From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id EA9E82C2372 for ; Mon, 29 Dec 2025 22:12:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767046334; cv=none; b=rXC3MReVRIA+tbpmEHD2oCrUGVYZ3IY5CNNU0LXry3F2JWMU4jKrtZuX9f/2uruazvqI/Qd2uNQsD6RCRCeHMvGKk2kTL37C8XWpHQx5eX0dlsRlwZtg3d3c6bkgXKRQql6PSdwmG+DQTlI7iTPIsdNh95wpIrHSbnALxmgHeT4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767046334; c=relaxed/simple; bh=Q97l49UMcLW/9HbN7nVb7C9OE3vu87fPNbVab3j4xoU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eseeDKXebdPmsqWhcQ6cvquoQHh/vq/QKKov84heOx2+SkjoozzKuv4CQISHHjX2YwvA18loOXCdR5/+ir2OqqSoXQm4U8ObJdA2y66F8JoVaae77DamTXrvk08n33CPbqw6nUMu0o05GdBGI2M1XEox302Zri0tDHs3xBrJ3hk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AFEB4497; Mon, 29 Dec 2025 14:12:02 -0800 (PST) Received: from arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EBCC23F694; Mon, 29 Dec 2025 14:12:04 -0800 (PST) Date: Mon, 29 Dec 2025 23:12:06 +0100 From: Beata Michalska To: "zhenglifeng (A)" Cc: Will Deacon , catalin.marinas@arm.com, rafael@kernel.org, viresh.kumar@linaro.org, sudeep.holla@arm.com, gregkh@linuxfoundation.org, dakr@kernel.org, ionela.voinescu@arm.com, linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org, linuxarm@huawei.com, jonathan.cameron@huawei.com, vincent.guittot@linaro.org, zhanjie9@hisilicon.com, lihuisong@huawei.com, yubowen8@huawei.com, zhangpengjie2@huawei.com, wangzhi12@huawei.com, linhongye@h-partners.com Subject: Re: [PATCH v6 0/3] arm64: topology: Handle AMU FIE setup on CPU hotplug Message-ID: References: <20251119081356.2495290-1-zhenglifeng1@huawei.com> <9b6882dc-a91a-42d6-bf76-347338930d71@huawei.com> <29253319-ced9-4ab6-a58e-28afdf235cde@huawei.com> <62ad0257-aa50-4ab6-bd46-64c3963e4b94@huawei.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: <62ad0257-aa50-4ab6-bd46-64c3963e4b94@huawei.com> On Sat, Dec 20, 2025 at 05:09:52PM +0800, zhenglifeng (A) wrote: > On 2025/12/13 4:08, Will Deacon wrote: > > On Fri, Dec 12, 2025 at 05:27:09PM +0800, zhenglifeng (A) wrote: > >> On 2025/12/2 23:31, Beata Michalska wrote: > >>> On Tue, Dec 02, 2025 at 11:05:25AM +0800, zhenglifeng (A) wrote: > >>>> On 2025/12/1 23:27, Beata Michalska wrote: > >>>>> Hi, > >>>>> > >>>>> Apologies for the delay in reviewing this - currently in progress.... > >>>>> Out of curiosity: what's the cpufreq driver used for testing this series ? > >>>> > >>>> I used cppc_cpufreq for testing this. But with some modifications in > >>>> processor_driver.c, or you'll find that the driver will fail to load with > >>>> maxcpus set. The modification below is only a temporary solution. I'm still > >>>> working on that. > >>>> > >>> Right, so overall the implementation looks good - thanks for that. > >>> There are two issues though with the cppc cpufreq driver. > >>> > >>> One: as you have already noticed - it fails to register when > >>> cpumask_present != cpumask_online. > >>> > >>> Second: it will mix the sources of the freq scale if not all CPUs within the > >>> policy have AMUs enabled/valid. This is due to the fact that at the time of > >>> registering the driver and initializing the FIE support policy->cpus == > >>> policy->related_cpus. Assuming scenario when there are two CPUs within the > >>> policy, one being offline and missing valid AMU counters, > >>> the topology_set_scale_freq_source from cppc cpufreq driver will register > >>> the tick handler for both CPUs, whereas AMU support will (rightly so) register > >>> only for the firs one. When the second CPU comes online, the mismatch will be > >>> detected and the arch callback will get cleared for the first CPU, but the > >>> second one will remain unchanged. > >>> > >>> That said, I do not think any of those issues is a blocker for this series. > >>> But both would need fixing. > >> > >> I believe Beata is OK with this series. So I think we can move ahead with it > >> now. > > > > Please repost at -rc1. It would be nice to have an Ack from Beata... > > Hi Beata, > > It would be nice if you could give this patch an Ack. > > Thanks. > Apologies, 've been away. Acked-by: Beata Michalska --- BR Beata > > > > Will > > >