your preference? Should we ammend > > the DT property to make it explicit that the propery only focuses on > > the D3hot capability of the bridge and it works as per the spec > > (PMCSR) or bite the bullet and enable D3hot for all the non-ACPI > > platforms? > > > > We can add quirks for the bridges later on if we happen to receive > > any bug report. > > I would assume all devices support D3hot via PMCSR per spec. We can > add quirks if we discover something that doesn't. > When you say "all devices", are you referring to bridges in DT platforms or the bridges across all platforms? - Mani > If we add annotations that "this device works correctly", we're > digging a hole for ourselves because it's impossible to remove those > annotations and they complicate all future maintenance. > > Bjorn -- மணிவண்ணன் சதாசிவம்