From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 AA06C340A52; Tue, 23 Jun 2026 08:47:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782204441; cv=none; b=VOlK0j5SDq9JfaxHyXXJF61l+HgSyhTtOOBwsekYM3It/QMaq+NkRKnliVb//Hls5DZ/YHBn91w/RITzw4bJKHSzQsIdwxF8ycTNppqKuvpqjGVp81nlLmmKjw88HyRtikG7USLAQSBN1ewqRXPDTbD4wYPklWQJ5RHlEtZsRwM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782204441; c=relaxed/simple; bh=22XTkqW7CDBu1Unu93XQsfhW/9xKvJM8H0+10waFM08=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=p5K5Uui0mDHh2+lrNcsaf8zCxdKV8Y6I7PqJpYR+ntaNuuMJilj+5tS857kHnVOhRoFXDdt3zmMC1YSIjM1tRVn0VWt3y6uMdg9cst7mU6MEI1KEVqiao5nwe1SgDaFbDLAk79SE6u4JzCX2iAVLv99jkSBerUPoRVxuLCWgh8A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QI+SsjlK; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="QI+SsjlK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 980DD1F000E9; Tue, 23 Jun 2026 08:47:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782204440; bh=x2PkEy5u/GL603lnFnZZuJh+bWGAaKDSaHX9lX4UrfI=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=QI+SsjlKPe4aJthGKAM/stCcBEtoubIOH6yFA9R5C4+UCYVxFviilxQUd4kWlfT1Z T74WwPIUlP4xvFHEpyeGxVWwdi6ttVXmPpqmoUnzb1lxpkpGYgGNSFWiQGq6Izp2+U UwFKWtRxuVqHe6Psz3A3CRvsKjEPmnH+sVLABvwWtrIJjekXGAWjP9rGsj3zZnXq5z 1FaTnVuklEumZbbGSwkXQdsFVqOwv6g040J7mG00POXmjeulffeqE+kJXjqlIucd9L cftdTGOKsfAKPKEanKLoM/k5XrOZSxjG5O/A/Lo6tFrFAj26K+Lz7z32WeO88o4LEW XdsA60OtvyJNg== Date: Tue, 23 Jun 2026 09:47:14 +0100 From: Sudeep Holla To: Pragnesh Papaniya Cc: Cristian Marussi , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Sibi Sankar , MyungJoo Ham , Kyungmin Park , Chanwoo Choi , Dmitry Osipenko , Thierry Reding , Jonathan Hunter , Bjorn Andersson , Konrad Dybcio , Rajendra Nayak , Pankaj Patil , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, arm-scmi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-pm@vger.kernel.org, linux-tegra@vger.kernel.org, Amir Vajid , Ramakrishna Gottimukkula Subject: Re: [PATCH RFC v7 0/9] firmware: arm_scmi: vendors: Qualcomm Generic Vendor Extensions Message-ID: <20260623-busy-beautiful-trout-8cc2ea@sudeepholla> References: <20260610-rfc_v7_scmi_memlat-v7-0-f3f68c608f25@oss.qualcomm.com> <20260616-responsible-junglefowl-of-chaos-7eda7d@sudeepholla> <8725caf9-cebb-49ce-b2c8-4960a6073322@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-pm@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: <8725caf9-cebb-49ce-b2c8-4960a6073322@oss.qualcomm.com> On Fri, Jun 19, 2026 at 06:01:23PM +0530, Pragnesh Papaniya wrote: > > On 16-Jun-26 1:57 PM, Sudeep Holla wrote: > > > Not sure if it was discussed in the previous versions or not, it would be > > good if you can capture why some of bus scaling doesn't work with the existing > > SCMI performance protocol and the monitors don't fit the MPAM mode. > > > > Please capture them in 1/9 as a motivation for this vendor protocol. It will > > then help to understand it better as I am still struggling to. Sorry for that. > > Thanks for the input! > > SCMI perf protocol exports perf domains to kernel where kernel can set > the frequency but here the scaling governor runs on the SCP while kernel > just observes frequency changes made by remote governor. OK if it is sort of read-only w.r.t kernel, why not perf domain notifications work to consume the change done by the SCMI platform. And why do you have set operations in the vendor protocol being proposed then. It all looks like something just cooked up to make things work. I need detailed reasoning as why the existing perf protocol can't work considering all the existing notifications in place. > While MPAM is not enabled/supported on all hardware (Hamoa). Fair enough but I still don't fully understand to rule that out yet. -- Regards, Sudeep