From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F2216EAE7; Tue, 30 Dec 2025 10:36:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767090962; cv=none; b=SQ3TxfVVOrrrqXGVBZPYGm93sQoIHvTEx4SRWnWVNU/3nEhmRYvLsoK9SEkkP9b9qgbVIYqbqmg3gRZywxjopMq6LRovSsjq0qW9PDaVc7aVtfQkI7FSaCqO+mJQ/Fti05BBUI6mwIGwtQAivc1AR7gqT6GXiXOPIkjm4AyTNSQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767090962; c=relaxed/simple; bh=Gn3RwqUQBzB5nVQ0sZWaLT/mNNpxI1bWWgHK3485eIg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=tlM2a3h0H1OMqLMa83msa7Lfe0o8a1ZHZSusJtELwJ1nADT3cslemCn6OqL2ilylkoNZZL4WzTwfuS1IT9W1HmXarHdeuyurGwM/vWp9t2eaL1rB5g7rctjdXXb4zeey/2DF+4KHfr+/9ZhClqlFPMeNedw9cR6Z0/oM8jDIdos= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=f4w/nnIC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="f4w/nnIC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1EFEBC4CEFB; Tue, 30 Dec 2025 10:35:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767090961; bh=Gn3RwqUQBzB5nVQ0sZWaLT/mNNpxI1bWWgHK3485eIg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=f4w/nnICKw/TEupGp7JyyrW00yk/mYtZVwS9KRygfAJ1Oiy7rFDCN7EJ0XjEXIRSL 5UH2Wl5rBjNFWsjUmNpMJQAJBYt8wbv3Nq7t2B4ZBFZ2oC/dWEaN+cFDVA3rq821ad jGmsQbHGwZ6S9opO+Np2ibHtKyFClDjderhCjNIooai6rujrgVSEzJDrmMT5uLJ2xx majXxT5xODLlhQiCp1OkgErEbThnX5hkGBlqp71pyIwb6dkT4DkKoYxGsmuWJ3Gtyq 69Gb2Gu/7p3ivFXsADz2EvMMJ2nx/2fOm4aPet8yV62o7Y+fqkh+cqO9eiDt0jc8ux OMw4Q6P03xH5g== Date: Tue, 30 Dec 2025 11:35:55 +0100 From: Niklas Cassel To: manivannan.sadhasivam@oss.qualcomm.com Cc: Manivannan Sadhasivam , Lorenzo Pieralisi , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , Rob Herring , Bjorn Helgaas , Bartosz Golaszewski , linux-pci@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Chen-Yu Tsai , Brian Norris , Krishna Chaitanya Chundru , Alex Elder , Bartosz Golaszewski , Chen-Yu Tsai Subject: Re: [PATCH v3 0/7] PCI/pwrctrl: Major rework to integrate pwrctrl devices with controller drivers Message-ID: References: <20251229-pci-pwrctrl-rework-v3-0-c7d5918cd0db@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251229-pci-pwrctrl-rework-v3-0-c7d5918cd0db@oss.qualcomm.com> On Mon, Dec 29, 2025 at 10:56:51PM +0530, Manivannan Sadhasivam via B4 Relay wrote: > Hi, > > This series provides a major rework for the PCI power control (pwrctrl) > framework to enable the pwrctrl devices to be controlled by the PCI controller > drivers. > > Problem Statement > ================= > > Currently, the pwrctrl framework faces two major issues: > > 1. Missing PERST# integration AFAICT, and from reading your reply here: https://lore.kernel.org/linux-pci/ibvk4it7th4bi6djoxshjqjh7zusbulzpndac5jtqkqovvgcei@5sycben7pqkk/ I suppose maybe you plan to enhance pwrctrl so it can assert/deassert individual PERST# in the hierarchy? "No, that plan has been dropped for good. For now, PERST# will be handled entirely by the controller drivers. Sharing the PERST# handling with pwrctrl proved to be a pain and it looks more clean (after the API introduction) to handle PERST# in controller drivers." Thus, it seems that even after this series, pwrctrl will be missing PERST# integration. Perhaps the cover letter could be rephrased to more clearly highlight this. Because it seems a bit weird that the first point of the problem statement (missing PERST# integration) will still be the case after this series. Kind regards, Niklas