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 314133B47F9; Fri, 31 Jul 2026 08:26:28 +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=1785486390; cv=none; b=gZhrj/Y1YKrdP1cJsRtgIl6npEQ67Wv1L+UFddz4lTlP5PbeyU+QJtcUNNwPPbZ7VQHgnYwqDlrBRYQY/XUOthOxnpdnQDbJ+FD6Rqv6HOID0fR8f70N06mT44y8s6Zj33yzXvn1jL1BaJfr0RM533SEkBucw2lO1PIZFgYyA+8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785486390; c=relaxed/simple; bh=lgxIT/Jas/nejvD/2M4MCC2l9S9VYqSU034/2FQsDGQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=T2X5MTU6CiYrGyNLNofbiIkZAp6mbDeyC8pkEhnwPUjAF5ytBFS6NlkRKd7g5NWUrkeuUsT/K93Rzdg394xiakec0hqmU7/HRJOpZ3mjbxNePfEhQVbozz23v0WbgNwBKen5nRYQVQGnLmm9U1OTjb5C9++nhzNZ3ojI+WeiRQE= 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; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=ZGYsZUTJ; 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 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="ZGYsZUTJ" 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 528C5204C; Fri, 31 Jul 2026 01:26:24 -0700 (PDT) Received: from [192.168.178.24] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 095FD3F86F; Fri, 31 Jul 2026 01:26:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1785486388; bh=lgxIT/Jas/nejvD/2M4MCC2l9S9VYqSU034/2FQsDGQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=ZGYsZUTJppQSYW8a0oBCzKKt3gI6KiC5UOV3Dvzy40qxergb0EFEaiECLh2Lslrkq zqhnP6jtOX3LZD5KmwAQ8QgsJiDtUwTNxt5wvfkimkCwCqwFk3yKbHv2LKnk6W8UK9 zUE5W4NW+UcrAyj2kT2NU9uQ3UM73BS/lryf3deU= Message-ID: Date: Fri, 31 Jul 2026 10:26:23 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 10/10] arm_mpam: detect and enable MPAM-Fb PCC support To: Ben Horgan , Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Catalin Marinas , Will Deacon , "Rafael J . Wysocki" , Len Brown , James Morse , Reinette Chatre , Fenghua Yu Cc: Jonathan Cameron , Srivathsa L Rao , Ganapatrao Kulkarni , Trilok Soni , Srinivas Ramana , Niyas Sait , Lee Trager , Ritwick Sharma , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20260730152539.2712312-1-andre.przywara@arm.com> <20260730152539.2712312-11-andre.przywara@arm.com> <0511693b-5855-4419-8e1a-8444cfdd4253@arm.com> Content-Language: en-GB From: Andre Przywara In-Reply-To: <0511693b-5855-4419-8e1a-8444cfdd4253@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Ben, On 7/31/26 10:22, Ben Horgan wrote: > Hi Andre, > > On 7/31/26 09:16, Andre Przywara wrote: >> Hi Ben, >> >> On 7/30/26 18:13, Ben Horgan wrote: >>> Hi Andre, >>> >>> On 7/30/26 16:25, Andre Przywara wrote: >>>> The Arm MPAM-Fb specification [1] describes a protocol to access MSC >>>> registers through a firmware interface. This requires a shared memory >>>> region to hold the message, and a mailbox to trigger the access. >>>> For ACPI this is wrapped as a PCC channel, described using existing >>>> ACPI abstractions. >>>> >>>> Add code to parse those PCC table descriptions associated with an MSC, >>>> and store the parsed information in the MSC struct. >>>> There can be multiple PCC channels, and each channel can serve multiple >>>> MSCs, so we need to keep track of the channel usage, using a list and >>>> a refcount. >>>> >>>> This will be used by the MPAM-Fb access wrapper code. >>>> >>>> [1] https://developer.arm.com/documentation/den0144/latest >>>> >>>> Signed-off-by: Andre Przywara >>>> Tested-by: Ritwick Sharma >>> Ritwick gave his Tested-by for the series on v5. Any reason to just add the tag on this patch? >> >> submitting-patches.rst says: >> "Both Tested-by and Reviewed-by tags, once received on mailing list from tester or reviewer, should >> be added by author to the *applicable* patches when sending next versions." >> >> I think this system relies on MPAM-Fb, so he couldn't test each patch in isolation, but "just" that >> MPAM-Fb works, which is what only patch 10/10 enables. >> >> So I find tags given for the whole series always tricky to handle, but in this case I figured patch >> 10/10 would be the right target. > > Ok, yes. I agree with that principle - I'm still learning how these things are done. Perhaps patch 8 > would have been relevant too. That's actually a good point, will do this. Thanks, Andre >>> I guess patch 9 has significant enough changes to drop tags but I don't see it for the others. >> >> Well, even smaller changes could ruin a whole thing, but IIUC in this case Ritwick's setup doesn't >> even enable error IRQs, so this part wasn't tested anyway. > > >> >> Cheers, >> Andre. >> >